Journal of Threatened Taxa | www.threatenedtaxa.org | 26 February 2021 | 13(2): 17693–17711

 

ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print) 

https://doi.org/10.11609/jott.6535.13.2.17693-17711

#6535 | Received 07 August 2020 | Finally accepted 18 February 2021

 

 

A checklist of earthworms (Annelida: Oligochaeta) in southeastern Vietnam

 

Dang Hai Lam 1, Nam Quoc Nguyen 2, Anh Duc Nguyen 3  & Tung Thanh Nguyen 4

 

1,4 Department of Biology, School of Education, Can Tho University, Post box: 900000, Can Tho, Vietnam.

2 Biotechnology Research and Development Institute, Can Tho University, Post box: 900000, Can Tho, Vietnam.

3 Department of Soil Ecology, Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology,

Post box: 100000, Hanoi, Vietnam.

1 lamhaidangct@gmail.com, 2 namp0916008@gstudent.ctu.edu.vn, 3 ducanh410@yahoo.com,

4 thanhtung@ctu.edu.vn (corresponding author)

 

 

Editor: B.A. Daniel, Zoo Outreach Organisation, Coimbatore, India.         Date of publication: 26 February 2021 (online & print)

 

Citation: Lam, D.H., N.Q. Nguyen, A.D. Nguyen & T.T. Nguyen (2021). A checklist of earthworms (Annelida: Oligochaeta) in southeastern Vietnam. Journal of Threatened Taxa 13(2): 17693–17711. https://doi.org/10.11609/jott.6535.13.2.17693-17711

 

Copyright: © Lam et al. 2021. Creative Commons Attribution 4.0 International License.  JoTT allows unrestricted use, reproduction, and distribution of this article in any medium by providing adequate credit to the author(s) and the source of publication.

 

Funding: Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 106.05-2018.04; Can Tho University Improvement Project VN14-P6, supported by a Japanese ODA loan.

 

Competing interests: The authors declare no competing interests.

 

Author details: Dang Hai LAM and Tung Thanh NGUYEN are currently working for Department of Biology, School of Education, Can Tho University (Can Tho, Vietnam). They are focusing on taxonomy, systematics and ecology of earthworms in Vietnam and surrounding region.  Nam Quoc NGUYEN is currently a PhD student at the Biotechnology Research and Development Institute, Can Tho University (Can Tho, Vietnam). His study objectives are biodiversity and phylogenetic relationship of earthworms in southeastern Vietnam.  Anh Duc NGUYEN is currently working for Department of Soil Ecology, Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology, Hanoi, Vietnam.

 

Author contribution: All authors equally contribute to the current paper, including sample collecting, analyzing, photographing and manuscript writing.

 

Acknowledgements: This research is funded by the Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 106.05-2018.04.  This study is funded in part by the Can Tho University Improvement Project VN14-P6, supported by a Japanese ODA loan.

 

 

 

Abstract: The earthworms of southeastern Vietnam are reported based on literature and samples collected during the period of 2012–2019.  A total of 41 earthworm species of 12 genera in six families are recorded in the southeastern part of Vietnam.  Of these, Polypheretima elongata and Dichogaster affinis are recorded for the first time in the region.  The dominant family is Megascolecidae with 35 species of seven genera while each of the other families is represented by only one species, except for Octochaetidae which has one genus and two species.  The comprehensive checklist also provides data of each species including examined specimens, distributions and remarks.  An identification key to species is compiled for southeastern Vietnam.

 

Keywords: Identification key, survey, Ho Chi Minh, humid, subtropical, data

 

Abbreviation: A—Aclitellate specimens | C—Clitellate specimens | CTU—Can Tho Univesity | IEBR—Institute of Ecology and Biological Resources-Vietnam Academy of Science and Technology | SORC—Soil Organism Research Center – Hanoi National University of Education | NP—National Park | NR—Natural Reserve | Mts—Mountain | ag—accessory gland | amp—ampula | atr—atrium | cl—clitellum | dv—diverticulum | fp—female pore | gm—genital markings | mp—male pore | np—nephridial pore | sg—seminal groove | os—penial seta | sp—spermathecal pore | st—seta.

 

 

Khu hệ giun đất vùng Đông Nam Bộ Việt Nam được tổng kết dựa trên các tài liệu nghiên cứu trước đây và các mẫu vật thu thập trong giai đoạn 2012-2019. Tổng số có 41 loài đất thuộc 12 giống, 6 họ được ghi nhận cho khu vực này. Trong đó, hai loài Polypheretima elongata và Dichogaster affinis được ghi nhận lần đầu tiên ở khu vực Đông Nam Bộ. Họ Megascolecidae là họ chiếm ưu thế với 35 loài, 7 giống, trong khi các họ giun đất khác chỉ gặp 1 loài, 1 giống, và họ Octochaetidae gặp 2 loài, 1 giống. Các thông tin về số lượng cá thể phân tích, phân bố và nhận xét cho từng loài cũng được trình bày chi tiết. Khoá phân loại các loài giun đất cho khu vực cũng được xây dựng.

 

 

 

INTRODUCTION

 

Southeastern Vietnam has an area of 23,607.8km2, located between 10.316–12.2830N & 105.800–107.5830E.  This region is the territory of six provinces and city: Ho Chi Minh, Ba Ria – Vung Tau, Dong Nai, Binh Duong, Binh Phuoc, and Tay Ninh.  The terrain changes from mountainous areas and midlands to coastal deltas.  The region is located in a humid subtropical climate zone featured by the rainy season, which starts in May and lasts till October (average rainfall counted for 90% of the whole year), and the dry season from November to April.  The region has different soil types, but mainly dominated by ferralsols and acrisols (Sterling et al. 2008).

The earthworms of Vietnam in general and of the southeastern part in particular was first reported by Perrier (1872, 1875) with descriptions of four new species.  There were no reports for the southeastern part of Vietnam until 1956 when Omodeo (1956) described six new species.  After that, there were no reports on earthworms in the region for approximate 60 years.  Recently, Nguyen (2014) and Nguyen et al. (2015) reported list of earthworms recorded in small parts of Binh Duong Province.  Nguyen et al. (2015a,b) also described four new species from Dong Nai Province.  All data were synthesized into a comprehensive checklist of earthworms in Vietnam by Nguyen et al. (2016).  After 2016, the earthworms of southeastern Vietnam have been intensively studied, and 14 new species were described from this region (Nguyen & Lam 2017; Nguyen et al. 2018, 2019, 2020a,b).  Together with discoveries of new species, taxonomic acts have also been undertaken.  Nguyen et al. (2017) and Nguyen (2020) corrected Metaphire magophila (Nguyen, 2011) as a senior synonym of M. easupana (Thai & Huynh, 1993).  Samples of M. neoexilis (Thai & Samphon, 1988) found in Binh Duong province were misidentified as Amynthas modigliani (Rosa, 1896).

This work aims to provide comprehensive information on the earthworms of southeastern Vietnam.  An identification key is also provided to facilitate further studies on earthworms in this region.

 

 

MATERIAL AND METHODS

 

The species list was created based on literature, e.g., Perrier (1872, 1875), Omodeo (1956), Nguyen (2014), Nguyen et al. (2015), Nguyen et al. (2015a,b, 2016, 2017, 2018, 2020a,b), Nguyen & Lam (2017), and Nguyen et al. (2019, 2020).  The species was also confirmed by identifying samples collected from 263 sites (Figure 1) during the rainy season (early September to late October) in 2012–2019.

Earthworms were collected by digging and hand-sorting method following Górny & Grum (1993).  After collecting, specimens were cleaned by tap water, killed in 2% formalin, temporally fixed in formalin 4% for 12 hours, then transferred to new formalin 4% for long-term preservation.  All specimens were deposited in the Laboratory of Zoology, Department of Biology, Can Tho University.

The specimens were examined under a motic digital microscope (Model: DM143-FBGG-C) and dissected from the dorsal side for internal observation.  Colour images were taken using a camera attached directly to the microscope, then improved and grouped into plates using Photoshop CS6.

 

 

RESULTS

 

Until date, a total of 41 earthworm species of 12 genera in six families (Almidae, Megascolecidae, Moniligastridae, Octochaetidae, Ocnerodrilidae, and Rhinodrilidae) have been recorded in southeastern Vietnam.  All information of each species is presented in the checklist.  Polypheretima elongata and Dichogaster affinis are reported for the first time in the region.  Megascolecidae was the dominant family in terms of the number of species and genera (35 species of seven genera).  It also corresponded to the earthworm distribution in the Oriental region (Hendrix & Bohlen 2002).  Other families had only one species each except Octochaetidae which had two species in one genus.  Particularly, the genus Metaphire had 20 species while Amynthas was poorly known with only seven species.  Thai (2000) also indicated that Metaphire was the most diverse genus in the south of Vietnam.

