Key to the species of Macrotera subgenus Macroterella
Macroterella Male Key:
1. More light colored, lower half of face strongly yellow, pronotal tubercles yellow, scutellum and propodeum often yellow; frons covered in very dense punctures; stigma small and dark....M mellea
Darker species, lower half of face often with maculations, but never strongly yellow; pronotal tubercles dark; frons at most sparsely punctured, stigma medium and clearish.....2
2. Face not entirely light below level of atennae, at least supraclypeal and subantennal areas dark; T7 only weakly folded over laterally....3
Face entirely light below level of antennae; T7 strongly folded over, sides meeting or almost meeting, making a keel shape......4
3. Forelegs dark; face marks white; S1 lacking median protrusion.....M nigrella
Forelegs light anteriorly; face marks yellowish; S1 with a strong, pointed medial protrusion on apical margin of S1.....M. tristella
4. T7 with two lateral prongs; S1 with a weak median protrusion on the apical margin of S1 (often hard to see).....M opacella
T7 lacking lateral prongs, S1 unmodified.....5
5. Lateral margins of T7 meeting apically, creating a longitudinal carina.....M. carinata
Lateral margins of T7 not meeting apically.....M. mortuaria
Macroterella Female Key
1. Yellow and black on face and thorax; abdomen orange; stima small and dark; Chaemysyce specialist.....M. mellea
Lacking yellow maculations; abdomen brown or black; stigma medium-sized and clear, at least medially.....2
2. Fore-legs dark; thorax with a combination of very sparse thick hairs and minute recumbent hairs (hairs are often worn off in older specimens).....3
Fore-legs with a distinct light stripe anteriorly; thorax with only extremely minute short hairs....4
3. Posterior margin of hind-tibia narrowed just before apex; frons black with metallic blue tints; clypeus less protruberant with sides more converging.....M. tristella
Hind-tibia with a continuous margin; frons black, lacking metallic tints; clypeus more protruberant with sides more parallel....M. nigrella
4. Eyes slightly converging below....M. mortuaria
Eyes parallel......5
5. Frons with metallic blue or green tints; fovea small, length about 3X width.....M. opacella
Frons black, lacking metallic tints; fovea larger and longer, length about 4X width.....M. carinata
Macroterella Male Key:
1. More light colored, lower half of face strongly yellow, pronotal tubercles yellow, scutellum and propodeum often yellow; frons covered in very dense punctures; stigma small and dark....M mellea
Darker species, lower half of face often with maculations, but never strongly yellow; pronotal tubercles dark; frons at most sparsely punctured, stigma medium and clearish.....2
2. Face not entirely light below level of atennae, at least supraclypeal and subantennal areas dark; T7 only weakly folded over laterally....3
Face entirely light below level of antennae; T7 strongly folded over, sides meeting or almost meeting, making a keel shape......4
3. Forelegs dark; face marks white; S1 lacking median protrusion.....M nigrella
Forelegs light anteriorly; face marks yellowish; S1 with a strong, pointed medial protrusion on apical margin of S1.....M. tristella
4. T7 with two lateral prongs; S1 with a weak median protrusion on the apical margin of S1 (often hard to see).....M opacella
T7 lacking lateral prongs, S1 unmodified.....5
5. Lateral margins of T7 meeting apically, creating a longitudinal carina.....M. carinata
Lateral margins of T7 not meeting apically.....M. mortuaria
Macroterella Female Key
1. Yellow and black on face and thorax; abdomen orange; stima small and dark; Chaemysyce specialist.....M. mellea
Lacking yellow maculations; abdomen brown or black; stigma medium-sized and clear, at least medially.....2
2. Fore-legs dark; thorax with a combination of very sparse thick hairs and minute recumbent hairs (hairs are often worn off in older specimens).....3
Fore-legs with a distinct light stripe anteriorly; thorax with only extremely minute short hairs....4
3. Posterior margin of hind-tibia narrowed just before apex; frons black with metallic blue tints; clypeus less protruberant with sides more converging.....M. tristella
Hind-tibia with a continuous margin; frons black, lacking metallic tints; clypeus more protruberant with sides more parallel....M. nigrella
4. Eyes slightly converging below....M. mortuaria
Eyes parallel......5
5. Frons with metallic blue or green tints; fovea small, length about 3X width.....M. opacella
Frons black, lacking metallic tints; fovea larger and longer, length about 4X width.....M. carinata