Bioacoustics of Protrellius neesoon

Description. Male holotype . General appearance typical of this genus ( Fig. 1 ). Head with frontal rostrum between antennal cavities approximately as wide as scape. Pronotum moderately transverse (1.3 times wider than long), weakly widening posteriorly ( Fig. 1 ). Fore tibiae with rather large, oval tympana on both side; inner tympanum slightly larger than outer one and hardly immersed ( Fig. 7 ); hind tibiae with 4 pairs of long movable dorsal spines (length of longest inner distal spine 2.6 mm ), not very numerous small immovable spinules between them, and 6 long spurs (=apical spines) (length of longest inner dorsal spur 2.3 mm ). Tegmina reaching distal third of hind femora, with 7 oblique veins (2 proximal veins small) in dorsal field; mirror with 2 dividing veins gently converging medially ( Fig. 2 ); lateral tegminal field with 18 branches of Sc and 9 crossveins between R and M ( Fig. 2 ); stridulatory vein of right tegmen short and sinuous as shown in Fig. 3 , and with 19 stridulatory teeth; hind wings distinctly exposed behind tegmina. Anal (=supra-anal) plate of abdomen simple but with median groove, lateral ridge, and apex truncate; subgenital plate rectangular (longer than wide), with apical part truncate and with median groove, as well as with shallow depression on distal half (as in Fig. 8 ). Genitalia ( Figs 4–6 , 17, 18 ): each posterolateral part of epiphallus with rather short ventral spine, long lateral process directed backwards and having narrowly rounded apex, two dorsal lobules (one directed backwards and slightly bilobate at apex, and one directed partly medially and with rounded apex), and medial ribbon almost reaching small median sclerite of epiphallus; last sclerite with rather wide lateral apodemes and small posteromedian spine; ectoparameres small and with rather thin posterior part; endoparameres with posterolateral arms fused with ectoparameres, wide (long) median bridge, and rather short anterior apodemes; guiding rod rather small, with oval plate-like proximal part and with spine-like distal part situated just under posteromedian spine of median epiphallic sclerite; mold of spermatophore attachment plate not wide, but its apodeme long and directed backwards ( Fig. 4 ). Colouration. Brown with following marks: head with dark patterns on vertex, with median and lateral ocelli white, and with mouthparts light brown; fore and middle femora light brown with 2 brown bands (one near middle, and one near knee); fore and middle tibiae with 2 whitish bands (one just below tympanum, and one near apex); hind tibiae with numerous light brown bands (some of which situated between spurs); tegminal lateral field with membranes between R and M light yellowish brown, and with membranes between Sc branches transparent; abdomen with cerci light brown. Variations. Right tegmina of paratypes with 6–7 oblique veins (2 proximal veins small) in dorsal field; lateral tegminal field with 18–20 branches of Sc and 8–9 crossveins between R and M. Female. Unknown. Measurements. See Table 1 .