Letana dentata, Nagar, Rajendra & Swaminathan, R., 2015

Nagar, Rajendra & Swaminathan, R., 2015, Occurrence of a new species of Letana (Orthoptera: Tettigoniidae: Phaneropterinae) in India, Zootaxa 4044 (3), pp. 429-445 : 430-434

Letana dentata sp. nov.

( Fig. 1 ; Plate I & II)

Material examined. (06 Specimens, 3♂ &3♀)

Holotype. India: Meghalaya; Ri-bhoi; Umaran; Umsning 3.vi.2013, Coll. Rajendra Nagar ( RRTC, Ri-bhoi).

Paratypes. 4.vi.2013, Coll. Jhabar Mal (Ri-bhoi, Umiam, NEH); 6.vi.2013, Coll. Jhabar Mal (Ri-bhoi, Umiam, NEH); 6.vi.2013, Coll. R. Swaminathan (Ri-bhoi, Umiam, NEH); 7.vi.2013, Coll. Rajendra Nagar (Ribhoi, Umiam, NEH); 8.vi.2013, Coll. R. Swaminathan (Ri-bhoi, Umiam, NEH).

Description. Male: Length of stridulatory field 3.80 mm, width 1.90 mm, longer than broad; tegmina surpassing hind knees, hind wing 3.00– 3.30 mm longer than tegmina, stridulatory file sub-straight, slightly curved at base on underside of left tegmina with about 120 teeth larger and small teeth that are narrow and densely arranged in the basal third; large and separated from each other in central and apical areas. Ninth abdominal tergite small, projecting broadly at posterior apex, rounded, but faintly concave in baso-middle. Supra-anal plate with lateral margin concave, surface shallowly depressed, apex sub-truncate, apico-lateral angle slightly protruding. Cerci slightly curved, dorsally straight, but in lateral view slightly constricted in middle and slightly widening again towards apex; apex rounded with an acute black tooth on the internal side. Subgenital plate divided to almost base, bent dorsally and proximate thus that its apex is hidden under the projection of the ninth abdominal tergite, apices of lobes with apical part slightly widening, flat apically, pointed anteriorly with apex rounded. Phallus large feeby sclerotised at base, shining black, anteriorly rounded, apical part bulging with eight small teeth on ventral surface, apically widened and with hooked medial parts, posterior part forked, smooth with apex acute.

Female: Ovipositor short sabre-shaped, part of dorsal and ventral margins dentate near apex; supra-anal plate round with groove in middle, cerci slender, apex sub-obtuse; subgenital plate broad with medial incision slightly straight, lateral angles triangular and apex rounded.

Coloration. Yellowish brown with red dots (specimens in hand were alcohol preserved and were faded, probably green when alive), head, occiput yellowish reddish white, genae light brown with some times reddish dots, frons pale and white; antennae black, annulated with white; scapus and flagellum reddish; fastigium vertices reddish brown; pronotum reddish brown, dorsal margin, lateral pale yellow with red dots; meso- and meta-pleuron white except episternum; abdominal first three and four segments reddish brown in dorsal view with small red dots; PLATE I. Letana dentata sp. nov. male 1–13: 1. Male dorsal view; 2. Female lateral view; 3. Antennae; 4. Dorsal view of head with fastigium vertices; 5. Lateral view of pronotum;6. Lateral view of pronotum; 7. Dorsal view of stridulatory file; 8. Mirror on right tegmina; 9. Ventral view of stridulatory file on left tegmina; 10. Left cerci (a) apex view; 11. Dorsal view of ninth tergite; 12. Ventral view of subgenitalia plate; 13. Lateral view of genitalia.

PLATE II. Letana dentata sp. nov. male 1–7: 1. Dorsal view of phallus sclerite; 2. Lateral view of phallus sclerite; female 3– 7: 3. Lateral view of pronotum; 4. Dorsal view of pronotum; 5. Lateral view of ovipositor; 6. Supra anal plate with cerci; 7. Ventral view of subgenital plate. L. pyrifera male 8–15: 8. Dorsal view of stridulatory file; 9. Mirror on right tegmina; 10. Ventral view of stridulatory file on left tegmina; 11. Dorsal view of ninth tergite; 12. Ventral view of subgenitalia plate; 13. Left cerci; 14. Lateral view of genitalia; 15. Phallus sclerite.

tergites pale yellow; tegmina with costal area brown; hind wing transparent, costal area with whitish brown vein, sub-costal and radial vein, field parts brown and posterior reddish dots, tympana transparent with brown in internal; genitalia apex whitish yellow, cerci white, brown apex teeth black; hind knee brown light brown. Stridulatory file area dorsal margin 1\3 white other dark brown, underside brown with teeth larger and small teeth brown all field dark brown, labrum pale, labial and maxillary palpi, cream white, mandible light dark brown. Female color same but ovipositor apex dentate dark brown.

Discussion. The new species morphologically appears similar to L. bulbosa , L. gracillus, L. navasi , L. recticercis , L. infurcata and L. serricauda , but has a completely different shape of the male ninth tergite, supra-anal plate, subgenital plate and cerci. The major difference is in the male phallus sclerite being hardly sclerotised with the posterior part forked, smooth and acute; and, the difference in the size of stridulatory apparatus. In female, which resembles L. rubescens and L. brevicaudata , the shape of ovipositor, supra-anal and sub-genital plates differ.

Etymology. The name of the new species refers to the phallus sclerite details.

Figures

FIGURE 1. Letana denatata sp. nov. Male 1 – 6: 1. Dorsal view of head; 2. Dorsal view of pronotum; 3. Lateral view of pronotum; 4. Dorsal view of ninth tergite with cerci; 5. Ventral view of sub-genital plate; 6. Lateral view of genitalia; female 7 – 8: 7. Supra anal plate; 5. Left tegmen.