Journal of Threatened Taxa | www.threatenedtaxa.org | 26 June 2021 | 13(7): 18925–18932

 

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

https://doi.org/10.11609/jott.5341.13.7.18925-18932

#5341 | Received 16 August 2019 | Final received 02 October 2020 | Finally accepted 27 May 2021

 

 

Re-collection, extended distribution, and amplified description of Vaccinium paucicrenatum Sleumer (Ericaceae) from the Arunachal Himalaya in India

 

Subhasis Panda

 

Angiosperm Taxonomy & Biodiversity Conservation Laboratory, Botany Department, Maulana Azad College, 8, Rafi Ahmed Kidwai Road, Kolkata, West Bengal 700013, India.

bgc.panda@gmail.com

 

 

 

Editor: Anonymity requested.   Date of publication: 26 June 2021 (online & print)

 

Citation: Panda, S. (2021). Re-collection, extended distribution, and amplified description of Vaccinium paucicrenatum Sleumer (Ericaceae) from the Arunachal Himalaya in India. Journal of Threatened Taxa 13(7): 18925–18932. https://doi.org/10.11609/jott.5341.13.7.18925-18932

 

Copyright: © Panda 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: Botanical Survey of India awarded me JRF & SRF to survey this work. Tenure: 1999-2004. There is no specific project.

 

Competing interests: The author declares no competing interests.

 

Acknowledgements: Author is grateful to Dr. M. Sanjappa, former director in Botanical Survey of India for his necessary help during field studies, to the curators and librarians of Central National Herbarium (CAL) and ARUN for their essential help during herbarium and taxonomic literature consultations and to CCF, Itanagar for their kind permission.  Author is also grateful to the principals of Barasat Govt. College and Darjeeling Government College for granting permission for laboratory work.

 

 

 

Abstract: Vaccinium paucicrenatum Sleumer has been re-collected from three different districts of Arunachal Pradesh approximately after 91 years subsequent to I.H. Burkill’s collection (no. 36976, K) from Ripsing of outer Abor Hills (presently a part of East and West Siang districts nearby Pashighat area) of Arunachal Pradesh on 8 March, 1912.   Due to poor description by the earlier workers, the present paper provides amplified description based on field and herbarium data including leaf anatomy (leaf stomata and vein-islets), detailed extended distribution, live and herbarium images and distribution map for easy identification in the field.

 

Keywords: Arunachal Pradesh, leaf anatomy, northeastern India.

 

 

 

The genus Vaccinium L., consisting of about 140 species (Mabberley 2008), is distributed in tropical Asia, Europe, southeastern Africa, Madagascar, and north and south America.  Of these, 28 species are reported to occur in India (Panda & Sanjappa 2014) and are distributed in the eastern Himalaya, northeastern India (except Tripura) and the hill tops of the southern Western Ghats.

vander Kloet et al. (2003), merged Airy Shaw’s new species, Vaccinium setipes, under V. paucicrenatum Sleumer in Vaccinium sect. Aethopus Airy Shaw based on average-linkage dendrogram calculated from raw data for 76 Vaccinium OTU’s (Operational Taxonomic Unit) using the dissimilarity form of Gower’s co-efficient for mixed data, principal coordinates analysis, and partitioning analysis (vander Kloet et al. 2003).  They re-circumscribed Vaccinium sect. Aethopus Airy Shaw not only merging V. setipes under V. paucicrenatum but also included other four species as valid and another four species as synonyms under these valid species transferring from Vaccinium sect. Vitis-idaea (Moench) W.D.J. Koch.  These species are V. nummularia Hook.f. & Thomson ex C.B. Clarke (V. chaetothrix Sleumer as a synonym), V. retusum (Griff.) Hook.f. ex C.B. Clarke (V. haitangense Sleumer as a synonym), V. moupinense Franch. (V. dendrocharis Hand.-Mazz. and V. merrillianum Hayata as synonyms), and V. delavayi Franch.

Shaw (1948) erected a new species, V. setipes, from “Assam population of outer Abor Hills, Ripshing” (Arunachal Pradesh in India) of V. paucicrenatum Sleumer based on I.H. Burkill collection (no. 36976, K photo!) which was cited by Sleumer (1941) as V. paucicrenatum in the protologue.  Shaw (1948) distinguished “Assam” population of V. paucicrenatum as V. setipes due to the presence of unique hispid-setose pedicels and axillary fascicled raceme which are not found in V. paucicrenatum Sleumer.  Therefore, Shaw (1948) erected a new species, V. setipes under Vaccinium sect. Aethopus Airy Shaw.

As a result of taxonomic revisionary work on the Indian Ericaceae under “Flora of India Project” of the Botanical Survey of India (1999–2004), as well as other national projects (UGC) on Indian Ericaceae (2009–2011) and a project (2014–16) to supervise national scholar (Rajiv Gandhi Fellow, UGC), extensive field visits were done during these periods at different localities of the eastern Himalaya including a major part of Arunachal Pradesh by the author.

