Micrornebius mandai Tan

Tan, Ming Kai, 2014, New species of small scaly crickets of genus Micrornebius (Orthoptera: Mogoplistidae; Mogoplistinae) from Singapore, Zootaxa 3895 (1), pp. 117-126 : 122-123

Micrornebius mandai Tan , new species

( Fig. 3 )

Material examined. Holotype (male): Singapore, near Central Catchment Nature Reserve, near Mandai Lake Road, old secondary swamp forest, on tree bark, coll. M. K. Tan & H. Yeo, 1 June 2014 ( ZRC.ORT.1042, dry pinned).

Paratypes: 7 males, 1 female: Singapore, near Central Catchment Nature Reserve: 1 female ( ZRC.ORT.1043 dry pinned), near Mandai Lake Road, old secondary swamp forest, on tree bark, coll. M. K. Tan & H. Yeo, 1 June 2014; 2 males ( ZRC.ORT.1083, ZRC.ORT.1084, both dry pinned), near Mandai Track 15, disturbed and young secondary forest, on tree bark, coll. M. K. Tan & H. Yeo, 13 June 2014; 1 male ( ZRC.ORT.1169, in alcohol), near Central Catchment Nature Reserve, near Mandai Lake Road, old secondary swamp forest, on leaf litter, coll. M. K. Tan & H. Yeo, 14 August 2014; 3 males ( ZRC.ORT. 1148–1150, in alcohol), near Mandai Track 15, disturbed and young secondary forest, on tree bark, coll. M. K. Tan & H. Yeo, 13 September 2014; 1 male ( ZRC.ORT.1147, in alcohol), near Central Catchment Nature Reserve, near Mandai Track 15, disturbed and young secondary forest, on ground, coll. M. K. Tan & H. Yeo, 13 September 2014.

Diagnosis. This species differs from all known Micronebius species by male phallic complex with the presence of two forms of sclerotized apical plates and hyalinous pyriform discs. Similar to Micrornebius lineatus Ingrisch, 2006 from Sabah in male phallic complex with apical plates but differs by the presence of two forms of apical plates (paired plates rectangular with rounded edges, with surface densely granular and the third plate appearing more sclerotized with surface sparsely denticulate); medial valves distinctively sclerotized. Similar to Micrornebius insularis Ingrisch, 2006 from Thailand in medial valves of male phallic complex but differs by the presence of apical plates. Similar to Micrornebius malaya Tan & Nizam, 2013 from Peninsular Malaysia in ovipositor with dorsal and ventral apical valves diverging subapically before converging at apex but differs by dorsal apical valve feebly longer than ventral valve (dorsal apical valve much shorter than ventral valve in M. malaya ); also differs from M. malaya by male phallic complex.

Description. Habitus typical for the genus ( Figs. 3 A, 3B). Frontal rostrum about 4.4 times (n = 4) broader than scapus. Maxillary palps with apical (fifth) segment elongated triangular, fourth segment mostly cylindrical with apical part slightly widened, third segment cylindrical; apical segment slightly longer than fourth segment, apical and third segments of subequal length ( Fig. 3 C). Pronotum in male about 1.6 times (n = 8) longer than wide; with anterior dorsal margin straight and posterior dorsal margin broadly rounded, covering tegmen almost completely. Fore tibia with internal tympanum oval, external tympanum absent. Hind femur about 1.4 times (n = 8) longer than hind tibia; hind tibia 2.0 times (n = 8) longer than hind metatarsus.

Male. Last abdominal tergite and epiproct fused to a supra-anal plate; basally transverse, apically setose, apical half with a broad medial lobe, with apical margin truncated or broadly rounded ( Figs. 3 D, 3E). Phallic complex as shown in Figs. 3 F, 3G; with three large, brown, apical plates of two forms; paired plates rectangular to rhomboid, with surface densely granular; the third plate (appearing more sclerotized), hemi-elliptical (one end with rounded margin and the opposite end with straight margin) with surface sparsely denticulate ( Fig. 3 F). Below those plates with two smaller elongated pyriform (teardrop-shaped) discs which are largely hyaline except for external margin ( Fig. 3 F). Medial valves distinctively sclerotized; basal plate with two strongly sclerotized processes, between ejaculatory duct with two longitudinal branches connected by a basal plate; branches with basal half widened flattened to form a lamella and gently bent dorsad (when viewed laterally), distal half of branch rod-shaped and apex bent externally ( Fig. 3 G). Ejaculatory duct connected to basal plate of medial valves.

Female. Supra-anal plate setose, with two white lateral patches, apical margin rounded. Subgenital plate triangular, longer than broad, apical margin feebly emarginated in middle, setose throughout ( Fig. 3 H). Ovipositor with dorsal and ventral apical valves diverging subapically before converging at apex; dorsal valve slightly longer than ventral valve; dorsal valve with apex rounded, ventral valve more slender with apex more acute ( Fig. 3 I).

Colouration. Generally brown when without scales, scales brown and silvery in fresh specimens. Head yellow brown, eyes dark; scapus and basal antennal segments pale yellow brown and partly black; maxillary palps mostly brown, joints between segments a little pale. Pronotum generally yellow brown when naked, with brown and silvery scales ( Fig. 3 B). Mesosternum and metasternum pale yellow. Legs, including tarsi, generally pale with few dark brown variegation. Hind femora inner surface mostly naked, pale yellow at base and with brown scales near knees and upper margins; outer surface with brown scales. Hind tibiae black with yellow variegation. Abdominal tergites mostly black when naked with scales brown and silvery; abdominal sternites and subgenital plate brown ( Figs. 3 D, 3E). Cerci pale variegated with little brown scales ( Figs. 3 B, 3D, 3E). Ovipositor brown.

Measurements. See Table 2 .

Etymology. This species is named after type locality, Mandai ; noun in apposition. Life history. This species inhabits tree trunks, often hiding within crevices and beneath tree bark.

Figures

FIGURE 3. Micrornebius mandai sp. n.: male in-situ (A), male habitus in dorsal view (B), maxillary palps in lateral view (C), male abdominal apex in dorsal view (D, E), male phallic complex in dorsal view (F), medial valves of male phallic complex in dorsal view (G), female subgenital plate in ventral view (H) and ovipositor in lateral view (I). Scale bars: 1 mm (B), 0.1 mm (C – I).