Akemetopon, Weglarz, Kathryn M. & Bartlett, Charles R., 2011

Weglarz, Kathryn M. & Bartlett, Charles R., 2011, Akemetopon, a new genus containing three new species of planthoppers (Hemiptera: Fulgoroidea: Delphacidae), Zootaxa 3007, pp. 50-60 : 52

Akemetopon gen. n.

Type species: Akemetopon inornatum sp. n.

Description. Color dark testaceus, legs and usually head paler; often with pale band on trailing margin of brachypterous forewings. Head narrower than pronotum. Vertex as wide as long, or slightly wider; carinae distinct, median carina weaker; sublateral carinae meeting at fastigium. In lateral view, head pointed ( A. inornatum , A. politum ) or rounded ( A. ainigma ). Frons with lateral margins slightly bowed laterad, widest near base of compound eyes; median carina distinct ( A. inornatum ) or weak ( A. politum , A. ainigma ), forked at fastigium. Antennae short, terete, first antennal segment wider than long, second over twice length of first. Pronotal carinae obscure, reaching ( A. politum ) or not reaching ( A. inornatum , A. ainigma ) posterior margin. Mesonotal carinae weak or obsolete.

Male pygofer broad in lateral view, longer ventrally than dorsally; in caudal view opening round, about as tall as wide; margins rounded (not keeled), ventral margin of opening with caudally projected tooth. Diaphragm welldeveloped, dorsal margin weakly concave leaving large oval-elliptic opening between diaphragm and segment 10; armature U-shaped, with aedeagus resting between thickened, deeply sclerotized ridges. Aedeagus curved ventrad, roughly parallel sided, narrowing in apical fourth to acute apex; with lateral serrations in rows; gonopore subapical and dorsal. Suspensorium evident, base between aedeagus and segment 10 short; arms enclosing aedeagus. Parameres flattened, forceps-like; basal angle weak, widest in apical half, distally narrowing to dorsomedially directed avicephaliform apices. Segment 10 short and wide, bearing small, short hooked processes on caudal margin; segment 11 shorter than segment 10.

Remarks. Akemetopon is an unusual genus. The sharp fastigium of A. inornatum and A. politum is unlike any other North American delphacine planthopper, and the bowed lateral margins of the frons is unusual among North American Delphacini . Despite substantive differences in the head, the genitalia are remarkably similar among species. Superficially it most resembles Pissonotus , but Pissonotus has a rounded fastigium, a pair of median processes on the ventral margin of the pygofer, and the median carina of the frons is forked below the fastigium ( Bartlett and Deitz 2000). The midventral projection of the pygofer opening is an unusual feature among North American Delphacini . It is shared by Kosswigianella (sensu Hamilton 2002, Hamilton and Kwon 2010; viz. Acanthodelphax - K. analis (Crawford) and K. wasatchi Hamilton ; but not K. lutulenta (Van Duzee)) , which differs from Akemetopon in color (stramineous brown with darker abdomen in males), range (northern plus Appalachians), shape of the parameres (diverging), aedeagus (lacking rows of teeth or bearing pair of large terminal processes) and genital diaphragm form. A midventral pygofer projection is also shared with Achorotile , which has similar color but bears sensory pits on the adult and the median carina on the face is paired. Some members of the genera Megamelus Fieber (see Beamer 1955) and Bakerella Crawford (see Beamer 1945, 1950) have a midventral processes on some species, but these genera are quite unlike Akemetopon . A midventral process is also seen in the tropical Old World genus Tarophagus Zimmerman (see Asche and Wilson 1989), but except for this and color, Tarophagus bears few similarities to Akemetopon .

All observed specimens are brachypterous. The only long series was of Akemetopon politum collected by vacuum sampling the grass Muhlenbergia ; the remaining specimens were singletons, or few in number, collected by sweeping or without collecting method provided.

Etymology. The genus name, Akemetopon , is formed by combining a truncation of the feminine Greek word akoke, meaning “a point, sharp edge”, and metopon, the Greek noun for forehead, in reference to the angled fastigium of the type species (remarked on independently by several workers on specimen labels). The name is neuter in gender.