6. Pediobius crassicornis (Thomson, 1878)

(Fig. 6)

Pleurotropis crassicornis Thomson, 1878: 255; ♀. Holotype ♀, LUZN, not examined.

Asecodes crassicornis (Thomson, 1878), Schemiedeknecht, 1909: 436.

Pleurotropis howardi Crawford, 1910: 23; ♀. Lectotype ♀, USNM, not examined; designated by Bouček & Askew, 1968: 90. Synonymized by Kamijo, 1977: 16.

Asecodes albitarsis Ashmead, 1888: 103; ♀. Holotype ♀, USNM, not examined. Synonymized by Peck, 1985: 663.

Pleurotropis albitarsis (Ashmead, 1888), Essig, 1926: 820.

Holcopelte tarsalis Ashmead, 1894: 341; ♀♂. Lectotype ♀, USNM, not examined; designated by Burks, 1966: 40. Synonymized by Peck, 1985: 663.

Horismenus tarsalis (Ashmead, 1894), Schmiedeknecht, 1909: 433.

Pleurotropis ashmeadi Crawford, 1912b: 177 . Replacement name for Pleurotropis (= Asecodes) albitarsis (Ashmead, 1888) . Synonymized by Peck, 1985: 663.

Pleurotropis tarsalis (Ashmead, 1894), Crawford, 1912b: 178.

Pediobius tarsalis (Ashmead, 1894), Reeks & Smith, 1956: 572.

Pediobius howardi (Crawford, 1910), Bouček & Askew, 1968: 90.

Pediobius crassicornis (Thomson, 1878), Peck, 1985: 663.

Diagnosis. MLM reticulate, and its posterior margin strongly emarginate and slightly raised, separated from the base of scutellum with a distinct, narrow semicircular hole (Figs 6 a, 6c). Notauli distinct; notaular depressions deep with inner margins slightly step-like, and almost smooth. Inner corner of axilla depressed. Scutellum has anterior median one-third with striations evanescent such that almost smooth, and has longitudinal striation at sides that merging to coarse reticulation posteriorly (Figs 6 a, 6c). Dorsellum short, rounded apically.

Material examined. CHINA, Hebei: 15♀ 6♂, Sanhe, 29.IX.2006, coll. Yan-Long Zhang, ex. Hyphantria cunea (Drury) on Populus adenopoda Maximowicz (Salicaceae) ; Inner Mongolia: 2♂, Chifeng (as Zhaomeng before), Beiwazi, 11.VIII.1978, coll. Gui-Wen Wang, ex. Lasiocampidae sp. ; Jilin: 8♀, Baicheng, Da-An, An- Guang, 15.VIII.1986, coll. Yu-Zhi Niu, ex. Clostera anachoreta (Fabricius); 1♀, Baicheng, Da-An, 15.VIII.1986, coll. Ya-Zhi Zhao, ex. the pupa of Clostera anachoreta . O ther examined material (CAFB): 2♀ 1♂ , CHINA, Hubei, Gongan, I–III. 2001, coll. Zhong-Qi Yang, ex. Micromelalopha troglodyta (Graeser) . Determined specimens compared (ANIC): 1♀ , England, Suffork Barton Millis, 07.IX.1997, coll. J. S. Noyes, det. Bouček .

Biology. Pediobius crassicornis has been recorded as either a primary or a secondary parasitoid (Noyes 2016). Chinese specimens deposited in IZCAS were reared from two species of moth, Hyphantria cunea (Drury) ( Lepidoptera: Arctiidae) attacking Populus adenopoda Maximowicz (Salicaceae) and Clostera anachoreta (Fabricius) ( Lepidoptera: Notodontidae). Besides, P. crassicornis was recorded from the pupae of Micromelalopha troglodyta (Graeser) ( Lepidoptera: Notodontidae) by Yang et al. (2015).

Distribution in China. Hebei, Hubei, Inner Mongolia, Jilin.

Remarks. One male of P. crassicornis in IZCAS, reared from Hyphantria cunea (Drury), has the gaster pointed apically, and Gt1 not covering most length of gaster and just reaching mid-length. It is possibly an error that the male of P. crassicornis has four funicular segments stated by Bouček (1965a) (pages 11, 42), because we found only three funicular segments in Chinese males and Peck (1985) also stated that P. crassicornis has 3 funicular segments. Specimens of P. crassicornis in IZCAS, MLM are coarsely rather than finely reticulate and the median basal smooth area of scutellum is smaller, compared with one female of P. crassicornis determined by Bouček.

Pediobius crassicornis is very similar to P. elasmi by characters as given in the diagnosis of crassicornis - group. In spite of this, some characters are reliable to separate P. crassicornis from P. elasmi, such as reticulate MLM and indistinctly protruding apex of dorsellum (as given in the key). Bouček (1965a) stated that this species was closely allied to P. foveolatus and P. imbreus Walker (under the name of P. detrimentosus (Gahan)) within European Pediobius species. However, P. imbreus is close to P. pyrgo instead of P. crassicornis . Although P. crassicornis seems closely allied to P. foveolatus, we regard them as belonging to two different species groups that probably are closely related.