Anthracites inopinatus Gono & Tan, sp. nov.

(Figs 1, 2, 3A, 3C, 3E–H, 10)

Material examined. • ♂ Holotype; PHILIPPINES, Mindanao, Surigao del Sur, San Miguel, Barangay Siagao, Mt. Diwata Range; N8.979140 E126.00155, 50 m.a.s.l; 8 July 2024, 19h56; secondary forest, on shrub leaf near a stream; coll. A.III. A. Gono, A.E. Gono Jr & A.C.A. Gono (PNM).

Paratypes. • 1♂, 1♀; PHILIPPINES, Mindanao, Surigao del Sur, same locality; N8.97717 E125.98932; 50– 100 m.a.s.l; 9 July 2024, 21h57; beside ultramafic rocks on the shrubs near the stream; coll. A.III. A. Gono, A.E. Gono Jr & A.C.A. Gono (ZRC) .

Diagnosis. The new species is characterised by the black colouration, shapes of male cercus and subgenital plate and the titillators with two pairs of lateral sclerites distinctly separated (each sclerite triangular and pointing laterad and its apex acute). The new species is most similar to Anthracites furvuseques from Siargao Island by general colouration, the male stridulatory apparatus, the shape of the male cercus with two inner processes of similar sizes; but differs by the antennae red brown with some black rings (instead of almost wholly black), the fore and middle legs brown (instead of cream coloured) and knee area and anterior parts of tibiae dark but not clearly demarcated with the rest of the leg, the posterior femur with dorsum not black and with its knee area having a clear light-coloured ring just before apex (instead of wholly black), the cercus more triangular (instead of rectangular or rhomboid), its stridulatory area with a more swollen 1A, the stridulatory file with about 100 teeth (instead of 80–90 teeth). The new species can be most readily distinguished by the titillators with lateral sclerites more widely separated and without a distinct bridge between the sclerites, and the apex of each sclerite pointing laterad (instead of dorsad), and having lateral plates more sclerotized; the female subgenital plate with its posterior excision at the posterior end smaller.

The new species is also similar to Anthracites major from Surigao; but differs by the anterior and middle legs dark around its knees (unicolourous in A. major); the two inner processes of the male cercus similar in size and robustness (instead of the ventral one being decidedly heavier); its sternites and subgenital plate brown (instead of black).

Etymology. The species name refers to unexpected differences in the male titillators of the new species from Anthracites furvuseques from Siargao Island despite the overall similarities in the morphology of the abdominal appendages (e.g., tenth abdominal tergite, cercus and subgenital plate); inopinatus = unexpected, in Latin.

Description. Habitus of male as shown in Fig. 2. Fastigium verticis compressed laterally (Figs 2A–C), in dorsal view conical with a fine longitudinal groove, lateral ocelli before middle, apex truncated, shorter than scapus (Figs 2A, 2B). Frons shining with very few faintly impressed dots (Fig. 2C). Pronotum smooth to slightly wrinkled, disc broadly rounded into paranota, apical area rounded and faintly shouldered; anterior transverse sulcus short, posterior transverse sulcus longer and angularly rounded; anterior margin truncated but faintly concave in middle; posterior margin subtruncate (Figs 2A, 2B). Paranota with ventral margin broadly concave, posterior margin slightly sinuous (Fig. 2D). Acoustic spiracle large and elongated oval, completely covered by paranota (Fig. 2D). Tegmen micropterous, mirror area almost fully covered by pronotal disc, reaching only middle of 2nd abdominal tergite, with rounded apex (Figs 2A, 2B, 2D); hind wing present, but covered by tegmen. Prosternum with two long acute spines pointing nearly ventrad. Mesosternal and metasternal lobes conical with acute apices. Both tympana on anterior tibia slightly swollen with narrow slit. Anterior coxa with a long and curved spine (Fig. 2A). Femora with the following number of spines on ventral margins: anterior femur 5 external, 6 internal; middle femur 5 external, 2 internal; posterior femur 8 external, 2 internal. Knee lobes of anterior and middle femora obtuse externally and spinose internally; knee of posterior femur bispinose on both sides, longer than those of anterior and middle femora. Tibiae with the following number of spines on ventral margins: anterior tibia 7 external, 7 internal; middle tibia 10 external, 9 internal.

