A new species of Dicranocentroides (Collembola: Paronellidae) from India

Ashis Kumar Hazra 1 & Guru Pada Mandal 2

 

1,2 Zoological Survey of India, Apterygota Section, M-Block, New Alipore, Kolkata, West Bengal 700053, India

1 dr.ashishazra@gmail.com, 2 gpmandal.zsi@gmail.com (corresponding author)

 

 

doi: http://dx.doi.org/10.11609/JoTT.o3584.7547-51 | ZooBank: urn:lsid:zoobank.org:pub:525E36CA-4E7C-4BF1-A614-03E5A1D7599F

 

Editor: Penelope Greenslade, Federation University, Ballarat, Australia. Date of publication: 26 July 2015 (online & print)

 

Manuscript details: Ms # o3584 | Received 12 April 2013 | Final received 06 May 2015 | Finally accepted 30 June 2015

 

Citation: Hazra, A.K. & G.P. Mandal (2015). A new species of Dicranocentroides (Collembola: Paronellidae) from India. Journal of Threatened Taxa 7(9): 7547–7551; http://dx.doi.org/10.11609/JoTT.o3584.7547-51

 

Copyright: © Hazra & Mandal 2015. Creative Commons Attribution 4.0 International License. JoTT allows unrestricted use of this article in any medium, reproduction and distribution by providing adequate credit to the authors and the source of publication.

 

Funding: Zoological Survey of India, Ministry of Environment, Forests & Climate change, Govt. Of India, New Delhi.

 

Competing interests: The authors declare no competing interests.

 

Acknowledgements: We are grateful to Dr. K. Venkatraman, Director, Zoological Survey of India, Kolkata for providing laboratory facilities. Thanks are also due to the staff members of the Apterygota section of the same organization and MoEF, New Delhi, Govt. of India for funding the project.

 

 

Abstract: A new species, Dicranocentroides duduaensis sp. nov., is described from the Dudhwa Tiger Reserve, Uttar Pradesh, India. A key to the Indian species of the genus is also provided.

Keywords: Brushsetae, chaetotaxy, pigment, patterns.

Abbreviations: Ant. - antennae; Th. - thorax; Abd. - abdomen; NZC/ZSI- National Zoological Collection/Zoological Survey of India.

 

 

 

 

The genus Dicranocentroides was established by Imms (1912) with Dicranocentroides fasciculatus Imms, 1912 as its type species. The main characters of this genus include: body with scales, antennae longer than or equal to half the length of trunk, mesothorax not humped, metathorax not strongly bent, eyes 8+8, vertex with macrochaetae, genal and occipital areas of head with three macrochaetae (Mitra, 1993), manubrium without spines, dens with spines, mucro 1.5 times as long as basal width, mucro sharply separated from dens, mucro with more than three teeth. Sexual dimorphisms have been reported in D. fasciculatus Imms (Mitra, 1975). Mitra (1975) synonymised Paronella travancorica Imms, 1912 with Dicranocentroides indica (Handschin, 1929) and this synonymy is confirmed here. A total of five species in this genus are known from India. There are 19 species of Dicranocentroides known from the world. The distribution of the genus outside India is Malaysia, Java, Sumatra and Thailand. Species’ habitats are fallen leaves and grasses, surface soil of dried swamps in evergreen forests.

 

Material and Methods

Specimens were collected by an aspirator and preserved in 70% alcohol. They were cleared in Marc Andre 1 medium. Dark specimens were placed in potassium hydroxide (KOH) to soften the chitin. Softening the chitin is required for 10–15 minutes depending upon the intensity of the pigment. Hoyer’s mounting medium was used for slide-mounting of the specimens. Identification of specimens was with a phase contrast compound microscope following Christiansen & Bellinger (1998). All the specimens examined have been deposited at National Zoological Collection, Zoological Survey of India, Kolkata (NZC/ZSI).

 

 

Dicranocentroides duduaensis sp. nov.

(Images 1–2; Figs. 1–17; Table 1)

urn:lsid:zoobank.org:act:13E6F510-8959-4707-9B93-7797010B6EF3

 

Material examined

Holotype: 457/H14, 15.i.2009, 1 male, Kila Forest Rest House campus, Uttar Pradesh, India (28018’N & 80028’E), Dudhwa Tiger Reserve, Lakhimpur Kheri District, coll. G.P. Mandal.

Paratypes: 458/H14, 15.i.2009, 32 (12 male & 20 female), Kila Forest Rest House campus, Uttar Pradesh, India (28018’N & 80028’E), Dudhwa Tiger Reserve, Lakhimpur Kheri District, coll. G.P. Mandal.

 

Description

Colour pattern: Ground colour of the body deep yellow in alcohol. Ant. I distally with dark pigment rings, rest devoid of pigment. Ant. II entirely with dark pigment, region of subdivision of each segment of antennae non-pigmented (Images 1–2), Ant.I and Ant. II polychaetoic and with brush-like setae (Figs. 1–2), Ant. II covered with more dense setae in comparison to Ant. I, dorsal margin of Ant. III and Ant. IV light blue pigment, tip of Ant. IV with dark pigment apically. Tibiotarsi with bluish violet pigment, inner margin of each femur with longitudinal dark pigment. Th. II centrally devoid of colour pigment, medially and distally with two blue black patches, both patches fused laterally and forming arrow head like-band one on each side, Th. III with two discontinuous patches on each side, medial patches wider and darker, lateral patches with light pigment. Abd.I small dot-like sub-medial blue black pigment on both sides (Fig. 3), Abd. II devoid of any colourpatch, Abd. IV with lateral pigment extended to ventro-laterally with the Abd. III, Abd. IV dorso-medially with vertical dark bluish pigment patches one on each side medially diffused with the large lateral patches and extended posteriorly, bluish terminal end of the Abd. IV with dark bluish patches which extend laterally of Abd.V and base of the manubrium, Abd. VI devoid of any pigment. Characteristic head pigmentation as in Fig. 4.

