Orestes krijnsi, 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 : 38-43

Orestes krijnsi sp. nov.

urn:lsid:zoobank.org:act:69C8EAFB-558E-498B-ADCB-764B2499B5C8

Figs 5 , 21–22 , 23 A–C , 24

ETYMOLOGY. The species is named after Mr Rob Krijns (Netherlands) in acknowledgement for breeding several stick insect species that we brought back from Southeast Asia.

TYPE MATERIAL. VIETNAM. Holotype ♂: Vietnam, Ninh Thuan prov., Nui Chua N. P. , 11°42’N 109°09’E, 3-9.VII.2014, night coll. Leg. J. Constant & J. Bresseel, GTI project I.G.: 32.779 ( RBINS).

Paratypes (3 ♂♂, 4 ♀♀, eggs): 3 ♂♂, 3 ♀♀, eggs: same data as HT, ex breeding R. Krijns, 2017 (2 ♂♂, 2 ♀♀, eggs: RBINS; 1 ♂, 1 ♀: VNMN); 1 ♀: same data as HT, ex breeding D. Dittmar 2017 (RBINS).

DIAGNOSIS. Males have the posterior margin of metanotum distinctly raised ( Fig. 21 I ). Head with anterior coronals spinose, not laterally compressed ( Fig. 21 I ).

Females with cephalic armature except central coronal present as granules ( Fig. 22 I ), tergum IV distinctly widening towards the posterior ( Fig. 22 A ). Metatibiae unarmed. Posteromedial crest on tergum IX distinctly elongated and strongly tectiform ( Fig. 22 E–F ).

DESCRIPTION.

MALE ( Fig. 21 ).

Measurements: see table 6.

Head: supra-antennals conically spinose and slightly pointed outwards followed by two spinose supra-occipitals. Vertex with conically spinose anterior coronals. Supra-orbitals spinose. Posterior and lateral coronals present as small, conical tubercles forming a corona with the elongated apex of the postocular carina. Eyes relatively small, circular and strongly projecting hemispherically. Antennae shorter than legs with 23 segments (n = 1); scapus strongly flattened dorsoventrally and laterally carinate, with a spine laterally and posterolaterally; pedicellus dorsoventrally flattened slightly tapering towards the posterior. First antennomere distinctly longer than pedicellus. Antennomeres gradually getting longer till segment XII. Antennal segment XIII the longest, with minute hump laterally; following segments shiny and distinctly shorter. Apical antennomere elongated.

Thorax: pronotum trapezoidal, slightly wider posteriorly, almost quadrate and tuberculose; anterior margin incurved, prozona slightly elevated centrally with four granules, metazona with four granules; posterior margin rounded. Mesonotum with anterior margin slightly elevated with a pair of minute granules; subcentrally, a pair of minute granules; posterior margin distinctly raised with anterolateral portions tuberculose, posteromedially conically raised, compound and sulcate centrally. Mesopleura widened above coxae; widened portion rounded and slightly crenulated laterally. Metanotum more or less parallel-sided, with posterior margin distinctly raised, posterolaterally with a single tubercle and posteromedially with a pair of raised tubercles. Metapleura widened above coxae with a single blunt spine and notched posterolaterally. Prosternum with sensory areas elongate oval. Sensory area on profurcasternum small and subcircular. Ventral surface of body rugose.

Legs: profemora unarmed, curved basally with anterodorsal carinae slightly more distinct; posterior margin with triangular tubercle; about as long as metanotum. Mesofemora unarmed with carinae indistinct; only slightly shorter than profemora, about as long as metanotum and median segment combined. Metafemora about as long as profemora, shaped like mesofemora. Protibiae unarmed, slightly shorter than corresponding femora. Meso- and metatibiae with carinae indistinct, slightly shorter than corresponding femora and unarmed. Tarsomeres I–III about the same length with a posteromedian rounded hump dorsally. Claws very small.

Abdomen: median segment rugose, strongly transverse and slightly raised posteriorly. Abdominal terga rugose; terga II–V about the same length; tergum VI slightly shorter; tergum II almost quadrate, slightly narrowing towards the posterior; Terga III–VII more or less parallel-sided, unarmed or sometimes armed with two minute granules posteromedially, granules more distinct towards the posterior; tergum VII about as wide as long; tergum VIII wider than VII, trapezoidal and widening towards the posterior, with posterior margin concave; IX about as long as VIII, with posterior margin with distinct posteromedial raised carina and posterolateral margin with a tubercle. Anal segment dorsoventrally flattened with a lateral spine in the anterior half, and notched posteromedially. Posterolateral angles broadly rounded. Poculum more or less rounded and strongly granulose; posterior rim dorsoventrally flattened, thickened and broadly rounded posteriorly. Poculum projecting over base of vomer, reaching base of apical spine. Cerci short, strongly flattened and setose, not reaching apex of tergum X, with apices broadly rounded to almost straight. Vomer well developed, semicircular basally till base of posteromedial spine; posteromedial spine broad, strongly upcurved, with apex black.

FEMALE ( Fig. 22 ).

Measurements: see table 6.

Head: complete armature except central coronal present as granules, supra-antennals slightly larger and conical. Vertex not elongated or raised but slightly rounded. Between lateral coronal and supra-orbital, two equally sized granules. Behind eye a distinct carina reaching posterior edge of crest, resulting in an elongated granule. Eyes relatively small, circular and strongly projecting hemispherically. Antennae slightly shorter than legs with 25 segments (n = 4); scapus strongly flattened dorsoventrally, laterally carinate and with a central and subapical, blunt spine on the outer lateral carina; pedicellus slightly flattened dorsoventrally, narrowing towards the posterior. First antennomere longer than the following two antennomeres combined; antennal segment IV to XV gradually becoming longer. Segment XV with a minute spine anterolaterally, following segments shorter except for apical antennomere which is elongated, club-shaped and distinctly longer.

