Dryinus argentinus Olmi, 1984

Coelho, Beatriz W., Aguiar, Alexandre P. & Engel, Michael S., 2011, A survey of Dryinidae (Hymenoptera, Chrysidoidea) from Caxiuanã, Amazon Basin, with three new taxa and keys to genera and species, Zootaxa 2907, pp. 1-21 : 7-9

Dryinus argentinus Olmi, 1984

( Figs 6–9 )

Dryinus argentinus Olmi, 1984: 846 ; Virla & Olmi 1998: 25; Olmi 1999: 14; Olmi et al. 2000: 150. Types in AMNH, AEIC, Olmi Collection.

Comments. This species is quite similar to D. striatus (Fenton) . Olmi’s key to the neotropical species (1984) separates them based solely on the color of the pronotum. The overall structure of the chela does seem sufficiently distinct from the illustrations provided by Olmi (1984), but is nonetheless somewhat intermediate for the Caxiuanã specimens of these two species. These same specimens show, however, quite distinct and consistent color patterns for each respective species. The degree and consistence of the differences hold even for specimens of each species from the same collecting event, e.g., a couple of females of D. argentinus and D. striatus from the trail at Tijucaquara, 15–18.XI, YPT, one labelled P05036 and the other P05038, which are trail points about 400 m apart from each other. It seems therefore clear that a more in depth investigation might be necessary to safely establish the identity of these two species. Proposing a synonymy might be premature at this time.

For the specimens found at Caxiuanã, D. argentinus differs by showing a light-colored pronotum (vs. dark-colored in D. striatus ), stripped metasoma (vs. fully darkened) (best seen with unaided eye), head in frontal view dark brown at the very top, behind and lateral to the posterior ocelli, then mostly light brown, ventrally whitish ( Fig. 8 ) (vs. mostly uniformly dark brown above base of antennae, whitish along eye margin and centrally, generating a Wpattern, Fig. 20 ); also with a few color pattern differences on the legs ( Figs 7 , 9 vs. 18, 19).

Also similar to D. guyanensis Olmi , from which it can be separated, as pointed by Olmi (1999), by the antennal segment 3 about 4 × segment 2 (vs. 10 × in D. guyanensis ) and about 2 × segment 4 (vs. 3 × in D. guyanensis ), and distal part of stigmal vein slightly shorter than proximal part (vs. much longer in D. guyanensis ).

Material examined. 15 specimens. BRAZIL: 15 Ƥ ( MPEG, at MZSP and UFES), PA, Melgaço, Caxiuanã, YPT, A.P. Aguiar & J. Dias. Trail at igarapé Ararua, 18–21.XI.2003, P05073. Trail at Estação Científica Ferreira Pena, 13–16.XI.2003, P05005; 16–19.XI.2003, P05050; 19–22.XI.2003, P05093; 22–25.XI.2003, P05148. Trail at igarapé Tijucaquara, 14–27.XI.2003, P05135, P05194; 15–18.XI.2003, P05035, P05038, P05041; 18–21.XI.2003, P05084 (2 specimens), P05085; 21–24.XI.2003, P05137; 24–27.XI.2003, P05195.

Distribution. Argentina, Brazil.

Figures

FIGURES 6, 7. Dryinus argentinus, Ƥ. 6. Propodeum, dorsal view; 7. Habitus, lateral view.

FIGURES 8, 9. Dryinus argentinus, Ƥ. 8. Head, anterior view; 9. Habitus, dorsal view.

FIGURES 19 – 21. Dryinus striatus, Ƥ. 19. Habitus, dorsal view; 20. Head, anterior view; 21. Propodeum, dorsal view.