Bioacoustics of Teleogryllus (Macroteleogryllus) derelictus

Emended description : Large species. Body covered with dense, short setae. Head. Slightly shorter than pronotum and almost twice wider than long, in dorsal view ( Fig. 4A&B ). Face yellowish to brown in colour and 1.2 times longer than wide in frontal view ( Fig. 5A ). Occiput yellowish in colour with no bands and is slightly bulging in lateral view ( Fig. 4C ). Median ocellus D-shaped and lateral ocelli circular in shape ( Fig. 5A ). Fastigium twice as broad as scape, slightly projecting forward ( Fig. 5A&B ). Eyes large, not greatly protruding. Ocelli large, located in triangle, distance between lateral ocelli is 2.5 times than the distance between median and lateral ocelli. Maxillary palpi with 5 th article, with round yellowish apical margin, slightly widened distally ( Fig. 5B ). Pronotum. Pubescent, uniformly light brown, 1.5 times wider than its length; disk is smoother than in T. mitratu s; its anterior margin straight to slightly concave and posterior margin more or less straight ( Fig. 4A&B ). Legs. T 1 with tympanum on both sides; size of outer tympanum is 3.7 times than inner tympanum, inner tympanum somewhat circular; outer tympanum oval shape. TI with a pair of ventral apical spurs, outer spur smaller than inner; one inner dorsal apical spur. TII with a pair of ventral and dorsal apical spurs, inner spurs smaller. TIII inner sub apical spurs slightly longer than outer; sub-apical spurs on inner margin 5–6 (most often 6 on both sides) and outer 6–7 (most often 7 on both sides). The length of the hind femora, as in the previous species, 3 times greater than the width; hind tibiae with 6 spines on both sides. The dorsal surface of hind legs with 8 spines on the outer side and 6 on the inner side. Basitarsomeres III with 4–5 spines on inner margin and 4–7 spines on outer. FI and FII thin. FIII proximal half almost twice wider than distal half. Color of the legs light brown, monochromatic. The abdomen is pubescent, dark, and uniform in color. Cerci yellowish-brown. Male. FW long, extended beyond abdomen; HW present and much longer than FW ( Fig. 4E ); Mirror 1.5 times wider than long, divided by a curved vein; harp with 4 oblique veins, one of which is weakly expressed, diagonal vein straight ( Fig. 4E ); stridulatory vein bears 146–165 number of teeth (n=2) ( Fig. 9 ); apical field with 5 cell alignments and bearing irregular cells ( Fig. 4E ); lateral field pale, with a brown stripe above; 13 lateral veins present ( Fig. 4C ). Male genitalia . Pseudepiphallus long and acute posteriorly ( Fig. 6A–C ), in lateral view, apical part pointed and bulging in the middle ( Fig. 6C ); in dorsal view, posterior end of pseudepiphallus slightly wider ( Fig. 6A ) compared to T. mitratus (Fig. 10A Jaiswara et al. , 2021 ), the lateral crests much shorter in length ( Fig. 6A ); lateral margin of pseudepiphallus very convex; pseudepiphallic parameres long. Rami strongly convex on its length, without bifurcation posteriorly. Ectophallic fold very long, sclerotized; thin filament-like structure extended way beyond posterior margin of pseudepiphallus. Dorsal cavity long. Female. Similar to male, but slightly larger. Dorsal surface of FW yellowish-brown, with light stripe along fold. FW extending beyond abdomen and HW length much longer than FW; FWs overlapping; FWs with diagonally parallel longitudinal veins on the dorsal side; lateral field of elytra 13–15 branches of Sc. Ovipositor approximately 1.2 times longer than FIII length. Female genitalia. Subgenital plate longer than deep ( Fig. 3D ); copulatory papilla long, with anterior end wider than T. mitratus (see Fig. 11 A&B Jaiswara et al. , 2021 ) Sound analysis. The calling song is short trill type , with 18 to 46 syllables. At 29°C the average syllable duration (SD) is 23±2ms and an average syllable period (SP) is 31±3ms. Average trill duration is 837±371 ms and an average period (CP) is 1080±337 ms. The dominant frequency of the calling song is 3.5 kHz.