In addition, 16 species were described from the southeastern part of Vietnam since 2016.  Therefore, the total earthworm species of Vietnam has increased to 240 in 25 genera and eight families.

 

Family ALMIDAE Duboscq, 1902

Genus Glyphidrilus Horst, 1889

Glyphidrilus papillatus (Rosa, 1890)

(Image 1 a1, Table 1)

Examined material: 2C (CTU-EW.030.02) and 3C (CTU-EW.030.04); data for samples shown in Table 1.

Distribution: Ba Ria-Vung Tau (Dat Do); Binh Duong (Tan Uyen, Dau Tieng, Phu Giao); Ho Chi Minh City (Nha Be); Tay Ninh (Trang Bang).

Remarks: It was found in edges of water ponds or paddy fields.

 

Family MEGASCOLECIDAE Rosa, 1891

Genus Lampito Kinberg, 1867

Lampito mauritii Kinberg, 1867

(Image 2 a1–a2, Table 1)

Examined material: 27C (CTU-EW.002.01), 13C (CTU–EW.002.07), 6C (CTU–EW.002.11), 9C (CTU-EW.002.13), 18C (CTU-EW.002.22), 46C (CTU-EW.002.27), and 21C (CTU-EW.002.32); data for samples were shown in Table 1.

Distribution: Dong Nai (Xuan Loc; Nhon Trach; Long Thanh); Ba Ria-Vung Tau (Vung Tau, Ba Ria, Xuyen Moc, Tan Thanh, Dat Do, Long Dien); Binh Duong (Di An, Dau Tieng, Bau Bang, Thu Dau Mot); Binh Phuoc (Chon Thanh); Ho Chi Minh City (Nha Be, Binh Chanh, Hoc Mon, Cu Chi); Tay Ninh (Trang Bang, Go Dau, Duong Minh Chau, Tan Chau, Tay Ninh).

Remarks: The species was found aggregated in high density in sandy soil and decomposed cow dung.

 

Genus Perionyx Perrier, 1872

Perionyx excavatus Perrier, 1872

(Image 2 b1–b2, Table 1)

Examined material: 1C (CTU-EW.003.02) and 1C (CTU-EW.003.03); data for samples in Table 1.

Distribution: Dong Nai (Nhon Trach); Binh Duong (Di An, Dau Tieng, Bau Bang, Thu Dau Mot, Phu Giao); Ho Chi Minh City (Binh Chanh); Ba Ria-Vung Tau.

Remarks: The species has been bred commonly in local earthworm farms, but rarely found in the wild.

 

Genus Pontodrilus Perrier, 1874

Pontodrilus litoralis (Grube, 1855)

Examined material: No specimen available

Distribution: Ba Ria-Vung Tau (Omodeo 1956)

Remarks: Omodeo (1956) collected samples of the species from mangrove soils (Ba Ria-Vung Tau Province), but there were no other further records in the study area recently.

 

Genus Amynthas Kinberg, 1867

Amynthas dorsomorrioides Nguyen & Nguyen, 2020

(Image 2 f1–f2, Table 1)

Examined material: 1C (CTU-EW.174.h01), 2C (CTU-EW.174.p02), and 2C (IEBR-EW.174.p02); data in Table 1.

Distribution: Ba Ria–Vung Tau (Ba Ria City, Minh Dam Mts).

Remarks: The species is closely similar to A. dorsomorrisi (Do & Tran, 1995), however, distinguished by having spermathecal pores laterally, a pair of genital markings in xvii, first dorsal pore in 12/13, 6–7 setae between two male porophores, intestine swelling at xv, and lobuled typhlosole (Nguyen et al. 2020a).

 

Amynthas exiguus austrinus (Gates, 1932)

(Image 2 d1–d2, Table 1)

Examined material: 4C (CTU-EW.057.01), 5C (CTU-EW.057.02), 14C (CTU-EW.057.03), 8C (CTU-EW.057.04), 8C (CTU-EW.057.05), and 11C (CTU-EW.057.11); data in Table 1.

Distribution: Dong Nai (Vinh Cuu, Thong Nhat, Long Khanh); Binh Phuoc (Bu Dang, Bu Gia Map, Dong Phu, Phuc Long); Ba Ria-Vung Tau (Dat Do); Tay Ninh (Tay Ninh City).

 

Amynthas juliani (Perrier, 1875)

Examined material: No specimen available.

Distribution: Ho Chi Minh City  (Perrier 1875).

Remarks: There were no further reports in the study area since Perrier (1875).

 

Amynthas longiprostaticus Nguyen & Lam, 2020

(Image 2 g1–g2, Table 1)

Examined material: 1C (CTU-EW.088.h01), 5C (CTU-EW.088.p02), 4C (IEBR-EW.088.p02), 30C (CTU-EW.088.03), and 17C (IEBR-EW.088.03); data in Table 1.

Distribution: Dong Nai (Cam My, Cat Tien NP).

Remarks: The species is somewhat similar to A. papilio (Gates, 1930) and A. khaohayod Bantaowong & Panha, 2015.  It is, however, characterized by having the distance between male pores wider, presence of genital markings in the spermathecal region, first dorsal pore in 11/12, and smaller size (Nguyen et al. 2020a).

 

Amynthas minhdam Nguyen & Tran, 2020

(Image 2 h1–h2, Table 1)

Examined material: 1C (CTU-EW.168.h01), 1C (CTU-EW.168.p02), 3C (CTU-EW.168.p03), and 2C (IEBR-EW.168.p03); data Table 1.

Distribution: Ba Ria-Vung Tau (Minh Dam Mts).

Remarks: The species is fairly similar to A. sapinianus (Chen, 1946) and A. morrisi (Beddard, 1892).  It is, however, distinguished by having a pair of genital markings in the male region, chain-shaped seminal chamber, and first dorsal pore in 12/13 (Nguyen et al. 2020a).

 

Amynthas ocularius Nguyen & Lam, 2020

(Image 2 i1–i2, Table 1)

Examined material: 1C (CTU-EW.167.h01), 2C (CTU-EW.167.p02), 3C (CTU-EW.167.p03), and 2C (IEBR-EW.167.p03); data in Table 1.

Distribution: Ba Ria-Vung Tau (Binh Chau-Phuoc Buu NR).

Remarks: The species is somewhat similar to A. compositus (Gates, 1932) and A. papulosus (Rosa, 1896).  It is, however, distinctly different from those congener in having numerous genital markings being arranged in transverse lines in both of the spermathecal and male regions, and being agglomerated into two groups in 19/20, and first dorsal pore in 13/14 (Nguyen et al. 2020a).

 

Amynthas polychaetiferus (Thai, 1984)

(Image 2 e1–e2, Table 1)

Examined material: 29C (CTU-EW.008.01), 10C (CTU-EW.008.04), 11C (CTU-EW.008.07), 20C (CTU-EW.008.10), 10C (CTU-EW.008.18), 6C (CTU-EW.008.21), and 2C (CTU-EW.008.24); data in Table 1.

Distribution: Widely distributed in the study area, but more gathered in Dong Nai and Ba Ria-Vung Tau, little known in Binh Duong and Binh Phuoc, and rarely found in Ho Chi Minh City and Tay Ninh.

Remarks: The species have setae crowded ventrally in xix, varied in numbers or sometimes in usual position.  The species was reported from the study area with the highest frequency and species abundance compared to other places.

 

Genus Metaphire Sims & Easton, 1972

Metaphire anomala (Michaelsen, 1907)

(Image 3 k1–k2, Table 1)

Examined material: 11C (CTU-EW.020.06), 7C (CTU-EW.020.07),  10C (CTU-EW.020.13), 8C (CTU-EW.020.14), and 20C (CTU-EW.020.21); data in Table 1.

Distribution: Dong Nai (Vinh Cuu, Xuan Loc, Dinh Quan, Trang Bom, Cam My, Long Thanh); Ba Ria-Vung Tau (Chau Duc, Xuyen Moc, Tan Thanh, Ba Ria City); Binh Duong (Tan Uyen; Binh Phuoc: Phu Rieng); Tay Ninh (Duong Minh Chau, Tay Ninh City).

Remarks: The species is morphologically different from the original description of Michaelsen (1907) by having male pore in xix, four pairs of spermathecal pore in 5/6/7/8/9, no genital markings, and bigger size.

 

Metaphire bahli (Gates, 1945)

(Image 2 j1–j2, Table 1)

Examined material: 30C (CTU-EW.004.01), 30 (CTU-EW.004.02), 22 (CTU-EW.004.03),16 (CTU-EW.004.04), 28C (CTU-EW.004.19), 19C (CTU-EW.004.24), 20C (CTU-EW.004.25), 39C (CTU-EW.004.54), and 30C (CTU-EW.004.62); data in Table 1.