Clothing: Body clothed with dark brown scales and setae.

Chaetotaxy-head: vertex with V0+V1-7, frontal region with 4+4 setae, sub-dorsal region with 11 setae, ocular region with three macrochaetae, post-ocular region with one macrochaetae, occipital with single macrochaetae (Fig. 5). Cervix of Th. II with several smooth setae, Th. II, III with 32–33/27 macrochaetae. Abd.I with 18, Abd.II, with 8, Abd.III with 2 macrochaetae, Abd.IV medially with transverse row with 13–14 setae and posteriorly with 11+11 setae (Fig. 6). Scales of head, thorax and abdomen are pointed, rounded or truncate and densely covered with striations (Fig. 7).

Head: Pear shaped, two longitudinal parallel rows of ocelli (8+8) covered with dark pigment, G & H ocelli smaller in size than the rest. Antennae as long as trunk of the body, ratio of Ant. segments I–IV as 1.0/1.3–1.0/0.8–1.0/1.4, Ant. IV with apical sense knob and one pin seta with some smooth setae (Fig. 8). Prelabralsetae 4, labral setae 5, 5/4, anterior margin of labrum with 4 tubercles round in shape (Fig. 9).

Thorax: Ratio of Th. segments II–III as 1.0–1.0/0.9. Unguis slightly curved with two external baso-lateral teeth 1+1 on each side of unguis, inner margin of unguis with paired inner basal and pair medial teeth, distal tooth unpaired, unguiculus lanceolate, acuminate, without teeth on outer lamella; inner tibio-tarsal lobe conspicuous , tenent hair well developed, slightly clavate (Fig. 10). Trochanteral organ with about 66 strong, short spines (Fig. 11). Tibiotarsus with variable stout, striated spinous setae on inner lateral margin.

 

 

 

 

Abdomen: Ratio of Abd. segments I–VI as 1.0/1.07–1.0/1.05–1.0/5.5–1.0/0.7–1.0/0.6. Ventral tube long with protrusible vesicle retracted, anterior face anteriorly with several long macrochaetae (Fig. 12), posterior face with short spine like setae as in Fig. 13, rami of retinaculum 4+4 teeth, corpus with a median setae, ratio of manubrium: dens: mucro as 1.0/1.15–1.0/0.5, dens in their inner margin with two rows of closely opposed spines, and stiff, ciliated setae distally (Fig. 14), mucro large with six teeth, lateral tooth long (Fig. 15), outer view of mucronal teeth with light striation (Fig. 16), arrangement of mucronal teeth in other view (Fig. 17). Length without appendages 2.4mm.

 

Ecology

The species was found in large numbers, generally in shady semi-decomposed moist leaf litter in forested regions. It is an active species on the ground in leaf litter of Dudwa Tiger Reserve. The species is abundant in this tropical semi-evergreen forest of upper gangetic alluvial plains. The protection of this habitat will help to conserve the collembolan species.

 

Etymology

The species is named after the Dudhwa Tiger Reserve, Uttar Pradesh locally known as Dudua, which is the type locality.

 

Discussion

The new species is similar to Dicranocentroides gisini Mitra in having pigment on Th.II and without medial pigment on Abd. III, IV and V but differs from D. gisini in the characteristics given in Table 1. The Thai species, Dicranocentroides orientalis Kim, Park, Rojanavongse & Lee, 1999, also has the brush like setae in Ant. I & II but clearly differs from D. duduaensis by absence of colour pigment on Th.II, III; Abd.I, III, IV, V and inner margin of unguis without paired medial teeth.

 

References

 

Christiansen, K.A. & P. Bellinger (1998). The Collembola of North America North of the Rio Grande. A Taxonomic Analysis. Grinnel College, Iowa 1520pp.

Imms, A.D. (1912). On some Collembola from India, Burma and Ceylon, with a catalogue of the Oriental species of the Order. Proceedings of the Zoological Society of London 6: 80–125.

Kim, J.T., K.H. Park, V. Rojanavongse & B.H. Lee (1999). Systematic Study on Collembola (Insecta) from Thailand, I. Eight New Species of Dicranocentroides (Paronellidae) and Lepidocyrtus (Entomobryidae). Natural History Bulletin of the Siam Society 47: 207–224.

Mitra, S.K. (1975). Studies on the genus Dicranocentroides Imms (1912) (Collembola: Entomobryidae: Paronellinae) from India. Records of the Zoological Survey of India 71: 57–95.

Mitra, S.K. (1993). Chaetotaxy, Phylogeny and Biogeography of Paronellinae (Collembola: Entomobryidae). Records of the Zoological Survey of India, Occasional papers 154: 1–100.