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

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Acyclus  sp.

( Figs 2 a – 2View 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. 2View 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.