Key to Temnothorax andersoni species group workers

This worker key is based on: Mackay, W. P. 2000. A review of the New World ants of the subgenus Myrafant, (genus Leptothorax) (Hymenoptera: Formicidae). Sociobiology. 36:265-444.

This complex is closely related to the tricarinatus species complex, which has 3 major carinae on the clypeus, including a sharp, well-defined medial carina and two lateral carinae, which converge anteriorly. Some tricarinatus complex species that can be confused with this complex are included in the following key (T. carinatus, T. cokendolpheri, T. gallae and T. rugulosus).

1

Dark brown or bicolored; propodeal spines moderately well developed, or very well developed . . . . . 2

Pale yellow or light brown; propodeal armature consisting of small angles or spines (Fig. 13) . . . . . 4

2

return to couplet #1

Entire dorsal surface of head with striae; California . . . . . 3

Dorsum of head mostly smooth and shining; southern Mexico (Chiapas) . . . . . Temnothorax bicolor

3

return to couplet #2

Node of petiole rounded; nests in soil . . . . . Temnothorax lindae = Temnothorax nevadensis

Node of petiole relatively sharp; nests in plant cavities . . . . . Temnothorax gallae

4

return to couplet #1

Eyes large, greatest diameter longer than length from base of mandible to anterior border of eye . . . . . 5

Eyes smaller, greatest diameter less than or equal to length from base of mandible to anterior border of eye . . . . . 6

5

return to couplet #4

Nearly white in color; dorsum of pronotum with fine rugulae . . . . . Temnothorax liebi

Light brown; dorsum of pronotum with distinct rugae . . . . . Temnothorax bestelmeyeri

6

return to couplet #4

Eye tiny, maximum diameter ½ length of distanct between base of mandible and anterior edge of eye; head at least partially smooth and shining . . . . . Temnothorax ocellatus = Temnothorax andrei

Eye larger, maximum diameter nearly as long as distance between base of mandible and anterior border of eye, if eyes smaller, dorsum of head densely punctate . . . . . 7

7

return to couplet #6

Dorsum of base of first gastral tergite finely punctate . . . . . Temnothorax andersoni

Dorsum of first gastral tergite completely smooth and polished . . . . . 8

8

return to couplet #7

Entire dorsum of head densely and evenly punctate . . . . . Temnothorax punctatissimus

Part of head smooth and shining, or at least head not densely and evenly punctate . . . . . 9

9

return to couplet #8

Head with fine rugae; Michoacan . . . . . Temnothorax rugulosus +

Head with striae, moderately smooth and polished; western United States and northern Mexico (Chihuahua) . . . . . 10

10

return to couplet #9

Eyes with 7-8 ommatidiain maximum diameter; dorsum of head mostly smooth and glossy, but with very fine costulae . . . . . Temnothorax cokendolpheri +

Eyes with 8-9 ommatidia in maximum diameter; dorsum of head with costulae, little of dorsum smooth and shining . . . . . Temnothorax carinatus +

+ member of tricarirtahrs species complex