Key to Crematogaster degeeri species assemblage queens

This key to queens is based on: Blaimer, B.B. & Fisher, B.L. 2013. Taxonomy of the Crematogaster degeeri-species-assemblage in the Malagasy region (Hymenoptera: Formicidae). European Journal of Taxonomy 51: 1-64 (DOI 10.5852/ejt.2013.51).

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1

 * Small queens (HW < 1.30, WL < 2.20) . . . . . 2


 * Large queens (HW > 1.30, WL > 2.20) . . . . . 5

2
return to couplet #1
 * Head shape variable, but usually elongate, appearing longer than wide (CI 0.94-1.03); eyes smaller (OI < 0.32), situated below midline of head in full-face view; antennal scapes shorter, often not surpassing level of lateral ocelli (SI < 0.67) . . . . . 3


 * Head shape square, appearing as wide as long (CI 1.06); eyes larger (OI > 0.33), situated at midline of head in full-face view; antennal scapes longer, surpassing level of lateral ocelli (SI > 0.68) . . . . . Crematogaster sewellii

3
return to couplet #2
 * Body color brown . . . . . 4


 * Body color yellow . . . . . Crematogaster maina

4
return to couplet #3
 * Very small species (HW 1.01, WL 1.68); head sculpture finely reticulate; ocelli small and protruding very little from head surface . . . . . Crematogaster alafara


 * Larger species (HW 1.13-1.41, WL 1.73-2.43); head sculpture aciculate-shiny; ocelli distinctly protruding from head surface . . . . . Crematogaster dentata (in part - also )

5
return to couplet #1
 * Antennal scapes long, surpassing lateral ocelli easily and almost reaching head margin (SI > 0.76); body color yellow . . . . . Crematogaster bara


 * Antennal scapes shorter (SI < 0.74); body color other than yellow . . . . . 6

6
return to couplet #5
 * Eyes small (OI 0.23-0.26); antennal scapes very short (SI 0.57-0.59); large queens (HW 1.70-2.18, WL 2.56-3.44); color black . . . . . Crematogaster mafybe


 * Eyes usually larger (OI 0.25-0.33); antennal scapes mostly longer (SI 0.57- 0.74); usually smaller queens (HW 1.30-1.77, WL 2.20-2.69); color variable, usually not black . . . . . 7

7
return to couplet #6
 * Head distinctly wider than long (CI 1.14-1.21); tricolored: reddish-orange, yellow and black; or at least abdominal segment 4 dorsally with a yellowish patch . . . . . Crematogaster tricolor


 * Head shape variable, but usually not much wider than long (CI < 1.10); uniformly colored . . . . . 8

8
return to couplet #7
 * Eyes situated at about midline of head in full-face view; antennal scapes longer (SI 0.68-0.72), surpassing level of lateral ocelli . . . . . Crematogaster degeeri


 * Eyes situated below midline of head in full-face view; antennal scapes shorter (SI 0.57-0.67), not surpassing level of lateral ocelli . . . . . Crematogaster dentata (in part - also )