Diachasmimorpha hildagensis (Fischer)
Both D. hildagensis and D. mexicana were described from single male specimens collected in the state of Mexico and the Distrito Federal, respectively, and unassociated with either hosts or host plants. Both have relatively small eyes, but are readily separated from one another on the basis of head coloration. Associating the name hildagensis with the many dark-headed specimens available for study, however, has been considerably more challenging. Reared material, representing over 50 specimens kindly made available to us by Allen Norrbom, Martin Aluja, and Juan Rull, provides clear evidence of sexual dimorphism in eye size as well as variation in ovipositor length associated with different hosts and host plants. This material has been especially critical for understanding color patterns and associating males with females. Based primarily on eye size and body size, the holotype of D. hildagensis is closest to the series of three specimens listed above under “other specimens examined,” that emerged from puparia of O. latifrons infesting fruits of S. brachycarpum.
Biosteres (Parasteres) hildagensis: Fischer 1967a: 5 (generic transfer).
Parasteres hildagensis: Fischer (1971): 33 (generic transfer); Fischer 1977: 880-883 (key, redescription).
Diachasmimorpha hildagensis: Wharton et al. (2012): 36-43 (generic transfer).
Specimens reared from Oedicarena latifrons (Wulp) vary as follows relative to the holotype: clypeus length/height ratio 2.6-2.8; eye/temple ratio, lateral view, 1.3-1.4 (males), 1.55 (female); antenna with 46-48 flagellomeres; 2RS/3RS ratio 0.95-1.0; ovipositor sheath 2.5 times longer than the mesosoma (Fig. 8); mesosoma length 1.85-1.9 mm (male), 2.0 mm (female); one male with T1 dorsal carinae absent over posterior 0.5 and mandible, clypeus, face, and hind coxa more extensively orange; female with outer surface of hind coxa completely pale (dark medially), mandible, clypeus and lower part of face more extensively pale than in holotype.
This species is slightly larger and has a smaller eye than both of the similarly-colored species Diachasmimorpha martinalujai Wharton and D. norrbomi Wharton. Based on the single female reared from O. latifrons, D. hildagensis also has a much longer ovipositor than D. norrbomi. The ovipositors of D. hildagensis and D. martinalujai are similar in length. In D. hildagensis and D. martinalujai, the notaulus consistently extends anteriorly to the margin of the mesoscutum (Fig. 2) whereas in D. norrbomi, the notaulus usually does not (Fig. 10). Color variation in the specimens reared from O. latifrons is similar to that in the paratype series of D. martinalujai and D. norrbomi. Both D. hildagensis and these two more recently described species are similar in having the head mostly dark in contrast to the orange heads of D. mexicana and D. sanguinea, the other two members of this species group. The holotype of D. hildagensis exhibits subsurface discoloration on the metasoma, but the tergites are all entirely orange.
Other specimens examined: 2 females, 1 male, Mexico, Mexico, Rt 890, km 9, 6 km W Lago Zempoala, 2.×.1991, A.L. Norrbom, reared from Oedicarina latifrons infesting fruits of Solanum brachycarpum (91M14B) (TAMU, USNM).