Bioacoustics of Niuailan peterseni

Redescription of male. Body length (without apical horn) 18–23 mm , dorsum very glossy black to brown, venter red-brown, upper surface glabrous, ventral thorax with very dense setae, venter and pygidium more sparsely setose, edges of frons, pronotum and elytra with long red setae. Mentum evenly arcuate in lateral view, setose; labrum concealed; maxillary, palps with apical palpomeres striolate, and non-foveate; mandibles prominent, outer margin convexly curved, without teeth. Clypeus vertical, disc slightly concave, anterior face coarsely punctate, setae sparse and restricted to above mandibles, anterior margin curved with rounded corners, lateral margin slightly concave and ridged in middle with posterior edge curved convexly, posterior margin defined by clypeofrontal ridge that is punctured and coarsely wrinkled. Frons mainly hidden from above by apical pronotal horn that slopes down towards the clypeus, narrowed between the large eyes and a little wider than diameter of one eye, widest at anterior angles, glabrous and smooth except for long, red setae on inner side of eyes and along ocular canthi and patch of similar setae half way between front of eyes and clypeofrontal suture. Pronotum (excluding apical horn) about twice as wide as long, upper surface smooth, very shiny, sloping forwards but without median depression; anterior margin dominated by apical horn, anterior angles obtuse; lateral margins slightly reflexed from obvious groove, strongly concave behind anterior angles, then slightly convex to rounded middle, then weakly concave to very obtuse pos- terior angles; posterior margin almost straight except slightly convex in middle in front of scutellum, with an obvi- ous groove across entire width. Pronotal disc with 3 horns, apical horn horizontally directed forward and reflexed upwards in apical third to well in front of head in larger specimens, apex bidentate, upper surface strongly rugose and lower surface punctate on apical third to half, basal half with lateral ridge curving back to anterior angles of pronotum; slender lateral horns arising from posterior third of pronotum, projecting forwards and curving upwards at about 45°, apices curved inwards to a rounded point and with scattered punctures. Scutellum triangular, surface lightly roughened, basal half with sparse setae. Each elytron slightly longer than combined width at front, sides parallel anteriorly then curving to rounded apices, edges slightly reflexed; basal humeri strong, bounded on inner edge by a stria, apical humeri practically absent, sutural striae linear, well defined and continuing around edge of scutellum, other striae poorly defined, nearly absent beyond basal third, otherwise surface smooth and glossy. Pro- pygidium very densely and heavily setose, without stridulatory surface. Pygidium triangular, coarsely and densely punctured across base to very finely punctured at apex, dense long setae across base, sparse apically, apical ridge glabrous, lateral angles shagreened. Prosternal process short, hidden by setae. Femora strong, especially metafem- ora, with many long setae and rows of punctures; protibia with 3 strong outer teeth all projecting forwards, apical spur long, originating opposite indentation between middle and basal teeth, metatibiae obliquely bicarinate; spurs on mesotibiae and metatibiae reasonably broad and of equal length and straight, all tarsi very thin and simple, tarso- meres 1 and 2 of similar length, tarsomere 1 slightly shorter than tarsomere 5; claws equal. Parameres slim, tapering to apex and with tip slightly curved outwards, lateral edge evenly and slightly concave. Female. Unknown.