Odontomesa Pagast, 1947

Liu, Wenbin, Ferrington, Leonard C. & Wang, Xinhua, 2016, First record of Odontomesa Pagast from China, with description of the immature stages of O. ferringtoni Saether (Diptera, Chironomidae, Prodiamesinae), Zootaxa 4132 (1), pp. 135-142 : 136

Odontomesa Pagast, 1947

Type species: Prodiamesa fulva Kieffer, 1919 , by original designation.

Diagnostic characters (following Saether 1983; 1986a; 1986b; Saether & Andersen 2013; Langton 1991): The characters of the anal point (reduced to small, triangular point with microtrichia, but no setae) and gonocoxite (large and rounded), in combination with the shape of volsellae (superior volsella small, with microtrichia; median volsella reduced to a small projection with 1–4 setae; inferior volsella very long, flat and lobe-like, covered with microtrichia and setae) will easily differentiate Odontomesa adults from other genera in the subfamily Prodiamesinae . The very well-developed thoracic horn, evenly broad, digitiform and covered with spinules, and posterlateral extensions of segment VIII combined with fringe on elongated anal lobes and usually 5 (sometimes 3) anal macrosetae will differentiate the pupae from the ones of all the other chironomids. The larval head capsule of the genus is unique in almost all features as follows: SI biarticulate with apical part laterally fringed; chaetae twisted, with lateral fringe in apical half; chaetulae laterales thin and fringed; the conspicuously shaped and heavy mandible; ventromental plate broad and long, and strong setae in beard.

Emended diagnosis. Based on the material examined and references, the generic diagnosis of the pupa and larva of Odontomesa ( Saether 1983; 1986b; Saether & Andersen 2013) must be emended as follows: Pupa. Frontal setae situated on frontal apotome, sometimes apically on small cephalic tubercles ( O. ferringtoni Saether ); segments VIII with posterolateral, triangular extensions, L3 sometimes situated on extension ( O. ferringtoni Saether ). Larva. Medium-sized larva, up to 8.49 mm; seta interna of mandible with 12–40 branches in O. fulva (Kieffer) ; supraanal setae nearly half as long as anal setae in O. fulva (Kieffer) and in O. ferringtoni Saether.