Agrostocynips diastrophi (Ashmead)

Buffington, Matthew L. & Scheffer, Sonja J., 2008, North American species of Agrostocynips Diaz (Hymenoptera: Figitidae: Eucoilinae), parasitoids of Agromyzidae (Diptera): bionomics and taxonomy, Zootaxa 1817, pp. 39-48 : 43

Agrostocynips diastrophi (Ashmead)

Figures 1 A–F , 2 E

Diagnosis. Differs from A. clavatus by the lack of an indication of the mesoscutal keel at the anterior margin of the mesoscutum ( Fig. 1 F ) (distinctly present in all specimens examined of A. clavatus ); from A. robusta by the larger and more elongate scutellar plate ( Fig. 1 E–F ) (shorter and truncated posteriorly in A. robusta , Fig. 2 C ), as well as the presence of 7-8 perimeter teeth on the dorsal surface of the scutellar plate ( Fig. 1 E–F ) (4- 6 present in A. robusta ( Fig. 2 B ); further differentiated from A. robusta by the more pronounced orbital furrows on the inner margins of the eyes ( Fig. 1 C ) (rarely present in A. robusta ).

Rediscription. As in description of genus, with orbital furrows distinctly developed, running from lateral aspect of torulus to dorsal margin of malar sulcus; scutellar plate with 7-8 perimeter tubercals present on dorsal surface, usually in pairs, occasionally non-paired posteriorly; posterior margin of scutellar plate broadly rounded.

Material examined. Holotype. [first label] West Point, Neb[raska], [second label, folded] Diastrophus cuscataiformis [in Ashmead’s hand], [third label] Type No. 3280 U.S. N.M., [fourth label] Ganaspis diastrophi Ashmead , type [in Ashmead’s hand]. The holotype is a male, in poor condition, consisting of only the metasoma and hind legs glued to a card point. Deposited in USNM. Additional material. Several specimens from the following US states (deposited in UCRC and USNM): Arkansas, Florida, Illinois, Iowa, Kansas, Louisiana, Maryland, Michigan, Minnesota, Missouri, Oklahoma, Pennsylvania, South Carolina, Texas, Virginia and West Virginia.

Biology. Reared from the agromyzids Phytomyza sp., Phytomyza bipunctata Loew (host plant not recorded), as well as an unknown species of Agromyza on Panicum (switchgrass, Poaceae ). A specimen examined in the USNM perported to be reared from Phytomyza illicola requires confirmation. At the time of that collection (1919), it was not known that the linear miner and the blotch miner on I. opaca were two different species (see Kulp 1968). Further, no figitids have been reported from studies of parasitoids of P. ilicicola in Kentucky ( Potter and Gordon 1985), Delaware ( Kahn and Cornell 1989), Georgia ( Braman and Pendley 1993), and various locations in the eastern U.S. by the junior author (SJS, unpub. data).

Distribution. Southeastern United States (see material examined) and Northeastern Mexico (data not shown).

Figures

FIGURE 1. A – F, Agrostocynips diastrophi (Ashmead). A, habitus, female; B, close-up of head and mesosoma, female; C, SEM of female head, anterior view; D, SEM of female head, posterior view; E, SEM of female mesosoma, lateral view; F, SEM of female mesosoma, dorsal view.

FIGURE 2. A – D, Agrostocynips robusta (Ashmead). A, habitus, female; B, close-up of head and mesosoma, female; C, female mesosoma, dorsal view; D, forewing of female, ventral view. E, A. diastrophi (Ashmead), forewing of female, ventral view. F, sympatric holly leafminers on Ilex cassine: linear mine (l) of Phytomyza opacae Kulp contrasted with two blotch mines (b) of Phytomyza n. sp. 1, a host of A. robusta.