Rostellula, Gorochov, 2018

Gorochov, A. V., 2018, Systematics of the American Katydids (Orthoptera: Tettigoniidae). Communication 8, Proceedings of the Zoological Institute of the Russian Academy of Sciences 322 (4), pp. 398-456 : 430

Genus Rostellula gen. nov.

Type species: Rostellula minutissima sp. nov., designated here.

Etymology. This generic name originates from the Latin word “rostellum” (small rostrum, small nose) in connection with a characteristic structure of the upper rostral tubercle.

Diagnosis. Body small or very small. Upper rostral tubercle ( Figs 157, 166 ) clearly projected forwards (before lower rostral tubercle) and somewhat upwards (these tubercles separated from each other by some space, i.e. apex of lower tubercle distinctly not in contact with upper tubercle), with apical part narrow and roundly truncate as well as ventrally convex (slightly thickened in profile), and with dorsal surface having one distinct median (longitudinal) groove and a pair of small but distinct convexities (partly fused with each other) at base of this tubercle (near lateral ocelli); lower rostral tubercle slightly narrower in apical part and somewhat shorter than upper one; anterior surface of head slightly or distinctly oblique in profile ( Figs 156, 165 ). Pronotum moderately long and narrow, with anterior and lateral edges of disc almost straight, with posterior edge of disc roundly truncate, and with lateral lobe having more or less oblique anterior and anteroventral edges as well as round rest of this lobe (however, this lobe also with rather diverse humeral notch; Figs 156 and 165 ). Wings long (hind wings somewhat protruding beyond tegminal apices); tegmina narrow, with almost parallel costal and anal edges ( Figs 159, 168 ), with long RS (this vein single-branched or having rather long general proximal stock and 2–3 branches in distal part), with single-branched or almost single-branched RA, and with stridulatory apparatus typical of Anaulacomerina ( Figs 158, 159, 167, 168 ). Legs also typical of this subtribe but with all femora lacking spines, spinules or denticles (except for hind femur having a pair of small apical denticles), with hind femur more or less narrow in proximal half, and with sparse spinules on ventral surface of fore and middle tibiae as well as more numerous small spines on all four keels of hind tibia. Last tergite clearly longer than other abdominal tergites; this tergite with very short and wide posterior lobe directed backwards and having almost straight (truncate) posterior edge, or almost without such lobe and having posteromedian edge widely and shallowly concave; epiproct moderately small, elongate and rounded at apex; paraprocts smaller (shorter) and also rounded; cerci not very long and more or less simple in shape ( Figs 161–163, 170–172 ); genital plate rather short, with slightly narrowed distal part having not very deep posteromedian notch and a pair of small posterolateral lobules (styles undeveloped; Figs 161, 163, 170, 172 ); genitalia completely membranous and rather compact ( Fig. 164 ).

Included species. Type species and R. santacruzi sp. nov.

Comparison. The new genus differs from the other genera of Anaulacomerina in the characteristic shape of upper rostral tubercle and simple structure of male abdominal apex (last tergite lacks large processes or lobes, epiproct is small and very simple in shape, cerci are moderately short and not strongly specialized, genital plate is also rather short, and genitalia are without sclerotized parts).

Figures

Figs 156–172. Rostellula gen. nov., male: 156–164 – R. santacruzi sp. nov.; 165–172 – R. minutissima sp. nov. Head with pronotum from side (156, 165); rostral region of head from side (157, 166); stridulatory apparatus of right tegmen (158, 167); left tegmen (159, 168); distal part of hind wing (160, 169); abdominal apex from below (161, 170), from above (162, 171), from side and slightly behind (163), and from side (172); genitalia from above (164).