Poecilobdella lakshmikantai, A New Leech from Arunachal Pradesh, India
C. K. Mandal *
Zoological Survey of India (Ministry of Environment, Forest and Climate change, Government of India), FPS Building, Indian Museum Campus, 27 JL Nehru Road, Kolkata-700016, India.
M. Bose
Zoological Survey of India (Ministry of Environment, Forest and Climate change, Government of India), FPS Building, Indian Museum Campus, 27 JL Nehru Road, Kolkata-700016, India.
P. Sharma
Zoological Survey of India (Ministry of Environment, Forest and Climate change, Government of India), FPS Building, Indian Museum Campus, 27 JL Nehru Road, Kolkata-700016, India.
S. Mridha
Zoological Survey of India (Ministry of Environment, Forest and Climate change, Government of India), FPS Building, Indian Museum Campus, 27 JL Nehru Road, Kolkata-700016, India.
R. Sikdar
Zoological Survey of India (Ministry of Environment, Forest and Climate change, Government of India), FPS Building, Indian Museum Campus, 27 JL Nehru Road, Kolkata-700016, India.
M. N. Hasan
Zoological Survey of India (Ministry of Environment, Forest and Climate change, Government of India), FPS Building, Indian Museum Campus, 27 JL Nehru Road, Kolkata-700016, India.
S. Ghosh
School of Biological Science, NISER, Bhubaneswar-752050, India.
*Author to whom correspondence should be addressed.
Abstract
Leeches of the class Hirudinea include diverse aquatic and terrestrial forms, and the Indian fauna continues to receive taxonomic additions from under-documented regions. This study describes Poecilobdella lakshmikantai sp. nov. from Dirang, West Kameng District, Arunachal Pradesh, India, based on a specimen collected from a freshwater habitat at 1500 m altitude and deposited in the General Non-Chordata collection of the Zoological Survey of India, Kolkata. The holotype was examined using external and internal morphological characters. The species is assigned to Poecilobdella and diagnosed by a combination of characters, including a dorsoventrally flattened body measuring 35 mm in length and 8 mm in width, 110 annuli, five pairs of eyes, seven black dorsal stripes with dot-like patterning, and a circular posterior sucker with 42 rays. The male gonopore is positioned between annuli 31 and 32, while the female gonopore lies on segment 38, with six annuli separating the gonopores. Internally, the species has well-developed toothed jaws, numerous salivary papillae, elongated crop caeca, an enlarged last pair of caeca, a short-stalked vaginal canal, and a long tubular epididymis. These features distinguish it from known congeners. The record increases the documented leech fauna of Arunachal Pradesh to seven species and supports the taxonomic importance of continued morphological surveys in northeastern India.
Keywords: Hirudinidae, Poecilobdella lakshmikantai, Poecilobdella, new species, leech taxonomy, Hirudinea, Arunachal Pradesh, West Kameng, freshwater habitat, morphological diagnosis, annuli, gonopores