Axima Walker, 1862

Arias-Penna, Diana Carolina, Pape, Thomas & Krogmann, Lars, 2014, Stalk-eyed wasps-review of a largely unnoticed group of morphologically bizarre chalcidoid wasps (Hymenoptera: Eurytomidae: Axima), Zootaxa 3866 (4), pp. 583-590 : 584

Axima Walker, 1862

Axima Walker, 1862: 373 . Type species, Axima spinifrons Walker, 1862 , by monotypy.

Aplatoides Yoshimoto & Gibson, 1979: 421 . Type species, Aplatoides diabolus Yoshimoto & Gibson, 1979 , by original designation. [Synonymy by Lotfalizadeh et al. (2007).]

Diagnosis. Head distinctly broader than mesosoma and with small denticle or large projection on vertex laterally between scrobal depression and eye. Eye protruding, sometimes situated on tubular process. Face with interantennal region distinctly truncate. Anterior ocellus above scrobal depression. Gena carinate laterally. Anterior margin of pronotum carinate laterally; dorsomedially rounded with raised sculpture close to anterior pronotal margin, sometimes forming distinct spine. Dorsal surface of propodeum lying at approximately 45° angle with longitudinal axis of thorax. Propodeum extending beyond bases of metacoxae. Metasoma with long, slender petiole, and with compressed, smooth, lanceolate gaster having Mt2–Mt4 reduced and often patches of white setae on remaining terga ( Walker 1862, Burks 1971, DiGiulio 1997).

Comments. Eight species of Axima are known, including the new species described herein, which are restricted to the New World ( Table 1 ). Only three of these are characterized by stalked eyes, a unique morphological modification that led Yoshimoto & Gibson to establish a separate genus for A. diabolus . Lotfalizadeh et al. (2007) recognized A. diabolus as a derived species within Axima and synonymized the name Aplatoides under Axima . So far no male stalk-eyed wasps have been found. Based on the results of a phylogenetic analysis of morphological characters, Lotfalizadeh et al. (2007) proposed seven autapomorphies of Axima : (1) head transverse in frontal view, with protruding eyes; (2) lateral foraminal plate completely delimited laterally; (3) postgenal bridge without median stripe of ornamentation, and only a few digitiform expansions visible; (4) propodeum with elongate nucha; (5) metapleuron with ventral shelf very long; (6) petiole elongate and bent downwards posteriorly; and (7) Mt5 long. Initially, Axima was placed in the subfamily Aximinae , but this is now considered a synonym of Eurytominae ( Stage & Snelling 1986) . Currently, A. zabriskiei Howard is the only species for which biological information is associated. This species has been reared as solitary or gregarious ectoparasitoids of dwarf carpenter bees of the genus Ceratina Latreille , subgenus Zadontomerus Ashmead ( Apidae : Xylocopinae ) ( Howard 1890, Rau 1928, Krombein 1960, Peck 1963, Burks 1966, Kislow 1976). The larval development was studied by Burks (1966).

The morphological distinctiveness of stalk-eyed wasps led us to treat them here in an informal species group within Axima , i.e., the noyesi species group (= Aplatoides , see Yoshimoto & Gibson 1979 for an extensive diagnosis) and treat the remaining species in the spinifrons species group.