Polymerurus nodicaudus (Voigt, 1901)

Chatterjee, Tapas & Todaro, M. Antonio, 2021, An annotated checklist of the chaetonotidan Gastrotricha from India, Zootaxa 5027 (3), pp. 332-350 : 343

Polymerurus nodicaudus (Voigt, 1901)

Records from India. MAHARASTRA: Nagpur— Visvesvara (1963); GENERAL RECORD— Naidu & Rao (2004).

Habitat (as in Indian records). Freshwater; among freshwater aquatic weeds with attached muds in shallow part of tanks.

Distribution. Cosmopolitan.

Remarks. The species was found in India by Visvesvara (1963). According to the author, the specimens agree with data reported in literature for the species except for the lower number of furcal segments (17 vs 22). Mormetric details were not provided for the 10 studied specimens. However, on the basis of the scale bar it is possible to establish some measures of the drawn specimen, which are as follows: total length, 244 μm, pharynx length, 35 μm, and furca length 67 μm. Based on these measurements, the sketched specimen appears much smaller than specimens recorded from other geographic places (Total length 300-500 μm, pharynx length 40-90 μm, furca length 60-150 μm; data from Schwank 1990).

Naidu & Rao (2004) mention much smaller specimens (up to 200 μm in total length) from Nagpur, but it is unclear if these are the same specimens reported by Visvesvara (1963) or new specimens.

Regardless, based on the available information, the presence of P. nodicaudus in India should be considered solely provisional. Future data from fresh material should confirm of disprove the presence of this morphospecies in India. Population genetic studies could challenge the reported cosmopolitan distribution of this taxon (see the preliminary work by Kånneby et al. 2012 and also Magpali et al. 2021).