Meksuwan, Phuripong, Pholpunthin, Pornsilp & Segers, Hendrik, 2011, Diversity of sessile rotifers (Gnesiotrocha, Monogononta, Rotifera) in Thale Noi Lake, Thailand, Zootaxa 2997, pp. 1-18 : 5

publication ID 10.5281/zenodo.207999


persistent identifier

treatment provided by


scientific name



Acyclus sp.

( Figs 2 a– 2 View FIGURES 2 A – 2 I c)

Although only a single specimen of this taxon was observed, we believe that it may represent an undescribed species. Morphologically, the animal is characterized by a prominent bifid anterior margin of dorsal corona lobe ( Fig. 2 View FIGURES 2 A – 2 I c) which is reminiscent of Atrochus tentaculatus Wierzejski, 1893 , the sister taxon of Acyclus . The single known species of Acyclus , A. inquietus Leidy, also occurs in Thale Noi Lake but is easily distinguished by a rounded anterior margin of dorsal corona lobe. Moreover, the specimen of Acyclus sp. was observed predating on a colony of Lacinularia flosculosa (Müller) , whereas all of the specimens of Acyclus inquietus we observed were found in association with colonies of Sinantherina socialis (Linnaeus) . Acyclus inquietus feeds on eggs and larvae of S. socialis whereas Acyclus sp. was seen to predate on adult specimens of L. flosculosa ; the Acyclus sp. takes up a Lacinularia in its vestibulum, sucks out its content of its victim and finally releases the remains, an empty trunk and foot.