Key to the Neotropical Xanthopimpla (modified from Townes |969)

1 Propodeum with only posterior transverse carina present; metasoma entirely yellow ............................................................................ X. peruana Krieger

– Propodeum with both posterior transverse and anterior transverse carinae present (Figs 2, 6); metasoma usually with brown or black markings .......... 2

2 Dorsal part of occipital carina lacking; ovipositor sheath usually relatively long, 1.0-1.1 as long as hind tibia*.................................... X. aurita Krieger

– Dorsal part of occipital carina present, from weak to very strong (Figs 4, 8); ovipositor sheath less than 0.9 as long as hind tibia..................................... 3

3 Dorsal part of occipital carina very strong, forming vertical flange (Figs 4, 8); mesosternum black (Figs 1, 5) .................................................................... 4

– Dorsal part of occipital carina weak and low; mesosternum yellow ............. 5

* Gauld (1991) noted that some X. aurita specimens may have a shorter ovipositor (0.8-0.9 as long as hind tibia). According to Gauld the range 0.8-1.1 may not be continuous but bimodal.

4 Central part of posterior transverse carina horizontal (Fig. 6); propodeum with lateral longitudinal carina present, defining area dentipara (Fig. 6); yellowish species with wide black markings on occipital area (Fig. 8); vertical black stripe on posterior part of mesopleuron ...................... X. jussilai sp.n.

– Central part of posterior transverse carina bowed (Fig. 2); lateral longitudinal carina absent, not defining area dentipara (Figs 2, 3); bright yellow species with small black markings on occipital area, vertical black stripes on anterior and posterior part of mesopleuron (Fig. 1)..................... X. amazonica sp.n.

5 Lateral longitudinal carina of propodeum absent, not defining area dentipara; hind femur with a brown stripe on front side.......... X. rhabdomera Townes

– Lateral longitudinal carina of propodeum present, at least partly defining area dentipara; hind femur lacking a brown stripe on front side ......................... 6

6 Area superomedia separated from area dentipara by complete or subcomplete carina; trochanter and nearly always also coxa of hind leg with black markings....................................................................... X. craspedoptera Krieger

– Area superomedia not separated from area dentipara; trochanter and coxa of hind leg entirely yellow............................................... X. spiloptera Krieger