From the visits, specimens from three interesting epiphytic Vaccinium populations from three different districts of Arunachal Pradesh were collected on 24 April 2003 from Lohit (S. Panda 30881, CAL), 25 February 2010 from Kurung Kumey (S.S. Dash 31690, ARUN-Aruncahal Pradesh Herbarium, Botanical Survey of India at Itanagar), and 21 November 2014 from Lower Subansiri (S. Panda, P. Roy & D.S. Mahanty, 55, DGC-Darjeeling Govt College Herbarium).  Number of individual plants were counted at Lohit population (7) and Lower Subansiri population (6).  Based on these exomorphological and leaf anatomical data, specimens of Vaccinium L. are identified as V. paucicrenatum Sleumer.  According to Airy shaw (1948), V. paucicrenatum was not reported from India. But according to vander Kloet et al. (2003), V. paucicrenatum had been reported by Sleumer (1941) based on I. H. Burkill collection (no. 36976, K) from Outer Abor Hills in 1912.

 

Materials and Methods

The present work is the result of an extensive field visit in different districts of Arunachal Pradesh in 2003–2014 as well as herbarium consultations in Indian herbaria (CAL, DD, ASSAM, ARUN).  This work also recorded GPS points (used GARMIN eTrex 10 model) data (latitude-longitude and altitudes) during field visits.  The work was carried out partly in Central National Herbarium (Voucher specimen deposited: S. Panda 30881: Lohit population) and partly in the laboratory of Angiosperm Taxonomy & Ecology, Barasat Govt College (S. Panda 30881: Lohit population-leaf anatomy), Darjeeling Govt. College (Lower Subansiri Population Panda et al. 55: Darjeeling Govt College Herbarium).  Fruiting materials of V. paucicrenatum belonging to S.S. Dash 31690 (ARUN: Arunachal Herbarium, Botanical Survey of India) was consulted in November, 2014 at Arunachal Herbarium by the author. Botanical identity was confirmed with consultation of Type images (BM!; K!) as well as consultation of relevant literature including protologue.  Amplified description of V. paucicrenatum is based on all three field collections (S. Panda 30881, S.S. Dash 31690, & S Panda et al. 55) as well as type images (Kingdon-Ward 13560, BM; Burkill 36976, K).

 

Stomatal slide preparation

Small cubical pieces of leaf blades were excised from the base, middle and apex.  Several existing methods viz., 10% HNO3-boiling for 10 minutes, 5% KOH overnight (12–24 hours) treatment without boiling and with boiling were done.  Pieces were ringed in sterilized water until clear.  After clearing, pieces were dehydrated in an ethanol series followed by staining with 10% safranin and mounted onto a microscope slide in DPX (pieces of basal, middle and apical regions on one slide).  The slide was examined under Olympus (Tokyo: Model no. SAI740) light microscope using 10X and 40X objectives and camera lucida drawings were made with the help of a drawing prism.  The slides (5 for each) are deposited in the Laboratory of Angiosperm Taxonomy, Post Graduate Department of Botany, Barasat Government College (2010) & Darjeeling Govt College (2016).  The descriptive terminology follows Dilcher (1974) and Carpenter (2005).

 

Methodology of leaf clearing for venation study (areoles)

Entire mature leaves were immersed in 2.5% NaOH solution until clear (closed condition).  In the present study, most of the leaves were cleared after eight days of NaOH treatment.  After eight days, these NaOH-treated leaf samples were again immersed in 2.5% NaOH solution for 2–3 days followed by one drop chloral hydrate treatment overnight.  Leaf samples were then washed in distilled water.  After clearing, one good sample (entire leaf) was dehydrated in an ethanol series followed by staining with 1% safranin and mounted onto a microscope slide in DPX (entire leaf in one slide).  The slides are deposited in the laboratory of Angiosperm Taxonomy, PG Department of Botany, Barasat Govt. College (2010) & Darjeeling Govt College (2016).  The descriptive terminology follows Hickey (1973) and Dilcher (1974).

 

Taxonomic treatment and amplified description

 

Vaccinium paucicrenatum Sleumer

(Images 1–5; Figure 1)

in Engl., Bot. Jahrb. Syst. 71(4): 432–433. 1941; Merrill, Brittonia 4(1): 157. 1941; Airy Shaw, Kew Bull. 1948: 246. 1948; vander Kloet et al., Acta Bot. Yunnanica 25(1): 21. 2003; Panda & Sanjappa in Sanjappa & Sashtri, Fasc. Fl. India (Ericaceae) no. 25: 399–400. 2014. Type: Northern Myanmar, Nam Tamai valley, hills east of Putao, 27.7530N & 97.5000E, 1600 m, 09.xii.1937, Kingdon-Ward 13560 (BM, photo!).

