Trachythorax illaesa ( Redtenbacher, 1908 ), 1893

Bresseel, Joachim & Constant, Jérôme, 1893, Review of the Oriental stick insect genus Trachythorax Redtenbacher, 1908 with two new species from Vietnam and comments on egg parasitism and morphological counteradaptations (Phasmida, Lonchodidae, Necrosciinae), Belgian Journal of Entomology 120, pp. 1-56 : 37

Trachythorax illaesa ( Redtenbacher, 1908) stat. rev. comb. nov.

( Figs 25–26)

Necroscia illaesa REDTENBACHER, 1908: 564 [described].

Trachythorax maculicollis – BROCK & DELFOSSE, 2005: 52 [Pantel collection, synonymy]. — OTTE & BROCK, 2005: 336 [catalogued]. — SEOW-CHOEN, 2017: 88 [as synonym of maculicollis ]. — DELFOSSE et al., 2019: 205 [catalogued].

MATERIAL EXAMINED. TYPE MATERIAL. (examined from photographs – Fig. 25 A) INDIA: HT ♂: Shenbagan., VIII.00, N° 3 P. Decoly, MNHN-EO-PHAS800 ( MNHN) .

PHOTOGRAPHIC RECORDS. INDIA: 1 ♂ ( Fig. 25 B): Karnataka State, Mangalore , IX.2018, Jitesh Pai; mating pair ( Fig. 25 E): Karnataka State, Puttur, X.2018, Abhijith A.P.C.; mating pair ( Fig. 25 F) and eggs: Karnataka State, Agumbe, X.2020, Vishwanath Gowda; eggs: Maharashtra state, Mumbai, Nagla trail, 2018, Prajwal Ullal; mating pair and eggs ( Figs 25 D, 26): Maharashtra State, Amboli, 2016 & 2020, Varad B. Giri .

SRI LANKA: mating pair ( Fig. 25 C): Matale, Laggala-Pallegama, 13.IV.2018, iNaturalist user Pieterprins https://www.inaturalist.org/observations/37204645.

COMMENTS. Necroscia illaesa was described based on a single male by REDTENBACHER (1908). BROCK & DELFOSSE (2005) synonymised the species under Trachythorax maculicollis . The holotype male ( Fig. 25 A) differs considerably from the male of T. maculicollis . It lacks the conspicuous pattern on the pro- and mesonotum (by which it also differs from T. yunnanensis ), has a yellow membrane between the head and pronotum and has a conspicuous mediolongitudinal black line on the mesonotum. Thus, it is hereby reinstated as a valid species with the new combination Trachythorax illaesa stat. rev. comb. nov. The species was previously only known from male specimens, but photographic records of mating pairs and eggs have revealed the female and the egg deposition method ( Figs 25 C–F, 26 A).

SUPPLEMENTARY DESCRIPTIONS

FEMALE

Females much resemble males and have a light brown ground colour. The head has a pair of small black spots between the eyes followed by a short mediolongitudinal line; sides of head with black postocular stripe. Pronotum with anterior margin yellow and with a black spot anteromedially; prozona with a pair of black elongate stripes submedially: metazona as prozona: posterior margin with black spot medially. Mesonotum with distinct black mediolongitudinal line not reaching the posterior margin; anterior half with a pair of elongate black markings submedially; strong anteroapical carina parallel to posterior margin followed by a distinct red transverse crescent. Wings brown with dark and lighter mottling, almost reaching the apex of the abdomen in females. The legs are banded light and dark brown, bands less distinct in males.

EGGS ( Figs 26 B–D, 32 C–E).

The eggs of T. illaesa are deposited in groups with the specialised structures of the opercular collar folded against the capsule ( Fig. 26 A–B); they fold open shortly after egg laying to form an almost completely sealed egg-case ( Fig. 26 C–D). Egg capsule ovoid, with polar area glued to other eggs or to a surface. Opercular collar with two large lateral trapezoidal flaps and two small triangular lateroventral flaps. Lateral margins of flaps paler and distinctly toothed. Operculum more or less oval with rounded tubercle subcentrally ( Fig. 26 C–D).

DISTRIBUTION. Southeast India (Karnataka and Maharashtra states), Sri Lanka.