Ocellarnaca disjuncta, 2018

Ingrisch, Sigfrid, 2018, New taxa and records of Gryllacrididae (Orthoptera, Stenopelmatoidea) from South East Asia and New Guinea with a key to the genera, Zootaxa 4510 (1), pp. 1-278 : 74-78

Ocellarnaca disjuncta sp. nov.

Figs. 21 A–B, 22A–B, 23A–C, 24A–B

Material examined. Holotype (male): Vietnam: Prov. Vinhfu, Tam Dao N.P., (21°31'N, 105°33'E), 25– 30.vii.2011, leg. J. Constant & J. Bresseel (I.G. 31.933)—(Brussels RBINS).

Other specimens: same data as holotype— 2 females, 3 males (paratypes) (Brussels RBINS).

Diagnosis. The new species is similar to O. brevicauda Li et al. 2014 with regard to the appendages of the male ninth abdominal tergite that are lateral instead of in middle of apex as in other species of the genus and the seventh sternite female has no medial process but instead the lateral angles produced. It differs from O. brevicauda by a longer lateral appendage of the ninth tergite that is distinctly curved and at tip with serrate margin and by the female subgenital plate that has distinct full-length bulging lateral margins separated from disc by a distinct furrow and the apical margin has a wider concave excision, additionally the seventh sternite has distinct compressed apico- lateral expansions and a wide and deep excision in between with subtruncate bottom while in the subgenital plate of O. brevicauda the lateral bulges are only indicated at very base and the apical excision is narrow while the seventh sternite has the apical margin as whole concave with rounded lateral angles.

Description. Rather short and stout species. Head: Face ovoid; forehead nearly smooth with some scattered impressed dots and very fine transverse riffles; fastigium verticis moderately wider than scapus, separated by a transverse suture from fastigium frontis; ocelli very distinct, light yellow; median ocellus very large; subocular furrow indistinct ( Fig. 22A ). Abdominal tergites two and three with stridulatory pegs.

Wings just reaching hind knees or little shorter ( Figs. 21 A–B). Tegmen: Radius with two branches: only RS forked once more near tip; media anterior has a common stem with radius, arising as first posterior branch of R before end of basal half; media posterior absent; cubitus anterior undivided; cubitus posterior undivided, free throughout; with 5 Anal veins plus a short and weak incomplete vein at hind margin of tegmen.

Legs: Fore coxa with a large spine at fore margin; fore and mid femora unarmed; fore and mid tibiae with four pairs of large ventral spines and one pair of smaller ventral spurs; hind femur with 6–12 external and 10–14 internal spines on ventral margins; hind tibia with spaced spines on both dorsal margins, ventral margins with one preapical spine; with 3 apical spurs on both sides.

Coloration. General color medium or reddish brown without distinct pattern except for wings; hind femur partly lighter towards base. Face uniformly reddish brown except for light ocelli; mandibles black, at base brown. Tegmen dark brown with light brown veins and veinlets adorned by whitish bands; hind wing dark brown with light brown veins and veinlets adorned by whitish bands, around cross-veins very conspicuous.

Male. Ninth abdominal tergite globular, apical surface at apex with wide but short excision, towards lateral margin with a short little conspicuous lobe, at latero-ventral angle extended into a small cylindrical, towards tip upcurved process with obtuse tip; directly mediad of that process with a tiny styliform projection. Tenth abdominal tergite running as a narrow band across the apical excision of the ninth tergite ( Figs. 23 A–B). Epiproct very small, hanging down from middle of tenth tergite; paraproctes forming large vaulted plates from internal margin of bases of cerci. Subgenital plate wider than long, lateral margins convex, apical margin substraight, faintly undulated; surface in midline in apical half with a depression; styli inserted at apico-lateral angles ( Fig. 23C ).

Female. Seventh abdominal sternite in baso-central area membranous, lateral margins widening posteriorly, margins in basal area concave, near tip convex; at apex with a wide excision with bottom of excision subtruncate in middle, laterally concave, tips of lateral projecting areas obtuse. Subgenital plate with sub-parallel, little concave lateral margins, wide apical margin on both sides obliquely truncate, in middle concave; surface along lateral margins little bulging, wide central area somewhat elevated ( Figs. 24 A–B). Ovipositor in subbasal area strongly upcurved, afterwards almost straight, lateral surface with longitudinal furrow; margins approaching till about middle of upcurved area then diverging again, before tip little swollen; tip subobtuse ( Fig. 22B ).

Measurements (4 males, 2 females).—body w/wings: male 27–28, female 26–28; body w/o wings: male 21– 25, female 24–26; pronotum: male 5.8–6.0, female 5.5–6.0; tegmen: male 17–20, female 18–19; hind femur: male 12.5–14.0, female 13–19; tegmen width: male 7.5, female 7; antenna: male 75–130, female 110–115; ovipositor: female 8–9 mm.

Etymology. The name refers to the widely separated hooks of the male ninth abdominal tergite; from Latin disjuncta (distant, separate).

Figures

FIGURE 21. Genus Ocellarnaca: Habitus dorsal view: A–B, O. disjuncta sp. nov. male holotype (A) and paratype female (B); C–D, O. fusca sp. nov. freshly molted female (C) and female holotype (D); E–F, O. angulata Gorochov, 2004 male (E) and female (F); G–I, O. braueri (Griffini, 1911) male (G) and female (H); male from Brunner collection BrW24.404 (I); J–K, O. wolffii (Krausze, 1906) det. Karny: male in NHMW (J), and female in BMNH labeled "allotype" (K). Scales 10 mm.

FIGURE 22. Genus Ocellarnaca: A–B, O. disjuncta sp. nov. holotype (A) and paratype (B); C–F, O. fusca sp. nov. light female (C) and holotype dark female (D–F); G–H, O. braueri (Griffini, 1911); I–L, O. wolffi (Krausze, 1906) male (I–J) and female "allotype" (K–L); M–N, O. angulata Gorochov, 2004 male (M) and female (N).—Face (A, C–D, G, I, M), ovipositor (B, F, L, N); abdominal apex in lateral view (E), habitus lateral view (H, K), male abdominal apex in oblique apical view (J). Scales 10 mm (habitus), 5 mm (ovipositor), 1 mm (face).

FIGURE 23. Genus Ocellarnaca: A–C, O. disjuncta sp. nov.; D–F, O. angulata Gorochov, 2004; G–I, O. braueri (Griffini, 1911).—Male abdominal apex in oblique apical (A), apical (D–E, H), dorso-apical (G), lateral (B), ventro-lateral (C), and ventral view (F, I).

FIGURE 24. Genus Ocellarnaca: A–B, O. disjuncta sp. nov. paratype; C–D, O. fusca sp. nov. holotype; E, O. angulata Gorochov, 2004; F–G, O. braueri (Griffini, 1911) small female (F) and large female (G); H, O. wolffi (Krausze, 1906).—End of female abdomen with seventh sternite, subgenital plate and base of ovipositor in ventral (A, F–H), lateral (B), and anteriorventral view (C).