Distribution: Widely distributed in southern Vietnam.

 

Metaphire bariaensis Nguyen, Nguyen, Lam & Nguyen, 2020

(Image 3 l1–l2, Table 1)

Examined material: 1C (CTU-EW.169.h01), 2C (CTU-EW.169.p02), 3C (CTU-EW.169.p03), and 15C (CTU-EW.169.04); data in Table 1.

Distribution: Ba Ria-Vung Tau (Ba Ria, Bao Quang Mts).

Remarks: The species is somewhat similar to M. truongsonensis (Thai, 1984); however, it is characterized by having spermathecal pores located laterally and separated intestinal caeca (Nguyen et al. 2020b).

 

Metaphire cf. campanulata (Rosa, 1890)

(Image 2 k1–k2, Table 1)

Examined material: 17C (CTU-EW.018.01), 14C (CTU-EW.018.09), 14C (CTU-EW.018.11), 25C (CTU-EW.018.20), 4C (CTU-EW.018.34), and 8C (CTU-EW.018.36); data in Table 1.

Distribution: Commonly found in the study area.

Remarks: The species is closely similar to M. houlleti (Perrier, 1872) but it is characterized by mushroom-shaped spermathecae, first dorsal pore in 11/12, and bigger size.

 

Metaphire easupana (Thai & Huynh, 1993)

(Image 2 l1–l2, Table 1)

Examined material: 5C (CTU-EW.012.04), 35C (CTU-EW.012.05), 10C (CTU-EW.012.10), 25C (CTU-EW.012.17), and 23C (CTU-EW.012.26); data in Table 1.

Distribution: Dong Nai (Vinh Cuu, Xuan Loc, Dinh Quan); Ba Ria-Vung Tau (Tan Thanh, Ba Ria City, Long Dien: Minh Dam Mts); Tay Ninh (Ba Den Mts).

Remarks: The species was known as M. magophila (Nguyen, 2011), but it was synonymized by Nguyen et al. (2017).

 

Metaphire grandiverticulata Nguyen & Lam, 2017

(Image 3 a1–a2, Table 1)

Examined material: 1C (CTU-EW.089.h01), 9C (CTU-EW.089.p02), 13C (CTU-EW.089.03), and 24C (CTU-EW.089.04); data in Table 1.

Distribution: Dong Nai (Long Khanh); Ho Chi Minh City (Hoc Mon).

Remarks: The species is similar to M. neoexilis (Thai & Samphon, 1988), but it is characterized by having large and stout spermathecal diverticula and ventrally connected testes sacs (Nguyen & Lam 2017).

 

Metaphire haui Nguyen, Nguyen, Lam & Nguyen, 2020

(Image 4 a1–a2, Table 1)

Examined material: 1C (CTU-EW.172.h01), 4C (CTU-EW.172.p02), 2C (CTU-EW.172.p03), and 4A (CTU-EW.172.p04); data in Table 1.

Distribution: Ba Ria-Vung Tau (Dinh Mts, Tan Thanh).

Remarks: The species is fairly similar to M. peguana (Rosa, 1890), but it is distinguished by having spermathecal pores located laterally, first dorsal pore in 7/8, and genital markings in xvii and xix (Nguyen et al. 2020b).

 

Metaphire houlleti (Perrier, 1872)

(Image 3 b1–b2, Table 1)

Examined material: 49C (CTU-EW.006.01), 25C (CTU-EW.006.06), 26C (CTU-EW.006.11), 10C (CTU-EW.006.19), 3C (CTU-EW.006.27), 9C (CTU-EW.006.45), and 11C (CTU-EW.006.48).

Distribution: Widely distributed in southern Vietnam.

 

Metaphire houlletoides Nguyen, Nguyen, Lam & Nguyen, 2020

(Image 4 b1–b2, Table 1)

Examined material: 1C (CTU-EW.180.h01) and 3C (CTU-EW.180.p02); data in Table 1.

Distribution: Binh Phuoc (Loc Ninh, Dong Phu, Bu Gia Map NP, Bu Dang).

Remarks: The species is fairly similar to M. houlleti (Perrier, 1872), however, it is characterized by having two pairs of spermathecal pores in 7/8/9 and smaller size (Nguyen et al. 2020b).

 

Metaphire malayanoides Nguyen & Lam, 2017

(Image 3 c1–c2, Table 1)

Examined material: 1C (CTU-EW.084.h01), 8C (CTU-EW.084.p02), 5C (CTU-EW.084.p03), 16C (CTU-EW.084.04), 31C (CTU-EW.084.05), 14C (CTU-EW.084.06), and 34C (CTU-EW.084.07); data in Table 1.

Distribution: Dong Nai (Vinh Cuu, Dinh Quan, Thong Nhat, Trang Bom).

Remarks: The species is closely similar to M. malayana (Beddard, 1900), however, it is recognized by having presence of genital markings in intersegmental furrows (from 19/20 to 26/27), first dorsal pore in 12/13, and separated testes sacs (Nguyen & Lam 2017).

 

Metaphire mangophiloides Nguyen & Le, 2015

(Image 3 d1–d2, Table 1)

Examined material: 1C (CTU-EW.082.h01) and 1C (CTU-EW.082.p02); data in Table 1.

Distribution: Dong Nai (Vinh Cuu).

Remarks: The species is fairly similar to M. easupana (Thai & Huynh, 1993) but it is characterized by having spermathecal pores in 5/6 and polythecate (Nguyen et al. 2015a).

 

 Metaphire neoexilis (Thai & Samphon, 1988)

(Image 3 e1–e2, Table 1)

Examined material: 32A (CTU-EW.085.01), 13A (CTU-EW.085.02), 3A (CTU-EW.085.03), and 3A (CTU-EW.085.04); data in Table 1.

Distribution: Dong Nai (Long Thanh, Cam My); Binh Duong (Dau Tieng, Phu Giao).

Remarks: The present population has slight difference from the original description of Thai & Samphon (1988) in genital markings in xviii and male pores in xix.

 

Metaphire pacseana (Thai & Samphon, 1988)

(Image 3 f1–f2, Table 1)

Examined material: 6C (CTU-EW.083.01), 4C (CTU-EW.083.03), 3C (CTU-EW.083.07), and 6C (CTU-EW.083.14); data in Table 1.

Distribution: Dong Nai (Long Thanh, Nhon Trach); Binh Duong (Bac Tan Uyen, Ben Cat, Dau Tieng, Bau Bang); Binh Phuoc (Hon Quan); Ho Chi Minh City (Cu Chi); Tay Ninh (Go Dau, Duong Minh Chau, Ba Den Mts).

Remarks: The populations collected in Ba Den Mountain (Tay Ninh province) and Phu Giao (Binh Duong province) lack genital markings while others have two pairs in 17/18 and 18/19 as in the original description.

 

Metaphire peguana peguana (Rosa, 1890)

(Image 3 g1–g2, Table 1)

Examined material: 5C (CTU-EW.009.02), 15C (CTU-EW.009.03), 3C (CTU-EW.009.05), 13C (CTU-EW.009.07), and 16C (CTU-EW.009.14); data in Table 1.

Distribution: Dong Nai (Vinh Cuu, Xuan Loc, Nhon Trach, Long Thanh); Ba Ria-Vung Tau (Tan Thanh); Binh Duong (Bac Tan Uyen, Phu Giao, Ben Cat); Binh Phuoc (Chon Thanh); Ho Chi Minh City (Can Gio, Nha Be, Binh Chanh, Hoc Mon, Cu Chi).

Remarks: The species is somewhat similar to M. bahli (Gates, 1945), but is characterized by having large disc-shaped genital markings and unconcave male region.

 

Metaphire planata (Gates, 1926)

(Image 3 h1–h2, Table 1)

Examined material: 9C (CTU-EW.016.04), 11C (CTU-EW.016.05), 11C (CTU-EW.016.10), 8C (CTU-EW.016.15), 31C (CTU-EW.016.20), 12C (CTU-EW.016.36), and 9C (CTU-EW.016.39); data in Table 1.

Distribution: Widely distributed in southern Vietnam, but more commonly found in grey soils of deltas.

Remarks: The species was erroneously identified as M. californica (Kinberg, 1867), but corrected by Nguyen et al. (2020).  M. planata differs from M. californica in having spermathecal pores in 5/6/7, genital marking present in the spermathecal region associated with saccular accessory glands internally, simple intestinal caeca, separated testes sacs, and smaller size.  It is noted that the preservation code CTU-EW.005 (for M. californica) would be changed to CTU-EW.016 (for M. planata).

