Orestes diabolicus, Joachim Bresseel & Jérôme Constant, 2018

Joachim Bresseel & Jérôme Constant, 2018, The Oriental stick insect genus Orestes Redtenbacher, 1906: Taxonomical notes and six new species from Vietnam (Phasmida: Heteropterygidae: Dataminae), Belgian Journal of Entomology 58, pp. 1-62 : 25-27

Orestes diabolicus sp. nov.

urn:lsid:zoobank.org:act:B680C282-DF2B-4593-8FEC-2FBA75D2F34B

Figs 5 , 13–14

ETYMOLOGY. The species epithet diabolicus (adj., Latin) means “characteristic of the devil” and refers to the strongly spinose aspect of the species.

TYPE MATERIAL. VIETNAM. Holotype ♂: Lam Dong prov. Bidoup Nui Ba N.P., 12°26’N 108°30’E, 21-25.VII.2014, night coll. Leg. J. Constant & J. Bresseel, GTI project, I.G.: 32.779 ( RBINS).

Paratypes (2 ♂♂): same data as holotype (1 ♂: RBINS; 1 ♂: VNMN).

DIAGNOSIS. Easy to recognise species. Males with strong supra-coxal spines on mesopleura, strong spines on pro-, mesonotum and median segment (Fig. 13 D, I). The reddish brown colouration, relatively longer legs and body armature (Fig. 13 A) also distinguish this species from the closely related O. botot sp. nov. Females are unknown.

DESCRIPTION.

MALE (Fig. 13).

Measurements: see table 3.

Head: supra-antennals distinct, conical but blunt and slightly pointed outwards. Supraoccipitals about as large as supra-antennals, blunt and pointing dorsally. Vertex elongated and raised; supra-orbitals positioned at base of crest, distinctly elongated, with apices projecting over sides pronotum, slightly incurving and acute apically. Anterior coronals elongated and spinose near apex of crest. Central coronal small but acute. Posterior and lateral coronals present as small granules. Behind eye, a distinct carina reaching posterior edge of crest. Eyes relatively small, circular and strongly projecting hemispherically. Antennae shorter than legs with 23 segments (n = 3); scapus strongly flattened dorsoventrally with a posterolateral spine and a smaller one mediolaterally; pedicellus cylindrical, slightly narrowing towards the posterior. First antennomere longer than following two ones combined. Antennomeres gradually getting longer till segment XII which is about as long as scapus. Antennal segment XIII shorter, with minute blunt spine mediolaterally; following segments shiny and distinctly shorter. Apical antennomere elongated, slightly longer than the two preceding ones combined and with apex acute.

Thorax: anterior and posterior margins of pronotum more or less the same width, lateral margins concave; anterior margin incurved with a small expansion laterally. Prozona with distinct median line and elevation centrally armed with four distinct raised tubercles. Metazona with a pair of distinct spinose inter-posterior pronotals. Mesonotum with anterior margin thickened and concave; lateral margins smooth with posterior margin slightly wider than anterior one; posteromedially, an inverted V-shaped crest with two distinct spines or tubercles; anterior margin concave. Mesopleura widened above coxae; widened portion notched medially with a spine anteriorly. Metanotum rugose with anterior margin convex, slightly narrowing towards the posterior; suture with median segment indistinct. Metapleura Fig. 13. Orestes diabolicus sp. nov., holotype ♂. A, habitus, dorsal view. B, habitus, lateral view C, habitus, ventral view. D, head and thorax, dorsal view. E, terminalia, dorsal view. F, terminalia anterodorsal view. G, terminalia, lateral view. H, terminalia, ventral view. I, head and thorax, lateral view.

widened above coxae and with strong, elongated supra-coxal spine; anteriorly and posteriorly of supra-coxal two minute lateral spines. Prosternum with sensory areas almost circular. Sensory area on profurcasternum small and circular. Mesosternum with four spinose tubercles and metasternum with two spinose tubercles.

Legs: femora with carinae indistinct and posteromedially with a slightly elongated dorsal spine. Profemora slightly shorter than pro- and mesonotum combined, indistinctly curved basally. Mesofemora about as long as mesonotum. Metafemora about as long as profemora. Tibiae with carinae indistinct, slightly longer than corresponding femora and unarmed. Tarsomeres I–III about the same length with a posteromedian rounded hump dorsally. Euplantulae more or less circular and distinctly paler in colour. Claws very small.

Abdomen: median segment with two strong, elongated spines projecting posterodorsally; posterior margin straight. Abdominal segments relatively smooth. Tergum II distinctly transverse and slightly wider anteriorly; terga III–IV with a small bituberculate hump posteromedially and terga V–VIII with a bispinose hump posteromedially; tergum VII slightly shorter than preceding one; tergum VIII about as long as VII, widening towards the posterior and distinctly concave posteriorly; IX shorter than VIII and distinctly transverse with posteromedian and posterolateral humps. Anal segment dorsoventrally flattened and with a distinct tooth mediolaterally; apex notched, with posterolateral angles rounded. Poculum triangular from lateral view and strongly granulose; posterior rim dorsoventrally flattened and deeply notched posteromedially, projecting over base vomer but not reaching base of apical spine. Cerci short, strongly flattened and setose, not reaching apex of tergum X and with apices broadly rounded to almost straight. Vomer well developed, semicircular basally till base of posteromedial spine; posteromedial spine black in the posterior portion with acute apex; apex curved not ending medially but slightly to the right.

DISTRIBUTION. Vietnam, Lam Dong province ( Fig. 5 ).

Figures

Fig.5. Orestes. spp., distribution map.