Epiphytic trailing profusely branched shrub to 1m high; growing on a fallen Quercus tree with irregularly lobed basal lignotubers which are 5–7 × 4.5–6.5 cm, glabrous, pale brown; each lobe of lignotuber appearing like a potato tuber.  Stem glabrous, lenticellate; old branches beset with sparsely blackish hispid-setose hairs while current season’s branches (young twigs) beset with dense brown hispid-setose hairs (up to 4mm long), terete.  Leaves closely appressed to branches, alternate to sub-opposite, lamina usually ovate-elliptic to elliptic (but Lohit population-S. Panda 30881 showed usual elliptic to rarely ovate-elliptic shape), 10–16 × 6–10 mm (Kurung Kumey-S.S. Dash 31690 and Abor Hill-Burkill 16976) populations showed larger leaves viz., 13–16 × 7–10.5 mm and 12–15 × 7–10 mm respectively, while Lohit population- S. Panda 30881 showed smaller leaves 9–13 × 7–9 mm), obscurely serrate at margin (5–6 obscure teeth on each side), serration found only on upper 3/4th half but basal 1/4th half entire, usually apiculate to rarely acute at apex (Lohit population S. Panda 30881 showed shortly acuminate apex, acumen up to 1mm long), broadly cuneate to subrotundate at base, glabrous on both surfaces, dark green and shiny adaxially while light green abaxially, apical leaves of current season’s greenish with purple-red; venation conspicuously brochidodromous with 2–3 pairs of lateral veins, prominent on both surfaces, thinner veins adaxially but comparatively thicker abaxially (however, variations noticed in different populations, viz., Kurung Kumey population showed veins prominent adaxially and obscure abaxially; Lohit population showed veins prominent abaxially while obscure adaxially; Lower Subansiri population showed veins prominent on both surfaces including some leaves of adaxial surfaces showed obscure veins on the same branch).  Petioles usually 1mm to rarely 1.5mm long; Lower Subansiri population showed petioles usually beset with tuft of brown hispid-setose hairs up to 3mm long, while dry herbarium materials showed glabrous or hair-scars on petioles (may be due to deciduous nature of hairs which fall off in dry materials).  Racemes almost absent or much reduced and flowers solitary, axillary from middle to subterminal parts of current season’s branch.  Flowers pentamerous, c. 10mm long including 2–3 mm long short pedicels which are light green, basally hispid-setose with a tuft of brown hairs and encircled by 6–8 brown-purple bracts.  Bracts persistent in fruits, ovate-deltoid to broadly ovate, acuminate at apex, 2–3 × 1–1.5 mm, glabrous except basal part of dorsal surface puberulous, obscurely serrate at margin.  Calyx purplish-red-white, obconical, persistent in fruits, c. 2.5mm long, glabrous, 5-lobed, basally connate, narrowly deltoid, 1.5–2 × 1 mm, shortly acuminate at apex.  Corolla tubular-urceolate, white with longitudinal purple-red lines along 5-ridges, c. 6mm long (buds c. 4mm long), glabrous except apical lobes inside puberulous, 5-lobed, apical part 4mm in diam., each lobe minute or 0.5mm long, reflexed after anthesis, puberulous inside.  Stamens 10, ecalcarate, c. 5mm long; filaments slender, light green, basally dilated, c. 1.5 mm long, glabrous, filament wall wavy at margin with a prominent median vertical vein seen; anther lobes (thecae) oblong to linear-oblong, brown, c. 1.5mm long, verrucate, appendiculate (c. 0.5mm long at the base of thecae), at the apex of thecae c. 2mm long two linear pale yellow tubules seen.  Pistil c. 8mm long; ovary glabrous, 1 × 1.5 mm, subglobose, light green, 5-locular on axile placentation; style filiform, light green, c. 5mm long, glabrous, obscure several vertical ridges seen, protruded up to 1mm out of mature flower; stigma truncate.  Berries greenish with pinkish tinged apex and 3 × 2.5 mm (immature) to purple-black and 4 × 3.5 mm (mature), encircled with persistent 6–8 purple-brown bracts and five purple-red calyx.  Seeds several, obconical, 1.5 × 1 mm, pale brown, scariosus.  Floral formula: Br., Brl., ⊕ ,, K(5), C(5), A(10), ¯G(5).

Leaf anatomy: Stomata (Image 5G–I): The study of Light Microscopic stomatal architecture (40X, 100X) includes number, form and arrangement of specialized epidermal cells associated with the stomatal guard cells.  Stomata are distributed more or less evenly over the entire abaxial leaf surface in between the veins, but generally not over the finer veins and main veins.  The stomata are uniformly distributed in abaxial surface only, they are widely separated from each other by epidermal cells.