 

 Metaphire planatoides Nguyen, Nguyen, Lam & Nguyen, 2020

(Image 4 c1–c2, Table 1)

Examined material: 1C (CTU-EW.171.h01) and 2C (CTU-EW.171.p02); data in Table 1.

Distribution: Ba Ria-Vung Tau (Minh Dam Mts).

Remarks: The species is closely similar to M. planata (Gates, 1926), but it is distinguished by lacking of genital markings and accessory glands, having waved diverticula, connecting testes sacs, and smaller size (Nguyen et al. 2020b).

 

Metaphire posthuma (Vaillant, 1868)

(Image 3 i1–i2, Table 1)

Examined material: 10C (CTU-EW.011.01) and 19C (CTU-EW.011.03); data in Table 1.

Distribution: Dong Nai (Xuan Loc); Binh Duong (Dau Tieng, Phu Giao); Ho Chi Minh City (Can Gio, Hoc Mon, Cu Chi); Tay Ninh (Tan Chau).

 

Metaphire setosa Nguyen, Nguyen, Lam & Nguyen, 2020

(Image 4 d1–d2, Table 1)

Examined material: 1C (CTU-EW.179.h01), and 6C (CTU-EW.179.p02); data in Table 1.

Distribution: Binh Phuoc (Hon Quan, Chon Thanh).

Remarks: The species has very unique morphology characters among known Metaphire species, with regard to its saddle-shaped clitellum and setal arrangement in two rings (Nguyen et al. 2020b).

 

Metaphire songbeensis Nguyen, Nguyen, Lam & Nguyen, 2020

(Image 4 e1–e2, Table 1)

Examined material: 1C (CTU-EW.176.h01), 9C (CTU-EW.176.p02), 13C (CTU-EW.176.03), and 8C (CTU-EW.176.04); data in Table 1.

Distribution: Binh Duong (Dau Tieng, Di An, Ben Cat, Bau Bang); Binh Phuoc (Loc Ninh, Chon Thanh, Dong Xoai, Dong Phu, Phu Rieng, Bu Dang, Phuc Long, Bu Gia Map, Bu Dop).

Remarks: The species is fairly similar to M. posthuma (Vaillant, 1868), but it is recognized by having spermathecal pores in the dorsum, first dorsal pore in 9/10, and ventrally connected testes sacs.  There are two morphological forms.  The first form found in Binh Duong Province has spermathecal pores located closely to the mid-dorsal line and four pairs of genital markings in the male region.  The other form has spermathecal pores located laterodorsally and  more than four pairs of genital markings (Nguyen et al. 2020b).

 

Metaphire xuanlocensis Nguyen & Lam, 2017

(Image 3 j1–j2, Table 1)

Examined material: 1C (CTU-EW.086.h01), 9C (CTU-EW.086.p02), 17C  (CTU-EW.086.03), 6C (CTU-EW.086.04), 12C (CTU-EW.086.05), and 6C (CTU-EW.086.06); data in Table 1.

Distribution: Dong Nai (Xuan Loc, Cam My); Ba Ria-Vung Tau (Ba Ria City, Xuyen Moc, Chau Duc).

Remarks: The species is fairly similar to M. phaluongana (Do & Huynh, 1992), but it is distinguished by having a pair of genital markings in xviii, separated testes sacs, and presence of penial seta (Nguyen & Lam 2017).

 

Genus Pheretima Kinberg, 1867

Pheretima vungtauensis Nguyen, Nguyen & Nguyen, 2018

(Image 4 l1–l2, Table 1)

Examined material: 1C (CTU-EW.166.h01), 2C (CTU-EW.166.p02), 1C (CTU-EW.166.p03), 1C (CTU-EW.166.p04), 2C (CTU-EW.166.p05), 1C (CTU-EW.166.p06), and 1C (CTU-EW.166.p07); data in Table 1.

Distribution: Ba Ria-Vung Tau (Chau Duc, Tan Thanh).

Remarks: The species is closely related to M. houlleti (Perrier, 1872), it is but specialized by the presence of micronephridia attached onto the spermathecal ducts (Nguyen et al. 2018).  Currently, Pheretima vungtauensis is known as the only species of genus Pheretima sensu stricto found in Vietnam.

 

Genus Polypheretima Michaelsen, 1934

Polypheretima cattienensis Nguyen, Tran & Nguyen, 2015

(Image 4 f1–f2, Table 1)

Examined material: 1C (CTU-EW.040.h01), 6C (CTU-EW.040.p02), and 6C (CTU-EW.040.03); data in Table 1.

Distribution: Dong Nai (Cat Tien NP).

Remarks: The species is similar to Po. aringeana (Beddard, 1900), but it is distinguished by lacking of genital markings, presence of seminal chambers, and the strongly coelomic copulatory pouches (Nguyen et al. 2015b).

 

Polypheretima cordata Nguyen, Tran & Nguyen, 2015

(Image 4 h1–h2, Table 1)

Examined material: 1C (CTU-EW.042.h01), 7C (CTU-EW.042.p02), 4C (CTU-EW.042.03), 7C (CTU-EW.042.04), 4C (CTU-EW.042.05), 4C (CTU-EW.042.06), 4C (CTU-EW.042.07), and  4C (CTU-EW.042.08); data in Table 1.

Distribution: Dong Nai (Vinh Cuu, Tan Phu, Trang Bom, Dinh Quan); Binh Phuoc (Dong Phu, Bu Dang, Bu Gia Map, Loc Ninh).

Remarks: The species is closely similar to Po. grandisetosa (Thai, 1996), but it is specialized by number of spermathecal pores (one pair in 5/6, 2 pairs in 6/7 or a pair per segment (found in Binh Phuoc Province)), holandry, presence of copulatory pouches, and absence of stout setae in the dorsum (Nguyen et al. 2015b).

 

Polypheretima elongata (Perrier, 1872)

(Image 4 j1, Table 1)

Examined material: 4C (CTU-EW.026.02); data in Table 1.

Distribution: Ho Chi Minh City (Binh Chanh).

Remarks: This is the first record of the species in the southeastern part of Vietnam, although it is widely distributed in the Mekong Delta (Nguyen 2014).

 

Polypheretima militium Nguyen, Tran & Nguyen, 2015

(Image 4 i1–i2, Table 1)

Examined material: 1C (CTU-EW.041.h01), 6C (CTU-EW.041.p02), 3C (CTU-EW.041.03), and 5C (CTU-EW.041.04); data in Table 1.

Distribution: Dong Nai (Vinh Cuu).

Remarks: The species is somewhat similar to Po. colonensis (Thai, 1996), but it is identified by holandry, polythecate, first dorsal pore in 12/13 or 13/14, and intestinal swelling at xv (Nguyen et al. 2015b).

 

Family MONILIGASTRIDAE Claus, 1880

Genus Drawida Michaelsen, 1900

Drawida beddardi (Rosa, 1890)

(Image 1 b1–n2, Table 1)

Examined material: 4C (CTU-EW.031.02) and 7C (CTU-EW.131.04); data for samples were shown in table 1.

Distribution: Binh Phuoc (Tan Thanh, Bu Dang); Binh Duong (Phu Giao, Dau Tieng) (Nguyen 2014; Nguyen et al. 2015).

 

Family OCNERODRILIDAE Beddard, 1891

Genus Eukerria Michaelsen, 1935

Eukerria saltensis (Beddard, 1895)

(Image 1 c1, Table 1)

Examined material: 8C (CTU-EW.182.01), 7C (CTU-EW.182.02), 7C (CTU-EW.182.03), 8C (CTU-EW.182.04), 29C (CTU-EW.182.05), 16C (CTU-EW.182.06), and 20C (CTU-EW.182.07); data in Table 1.

Distribution: Binh Duong (Thu Dau Mot); Binh Phuoc (Chon Thanh, Bu Dang, Bu Gia Map); Ho Chi Minh City (Can Gio, Nha Be, Binh Chanh); Tay Ninh (Tay Ninh City).

 

Family OCTOCHAETIDAE Gates, 1959

Genus Dichogaster Beddard, 1888

Dichogaster affinis Michaelsen, 1890

(Image 1 d1–d2, Table 1)

Examined material: 16C (CTU-EW.033.01) and 3C (CTU-EW.033.02); data in Table 1.

Distribution: Ho Chi Minh City (Can Gio); Tay Ninh (Ba Den Mts, Trang Bang).

Remarks: The species was recorded for the first time in southeastern Vietnam.  It was usually found along with Dichogaster bolaui in soils of roadside or fallow lands.

