Gnominthus milneus, Tan & Robillard, 2021

Tan, Ming Kai & Robillard, Tony, 2021, New taxa of the subtribe Lebinthina (Orthoptera: Gryllidae: Eneopterinae Lebinthini) from New Guinea and nearby islands, Zootaxa 5082 (6), pp. 583-599 : 585-588

Gnominthus milneus sp. nov.

Figs 1–3

Material examined. Holotype: PAPUA NEW GUINEA • ♂; Nowata , Milne Bay District; 600 m; July 1969; W. B. Hitchcock leg. ( ANIC14-036925 ) . Paratype: PAPUA NEW GUINEA • ♀; same locality and collector as holotype, molecular sample L201 ( ANIC14-036926 ) .

Type locality. PAPUA NEW GUINEA: Milne Bay District, Nowata .

Etymology. This species is named after the type locality, Milne.

Diagnosis. The new species differs from Gnominthus baitabagus Vicente & Robillard, 2015 by the colour patterns on the face, and by the male and female genitalia, the latter having paired pseudepiphallic apical lophi and different shapes of pseudepiphallic parameres and endophallic sclerite.

Description. Habitus similar in size and general shape to G. baitabagus ( Fig. 1 ). Vertex and fastigium yellow brown with numerous small dark spots. Dorsum of head yellow brown with six longitudinal dark bands at posterior end ( Fig. 2A ); back of eyes with a dark band. Scapes pale yellow brown, cream-coloured ventrally. Antennae orange brown. Face with a faint cream-coloured vertical band in the middle; fastigium verticis yellow brown with two dark spots; frons yellow brown with two dark spots and an oval dark patch above mouthparts ( Fig. 2B ). Clypeus cream-coloured; labrum cream-coloured with lateral parts black; mandibles entirely dark brown; maxillary palpi with segments cream-coloured, yellow brown at apices ( Fig. 2B ). Lateral parts of the head mostly dark brown ( Fig. 2C ). Pronotum dorsal disk yellow brown mottled with black, anterior margin faintly concave ( Fig. 2A ); lateral lobes dark orange brown with a pale ventro-anterior corner ( Fig. 2C ). Legs: FI–II light brown with faint brown spots; TI–II brown; tarsomeres 1 and 3 of each leg yellow basally then brown; FIII brown, knees dark brown; TIII homogeneously red brown. Abdomen red brown. Cerci brown.

Male: FW reaching base of forth tergite. FW colouration ( Fig. 2D ): Dorsal field cells mostly brown, veins generally brown or dark brown; CuA cream-coloured, M yellow brown, area between M and R dark, R brown. Lateral field cells dark; longitudinal veins brown. FW venation: harp vein strongly angularly sinuous, surrounding a small dark median bump. Anal area of dorsal field small, including two short cell alignments (e and f); apex of dorsal field obliquely rounded. Lateral field with Sc and 4 strong ventral longitudinal veins straight; Sc with one subapical bifurcation.

Male genitalia ( Figs 3A–C ): Pseudepiphallus triangular, elongate, its basal margin straight, posterior apex truncated with short paired lophi; lophi setose dorsally and ventrally with apices obtuse. Rami short, slightly longer than half the pseudepiphallus length, slightly converging apically. Pseudepiphallic parameres with a ventral lobe forming a triangular plate; and a dorso-lateral lobe transverse, pointing inwards with obtuse apex. Ectophallic apodemes parallel and long, reaching beyond anterior margin of pseudepiphallic sclerite. Ectophallic arc transverse and slightly curved. Ectophallic fold mostly membranous, triangular not reaching base of pseudepiphallic lophi. Endophallic sclerite narrowly Y-shaped, comprising a long anterior region and a triangular median expansion, fairly elongated lateral arms posteriorly not surpassing median expansion.

Female: FWs very short, not reaching the base of first tergite, very slightly overlapping ( Fig. 1C ). Cells of dorsal field brown, dorsal field with six strong orange longitudinal veins and very weak yellow transverse ones; lateral field with four longitudinal veins. Posterior corner between dorsal and lateral fields forming an acute angle, with oblong cream-coloured spot ( Fig. 2E ). Dorsal field apex oblique ( Fig. 2E ). Ovipositor rather short, apex faintly denticulate dorsally.

Female genitalia ( Fig. 3D ): Copulatory papilla conical, with a wide basal sclerite and a well-developed apex slightly sclerotized.

Measurements (in mm). Male holotype PronL = 2.6, PronW = 4.0, FWL = 3.5, FWW = 2.9, FIIIL = 8.7, FIIIW = 3.2, TIIIL = 7.0; female paratype PronL = 2.5, PronW = 3.8, FWL = 1.6, FWW = 1.5, FIIIL = 8.6, FIIIW = 3.3, TIIIL = 6.9, OL = 5.4.

Figures

FIGURE 1. Gnominthus milneus sp. nov. habitus. Male habitus in dorsal (A) and lateral (B) views; female habitus in dorsal view (C). Scale bar = 10 mm.

FIGURE 2. Gnominthus milneus sp. nov. morphology. Head dorsum in dorsal view (A); face in anterior view (B); head, pronotum and FWs in lateral view (C); male FW in dorsal view (D); female FW in dorsal view (E). Scale bar = 1 mm (A–C); 0.5 mm (D, E).

FIGURE 3. Gnominthus milneus sp. nov. male genitalia in dorsal (A), ventral (B) and lateral (C) views; female genitalia in ventral view (D). Scale bar = 1 mm.