Chaenusa Haliday, 1839

Godfray, Charles J. & Achterberg, Cornelis Van, 2024, Annotated Checklist of the European Dacnusini and the Dapsilarthra genus group of the Alysiini (Hymenoptera: Braconidae, Alysiinae), Zootaxa 5513 (1), pp. 1-73 : 9

Chaenusa Haliday, 1839

Type species: conjungens Nees

CHOREBIDEA Viereck, 1914 (type species: nereidum Haliday )

CHOREBIDEA Nixon, 1943 (type species: naiadum Haliday )

CHOREBIDELLA Riegel, 1947 (type species: bergi Riegel )

Literature: Griffiths I-859 and see below.

Hosts: Hypothesis —Parasitoids of Hydrellia (= Hydropota ) spp. ( Ephydridae ) mining the leaves of aquatic plants, particularly Potamogeton spp. ( Potamogetonaceae ), and plants growing in wet places. Evidence — See below for European data; Kula et al. (references below); Taxapad. Comment —The most extensive European rearing studies to date are by Burghele (1959; 1960b) who in winter mass-extracted puparia of Hydrellia from ponds in Romania; she records all hosts as H. griseola but Griffiths suggests more species may be present.

Notes: No recent revision of this genus in Europe; for work in North America see Kula and Harms (2016); Kula et al. (2009); Kula and Zolnerowich (2008); Kula et al. (2006) who stress extent of intraspecific morphological variation. Keys to some species can be found in Marshall (1897), Burghele (1960b), Tobias (1986) & Docavo et al. (2006). 15 species listed here but two ( limoniadum and lymphata ) have not been recognised since the 19 th century. 36 species in Taxapad from throughout the world.

conjungens (Nees, 1811; Bracon )

Synonymy: conjugens misspelling; thomsoni (Roman, 1917, Gyrocampa ), Griffiths III-930.

Hosts: Hypothesis —Parasitoid of Hydrellia spp. ( Ephydridae ) mining the leaves of Potamogeton spp. ( Potamogetonaceae ) & Poaceae . Evidence — Burghele (1959; 1960b) (>100); NMS (8). Comment — Recorded hosts H. griseola , H. maura .

DNA Barcode: Yes.

Similar species: C. elongata , C. orghidani .

Notes: The commonest species in the genus. Stelfox (1957) commented on the wide range of antennal segment numbers in C. conjungens and speculated several species may be involved.

dolsi ( Docavo, 1965; Chorebidea )

Literature: Docavo (1965), Docavo et al. (2006).

Similar species: C. naiadum .

Notes: Adults caught on leaves of Potamogeton spp. ( Potamogetonaceae ).

elongata Stelfox, 1957

Literature: Stelfox (1957).

Similar species: C. conjungens .

Notes: Collected from pond margin; female abdomen laterally flattened.

kryzhanovskii Tobias & Perepetchajenko, 1992

Literature: Tobias and Perepechayenko (1992).

Similar species: C. motasi .

limoniadum (Marshall, 1896; Chorebus )

Similar species: C. nereidum .

Notes: Transferred from Chorebus by Perepechayenko (2000b). Poorly known species, little recognised since 19 th century.

llopisi Docavo, 1962

Literature: Docavo (1962), Docavo et al. (2006).

Similar species: C. conjungens .

lymphata (Haliday, 1839; Alysia )

Similar species: C. naiadum .

Notes: Transferred from Chorebus by van Achterberg (1997). Not recognised since 19 th century.