 

Dichogaster bolaui (Michaelsen, 1891)

(Image 1 f1–f2, Table 1)

Examined material: 5C (CTU-EW.035.03), 20C (CTU-EW.035.04), 20C (CTU-EW.035.08), 11C (CTU-EW.035.09), and 5C (CTU-EW.035.11); data in Table 1.

Distribution: Ba Ria-Vung Tau (Ba Ria City, Tan Thanh); Dong Nai (Cam My); Binh Phuoc (Bu Gia Map NP); Ho Chi Minh City (Can Gio, Hoc Mon, Binh Chanh).

Remarks: It was very common in southeastern Vietnam, especially in moist soils.

 

Family RHINODRILIDAE Benham, 1890

Genus Pontoscolex Schmarda, 1861

Pontoscolex corethrurus (Müller, 1857)

(Image 1 e1–e2, Table 1)

Examined material: 31C (CTU-EW.001.01), 5C (CTU-EW.001.11), 69C (CTU-EW.001.22), 19C (CTU-EW.001.29), 27C (CTU-EW.001.44), and 21C (CTU-EW.001.45); data in Table 1.

Distribution: Very commonly distributed in Vietnam.

Remarks: The species was known to be native to the South America region, but wide spread over the world (Brown et al. 2006).  In Vietnam, this species has been known widely in all habitats except natural forests in high mountains.

 

 

 

Table 1. The collection of earthworm samples from southeastern Vietnam.

No.

Species names and label codes

Number of Specimen

GPS Coordinates

Location

Date

Collector

Latitude (North)

Longitude (East)

1

Glyphidrilus papillatus (Rosa, 1890)

 

 

 

 

CTU-EW.030.02

2C

10.487778

107.251111

Dat Do, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.030.04

3C

10.913889

106.566111

Hoc Mon, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

2

Lampito mauritii Kinberg, 1867

 

 

 

 

CTU-EW.002.01

27C

10.792778

107.525556

Xuan Loc, Dong Nai

x.2012

Thang V. Nguyen

 

CTU-EW.002.07

13C

10.464167

107.276944

Dat Do, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.002.11

6C

11.429167

106.548333

Chon Thanh, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.002.13

9C

11.412500

106.412778

Dau Tieng, Binh Duong

x.2017

Nam Q. Nguyen

 

CTU-EW.002.27

46C

10.691667

106.603056

Binh Chanh, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.002.32

21C

11.077500

106.402222

Trang Bang, Tay Ninh

ix.2019

Nam Q. Nguyen

3

Perionyx excavatus Perrier, 1872

 

 

 

 

CTU-EW.003.02

1C

10.727222

106.827222

Nhon Trach, Dong Nai

x.2016

Nam Q. Nguyen

 

CTU-EW.003.03

1C

11.333611

106.746389

Phu Giao, Binh Duong

x.2017

Nam Q. Nguyen

4

Amynthas dorsomorrioides Nguyen & Nguyen, 2020

 

 

 

CTU-EW.174.h01

1C

10.511111

107.126944

Dinh Mts., Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.174.p02

2C

10.405833

107.271667

Minh Dam Mts., Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

IEBR-EW.174.p02

2C

10.405833

107.271667

Minh Dam Mts., Ba Ria Vung Tau

x.2016

Hau P. Nguyen

5

Amynthas exiguus austrinus (Gates, 1932)

 

 

 

 

CTU-EW.057.01

4C

11.142778

107.225556

Dinh Quan, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.057.02

5C

10.994444

107.151389

Thong Nhat, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.057.03

14C

11.258889

107.065833

Vinh Cuu, Dong Nai

x.2013

Trong C. Duong

 

CTU-EW.057.04

8C

11.809444

107.067500

Bu Dang, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.057.05

8C

12.192778

107.206944

Bu Gia Map NP, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.057.11

11C

11.390556

106.155278

Ba Den Mts., Tay Ninh

ix.2019

Nam Q. Nguyen

6

Amynthas longiprostaticus Nguyen & Lam, 2020

 

 

 

 

CTU-EW.088.h01

1C

11.425000

107.428333

Cat Tien NP, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.088.p02

5C

11.425000

107.428333

Cat Tien NP, Dong Nai

x.2013

Nhan V. Le

 

IEBR-EW.088.p02

4C

11.425000

107.428333

Cat Tien NP, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.088.03

30C

11.425000

107.428333

Cat Tien NP, Dong Nai

x.2013

Nhan V. Le

 

IEBR-EW.088.03

17C

11.425000

107.428333

Cat Tien NP, Dong Nai

x.2013

Nhan V. Le

7

Amynthas minhdam Nguyen & Tran, 2020

 

 

 

 

CTU-EW.168.h01

1C

10.405556

107.271667

Minh Dam Mts., Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.168.p02

1C

10.405556

107.271667

Minh Dam Mts., Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.168.p03

3C

10.405556

107.271667

Minh Dam Mts., Ba Ria Vung Tau

x.2019

Dang H. Lam

 

IEBR-EW.168.p03

2C

10.405556

107.271667

Minh Dam Mts., Ba Ria Vung Tau

x.2019

Dang H. Lam

8

Amynthas ocularius Nguyen & Lam, 2020

 

 

 

 

CTU-EW.167.h01

1C

10.547500

107.512778

Binh Chau Phuoc Buu NR, Ba Ria Vung Tau

x.2016

Ai T. Truong

 

CTU-EW.167.p02

2C

10.547500

107.512778

Binh Chau Phuoc Buu NR, Ba Ria Vung Tau

x.2016

Ai T. Truong

 

CTU-EW.167.p03

3C

10.547500

107.512778

Binh Chau Phuoc Buu NR, Ba Ria Vung Tau

x.2019

Dang H. Lam

 

IEBR-EW.167.p03

2C

10.547500

107.512778

Binh Chau Phuoc Buu NR, Ba Ria Vung Tau

x.2019

Dang H. Lam

9

Amynthas polychaetiferus (Thai, 1984)

 

 

 

 

CTU-EW.008.01

29C

11.331944

107.157778

Vinh Cuu, Dong Nai

x.2012

Trong C. Duong

 

CTU-EW.008.04

10C

10.898611

107.021667

Trang Bom, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.008.07

11C

10.803056

107.225833

Cam My, Dong Nai

x.2014

Nhan V. Le

 

CTU-EW.008.10

20C

10.646111

107.458333

Xuyen Moc, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.008.18

10C

11.798056

106.933889

Phu Rieng, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.008.21

6C

11.050000

106.788889

Tan Uyen, Binh Duong

x.2017

Nam Q. Nguyen

 

CTU-EW.008.24

2C

11.077500

106.400000

Go Dau, Tay Ninh

ix.2019

Nam Q. Nguyen

10

Metaphire anomala (Michaelsen, 1907)

 

 

 

 

CTU-EW.020.06

11C

10.921667

107.076111

Trang Bom, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.020.07

7C

11.434444

107.428889

Tan Phu, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.020.13

10C

10.525833

107.162222

Ba Ria City, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.020.14

8C

11.798056

106.933889

Phu Rieng, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.020.21

20C

11.386944

106.143056

Tay Ninh City, Tay Ninh

ix.2019

Nam Q. Nguyen

11

Metaphire bahli (Gates, 1945)

 

 

 

 

CTU-EW.004.01

30C

11.231389

107.381944

Dinh Quan, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.004.02

30C

10.837500

107.541111

Xuan Loc, Dong Nai

x.2012

Thang V. Nguyen

 

CTU-EW.004.03

22C

11.312222

107.394722

Tan Phu, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.004.04

16C

11.018333

106.953889

Vinh Cuu, Dong Nai

ix.2012

Trong C. Duong

 

CTU-EW.004.19

28C

10.639167

107.085556

Tan Thanh, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.004.24

19C

11.429167

106.548333

Chon Thanh, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.004.25

20C

10.942778

106.772500

Di An, Binh Duong

x.2017

Nam Q. Nguyen

 

CTU-EW.004.54

39C

10.387500

106.912500

Can Gio, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.004.62

30C

11.382778

106.200000

Duong Minh Chau, Tay Ninh

ix.2019

Nam Q. Nguyen

12

Metaphire bariaensis Nguyen, Nguyen, Lam & Nguyen, 2020

 

 

 

CTU-EW.169.h01

1C

10.593333

107.113889

Bao Quang Mts., Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.169.p02

2C

10.593333

107.113889

Bao Quang Mts., Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.169.p03

3C

10.639167

107.085556

Ba Ria City, Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.169.04

15C

10.525833

107.162222

Tan Thanh, Ba Ria Vung Tau

x.2019

Nam Q. Nguyen

13

Metaphire cf. campanulata (Rosa, 1890)

 

 

 

 