Thorax: pronotum trapezoidal, widening towards the posterior; anterior margin strongly convex. Prozona with elevation centrally with four raised granules. Metazona with two to six granules slightly convex, posterolaterally with a small granule. Mesonotum rugose with anterior margin thickened, strongly incurved and with two granules anteromedially; lateral margins with few evenly spaced granules; posterior margin wider than anterior margin; subcentrally with a raised pair of granules. Posterolateral and posterior margins granulose and slightly raised. Posterior margin concave. Mesopleura slightly widened above coxae; widened portion distinctly notched medially and with a granule anteriorly. Metanotum more or less parallel-sided, posterolateral and posterior margin granulose and indistincly raised. Posteromedially with a pair of granules Metapleura widened above coxae, anterior portion with few small tubercles, posterolatelly notched. Prosternum with sensory areas elongate oval, not reaching lateral margins. Sensory area on profurcasternum small and more or less circular. Meso- and metasternum relatively smooth with few granules.

Legs: femora with carinae relatively indistinct except for anterodorsal carina of profemora; apex with small granule. Profemora rugose slightly shorter than mesonotum and curved basally. Mesofemora slightly shorter than profemora, dorsally with some small granules. Metafemora about as long as profemora with three evenly spaced raised granules dorsally, central one being most prominent. Tibiae with carinae indistinct and unarmed, pro- and metatibiae about as long as corresponding femora, mesotibiae slightly shorter than corresponding femora. Tarsomeres I–III about the same length with a square posteromedian hump dorsally, IV distinctly shorter. Claws very small.

Abdomen: median segment rugose and strongly transverse and with posterior margin more or less straight. Abdominal terga rugose; terga II–IV distinctly but gradually widening towards the posterior and with lateral margins oblique; tergum IV with a posterolateral spinose tubercle, posteromedially with a twin-crescent-shaped granulose crest; tergum V slightly descending obliquely, with posterior margin slightly narrower than anterior one, with a mediolongitudinal carina resulting into two flattened triangular tubercles posteromedially, the triangular tubercles projecting over posterior margin of tergum V, and posterolaterally with a spinose tubercle; tergum VI distinctly descending obliquely, with posterior magin distinctly narrower with a posteromedial diverging mediolongitudinal carina; anterolaterally with a small granule; tergum VII almost parallel-sided, slightly tapering towards the posterior; tergum VIII about as wide as VII but distinctly longer, more or less parallel-sided and slightly ascending; posterolaterally with a spinose granule and posteromedially with a pair of granules; IX about as wide as VIII with a distinct elongated and tectiform posteromedial crest, the crest not notched apically, apex narrow; posterior margin rounded; sides and crest of tergum IX granulose. Anal segment narrower than tergum IX and dorsally flattened; anteriorly with a tubercle medially, sublaterally with an oblique row of two tubercles reaching posterolateral angles; posterior margin straight but granulose. Subgenital plate with a mediolongitudinal carina, rounded, boat-shaped with widest part at about mid length; posterior rim dorsoventrally flattened, narrowing towards the posterior; apex rounded, almost reaching margin of tergum X. Abdominal sterna with a pair of minute granules posteromedially.

EGG ( Fig. 23 A–C ).

Measurements [mm]. Length: 3.4; width: 2.0; height: 2.5.

Egg capsule oval, slightly laterally compressed and brown. Operculum narrow, convex and strongly tapering towards the dorsal side of capsule; narrow margin visible in dorsal view. Ventral margin slightly wider and rounded. Capsule and operculum covered with long setae (about 0.3 mm) with a distal black three-hooked grapnel-shaped structure. Micropylar plate trilobate with one anterior expansion and with two posterior expansions. Margins of micropylar plate almost invisible. Anterior expansion parallel-sided, reaching margin of operculum. Posterior arms laterally projecting but margins obsolete. Micropylar cup small, black, cup-shaped and protruding.

Figures

Fig. 21. Orestes krijnsi sp. nov., holotype ♂. A, habitus, dorsal view. B. habitus, lateral view. C, habitus, ventral view. D, headand thorax, dorsal view. E, terminalia, dorsal view. F, terminalia anterodorsal view.G, terminalia, ventral view. H, terminalia, lateralview.I, head andthorax, lateralview.

Fig. 22. Orestes krijnsi sp. nov., paratype ♀. A, habitus, dorsal view. B, habitus, ventral view. C, head and thorax, dorsal view. D, terminalia, dorsal view. E, Terminalia anterodorsal view. F, terminalia, lateral view. G, habituslateral view. H, terminalia, ventral view. I, head andthorax, lateral view.

Fig. 23. Orestes spp., eggs. A–C, O. krijnsi sp. nov. A, lateral view. B, dorsal view. C, operculum. D–F, O. mouhotii (Bates, 1865) (photographs by F. Tetaert). D, lateral view. E, dorsal view. F, operculum. G–I, O. subcylindricus(Redtenbacher,1906)comb. nov. G, lateral view. H, dorsalview. I, operculum.

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

Fig.24. Orestes krijnsi sp. nov., adult pair in nature, Nui Chua N.P., 8.VIII.2014.