Little is known about the very rare O. simillimus. See Odynerus spinipes for literature on this species.

Identification keys, distribution and general biology are given in Nielsen (1932), Spradbery (1973), Richards (1980), Falk (1991), and Yeo and Corbet (1995).

See Symmorphus crassicornis for literature on this species.

A small black solitary wasp. Identification keys are given in Yeo & Corbet (1995), Lomholdt (1984) and Richards (1980).When using Yeo & Corbet (1995) or Richards (1980), it should be noted that Crossocerus congener (Dahlbom) has recently been added to the British species list. C. congener is very similar in appearance to C. podagricus but has only been recorded on a very few occasions. Critical determinations for C. podagricus are best made using Lomholdt (1984). 

Formerly known as C. pusillus. A small black solitary wasp. Identification keys are given in Yeo & Corbet (1995), Lomholdt (1984) and Richards (1980).

A small black solitary wasp. Identification keys are given in Yeo & Corbet (1995), Lomholdt (1984) and Richards (1980).

A small black solitary wasp with a yellow clypeus in both sexes. Identification keys are given in Yeo & Corbet (1995), Lomholdt (1984) and Richards (1980).

Considerable disagreement exists regarding the definition of this name. Linsenmaier (1997), Kunz (1994) and Morgan (1984) all treat it differently. Here it is meant in the sense given by Morgan (1984). See Archer (2003) for discussion of this problem.

Identification keys and hosts are given in Morgan (1984) and Archer (2003). Kunz (1994) treats C. rutiliventris as a synonym of C. ignita. Linsenmaier (1997) treats this taxon as a valid species including a subspecies vanlithi Linsenmaier, 1959.

Identification keys and biology are given in Morgan (1984) and Archer (2003). Kunz (1994) treats C. schencki as a synonym of C. ignita, while Linsenmaier (1997) treats this taxon as a subspecies of C. ignita.