Ypsilonigaster Fernandez-Triana gen. n.

Type species.

Ypsilonigaster tiger Fernandez-Triana & Boudreault, here designated.

Diagnostic description.

Face with strong sulcus medially near antennal base. Scutellar disc flat, entirely smooth, and shiny (Figs 41D, 43E, 44C, E, 45G). Propodeum mostly smooth but with strong median carina (Figs 41D, 43E, 44E). Fore wing with small, slit-shaped areolet. Metatibia with short, stout spines dorsally. T1 divided in three areas by a strong sulcus shaped as an inverted “Y” (Figs 40B, 41E, F, 42A, 43D, E, 44B-C, E, 45D, H). Hypopygium unfolded and inflexible (Figs 41A, 42C, 44A). Ovipositor relatively strongly curved downwards (Figs 41A, 42C, 44A). Ovipositor sheaths thoroughly covered by setae (Fig. 44A).

Putative autapomorphies and potentially related genera.

Ypsilonigaster has T1 divided in three areas by a strong sulcus shaped as an inverted “Y”, a unique feature within Microgastrinae . Ypsilonigaster seems to be related to other Old World genera with strong median carina on propodeum, fore wing areolet, and relatively long ovipositor sheaths (e.g., Choeras s.l., see Discussion below), but differs from most of those genera by having an unfolded and inflexible hypopygium.

Biology.

Host unknown.

Distribution.

All known species are found in the Old World tropics (Afrotropical and Oriental regions).

Molecular data.

Two DNA barcodes are available, both very distant from any other Microgastrinae sequence available in BOLD (8-10% of base pair differences). However, those two sequences (which were obtained from two different species and belong to BINs BOLD:AAV2124 and BOLD:ABY3660) which are also very different from each other and cluster very separate (based on a Neighbor Joining tree built with 35,000+ Microgastrinae sequences available in BOLD as of January 2018).

Etymology.

From “Ypsilon” (in several languages an alternative form or synonym of the ancient Greek letter “Upsilon”, which is depicted as a “Y”) and “gaster” (in Greek “stomach” or “abdomen”, also used for the metasoma in Hymenoptera), referring to the Y-shaped sulcus in the first tergite of metasoma that characterizes this genus. The gender of the genus is neuter.

Species.

We recognize at least six different species, four of them new and described below. They can be separate using the following key.