CTU-EW.018.01

17C

11.425278

107.428611

Tan Phu, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.018.09

14C

10.666667

107.248333

Chau Duc, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.018.11

14C

11.527778

106.916667

Dong Xoai, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.018.20

25C

11.050000

106.789167

Tan Uyen, Binh Duong

x.2017

Nam Q. Nguyen

 

CTU-EW.018.34

4C

11.021389

106.555000

Cu Chi, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.018.36

8C

11.382778

106.200000

Duong Minh Chau, Tay Ninh

ix.2019

Nam Q. Nguyen

14

Metaphire easupana (Thai & Huynh, 1993)

 

 

 

 

CTU-EW.012.04

5C

11.160000

107.314444

Dinh Quan, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.012.05

35C

10.944167

107.383611

Xuan Loc, Dong Nai

x.2012

Thang V. Nguyen

 

CTU-EW.012.10

10C

11.018889

106.877500

Vinh Cuu, Dong Nai

ix.2012

Trong C. Duong

 

CTU-EW.012.17

25C

10.404167

107.267778

Minh Dam Mts., Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.012.26

23C

11.390556

106.155278

Ba Den Mts., Tay Ninh

x.2019

Nam Q. Nguyen

15

Metaphire grandiverticulata Nguyen & Lam, 2017

 

 

 

CTU-EW.089.h01

1C

10.741389

106.975278

Long Thanh, Dong Nai

x.2014

Nhan V. Le

 

CTU-EW.089.p02

9C

10.741389

106.975278

Long Thanh, Dong Nai

x.2014

Nhan V. Le

 

CTU-EW.089.03

13C

10.741389

106.975278

Long Thanh, Dong Nai

x.2014

Nhan V. Le

 

CTU-EW.089.04

24C

10.913889

106.566111

Hoc Mon, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

16

Metaphire haui Nguyen, Nguyen, Lam & Nguyen, 2020

 

 

 

CTU-EW.172.h01

1C

10.525833

107.162222

Ba Ria City, Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.172.p02

4C

10.525833

107.162222

Ba Ria City, Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.172.p03

2C

10.499444

107.141944

Ba Ria City, Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.172.p04

4A

10.525833

107.162222

Tan Thanh, Ba Ria Vung Tau

x.2016

Hau P. Nguyen

17

Metaphire houlleti (Perrier, 1872)

 

 

 

 

CTU-EW.006.01

49C

11.089722

107.035833

Vinh Cuu, Dong Nai

x.2012

Trong C. Duong

 

CTU-EW.006.06

25C

11.425278

107.428611

Tan Phu, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.006.11

26C

10.651667

107.240833

Chau Duc, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.006.19

10C

12.057222

107.127500

Bu Gia Map, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.006.27

3C

11.333611

106.746389

Phu Giao, Binh Duong

x.2017

Nam Q. Nguyen

 

CTU-EW.006.45

9C

10.868333

106.548889

Hoc Mon, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.006.48

11C

11.382778

106.200000

Duong Minh Chau, Tay Ninh

ix.2019

Nam Q. Nguyen

18

Metaphire houlletoides Nguyen, Nguyen, Lam & Nguyen, 2020

 

 

 

CTU-EW.180.h01

1C

11.468611

107.000833

Dong Phu, Binh Phuoc

x.2017

Tien T. H. Luong

 

CTU-EW.180.p02

3C

11.468611

107.000833

Dong Phu, Binh Phuoc

x.2017

Tien T. H. Luong

19

Metaphire malayanoides Nguyen & Lam, 2017

 

 

 

 

CTU-EW.084.h01

1C

11.142778

107.225556

Dinh Quan, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.084.p02

8C

11.142778

107.225556

Dinh Quan, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.084.p03

5C

10.994444

107.152222

Thong Nhat, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.084.04

16C

11.142778

107.225556

Dinh Quan, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.084.05

31C

10.994444

107.152222

Thong Nhat, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.084.06

14C

11.111111

107.053333

Vinh Cuu, Dong Nai

x.2012

Trong C. Duong

 

CTU-EW.084.07

34C

11.231389

107.381944

Dinh Quan, Dong Nai

x.2013

Nhan V. Le

20

Metaphire mangophiloides Nguyen & Le, 2015

 

 

 

 

CTU-EW.082.h01

1C

11.265000

107.064444

Vinh Cuu, Dong Nai

xi.2012

Trong C. Duong

 

CTU-EW.082.p02

1C

11.265000

107.064444

Vinh Cuu, Dong Nai

xi.2012

Trong C. Duong

21

Metaphire neoexilis (Thai & Samphon, 1988)

 

 

 

 

CTU-EW.085.01

32A

10.705833

106.825000

Nhon Trach, Dong Nai

x.2014

Nhan V. Le

 

CTU-EW.085.02

13A

10.705833

106.825000

Nhon Trach, Dong Nai

x.2014

Nhan V. Le

 

CTU-EW.085.03

3A

10.973889

106.568333

Cu Chi, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.085.04

3A

11.077500

106.400000

Go Dau, Tay Ninh

ix.2019

Nam Q. Nguyen

22

Metaphire pacseana (Thai & Samphon, 1988)

 

 

 

 

CTU-EW.083.01

6C

10.790278

107.036389

Long Thanh, Dong Nai

x.2014

Nhan V. Le

 

CTU-EW.083.03

4C

11.624444

106.651667

Hon Quan, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.083.07

3C

11.294722

106.406111

Dau Tieng, Binh Duong

x.2017

Nam Q. Nguyen

 

CTU-EW.083.14

6C

11.077500

106.400000

Go Dau, Tay Ninh

ix.2019

Nam Q. Nguyen

23

Metaphire peguana peguana (Rosa, 1890)

 

 

 

 

CTU-EW.009.02

5C

10.944167

107.383611

Xuan Loc, Dong Nai

ix.2012

Thang V. Nguyen

 

CTU-EW.009.03

15C

11.089722

107.035833

Vinh Cuu, Dong Nai

x.2012

Trong C. Duong

 

CTU-EW.009.05

3C

10.499167

107.102778

Tan Thanh, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.009.07

13C

11.094722

106.841111

Bac Tan Uyen, Binh Duong

x.2017

Nam Q. Nguyen

 

CTU-EW.009.14

16C

11.021389

106.555000

Cu Chi, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

24

Metaphire planata (Gates, 1926)

 

 

 

 

CTU-EW.005.04

9C

11.010278

106.846944

Vinh Cuu, Dong Nai

ix.2012

Trong C. Duong

 

CTU-EW.005.05

11C

10.727500

106.892778

Nhon Trach, Dong Nai

x.2014

Nhan V. Le

 

CTU-EW.005.10

11C

10.643889

107.113889

Tan Thanh, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.005.15

8C

11.429167

106.548333

Chon Thanh, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.005.20

31C

11.419167

106.413611

Dau Tieng, Binh Duong

x.2017

Nam Q. Nguyen

 

CTU-EW.005.36

12C

10.558889

106.821111

Can Gio, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.005.39

9C

11.077500

106.400000

Trang Bang, Tay Ninh

ix.2019

Nam Q. Nguyen

25

Metaphire planatoides Nguyen, Nguyen, Lam & Nguyen, 2020

 

 

 

CTU-EW.171.h01

1C

10.405833

107.271667

Minh Dam Mts., Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.171.p02

2C

10.405833

107.271667

Minh Dam Mts., Ba Ria Vung Tau

x.2016

Hau P. Nguyen

26

Metaphire posthuma (Vaillant, 1868)

 

 

 

 

CTU-EW.011.01

10C

10.780000

107.495278

Xuan Loc, Dong Nai

x.2012

Thang V. Nguyen

 

CTU-EW.011.03

19C

10.387500

106.912500

Can Gio, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

27

Metaphire setosa Nguyen, Nguyen, Lam & Nguyen, 2020

 

 

 

CTU-EW.179.h01

1C

11.567222

106.596111

Hon Quan, Binh Phuoc

x.2017

Tien T. H. Luong

 

CTU-EW.179.p02

6C

11.567222

106.596111

Hon Quan, Binh Phuoc

x.2017

Tien T. H. Luong

28

Metaphire songbeensis Nguyen, Nguyen, Lam & Nguyen, 2020

 

 

 

CTU-EW.176.h01

1C

11.760833

106.577222

Loc Ninh, Binh Phuoc

x.2017

Tien T. H. Luong

 

CTU-EW.176.p02

9C

11.760833

106.577222

Loc Ninh, Binh Phuoc

x.2017

Tien T. H. Luong

 

CTU-EW.176.03

13C

11.760833

106.577222

Loc Ninh, Binh Phuoc

x.2017

Tien T. H. Luong

 

CTU-EW.176.04

8C

11.294722

106.406111

Dau Tieng, Binh Duong

x.2017

Na S. Dinh

29

Metaphire xuanlocensis Nguyen & Lam, 2017

 

