A new species of Oomyzus Rondani (Hymenoptera, Eulophidae) and first record of O. gallerucae (Fonscolombe) from China, with a key to Chinese species

Abstract Oomyzus flavotibialissp. nov. is described from Liaoning and Shandong provinces, China. Oomyzus gallerucae (Fonscolombe) is reported for the first time from China. A key to Chinese species of Oomyzus is provided.

Oomyzus can be recognized by the following combination of characteristics (Graham 1991;LaSalle 1994): female antenna usually with funicle segments not or slightly longer than wide (rarely funicle segments relatively longer); mesoscutum with 2-5 adnotaular setae on each side; submedian grooves usually weak or absent, rarely strong; propodeum with or without paraspiracular carinae (but not as in Tetrastichus); mesoand metabasitarsus often shorter than second tarsomere; forewing with one rarely two, dorsal seta on submarginal vein; metasoma subcircular to ovate, from shorter than mesosoma to about as long as head and mesosoma combined.
In the present paper, a new species of Oomyzus from China is described, O. gallerucae is newly reported from China, and a key to Chinese species is provided.

Materials and methods
Specimens were collected by sweep net and most were dissected and mounted dorsally in Canada balsam on steps following the method of Noyes (1982). Photographs were taken with a digital CCD camera attached to an Olympus BX51 compound microscope, and most measurements were made from slide-mounted specimens using an eye-piece reticle with an Olympus CX21 microscope. Terminology follows the Hymenoptera Anatomy Consortium (2019), and the following abbreviations are used: F1-4 (flagellomeres 1-4), POL (minimum distance between lateral ocelli), OOL (minimum distance between lateral ocellus and eye margin), OD (longest diameter of a lateral ocellus), MV (marginal vein), STV (stigmal vein), SMV (submarginal vein). All the specimens listed below are deposited in Northeast Forestry University, Harbin (NEFU), China.
Key to species of Oomyzus Rondani from China. Females.

1
Mid lobe of mesoscutum without median line (Fig. 3) Diagnosis. Female. Body black with all tibiae yellow; propodeum with median carina poorly defined, spiracle circular, partly exposed, and separated by about its diameter from metanotum; propodeum reticulation absent; MV 2.1-2.6× as long as STV; SMV with two dorsal setae. Male. Antenna with plaque 0.67× as long as scape. Forewing with costal cell 1.4× as long as MV, MV 2.5× as long as STV, SMV with two dorsal setae.
The new species belongs to the incertus-group (Graham 1991). Among the species recorded from China, O. flavotibialis is similar to O. scaposus, but can be separated from the latter by the following combination of characteristics: propodeum with median carina poorly defined, (vs sharply defined), spiracle circular, partly exposed (vs suboval, fully exposed) and separated by about its diameter from metanotum (vs about 0.5× its diameter ); propodeum reticulation absent (vs present but very fine); MV 2.1-2.6× as long as STV (vs 3.0-3.7×); SMV with two dorsal setae (vs usually with only one); tibiae completely yellow (vs mainly brown to blackish). The new species is also similar to the extralimital species O. incertus (see Graham 1991 for description), but can be separated from the latter by characteristics: POL 2.1-2.5× OOL (vs 1.5-1.65×), OOL 1.5-1.8× OD (vs 2.3-2.5×); propodeum medially distinctly longer than dorsellum (vs hardly longer than).
Male. Similar to female. Antenna (Fig. 7) with scape robust, shorter than an eye, 2.62× as long as broad; plaque 0.67× as long as scape; pedicel 1.71× as long as broad; F1 quadrate, shorter than other funicular segments, F2-F4 similar in shape, 1.40× as long as broad; clava broader than funicle, 2.74× as long as broad. Forewing (Fig. 8 Diagnosis. Female. Head ( Fig. 9) with POL about 2× OOL. Antenna ( Fig. 10) with funicle segments quadrate or only very slightly longer than wide; clava as long as funicle, 2.7× as long as broad. Mesosoma (Fig. 11) 1.20-1.25× as long as broad. Mesoscutum midlobe with three adnotaular setae on each side in one row, median line present. Propodeum medially as long as or slightly shorter than dorsellum, median carina raised, narrower in front but broadening posteriorly. Forewing (Fig. 12) costal cell as long as or slightly longer than MV; SMV with one dorsal seta; MV 2.8-3.2× STV.

Male. Unknown for Chinese material.
Comments. Our specimens agree well with the description by Graham (1985). For a redescription and taxonomic history, see Graham (1985).