Bioacoustics of Smicridea (Smicridea) truncata

Larva. Length 5.7–6.9 mm (n = 9), lateral habitus as in Fig. 1 ; body covered with short, scale-like hairs. Head. Dorsum: yellowish-brown, pattern of dark spots darker on anterior region than posterior; mandibles asymmetrical, left one with 5 internal teeth and one subapicodorsal tooth, brush of hairs in middle region going beyond mesal edge; right mandible with 4 internal teeth, no hairs present in middle region, with 1 tooth ( Fig. 5 ); labrum darkly sclerotized anterolaterally, with long hairs anterolaterally, being more dense anteriorly ( Fig. 4 ), dorsal surface with two setae long and short setae; frontoclypeus, anterior region asymmetrical, left side with shallow crenulations, 2 rounded lobes, right side being larger than left side, anterolateral ends straight, without lateral expansion, median region with transverse dark concave line, anterior region becoming depressed from this point ( Fig. 2 ); venter: transverse stridulatory file ridges decreasing in length anteriorly and posteriorly, with short ridges posteriorly in ventrolateral area of head ( Fig. 3 ); submentum without median cleft; ventral apotome divided, anterior apotome wider than long, triangular in shape, posterior apotome small, sclerotized anteriorly. Thorax. Dorsum: pronotum with longitudinal ecdysial line, several dark spots posterolaterally, highly sclerotized and dark posterolaterally ( Fig. 6 ); meso and metanota entire, with dark spots forming arcuate line in lateral view, dark spot in middle of posterior edge, highly sclerotized and dark anterolaterally ( Figs. 7 and 8 ); cuticle between pronotum-mesonotun and mesonotum-metanotum laterally bearing small tubercles; venter: gills each with elongate stalk, few (4–6) filaments not arising uniformly, absent on prosternum, 1 pair on mesosternum and 2 pairs on metasternum; tibia of forelegs each bearing ventrally at least 8 pinnate hairs; trochantin not forked, with 4 dorsal spines; sclerites posterior to prosternal minute. Abdomen. Gills with elongate stalk, few (4–6) filaments not arising uniformly, 2 pairs on segments I–VI, 1 pair on segment VII; single median sclerite on segment VIII ventrally; segment VIII bearing dorsolaterally 1 pair of tubular structures ( Fig. 1 ), each with apical tuft of setae; anal claw without ventral teeth, brush well developed. Abdominal sternum VIII with circular sclerite bearing numerous setae on posterior margin ( Fig. 9 ). Pupa. Length 5 mm (n=3), dorsal habitus ( Fig. 10 ), labrum with distinct basolateral lobes, each with 5 long hairs, anterior region with 2 long hairs on each side and 5 short hairs on median region ( Fig. 10 ). Mandibles inflated basally, bearing long hairs posterolaterally, each tapering to pointed apex, inner margin with large teeth near base (3 on left mandible, 4 on right) and small serrations beyond; 4 hairs dorsally in middle near base ( Fig. 12 ). Thorax and abdomen with sparse setae, lacking lateral fringe. Hook plates anteriorly on segments II–VIII, posteriorly on segments III–VI ( Fig. 13 ); each posterior plate 3 (3p) wider than longer, bearing 6 large teeth and 10 smaller teeth, distributed in two irregular rows. Apical processes straight, widely separated, each with apical brush of hairs (4 very long), shorter hairs on first third of process, no hair beyond this area until base of process ( Fig. 14 ).