 

 

 

CTU-EW.086.h01

1C

10.815833

107.542222

Xuan Loc, Dong Nai

ix.2012

Thang V. Nguyen

 

CTU-EW.086.p02

9C

10.815833

107.542222

Xuan Loc, Dong Nai

ix.2012

Thang V. Nguyen

 

CTU-EW.086.03

17C

10.712500

107.324722

Cam My, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.086.04

6C

10.654444

107.264722

Chau Duc, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.086.05

12C

10.606111

107.438611

Xuyen Moc, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.086.06

6C

10.646111

107.458333

Chau Duc, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

30

Pheretima vungtauensis Nguyen, Nguyen & Nguyen, 2018

 

 

 

CTU-EW.166.h01

1C

10.749167

107.243056

Chau Duc, Ba Ria Vung Tau

x.2016

Ai T. Truong

 

CTU-EW.166.p02

2C

10.749167

107.243056

Chau Duc, Ba Ria Vung Tau

x.2016

Ai T. Truong

 

CTU-EW.166.p03

1C

10.661667

107.156389

Chau Duc, Ba Ria Vung Tau

x.2016

Ai T. Truong

 

CTU-EW.166.p04

1C

10.640278

107.350000

Chau Duc, Ba Ria Vung Tau

x.2016

Ai T. Truong

 

CTU-EW.166.p05

2C

10.643889

107.113889

Tan Thanh, Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.166.p06

1C

10.485833

107.181667

Tan Thanh, Ba Ria Vung Tau

x.2016

Hau P. Nguyen

 

CTU-EW.166.p07

1C

10.594167

107.123333

Tan Thanh, Ba Ria Vung Tau

x.2016

Hau P. Nguyen

31

Polypheretima cattienensis Nguyen, Tran & Nguyen, 2015

 

 

 

CTU-EW.040.h01

1C

11.425000

107.428333

Tan Phu, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.040.p02

6C

11.425000

107.428333

Tan Phu, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.040.03

6C

11.425278

107.428611

Tan Phu, Dong Nai

xi.2019

Dang H. Lam

32

Polypheretima cordata Nguyen, Tran & Nguyen, 2015

 

 

 

CTU-EW.042.h01

1C

11.113611

107.052778

Vinh Cuu, Dong Nai

x.2013

Trong C. Duong

 

CTU-EW.042.p02

7C

11.113611

107.052778

Vinh Cuu, Dong Nai

x.2013

Trong C. Duong

 

CTU-EW.042.03

4C

11.428333

107.427222

Tan Phu, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.042.04

7C

11.113611

107.052778

Vinh Cuu, Dong Nai

x.2013

Trong C. Duong

 

CTU-EW.042.05

4C

10.947778

107.018333

Dinh Quan, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.042.06

4C

11.511667

106.986667

Dong Phu, Binh Phuoc

x.2013.

Nhan V. Le

 

CTU-EW.042.07

4C

12.191111

107.203333

Bu Gia Map, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.042.08

4C

11.527778

106.916667

Dong Xoai, Binh Phuoc

x.2017

Nam Q. Nguyen

33

Polypheretima elongata (Perrier, 1872)

 

 

 

 

CTU-EW.026.02

4C

10.835278

106.526944

Binh Chanh, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

34

Polypheretima militium Nguyen, Tran & Nguyen, 2015

 

 

 

CTU-EW.041.h01

1C

11.142500

107.014444

Vinh Cuu, Dong Nai

x.2013

Trong C. Duong

 

CTU-EW.041.p02

6C

11.142500

107.014444

Vinh Cuu, Dong Nai

x.2013

Trong C. Duong

 

CTU-EW.041.03

3C

11.142500

107.014444

Vinh Cuu, Dong Nai

x.2013

Trong C. Duong

 

CTU-EW.041.04

5C

11.113611

107.053333

Vinh Cuu, Dong Nai

x.2019

Nam Q. Nguyen

35

Drawida beddardi (Rosa, 1890)

 

 

 

 

CTU-EW.031.02

4C

11.925000

106.726944

Bu Dop, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.031.04

7C

11.433056

106.385278

Dau Tieng, Binh Duong

x.2014

Nhi T. N. Nguyen

36

Eukerria saltensis (Beddard, 1895)

 

 

 

 

CTU-EW.182.01

8C

12.057222

107.127500

Bu Gia Map, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.182.02

7C

11.024722

106.621944

Thu Dau Mot, Binh Duong

x.2017

Nam Q. Nguyen

 

CTU-EW.182.03

7C

10.387500

106.912500

Can Gio, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.182.04

8C

10.691389

106.660000

Binh Chanh, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.182.05

29C

10.702778

106.573889

Binh Chanh, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.182.06

16C

11.390556

106.155278

Tay Ninh City, Tay Ninh

ix.2019

Nam Q. Nguyen

 

CTU-EW.182.07

20C

11.382778

106.137778

Tay Ninh City, Tay Ninh

ix.2019

Nam Q. Nguyen

37

Dichogaster affinis (Michaelsen, 1890)

 

 

 

 

CTU-EW.033.01

16C

10.551944

106.779722

Can Gio, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.033.02

3C

11.077500

106.400000

Trang Bang, Tay Ninh

ix.2019

Nam Q. Nguyen

38

Dichogaster bolaui (Michaelsen, 1891)

 

 

 

 

CTU-EW.035.03

5C

10.639167

107.085556

Tan Thanh, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.035.04

20C

12.191111

107.203333

Bu Gia Map, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.035.08

20C

10.749722

107.349722

Cam My, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.035.09

11C

10.477222

106.879444

Can Gio, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.035.11

5C

11.390556

106.155278

Tay Ninh City, Tay Ninh

ix.2019

Nam Q. Nguyen

39

Pontoscolex corethrurus (Müller, 1857)

 

 

 

 

CTU-EW.001.01

31C

11.424444

107.435278

Tan Phu, Dong Nai

x.2013

Nhan V. Le

 

CTU-EW.001.11

5C

10.628889

107.112500

Tan Thanh, Ba Ria Vung Tau

x.2016

Nam Q. Nguyen

 

CTU-EW.001.22

69C

11.861111

107.025556

Bu Dang, Binh Phuoc

x.2017

Nam Q. Nguyen

 

CTU-EW.001.29

19C

11.050000

106.788889

Tan Uyen, Binh Duong

x.2017

Nam Q. Nguyen

 

CTU-EW.001.44

27C

10.702778

106.573889

Binh Chanh, Ho Chi Minh City

ix.2019

Nam Q. Nguyen

 

CTU-EW.001.45

21C

11.371389

106.254722

Duong Minh Chau, Tay Ninh

ix.2019

Nam Q. Nguyen

 

 

 

Key to the earthworm species in southeastern Vietnam

 

1.   – Setae Lumbricine................................................................................................................. 2

       – Setae Perichaetine............................................................................................................... 8

2.   – Clitellum formed from more than one layer of cells................................................................... 3

       – Clitellum formed from a single layer of cells....................................................... Drawida beddardi

3.   – Clitellum annular........................................................................................... Eukerria saltensis

       – Clitellum saddle-shaped........................................................................................................ 4

4.   – Clitellum within 5 segments xiii–xviii................................................................ Pontodrilus litoralis

       – Clitellum within more than 5 segments.................................................................................... 5

5.   – Clitellum within 7 segment xiii–xx. Male pores in xviii................................................................. 6

       – Clitellum within more than 7 segments. Male pore invisible........................................................ 7

6.   – Female pore single. Genital markings absent..................................................... Dichogaster bolaui

       – Female pore paired. Genital marking single in mid-ventral of 8/9.......................... Dichogaster affinis

7.   – Clitellum within 9 segments xiv-xxiii.......................................................... Pontoscolex corethrurus

       – Clitellum within 22 segments xiii–xxxvi......................................................... Gliphidrilus papillatus

8.   – Clitellum within 4 segments xiv–xvii........................................................................................ 9

       – Clitellum within 3 segments xiv–xvi....................................................................................... 10

9.   – Three pairs of spermathecal pores in 6/7/8/9. Bidiverticulate.................................. Lampito mauritii

       – Two pairs of spermathecal pores in 7/8/9. Adiverticulate.................................... Perionyx excavatus

10. – Intestine with a pair of caeca............................................................................................... 11

       – Intestine without caeca....................................................................................................... 38

11. – Copulatory pouches present................................................................................................ 12

       – Copulatory pouches absent.................................................................................................. 32

12. – Nephridia attached onto the spermathecal ducts........................................ Pheretima vungtauensis

       – Spermathecal ducts without nephridia................................................................................... 13

13. – Male pore in xix................................................................................................................. 14

