erquint's Favorites

A rotifer from the intertidal benthos of marine estuary Acabonac Harbor at Louse Point, a new sampling site for me. The rotifer measures 125 um. I have tentatively narrowed it down to a Proales species.

The Proalidae constitute a small family of monogonont rotifers, including 4 genera and about 54 valid species. The largest genus, Proales, with some 43 species is a fairly heterogeneous group, which at present cannot be revised thoroughly on basis of the existing knowledge. Most of the earlier descriptions mainly focused on external morphology which is very similar indeed for the different taxa, whereas the descriptions of the highly species specific trophi are mostly inadequate. It has become clear, however, that only a detailed study of the trophi, especially with scanning electron microscopy, will allow for a finer regrouping within Proales and for a better understanding of the evolutionary relationships.

Family Proalidae Out of the 4 genera in the Family, only Proales has representatives in saltwater. Seventeen valid species (out of 43) are known to live in saltwater habitats. Proales commutata, P. germanica, P. halophila, P. litoralis, P. oculata, P. reinhardti, P. similis are strictly marine and often common in marine benthos and psammon, and among periphyton; P. paguri lives on the marine hermit crab Pagurus bernhardus and feeds on the epithelial cells of the gills; P. christinae and P. gonothyraeae are commensal/ectoparasitic epizoics of marine hydroids. Some haloxenous (P. decipiens, P. fallaciosa, P. werneckii) and euryhaline species (P. globulifera, P. minima, P. theodora) have also been reported from saltwaters. The most recent taxonomic revision with keys to the species and general information is De Smet (1996a); for the benthic-periphytic P. litoralis not included in the key, see De Smet (1996b).

Description of Proales litoralis sp. nov. (Rotifera, Monogononta: Proalidae) from the marine littoral. Hydrobiologia 335: 203-208