Idris fusciceps Johnson & Chen

Johnson, Norman F., Chen, Huayan & Huber, Bernhard A., 2018, New species of Idris Foerster (Hymenoptera, Platygastroidea) from southeast Asia, parasitoids of the eggs of pholcid spiders (Araneae, Pholcidae), ZooKeys 811, pp. 65-80 : 65

Idris fusciceps Johnson & Chen sp. n. Figures 5, 9, 13

Description.

Body length: 0.58-0.66 mm.

Head color: light brown. Mesosoma color: brownish yellow, contrasting with darker color of head. Metasoma color: brownish yellow.

Head shape in frontal view: ovoid, distinctly wider than high. Head width/mesosomal width: 1.17-1.24. Sculpture of upper frons, vertex: pustulate. Position of lateral ocellus: separated from inner orbit of compound eye by approximately 1 ocellar diameter. Central keel of frons: present. Length of central keel of frons: extending dorsally one-third distance to median ocellus. Speculum: present. Striae on lower frons: absent. Setation of compound eyes: eyes distinctly setose.

Size of A3: distinctly smaller than A2. Shape of A3: width greater than length.

Length/width mesoscutum: 0.64-0.72. Sculpture of mesoscutum: finely reticulate, setal bases pustulate. Notauli: present, short. Sculpture of mesoscutellum: finely reticulate, setal bases pustulate. Sculpture of metascutellum: rugulose. Propodeal armature: lateral propodeal area produced dorsomedially into small tooth.

Wing development: fully developed, macropterous. Fore wing patterning: fore wing hyaline throughout. Marginal fringe of fore wing: present, short. Length of bristles on submarginal vein: elongate, extending beyond costal margin by distance more than half their length. Basal vein: well-defined, straight, lightly pigmented. Length of stigmal vein: elongate, extending nearly to middle of fore wing. Length of postmarginal vein: extremely short, subequal in length to marginal vein.

Metasoma length/body length: 0.44-53. Sculpture of T1: longitudinally costate. Sculpture of T2: longitudinally costate in medial third, finely reticulate along lateral margin, elsewhere smooth. Sculpture of T3: finely reticulate, with weak irregularly longitudinal rugulae medially. Length T3/length T2: 1.56-1.60. Sculpture of T4-T5: finely reticulate basally, smooth apically. Setation of T3: lateral thirds of tergite moderately setose through, median third nearly glabrous, with sparse apical transverse band of setae.

Diagnosis.

In the keys of Kozlov and Lê (1987) and Lê (2000), this species comes closest to I. oobius Kozlov & Lê, particularly in the weak sculpture of T3 and the uniform coloration of the wings. This species is distinguished from I. oobius by the extremely short A3 in comparison to the length of A2. It may be distinguished from the other reared species described herein by the presence of notauli and the dark-colored head; among other morphologically similar species of Idris it may be recognized by its COI sequence.

Host.

Belisana khaosok Huber (ZFMK, Mal331= Ar 19649) ( Araneae : Pholcidae ) (Fig. 20).

Etymology.

The specific epithet refers to the darker color of the head in comparison with the mesosoma and metasoma. It is to be treated as a noun in apposition.

Material examined.

Holotype, female: THAILAND: Krabi, ~9 km N Krabi town, degraded forest between plantation and rocks, 75 m a.s.l., 8°09.9'N 98°51.7'E, 7.III.2015, B. A. Huber & B. Petcharad, ex egg of Belisana khaosok Huber. OSUC270824. Paratypes: THAILAND: 8 females, 1 male with same data as holotype (OSUC270825-270827, 420839-420843, 627626).