Conostigmus ambiguus ( Ashmead, 1893 )

Trietsch, Carolyn, Mikó, István, Ezray, Briana & Deans, Andrew R., 2020, A Taxonomic Revision of Nearctic Conostigmus (Hymenoptera: Ceraphronoidea: Megaspilidae), Zootaxa 4792 (1), pp. 1-155 : 23-24

Conostigmus ambiguus ( Ashmead, 1893)

Figs. 11 , 12

Species Comments and History. Ashmead (1893) described this species from a male and female specimen, stating that the male antennae are distinct because the pedicel and first flagellomere together are shorter than the scape. However, this is true in the majority of Conostigmus species (exceptions include Conostigmus abdominalis and related species). The female antennae are described as having the pedicel and first flagellomere of equal length ( Ashmead, 1893), but this also occurs in females of C. bipunctatus and C. lepus , among others.

Masner and Muesebeck (1968) designated a female lectotype and male allolectotype at the USNM. Both specimens are complete but very poorly glued, and the excess glue obscures some characters. It is thus unclear whether the male and female belong to the same species. While both specimens have two mandibular points and a facial pit, the female appears to have a sternaulus while the male does not. The two specimens also have different collecting events, with the male collected in Arlington, Virginia, and the female collected in Washington, D.C., matching the original description given in Ashmead (1893).

Ashmead (1893) noted that this species closely resembles C. laeviceps , and differs in that C. ambiguus is larger and has differences in the sculpturing and lengths of the flagellomeres. Conostigmus laeviceps also has an elongate sternaulus (exceeding 3/4 of mesopleuron length at level of sternaulus). The female lectotype of C. ambiguus does not have an elongate sternaulus, and the male allolectotype does not have a sternaulus, so neither of these specimens belong to C. laeviceps . The male allolectotype has a yellow propleuron similar to the males of C. nigrorufus or C. rufoniger , and male genitalia characters are needed to confirm whether these are the same species.

Unfortunately, this Conostigmus species lives up to its name. We consider this species as a species inquirenda until more specimens can be found, and the genitalia of a male matching the female can be dissected and compared.

Material Examined. Lectotype female: USA: USNMENT01339747 ( USNM) . Paralectotypes (1 male): USA: Virginia : 1 male. USNMENT 01212995 ( USNM) .

Figures

FIGURE 11. Conostigmus ambiguus (Ashmead, 1893) in dorsal view. A. Male allolectotype (USNMENT01212995). B. Female lectotype (USNMENT01339747).

FIGURE 12. Conostigmus ambiguus (Ashmead, 1893) in lateral view. A. Male allolectotype (USNMENT01212995). B. Female lectotype (USNMENT01339747). Abbreviation: sternaulus (ste).