Stomata type: The investigated species shows only one type, amphiparacytic (Dilcher 1974).  Average dimension of stomata is 22.5 × 20 µm.  Average dimension of guard cells: 10.3 × 2.4 µm.  Epidermal cells are variable ranging from polygonal, pentagonal, rectangular to irregular and mostly isodiametric, some are elongated to deltoid.  The epidermal walls in surface view are slightly arched to rarely straight.  The epidermal walls in the adaxial surface are mostly straight.  The maximum length of epidermal cell is 39.5µm and breadth is 22.5µm, while minimum length is 18µm and breadth is 14µm.

Leaf areoles (vein islets) (Image 5 A–F): Quadrangular, pentagonal to rarely triangular in shape.  Larger areole: 974 × 614 µm.  Smaller areole: 374 × 112 µm.  Areoles: 3 (average) per 1mm2.  Vein endings: 24 (average) per 1mm2; veinlets simple unbranched to branched (once).  Branched and unbranched veinlets occur in the same areole.  Vein ends: pointed to bifurcated.

Extended distribution: India: Eastern Himalaya (Arunachal Pradesh: outer Abor Hills-Ripshing 1,676m  (Adi  dominated part of East and West Siang districts)); Lohit District between Tezu & Hayuliang 1,300m 27.972°N & 96.440°E; Lower Subansiri district-between Manipolyang & Pange 2,100m, 27.526°N & 93.899°E; Kurung Kumey district-above Nyapin 1,570m, 27.719°N & 93.375°E; N Myanmar (Burma-Tibet Frontier: Nam Tamai Valley, Hills east of Putao-899–1,600 m, 27.7530N & 97.5000E). vander Kloet et al. (2003) erroneously reported this species from China (SE Tibet) based on the specimen, Kingdon-Ward 9124 (BM, GH). However, Merrill (1941) and Airy Shaw (1948) reported this specimen  from Nam Tamai Valley of N Myanmar.

Habitat: A trailing profusely branched epiphytic shrub up to 1m long growing in the higher branches in the canopy, mostly on Quercus trees at altitudes ranging from 1,295–2,126 m  in Arunachal Himalaya while 899–1,600 m  in the hills of Myanmar (Image 1).

Phenology: Flowering in early November to late January, peaking in late November to late December (but rarely in March in Abor Hill population collected by I.H. Burkill 36976).  Fruiting: early February to late March, peaking in late February.

Specimens examined: 30881 (CAL, veg), India: eastern Himalaya: Arunachal Pradesh: Lohit District, 45km from Hayuliang toward Tezu, near Salangam, 1,300m, 27.972°N & 96.440°E, 24.iv.2003, coll. S. Panda;  55 (DGC, fl.), Lower Subansiri District, 4km from Manipolyang toward Pange, 2,125m, 27.526°N & 93.899°E, 21.xi.2014, coll. S. Panda et al.; 31690 (ARUN, fr), Kurung Kumey District, above Nyapin, 1,570m, 27.719°N & 93.375°E, 25.ii.2010, coll. S.S. Dash.

 

For figure & images - - click here

 

 

References

 

Airy-Shaw, H.K. (1948).  Studies in The Ericales: VIII. A new section of Vaccinium from the Eastern Himalaya. Kew Bulletin 1948: 244–247.

Carpenter, K.J. (2005). Stomatal architecture and evolution in basal angiosperms. American Journal of Botany 92(10): 1595–1615.

Dilcher, D.L. (1974). Approaches to the identification of angiosperm leaf remains. Botanical Review 40(1): 1–53.

Hickey, L.J. (1973). Classification of the architecture of dicotyledonous leaves. American Journal of Botany 60(1): 17–33.

Mabberley, D.J. (2008). Ericaceae: Vaccinium L. Mabberley’s Plant-Book: A Portable Dictionary of Plants, Their Classification and Uses. 3rd Edition. Cambridge University Press, Cambridge, 889pp.

Panda, S. & M. Sanjappa (2014). Vaccinium L, pp. 390–400. In: Sanjappa, S. & A.R.K. Sastry (eds.). Fascicles of Flora of India: Fascicle 25 Ericaceae. Botanical Survey of India, Kolkata.

Merrill, E.D. (1941). The Upper Burma Plants collected by Captain F. Kingdon Ward on the Vernay-Cutting Expedition 1938–39. Brittonia 4(1): 157.

Sleumer, H. (1941). Vaccinioideen-Studien. Botanische Jahrbucher Systematik 74(4): 432–433.

vander Kloet, S.P., T.A. Dickinson & W. Strickland (2003). From Nepal to Formosa, a Much Larger Footprint for Vaccinium sect. Aethopus. Acta Botanica Yunnanica 25 (1): 1–24.