Temnothorax rudis

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Biology
Ward 2005:19-20 NEEDS EDITING Comments. This is a distinct species that occurs sympatrically with T. nevadensis in many parts of northern and central California, without showing any sign of intergradation. T. rudis is readily distinguished from T. nevadensis by petiole shape. In T. rudis the petiole is broader in profile, with the anterior and posterodorsal faces meeting at approximately 90º, and the posterodorsal face declining gently (Fig. 10). In T. nevadensis the petiole is more slender in profile, with the anterior and posterodorsal faces forming an acute angle (Fig. 9). In addition T. rudis has coarser body sculpture and is lighter in color than T. nevadensis. T. rudis is common in mixed coniferous forests of California, up to about 1750m elevation. Colonies can be found in rotten wood, under stones, in fallen acorns, and in the leaf litter. Bolton (1995) stated that rudis Wheeler 1917a, then combined with Leptothorax, was a primary junior homonym of rudis Mayr 1868c. Mayr’s species, a fossil taxon, was originally combined with Macromischa, however, and then later with Nothomyrmica (Wheeler 1915i), prior to Macromischa being subsumed under Leptothorax. Mayr’s rudis was never treated as a species of Leptothorax, so no homonymy arises.

Original Combination
Leptothorax nevadensis subsp. rudis Wheeler, W.M. 1917a: 508 (w.q.) U.S.A. Combination in Temnothorax: Ward, 2005: 19. Junior synonym of nevadensis: MacKay, 2000: 376. Revived from synomymy and raised to species: Ward, 2005: 19.

Worker
Worker. Length 2.6-3.3 mm. Distinctly larger and more robust than the typical nevadensis and much more coarsely sculptured. Funicular joints 2-8 distinctly broader in proportion to their length. Head subopaque, finely and densely longitudinally rugose, with punctate interrugal spaces and sometimes with an interrupted shining median line. Frontal area shining; very finely striated. Mandibles coarsely punctate, striated at their bases. Thorax and petiole coarsely punctate-rugose, the rugae on the pleurae and often also on the pro- and epinotum longitudinal, on the mesonotum often vermiculate. Declivity of epinotum densely punctate and as opaque as the remainder of the thorax (more shining in the typical form). Postpetiole densely punctate and opaque. The epinotal spines are much stouter and blunter, and the petiolar node is much less compressed anteroposteriorly, its posterior surface being much more convex than in typical nevadensis. The color is considerably darker, the body being castaneous, with the head and gaster, except its incisures, blackish, the mandibles, clypeus, antennae and legs yellowish brown, the femora infuscated in the middle. Pilosity as in the typical form.

Queen
Smaller than the female of typical nevadensis, with longer and more slender epinotal spines and the funicular joints 2-8 shorter. Sculpture of the head, thorax and petiole a little coarser. Petiolar node like that of the worker. In the typical form it is much compressed anteroposteriorly and has a sharp, transverse superior border. There is very little difference in color between the two forms.

Type Material
Presumably MCZ and USNM.

Type Locality
Described from numerous workers and a single female taken from small colonies nesting under the edges of stones in Tenaya Canyon, Yosemite Valley, Cala.