Mesagraecia larutensis sp. n.

(Figs. 1–3)

Material examined. Holotype: male (LAR.15.24), Peninsular Malaysia, Perak, Taiping, on Bukit Larut, circa N4.86184, E100.79276, 1056± 6.6 m, grassy, garden-like open area, grasses and herbs, 18 June 2015, 945-1053 h, coll. M. K. Tan, K. N. Kamaruddin, S. T. Toh, I. Abdul Rani (ZRC).

Discussion. This species also differs from the likely sympatric Mesagraecia laticauda (Karny, 1926). Although only the female of Mesagraecia laticauda was known, the pronotum and length of tegmen are visibly different (see key below). These morphological differences are unlikely sexually dimorphic as we do not observe these differences between the sexes of both Mesagraecia bicolor and Mesagraecia gorochovi.

Diagnosis. The male of this species differs from all known species of Mesagraecia by the tenth abdominal tergite being provided at apex with medial furrow and elongated lobes of both sides; those subacute lobes are pointing ventrad and are provided with a smaller tooth (pointing ventro-externally) near the medial-external margin; the epiproct is elongate tongue-shaped; the cercus is provided in midlength with a long internal process pointing ventrad and is at apex bifurcate into two subacute tooth-like processes (one longer than the other); the apical area of the cercus is laterally compressed and carries two short subapical teeth on internal surface. The subgenital plate bears two broad and stout, apically compressed styli.

Description. Habitus typical of genus (Fig. 1). Fastigium verticis conical, shorter than scapus; in frontal view rather well separated from fastigium frontis (Fig. 2 A). Frons shining with shallowly impressed dots (Fig. 2 A). Pronotum slightly saddle-shaped, rugose, disk broadly rounded into paranota, posterior area raised, flattened, shouldered and with a medial carinula (Figs. 2 B, 2C); transverse sulcus present but only feebly distinct, (sub-)interrupted in middle; anterior margin straight, posterior margin broadly rounded (Fig. 2 C); ventral margin of paranota subsinuate, sloping posteriorly, anterior angle broadly rounded, posterior angle angularly-rounded, humeral sinus distinct but not deep (Fig. 2 B). Fully winged, tegmen reaching hind knees of stretched legs (Fig. 1). Tegmen in about basal half with costal field widened, gradually narrowing into narrow apical area with parallel margins; apex truncated (Fig. 1 C). Prosternum without tubercles, at most feebly raised. Meso- and metasternum rather flat, lobes triangular with an apical obtuse cone. Procoxa with long spine, curved ventrad; mesocoxa without spinule but with tubercle. Profemur with 2 and 3 spines on ventro-external and ventro-internal margins; mesofemur with 3 spines on ventro-external margin; postfemur with 8 and 4 spines on ventro-external and ventro-internal margins. Ventral spines on pro- and meso-femora of subequal lengths. Knee lobes of profemur obtuse on external, subacute or angular on internal side; of mesofemur obtuse on external, spinose on internal side; of postfemur spinose on both sides.

Male. Stridulatory file on a broad, distinctly elevated socklet (Fig. 2 D). Stridulatory file on underside of left tegmen 2.4 mm long; gently curved in the middle; with 185 densely arranged teeth, with larger and broader teeth in the middle (Fig. 2 E). Mirror on left tegmen 2.0 mm long, 2.3 mm wide (Fig. 2 D). Tenth abdominal tergite with dorsal area very little prolonged, surface nearly flat with sloping and wide medial furrow (Fig. 3 A); apical margin in middle excised with truncate bottom and elongated lobes of both sides of excision (Fig. 3 B), lobes pointing ventrad with a smaller tooth (pointing ventro-externally) near the medial-external margin, both the lobes and teeth with subacute apices (Fig. 3 B). Epiproct elongated and tongue-shaped; dorsal surface feebly depressed (Fig. 3 B). Paraproct with tuberculate projection (Fig. 3 A). Cercus stout and cylindrical, gently curved; in midlength with a long internal process pointing ventrad, apex of internal process bifurcate into two subacute tooth-like processes (one longer than the other) (Figs. 3 A–D). Apex of cercus broadly truncated; with a short and subacute pre-apical external tooth pointing posterior-dorsad (Fig. 3 C); with an even shorter and obtuse tooth pointing internally on media-internal margin, anterior of the external pre-apical tooth (Fig. 3 A). Subgenital plate longer than wide; mainly in lateral areas and median carina setose; triangularly excised at base; in ventral view basal half wider than apical half (Fig. 3 D); about apical quarter curved dorsad (Fig. 3 C); upcurved area in apical view wide-roundly excised, internal margin slightly swollen in middle but without projection; stylus broad and stout, compressed apically. Titillators subfused at base, deeply excised in middle; compressed and each titillator supporting a large membranous sacculus (Figs. 3 E–G). Membranous part of sacculus at apex densely setose, particularly on external surface (Fig. 3 F).

Female. Unknown.

Coloration. Brown-grey. Frons and genae maculated greyish brown with light spots; ventral area of genae, clypeus and labrum yellowish brown; scapus and pedicellus infuscate and shining black except internal surface, flagellum indistinctly annulated. Pronotum generally greyish brown including light spots; with narrow irregular black lateral bands continued along posterior margin; pronotal disc with a fine medial longitudinal red line, with three pairs of black spots: along anterior margin, in middle and along posterior margin (much large and elongated), between pairs of spots two black irregular spots along midline (posterior spot larger than anterior one); pronotal lobe darker with more distinct light spots, margin also with fine red line. Abdominal tergites red dorsally, greyish brown with light spots laterally. Tegmen maculated. Hind wings dark infumated, anterior veins red. Legs yellow brown and maculated greyish brown; dorsal area of postfemur with large dark spots perforated with numerous small pale dots; posttibia with black spots ventrally.

Measurements (mm). BL = 27.2; BWL = 36.6, PL = 10.6, PW = 5.4, TL = 24.6, HFL = 22.9, HTL = 22.8.

Etymology. The species is named after the type locality, Bukit Larut.