Synonyms and other taxonomic changes
Santos & Aguiar (2013) consider M. rufiventris to be a junior synonym of M. discoidalis as merely a color variation.
Numbers
3 spp. in our area
(1); 89 spp. worldwide (Santos & Aguiar, 2013)
Identification
Messatoporus is diagnosed by the combination of the following features:
(2)(3)
-apicolateral corners of clypeus projected
-mandible long and tapered, ventral tooth much shorter than dorsal one or indistinct
-transverse sulcus at base of propodeum long and shallow
-anterior margin of propodeum concave
-posterior area of propodeum almost always transversely wrinkled
-first metasomal spiracle placed approximately on midlength
-median dorsal carina of first metasomal segment absent
-ovipositor basally cylindrical, apically depressed, with ventral valve enclosing completely dorsal valve as a sheath
Overview of Species
Species may be separated in photos by the following traits.
(3) Both dorsal and lateral views are often necessary.
M. compressicornis: middle and hind coxae and trochanters marked in only black and white, lacking orange; flagellomeres laterally compressed
M. discoidalis: middle and hind coxae marked with orange; spot on mesoscutum usually with white lines extending along the notauli; proximal end of tibia with base uniform in color; abdomen with narrower and sharper white-black banding
M. rufiventris: middle and hind coxae marked with orange; spot on mesoscutum subcircular without lines extending; proximal end of tibia with subbasal area lighter than basal 0.08±; abdomen with wider, fulvous-fuscous banding
Life Cycle
Species of the genus are apparently parasitoids of mud nesting wasps in Crabronidae, Pompilidae, and Eumeninae, but host records are available only for three Nearctic species
(2)