Diglyphus subplanus (Erdös) Burks, 2012

Burks, R. A., 2012, Taxonomic studies on some little known genera of Palearctic Eulophidae and Pteromalidae (Hymenoptera: Chalcidoidea), Zootaxa 3487, pp. 24-40 : 28

Diglyphus subplanus (Erdös) comb. nov.

urn:lsid:zoobank.org:act:AEC85132-4B4B-44CA-B650-C654875186DB

( Figs 9–12)

Danuviella subplana Erdös, 1958: 212 .

Material examined ( HNHM). Holotype (♀): “ÁSVÁNY 1953.VI.1. ” / “DR. ERDÖS.” / “Dunai saiget füvein.” / “Hym. Typ. No. 4808 Mus. Budapest.”

Remarks. The historic criteria for distinguishing the monospecific genus Danuviella from the highly speciose genus Diglyphus focused mainly on the rugose petiole of Danuviella ( Bouček 1959; Peck et al. 1964). In the Australasian and Nearctic realms there are several apparently undescribed species with a more or less long and rugose petiole, forming a continuum of perceived variation between Danuviella and Diglyphus for this character and making generic identification highly arbitrary (Burks in prep.). Additionally, distinctness of the petiole is exaggerated in the holotype of D. subplana because the metasoma was partially separated from the mesosoma during card-mounting ( Fig. 10).

Ubaidillah et al. (2003) conducted a morphological phylogenetic analysis of Cirrospilini , where D. subplana differed from coded Diglyphus in some characters, usually agreeing with Diaulinopsis Crawford instead. Some results from this analysis also placed D. subplana with the very different genera Cirrospiloidelleus Girault and Oxycantha Surekha & Ubaidillah. A re-examination of the characters used in that study revealed that some are variable for some uncoded species of Diglyphus , including curvature of the cubital fold ( Gordh & Hendrickson 1979), transverse grooves on the frons, maxillary palp segmentation, large paired setae on the vertex, and length of the first metatarsomere relative to the second. Other codings for D. subplana differ from states present in the holotype, such as the presence of propodeal plicae, a single row of propodeal callus setae, and a single pair of large mesoscutal setae. This suggests that coding or specimen identification may have been incorrect for this species. Some coded differences between Danuviella and Diglyphus were not observable in the holotype of D. subplana , and others are only slightly differing states in characters that are variable within other cirrospiline genera. Therefore, current information does not indicate that any of these characters constitute sufficient grounds for keeping Danuviella separate from Diglyphus .

For these reasons it seems best to consider Danuviella a synonym of Diglyphus , with the new recognition that petiolar distinctness and sculpture are moderately variable within Diglyphus . This synonymy does not otherwise significantly affect the morphological definition or known host range of Diglyphus (parasitoids of leaf-mining Diptera). Diglyphus , with the inclusion of D. subplana , remains recognizable using features discussed in recent reviews ( Gordh & Hendrickson 1979; Schauff 1997; Gauthier et al. 2000).