Orthocentrus anguillae Broad

Veijalainen, Anu, Broad, Gavin R. & Sääksjärvi, Ilari E., 2014, Twenty seven new species of Orthocentrus (Hymenoptera: Ichneumonidae; Orthocentrinae) with a key to the Neotropical species of the genus, Zootaxa 3768 (3), pp. 201-252 : 206-207

Orthocentrus anguillae Broad , sp. nov.

Figs 1 A, 6 A, 8 A, 11 A, 13 A.

Fore wing length c. 2.3 mm (difficult to measure, wings fairly crumpled on unique specimen).

Whole body, especially head, laterally extremely flattened.

Face medially 0.8x wider than high; most of head polished, impunctate, face with shallow punctures and coriaceous centrally, on protruding surface, eyes not setose, dorsal ridge of face inbetween antennal sockets very short, without a low ridge; face in profile almost straight but slightly rounded dorsally, edge of clypeus straight, antennal sockets on a high shelf; malar space with narrow, shallow, microsculptured sulcus; maxillary palp short, reaching to about fore coxa. In dorsal view, head deeply concave posteriorly, temples distinct, posterior ocelli distant from eye by c.0.7x ocellar diameter, anterior ocellus separated from eye by slightly more than ocellar diameter, ocellar-ocular groove present as vague impressions. Antennal sockets touching each other; antenna rather thick, curled, with 21 similar-sized and transverse flagellomeres which not gradually shortening towards apex; basal flagellomere 1.3x as wide as high and about 1/4 of the length of scape; scape parallel-sided.

Mesosoma smooth and polished except for fine striations over middle c.0.3 of pronotum (anterior of mesopleuron not visible in unique specimen); posterior portion (partly obscured by glue) of metapleuron and most of propodeum (except for antero-lateral area in front of spiracle) coriaceous; mesoscutum lacking notauli; in profile, scutellum not particularly high, metapleuron not convex; propodeum with complete posterior transverse and median longitudinal carinae, latter stronger posteriorly, spiracles small.

Legs all flattened, broad; coxae and femora polished, tibiae and tarsi coriaceous-granulate; hind coxa 1.1x as long as first tergite, hind femur 2.8x as long as high, hind tibia 3.7x as long as apically wide; tibiae dorsally with many stout, spine-like setae.

Wings narrow, cells thus comparatively long and narrow; fore wing with areolet closed but 3rs-m weak, areolet longer than high, with 2rs-m shorter than 3rs-m, 2m-cu meeting areolet at apical 2/3, vein Rs straight; hind wing vein cu-a angulate below middle.

First tergite elongate, 2.1x as long as apically wide, in dorsal view, laterally incurved posterior to spiracles; coriaceous to faintly rugose except polished very apically, with two strong median longitudinal carinae detectable over most of length, with faintly indicated, obliguely transverse impressions at about mid-length. Second tergite cannot be measured as individual with metasoma flattened; anterior half coriaceous to striate; basal thyridia oval. Remainder of metasoma polished, lacking thyridia, metasoma flattened laterally from third tergite. Ovipositor not visible; ovipositor sheath truncate apically, with numerous setae slightly longer than sheath width, setae not conspicuously backwards-pointing.

Body largely setose except eyes, with setae comparatively long and sparse, but shorter and denser on mesoscutum; very few setae on pronotum, mesopleuron, metapleuron, metasomal tergites and posterior sides of coxae.

Brown except mouthparts and sternites creamy to light brown, scape, pedicel and basal two flagellomeres dull yellow, fore and mid legs largely yellow, hind leg darker orange, especially coxa, with tibia darkened apically.

Male. Unknown.

Biology. Hosts unknown. The single specimen was collected in southern Brazil. The flattened body and thick antennae of the female suggests that it must emerge from or enter into very confined spaces.

Etymology. Named after the Latin for ‘eel’, after its conspicuous lateral compression.

Comments. Compared with all other species with antennae on a high shelf and glabrous eyes, except for O.

shieldsi , the face is markedly laterally compressed. Very similar to O. shieldsi , which was also collected in ‘Nova Teutonia’ in Brazil, but the present species is less extremely flattened with smaller ocelli and a less sculptured face. In addition, the propodeal carination is more complete in O. anguillae (e.g. median longitudinal carinae present).

Material examined. Holotype female: ‘ Brazil, Nova Teutonia, 27º11’ B, 52 º23’L, VI.1935, Fritz Plaumann’ ( BMNH).

Figures

FIGURE 1. Lateral views: Orthocentrus shieldsi species-group (in part). A: anguillae, B: pentagonum, C: concrispus, D: hispidus, E: quercus, F: shieldsi. Scale 0.5 mm.