Genus ARRHENOPHAGUS Aurivillius

Arrhenophagus Aurivillius, 1888:144. Type species: Arrhenophagus chionaspidis Aurivillius, by monotypy.

Mymariella Risbec, 1951:402. Type species: Mymariella paralatoriae Risbec, by monotypy. Synonymy with Arrhenophagus by Annecke & Insley (1971:6,37).

Female. Length about 0.5-0.6mm.

Head dark brown with weak metallic coppery purple and dark blue or green reflections; transfacial suture pale yellow; antenna with radicle and scape pale yellow, pedicel and flagellum slightly dusky pale orange; thorax mostly dark brown, but mesopleuron sometimes orange-brown; mesoscutum and scutellum with weak metallic coppery purple and dark blue or green reflections; tegula pale orange, brown apically; legs pale orange, hind femur sometimes slightly dusky dorsally in apical half; wings hyaline; gaster brown, dorsally with weak coppery purple, dark blue and brassy reflections.

Head slightly shiny, with relatively deep, slightly irregular, transversely elongate, polygonally reticulate sculpture on frontovertex of mesh size mostly conspicuously larger than eye facet; temple and gena with relatively shallow, longitudinally elongate imbricate-reticulate to striate sculpture; ocelli forming an angle of about 115°; scape about 4X as long as broad; funicle 2- to 4-segmented, septa indistinct, segments strongly transverse and indistinct; clava relatively large, entire, with a strong, oblique, apical truncation; linear sensilla on clava only, distinct; eye separated from occipital margin by very nearly diameter of facet; malar sulcus absent; mandible with a single, elongate, apical tooth.

Thorax with polygonally reticulate sculpture on mesoscutum that is of similar depth to that on frontovertex, but composed of more rounded cells; notaular lines absent; scutellum about 1.1- 1.2X as broad as long and with slightly shallower, more longitudinally elongate sculpture than mesoscutum; tarsi 4-segmented; fore wing about 2.1X as long as broad, venation not reaching half way along wing, marginal vein about as long as broad, stigmal vein sessile, postmarginal vein absent, linea calva closed, filum spinosum present; tarsi 4-segmented.

Gaster with hypopygium very nearly reaching apex; ovipositor not exserted or hardly so; gonostyli freely articulated.

Male. Length about 0.5mm.

Generally very similar to female but for structure of antenna and genitalia. Antenna with a 4- to 6-segmented funicle, F6 largest, segments transverse, clava entire, flagellum clothed in long setae, longest about 3X diameter of segment; genitalia with aedeagus apically rounded, digiti varying from very short, to about 2X as long as wide, each with two teeth.

DISTRIBUTION. Cosmopolitan.

HOSTS. Primary endoparasitoids of a variety of armoured scale insects (Hemiptera: Diaspididae) and beesoniids (Hemiptera: Beesoniidae).

COMMENTS. Arrhenophagus is very similar to Arrhenophagoidea, both being structurally almost identical but can be separated by the number of tarsal segments, Arrhenophagus having only four whilst Arrhenophagoidea has five. These genera as the only members of the tribe Arrhenophagini.

IDENTIFICATION. Four species are known worldwide. Annecke & Prinsloo, 1974 (detailed treatment of chionaspidis and albitibiae); Tan & Chen, 2008 (description of longicalcaratus)

Key to Costa Rican species of Arrhenophagus

(Females)

1. Head in facial view (Fig. 10) clearly higher than broad, with clypeal margin strongly emarginate at base of each mandible; truncate surface of clava (Fig. 9) less than 0.6X as long as ventral surface of clava ............. chionaspidis Aurivillius (p. 29)

- Head in facial view as broad as high (Fig. 11), with clypeal margin hardly emarginate at base of each mandible; truncate surface of clava (Fig. 12) at least 0.8X as long as ventral surface of clava .................................................. albitibiae Girault (p. 30)