A new species of the rare chrysidid subfamily Loboscelidiinae from China: the third species of Rhadinoscelidia Kimsey, 1988 (Hymenoptera, Chrysididae)

Abstract Rhadinoscelidia delta Liu, Yao & Xu, sp. n. (Chrysididae, Loboscelidiinae) is described and illustrated based on two female specimens from Hainan province. It represents the first record of the genus Rhadinoscelidia Kimsey, 1988 for China. A key to the world species of this genus is given. All specimens are preserved in the Hymenopteran Collection, South China Agricultural University (SCAU).

Hosts of most species of this subfamily are unknown, but a few species are suggested to be parasitoids of Formicidae or Phasmatidae. Fouts (1922) suggested that Loboscelidiinae were probably myrmecophilous because they have the habitus of ants and the woolly appearance of the neck which is the characteristic of many myrmecophiles. Some species of Loboscelidia were inferred to be egg parasitoids of Phasmatidae (Hadlington and Hoschke 1959, Heather 1965, Riek 1970, Krombein 1983, Kimsey and Bohart 1990. However, there are no any host records of the genus Rhadinoscelidia. Most chrysidids are diurnal, but species of Loboscelidiinae are probably active during dusk or nocturnally based on their dark brown body and large ocelli (Kimsey and Bohart 1990).
Males of Loboscelidiinae are much more commonly collected than females (Kimsey and Bohart 1990). Recently, two specimens of the genus Rhadinoscelidia were discovered in Hainan, China, representing a new species, Rhadinoscelidia delta Liu, Yao & Xu, sp. n. It represents the fi rst record of this genus for China.

Materials and methods
Two specimens of the genus Rhadinoscelidia were collected in 2007 from Hainan. Type specimens are deposited in the Hymenopteran Collection of South China Agricultural University (SCAU).
Th e antenna, wings and legs on one side of the type specimen were cut off and mounted on a slide using Canada balsam. Specimens were examined and described using stereomicroscopes Leica MZ12.5 and Olympus SZ61. All pictures were made by Zeiss Imager A1 attached to a digital camera, CoolSNAP, and software Image-Pro Plus.
Abbreviations used in the descriptions as follows: POL= posterior ocellar line, the shortest distance between the posterior ocelli; MOD= mid ocellar diameter; OL= distance between middle and posterior ocelli; OOL=oculo-ocellar line, the shortest distance between the posterior ocellus and compound eye.
Morphological terminology and wing vein nomenclature are mostly based on that of Kimsey and Bohart (1990). However, mesoscutum and metasoma are used, respectively, for 'scutum' and 'abdomen'.
Diagnosis. Antenna with scape distinctly longer than head (Figs 1, 4); vertex sharply declivitous behind ocelli (Figs 3, 5); cervical projection of head with posterior shieldlike expansion clearly separate from rest of head (Fig. 3); fore wing ( Fig. 10 (Figs 4, 6) without transparent fl ange (the latter species with transparent fl ange), and frons ( Fig. 2) with median carina not forked at upper end (the latter with median carina of frons forked at upper end); it is also easily separated from R. malaysiae by fore wing venation restricted to basal 1/7 (Fig. 10) (the latter species with fore wing venation restricted to basal 1/13) and fi rst anal vein distinct (the latter with fi rst anal vein indistinct). Description. Holotype Female. Body length 2.3 mm; fore wing length 2.5 mm. Body shiny, with sparse setae.