Prosternum with anterior lobe short, directed
ventrad; prosternal process with ventral surface directed dorsad at 45[degrees], not carinate laterally.
Tail conoid curved
ventrad with rounded tip, 1.5-1.7 anal body diameter long.
Spiracle on A1 located
ventrad and cephalad, whereas that of A2 is aligned with the remaining spiracles and located at center of segment in lateral view.
Subgenital plate semicircular, basal margin nearly straight, posterior margin arched projected, center of which with 1 long conical processes, apex subacute, curved
ventrad. Styli conical, inserted on both sides of posterior margin of subgenital plate.
Face (Figs 1, 3) with dorsal three quarters generally brown, parallel-sided, with lateral and especially ventral margins yellowish, generally flat, ventral margin of this portion distinctly convex; ventral and ventrolateral portions shiny to subshiny, subshiny portions greyish microtomentose; gena with thin area immediately
ventrad of eye whitish to silvery white, microtomentose; postoccipital thin area immediately posterior to posterior margin silvery white, microtomentose.
At the sub-generic level, the speciose subgenus Hippichthys is characterized by the lateral trunk ridge being deflected
ventrad at the anal ring while Parasyngnathus has no lateral trunk ridge deflection at the anal ring (Dawson 1985).
12, 25, 31) and a serrated keel at the base of a filiform embolus, curved prolaterally dorsad, running a semicircle behind tegulum, appearing retrolaterally and pointing
ventrad in the male palp (Figs.
Heteropterodea is supported by the following synapomorphies: four antennal segments, body with a flattened dorsal area to receive the wings (Hennig 1969, 1981), anal veins of forewing fused forming a Y-shaped vein (Wootton 1965), last antennal segments larger than proximal ones, abdominal tergites flat with sharp connexivum, abdominal spiracles directed
ventrad, anal cone forming a single, exposed element (Schlee 1969d), and wing coupling mechanism of heteropterous type (China 1962).
El grupo incluye siete especies pequenas que presentan el diverticulo ventral de los genitales masculinos recurvado
ventrad: Belostoma lariversi De Carlo, 1969; B.
Ventral lip of squamosotympanic fenestra--smooth, without a beaded rim or a depression
ventrad (1); raised as a beaded rim, with distinct depression below it (2).