Polydendrorhynchus amaleshii sp. nov., a New Species With Branched Proboscis (Nemertea: Heteronemertea) From the North-East Coastal Bay of Bengal

A new lineid heteronemertean with a branched proboscis, <i>Polydendrorhynchus amaleshii</i> sp. nov., is described as the second member of the genus <i>Polydendrorhynchus</i> Yin and Zeng, 1986, following <i>Polydendrorhynchus zhanjiangensis</i> (Yin and Zeng, 1984). The description is based on specimens collected from the northeastern coastal Bay of Bengal, including the Subarnarekha Estuary and Frazerganj in the Indian Sundarbans mangrove ecosystem. The new species is distinguished from its congener by having up to 56 terminal branchlets of the proboscis and the absence of rhynchocoel compartments. In a maximum-likelihood phylogenetic analysis based on COI and 16S rRNA genes, <i>P. amaleshii</i> and <i>P. zhanjiangensis</i> formed a well-supported clade. <i>Polydendrorhynchus amaleshii</i> represents the ninth nemertean species recorded from India.