Chaetonotus (Wolterecka) caudalspinosus Visvesvara, 1964

Chatterjee, Tapas & Todaro, M. Antonio, 2021, An annotated checklist of the chaetonotidan Gastrotricha from India, Zootaxa 5027 (3), pp. 332-350 : 339

Chaetonotus (Wolterecka) caudalspinosus Visvesvara, 1964

Records from India. MAHARASTRA: Nagpur— Visvesvara (1964); GENERAL RECORD: Naidu & Rao (2004), Purushothaman (2017).

Habitat (as in Indian records). Freshwater; among algae and aquatic plants.

Distribution. Known only from India.

Remarks. The species was described as a new taxon by Visvesvara (1964) mainly in consideration of the furcal appendages, which appeared to be rather short and plump and ending each with spiny processes instead of the typical adhesive tubes. The author believed the characteristics to be absent among the other species of Chaetonotus described up to then. Clearly, Visvesvara (1964) was unware of Chaetonotus uncinus Voigt 1902 , which shows similar characteristics. The author was also unaware of Remane’s (1936) work, in which the German author established the “ uncinus group” to include the species bearing such an unusual trait. Not withstanding the overlooking, the Indian specimens, in virtue of their combined characteristics, appear to be morphologically different from C. uncinus and thus can be considered as a distinct species i.e., C. caudalspinosus (e.g., Schwank 1990). Surprisingly, C. caudalspinosus was ignored by Kisielewski (1984) while describing Chaetonotus sudeticus , another putative member of the uncinus group; however, the same author considered the Indian species, in his later work dealing with the subgeneric division of the genus Chaetonotus (see Kisielewski 1997).

In the Naidu & Rao (2004) monograph, C. caudalspinosus is reported as belonging to the subgenus Brevipedichaeta . This subgenus was proposed by Schwank, 1990, in replacement of the uncinus -species group of Remane (1936), and subsequently sustained by Kisielewski (1997), who however excluded from it C. brachyurus Balsamo, 1981 . Later, the subgenus Brevipedichaeta was considered invalid by Weiss (2001) and replaced by its senior synonym Wolterecka Mola, 1932 .