Pediobius brachycerus ( Thomson, 1878 )

Cao, Huan-Xi, Salle, John La & Zhu, Chao-Dong, 2017, Chinese species of Pediobius Walker (Hymenoptera: Eulophidae), Zootaxa 4240 (1), pp. 1-71 : 30-31

12. Pediobius brachycerus ( Thomson, 1878)

( Fig. 11 )

Pleurotropis (Rhopalotus) brachycerus Thomson, 1878: 257 ; ♀♂. Lectotype ♀, LUZN, not examined; designated by Hansson, 1991: 35.

Mestocharis wilderi Howard, 1892: 298 ; ♀♂. Lectotype ♀, USNM, not examined; designated by Burks, 1966: 43. Synonymized by Peck, 1985: 682.

Pleurotropis wilderi ( Howard, 1892) , Crawford, 1912b: 179.

Pleurotropis aquatica Erdös, 1954: 350 ; ♂. Holotype ♂, HNHM, not examined. Synonymized by Bouček, 1965a: 56.

Rhopalotus brachycerus ( Thomson, 1878) , Erdös, 1956: 42.

Pediobius brachycerus ( Thomson, 1878) , Graham, 1959: 169 –204.

Pediobius wilderi ( Howard, 1892) , Peck, 1963: 234.

Diagnosis. Antenna stout with broadened and densely pubescent flagellum ( Figs 11 c, 11e). F3 transverse in male ( Fig. 11 c). Mesoscutum with very fine reticulation and metallic reddish reflections ( Figs 11 a, 11c), which for male reticulations of MLM distinctly elongate posteriorly. Notaular depressions distinct though not deep. Scutellum distinctly convex and reticulations distinctly dense and elongate in anterior half. Female gaster short ovate, with Gt1 occupying more than 2/3 length of gaster. In male, fore femur distinctly thickened.

Material examined. China, Guangxi: 1♀, Daxin , 30.III.1998, coll. Chao-Dong Zhu ; Heilongjiang: 2♀, Mudanjiang, Jingbo Lake , 16.VIII.1995, coll. Ju-Xian Lou ; Hubei: 2♂, Huanggang, Huangmei, 1978 ; 13♀, Wuhan , 10-20.IX.1983, coll. Jian Chen, ex. the egg sacks of Misumenops tricuspidatus (Fabricius) ; 3♀, Wuhan , VII.1983, coll. Jin-Kun Sheng, ex. spider egg sacks ; Inner Mongolia: 3♀, E-Erduosi, Engebei Ecological Demonstration Area , 30.VIII.2013, coll. Fei Xia ; Jiangxi: 1♀ 1♂, Nanchang , 09.X.1978, coll. Zheng-Xiang Ye, ex. spider egg sacks ; Sichuan: 3♀, YaAn , VI. 1974, ex. the pupa of Naranga aenesc Moore. Determined specimens compared ( ANIC): 3♀ 2♂, FRANCE: Rennes, 13.V.1982, coll. Rollardr Krespi, ex. spider egg-sacs, det. Bouček.

Biology. Pediobius brachycerus is mainly recorded from spider egg sacks of families Araneida, Clubionidae , Tetragnathidae and Theridiidae ( Noyes 2016) . As an endoparasitoid, it also can attack the larvae of Ichneumonidae (Hymenoptera) ( Bouček 1965a, Kamijo 1986b). In China, it is recorded as an endoparasitoid of egg sacks of some undetermined spiders.

Distribution in China. Guangxi, Heilongjiang, Hubei, Inner Mongolia, Jiangxi, Sichuan.

Remarks. Among all species in the facialis -group, P. brachycerus is most similar to P. grunini than the other three species. Two species found in China, P. narangae and P. tortricida , are more similar to P. facialis than P. brachycerus . These five species possibly could be divided into two different species groups, which P. brachycerus and P. grunini might belong to the other species group. Despite this, we include them in the same species group before we get more evidence. However, we suggest the name of facialis - instead of brachycerus - for this species group.

Compared with other three species of the facialis -group, P. brachycerus and P. grunini have face lacking coppery reflections. Pediobius brachycerus and P. grunini are similar not only in morphology but also in biology that they both parasitize the egg sacks of spiders. Bouček (1965a) discussed the similarities between P. brachycerus and P. grunini and the best features to separate P. grunini from P. brachycerus and P. facialis . Pediobius grunini differs from the latter two species by relatively slender antenna with sparse long setae ( Bouček 1965a, figs 43–45). Antenna of P. brachycerus is more transverse and densely pubescent than P. facialis . Reticulations on mesoscutum and scutellum are finer for P. brachycerus than those of P. facialis , P. narangae and P. tortricida . Scutellum of P. brachycerus is distinctly convex, while that of P. facialis is slightly convex. Female Gt1 of P. brachycerus exceeds mid-length of gaster, whereas it hardly reaching mid-length in P. facialis . Differences between their males are given in the key.

Figures

FIGURE 11. Pediobius brachycerus (Thomson, 1878). a: female, body in dorsal view; b: female, body in lateral view; c: male, body in dorsal view; d: female, fore wing; e: female, antenna; f: female, fore leg; g: female, mid leg; h: female, hind leg. Scale bar: a – c, 0.5 mm; d, 0.4 mm; e, 0.1 mm; f – h, 0.2 mm.