Male (Fig. 3). Mirror on left tegmen small, rhomboid, circa 1.2 times wider than long (Fig. 3A). Stridulatory file on underside of left tegmen straight; about 1.7 mm long; with about 102 teeth fairly regularly spaced throughout (Fig. 3B). Tenth abdominal tergite at posterior margin truncated, faintly emarginated in middle; posterior end in middle depressed; depression and posterior margin with setae (Figs 2E, 2F). Epiproct tongue-shaped. Cercus short and stout, dorso-ventrally compressed; distal part conical with obtuse apex; with two inner processes pointing inwards in distal half; both processes stout and triangular; dorsal process about as long as ventral (Figs 2J–J). Subgenital plate slightly longer than wide, with anterior margin concave, faintly converging lateral margins, apical margin deeply excised, excision truncated, at middle with stout lobe, with medial carina running from bottom of excision to centre of plate (Fig. 2K). Styli stout and long with apex rounded (Fig. 2K). Titillators (Figs 3E–H) separate, bases narrow band-shaped and pointing laterad, at middle strongly curved and most strongly sclerotized, apical end broadened, and apex broadly rounded with small weakly sclerotized spine; stiffened along rim and provided with two pairs of lateral sclerites (ls) distinctly separated; without distinct bridge connecting lateral sclerites; each sclerite triangular and pointing laterad and apex acute; with large membranous to weakly-sclerotized lateral plates (lp).

Female (Figs 1D, 1E, 2L–N). Tenth abdominal tergite short and transverse, deeply and widely emarginated in middle; forming two broadly rounded lobes (Fig. 2L). Epiproct broadly triangular with basal depression and broadly rounded apex (Fig. 2L). Cerci with apex pointing (Fig. 2L). Subgenital plate large, wider than long, roundly emarginated in middle, with two lateral angular lobes (Fig. 2M). Ovipositor long sabre-shaped; margins smooth (Fig. 2N).

Colouration. Body black with brown legs (Fig. 1). Face black, median ocellus yellow (Fig. 2C); scapus dark brown with tint of black and light brown; antennae red brown with black rings; maxillary palpi with basal three segments pale, apical and subapical segments dark with tint of pale; mandible black, clypeus pink-orange, labrum yellow-orange (Fig. 2C). Pronotum completely black (Figs 2A, 2B, 2D). Tegmen with lateral field bright yellow with irregular black spots, spots smaller closer to costal (anterior) margin; dorsal field mostly black, posterior of mirror also bright yellow with irregular black spots (Figs 2A, 2B, 2D, 3A). Spines on anterior coxa brown (Fig. 2D). Anterior and middle femora mostly yellow brown and brown respectively, apical part dark brown, knee area nearly black; anterior and middle tibiae pale brown with base and apex dark brown; fore and middle tarsi mostly black (Fig. 1). Posterior femur mostly brown, basal half with ventral parts more pale brown; apical part darkened, knee area black with white incomplete ring; ventral spines black (Fig. 1). Posterior tibia black near knee, otherwise pale brown with black dorsal spines (Fig. 1). Posterior tarsus black. Abdominal tergite black, near the posterior margin medially with a pair of lateral pale obliquely elongated spots (Fig. 2). Male tenth abdominal tergite and epiproct also black; brown setae on tenth abdominal tergite (Figs 2E–G). Cercus black with brown setae, apices of internal processes brown (Figs 2E–J). Sternites and subgenital plate pale brown or cream coloured (Figs 2K, 2M). Ovipositor mostly red brown (Fig. 2N).

Measurements (in mm). See Table 1.

Distribution (and type locality). PHILIPPINES: Mindanao: Surigao del Sur (Fig. 10).