       – Male pore in xviii............................................................................................................... 16

14. – Four pairs of spermathecal pores in lateroventral 5/6/7/8/9. Clitellum annular............................. 15

       – Three pairs of spermathecal pores in 6/7/8/9 dorsally. Clitellum saddle-shaped........ Metaphire setosa

15. – One pair of genital markings in xviii. First dorsal pore in 8/9................................ Metaphire neoexilis

       – Genital markings absent sin the male region. First dorsal pore in 12/13................ Metaphire anomala

16. – Multiple spermathecae per segment..................................................... Metaphire mangophiloides

       – One pair of spermathecae per segment................................................................................. 17

17. – Four pairs of spermathecal pores in 5/6/7/8/9........................................................................ 18

       – Less than four pairs of spermathecal pores............................................................................. 22

18. – Spermathecal pores dorsally.................................................................... Metaphire songbeensis

       – Spermathecal pores not in dorsum........................................................................................ 19

19. – Caeca complex. Genital markings absent in the male region............................. Metaphire bariaensis

       – Caeca simple Genital markings present in the male region......................................................... 20

20. – Genital markings intersegmental in the male region................................... Metaphire malayanoides

       – Genital markings segmental in the male region....................................................................... 21

21. – Two pairs of genital markings in xvii and xix. Septum 8/9 thickened................... Metaphire posthuma

       – One pairs of genital markings in xviii.................................................... Metaphire grandiverticulata

22. – Three pairs of spermathecal pores 6/7/8/9............................................................................. 23

       – Less than three pairs of spermathecal pores........................................................................... 28

23. – Spermathecal pores dorsally............................................................................... Metaphire haui

       – Spermathecal pores not in dorsum........................................................................................ 24

24. – Spermathecal pores laterally. Caeca manicate................................................ Metaphire pacseana

       – Spermathecal pores lateroventrally. Caeca simple................................................................... 25

25. – Genital markings two pairs in 17/18 and 18/19........................................................................ 26

       – Genital markings absent in the male region............................................................................ 27

26. – Genital markings slit-like. Male region strongly concave.......................................... Metaphire bahli

       – Genital markings disc-shaped. Male region not concave........................ Metaphire peguana peguana

27. – First dorsal pore in 11/12. Spermatheca mushroom-shaped...................... Metaphire cf. campanulata

       – First dorsal pore in 9/10. Spermatheca ovoid..................................................... Metaphire houlleti

28. – Two thecal segments. Penial setae absent.............................................................................. 29

       – One thecal segments in 7/8. Penial setae present........................................ Metaphire xuanlocensis

29. – Spermathecal pores in 5/6/7. Caeca manicate................................................ Metaphire easupana

       – Spermathecal pores in 6/7/8 or 7/8/9. Caeca simple................................................................ 30

30. – Spermathecal pores in ở 6/7/8............................................................................................. 31

       – Spermathecal pores in 7/8/9.................................................................... Metaphire houlletoides

31. – Genital markings surrounded, next to spermathecal pores. Accessory glands present Metaphire planata

       – Genital markings absent in both the male and spermatheca regions. Accessory glands absent Metaphire planatoides

32. – Four pairs of spermathecal pores in 5/6/7/8/9........................................................................ 33

       – Less than four pairs of spermathecal pores............................................................................. 35

33. – Setae crowded in ventrad in xix............................................................. Amynthas polychaetiferus

       – Setae in usual position........................................................................................................ 34

34. – Two to three pairs of genital markings in xviii and 18/19;..............................................................

       – One pair of genital markings in 18/19. Genital markings single in vii or ix.... Amynthas exiguus austrinus

       – Three to four pairs of genital markings in xvii, xix and onwards. Genital markings absent in the spermathecal region Amynthas juliani

35. – Three pairs of spermathecal pores in 5/6/7/8................................................... Amynthas ocularius

       – Less than three pairs of spermathecal.................................................................................... 36

36. – Two pairs of spermathecal pores in 5/6/7............................................................................... 37

       – Only one pair of spermathecal pores in 5/6............................................. Amynthas longiprostaticus

37. – Spermathecal pores laterodorsally. One pair of genital markings in xvii. Markings absent in the spermathecal region .....................

          ................................................................................................................................................................... Amynthas dorsomorrioides

       – Spermathecal pores lateroventrally. One pair of genital markings in xviii. One to five genital markings in vi–vii             Amynthas mindam

38. – Three to four pairs of genital markings in xix afterwards............................... Polypheretima elongata

       – Genital markings absent in the male region............................................................................ 39

39. – Multiple spermathecae per segment in vi and vii. Testes sacs connected ventrally......................... 40

       – One pair of spermatheca in vi and two pairs in vii. Testes sacs separated.......... Polypheretima cordata

40. – Seminal chamber present. Male pores crescentic-shaped......................... Polypheretima cattienensis

           – Seminal chamber absent. Male pores round-shaped……………………….Polypheretima militium

 

 

For figures & images - - click here

 

 

REFERENCES

 

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Hendrix, P.F. & P.J. Bohlen (2002). Exotic Earthworm Invasions in North America: Ecological and Policy Implications Expanding global commerce may be increasing the likelihood of exotic earthworm invasions, which could have negative implications for soil processes, other animal and plant spe. BioScience 52(9): 801–811. https://doi.org/10.1641/0006-3568(2002)052[0801:EEIINA]2.0.CO;2

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Nguyen, N.Q., T.V. Nguyen, T.C. Duong, N.V. Le & T.T. Nguyen (2019). Species diversity of earthworms in Dong Nai Province, Vietnam. Tap Chi Sinh Hoc 41: 117–129. https://doi.org/10.15625/0866-7160/v41n2se1

Nguyen, N.T.N. (2014). Species and distribution characteristics of earthworms in Dau Tieng District, Binh Duong Province. Journal of Thu Dau Mot University 5(18): 48–54. http://vci.vnu.edu.vn/upload/15022/pdf/57637a4a7f8b9a19d78b4576.pdf

Nguyen, T.T. (2014). Checklist and some remarks on faunistic characteristics of earthworms in the Mekong Delta, Vietnam. Can Tho University Journal of Science 32: 106–119. https://sj.ctu.edu.vn/ql/docgia/tacgia-9530/baibao-2641/doi-ctu.jvn.2014.116.html

Nguyen, T.T. & D.H. Lam (2017). Three new earthworm species of the genus Metaphire Sims & Easton, 1972 (Oligochaeta, Megascolecidae) from Dong Nai Province, Vietnam. Tạp Chi Sinh Hoc 39(4): 406–415. https://doi.org/10.15625/0866-7160/v39n4.10627

Nguyen, T.T., A.D. Nguyen, B.T.T. Tran & R.J. Blakemore (2016). A comprehensive checklist of earthworm species and subspecies from Vietnam (Annelida: Clitellata: Oligochaeta: Almidae, Eudrilidae, Glossoscolecidae, Lumbricidae, Megascolecidae, Moniligastridae, Ocnerodrilidae, Octochaetidae). Zootaxa 4140(1): 1–92. https://doi.org/10.11646/zootaxa.4140.1.1

Nguyen, T.T., N.Q. Nguyen, D.H. Lam, & A.D. Nguyen (2020b). Six new species of the genus Metaphire Sims & Easton, 1972 (Annelida: Oligochaeta: Megascolecidae) from southeastern Vietnam. Raffles Bulletin of Zoology 68: 220–236. https://doi.org/10.26107/RBZ-2020-0019

Nguyen, T.T., N.Q. Nguyen & A.D. Nguyen (2018). First record of the earthworm genus Pheretima Kinberg, 1867 sensu stricto in Vietnam, with description of a new species (Annelida: Clitellata: Megascolecidae). Zootaxa 4496(1): 251–258. https://doi.org/10.11646/zootaxa.4496.1.20

Nguyen, T.T., N.Q. Nguyen, A.T. Truong, & H.P. Nguyen (2017). Diversity and distribution of earthworms in Ba Ria - Vung Tau province. Can Tho University Journal of Science 53(A): 96–107. https://doi.org/10.22144/ctu.jvn.2017.146

Nguyen, T.T., B.T.T. Tran, D.H. Lam & A.D. Nguyen (2020a). Four new species of Amynthas earthworms in southeastern Vietnam (Annelida, Oligochaeta, Megascolecidae). Zootaxa 4790(2): 277–290. https://doi.org/10.11646/zootaxa.4790.2.5

Nguyen, T.T., B.T.K. Trinh, N.V. Le & A.D. Nguyen (2015a). On the polythecate earthworms of the genus Metaphire (Oligochaeta: Megascolecidae) from Vietnam, with descriptions of three new species. Raffles Bulletin of Zoology 63: 461–470.

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