Bioacoustics of Agathomerus

Redescription. Head . Constricted behind eyes; frontal surface along eye margins with ocellate punctures (Figs 1 F , 2 I ); frons variable, impunctate, glabrous. Interocular space usually transverse. Antennae variable in length and shape, usually reaching anterior edge of elytra (Fig. 1 A ), with 11 antennomeres; scapes subconical; antennomeres II globose; III shorter than scape; V – X articulated laterally; XI usually ovoid; scape and II – IV with scattered setae; setae on V – XI short and dense. Eyes prominent and notched (Figs 1 F , 2 I ). Frontoclypeal groove conspicuous. Clypeus trapezoidal, punctate; surface of disc with erect pubescence, posterior region with a transverse, translucent band; labrum oblong, surface of disc sparsely pubescent, edge densely so. Mandibles triangular, not toothed; external side with groove, punctate, and with procumbent setae. Maxillary palps with 4 palpomeres, I subcylindrical, II clavate, III shorter than II and IV, IV subconical or bullet-shaped. Ligula bilobed. Labial palps with 3 palpomeres, I subcylindrical and very short, II clavate and longer than III, III fusiform and longer than I. Mentum bilobed. Gula trapezoidal, punctate. Thorax . Pronotum trapezoidal (Fig. 1 H ) or bell-shaped (Figs 3 G , 4 F , 5 F ), wider than long; base wider than the anterior margin, with anterolateral projections; surface convex, with a groove (either continuous or discontinuous) on the anterior part; posterior part wider than anterior, usually with posterolateral punctures and wide posterolateral projections; posterior edge beaded, as wide as base of elytra. Procoxal cavities closed, procoxae contiguous, conical, protruding; mesocoxae ovate, below level of mesothorax; metacoxae subquadrate, metaxoxal space narrow. Mesoscutum (Fig. 1 G ) with stridulatory files; apical region rounded or slightly emarginate. Scutellum subtriangular (Fig. 1 G ). Elytra with external edges parallel (Fig. 1 A ); surface slightly convex dorsally, punctate; humeri rounded, projecting anterolaterally. Mesanepisternum flat; meso- and metaventral processes not joined (Fig. 1 E ). Metaepisternum with anterior part concave (Fig. 1 D ). Leg pairs progressively longer posteriorly; pro- and mesofemur elongate; metafemur robust, elongate, male with or without ventral projections; metatrochanters truncate; tibiae with a row of denticles dorsally; apophysis long and rounded, apex with 2 spurs; pro- and mesotarsomeres I – III subconical (Fig. 1 L ); metatarsomeres I – III subcylindrical (Fig. 1 M ); on each leg tarsomeres IV reduced in size; tarsomeres V curved, dorsal edge mucronate, ventral edge emarginate, metatarsomere V longer than I – III combined; claws bifid; empodia long, with more than three setae (Fig. 1 K ). Abdomen . Last spiracle smaller than others (Fig. 1 J ); pygidium subtriangular (Fig. 1 J ), apically sparsely punctate and sparsely pubescent; sternite I with anterior edge beaded, abdominal process projected anteriorly between metacoxae; in females, last abdominal ventrite concave apically and, on internal surface, short projection into abdominal cavity. Male genitalia . Aedeagus: dorsal portion of median lobe membranous; struts and lateral margins of median lobe sclerotized (Fig. 1 N ); struts articulated with edge of aedeagus. Parameres long, fused (Fig. 1 O ); tegmen ring lanceolate; roof short (Fig. 1 O ). Female genitalia . Spermatheca complex (Fig. 1 P ); proximal part of spermathecal capsule boomerang-shaped, apex with velum; terminal portion of spermathecal capsule elongate. Sternite VIII bifurcate, apex and base trilobate. Spiculum gastrale straight.