Temnothorax rugatulus

Modified from Mackay (2000) Higher elevation coniferous forest species which occurs in moist habitats, in shaded grassy slopes with pines or grasslands. Temnothorax rugatulus can also be found in pinyon-juniper and cool desert habitats. Nests have been found in the soil, under rocks, in decaying wood, in grasses and in trees. Colonies may be monogynous or polygynous and there are microgyne and macrogyne queen forms.

Identification
Mackay (2000) "Workers of this species have an 11 segmented antenna, a coarsely rugose dorsal surface of the head, the dorsum (and sides to a lesser extent) of the mesosoma and petiole are rugose as the head, the propodeal spines are well developed, longer than the distance between their bases, the dorsum of the postpetiole has rough punctures.

This species can be recognized by the coarse rugae on the head, the areas between the rugae are punctured, but shiny (Fig. 156). This characteristic separates Temnothorax rugatulus from Temnothorax bradleyi and Temnothorax smithi. It is smaller than Temnothorax josephi and is basically concolorous medium yellowish-brown, often with dark infuscation on the head and mesosoma. The node of the petiole is rounded in profile, not truncate as in Temnothorax ambiguus. The subpetiolar process is often about as wide at the tip as it is at the base, although specimens that were previously referred to as Temnothorax rugatulus tend to have a tapered subpetiolar process. The propodeal spines are well developed, which separates it from Temnothorax schaumii, and Temnothorax whitfordi."

Range
USA, CANADA. US - Washington, Oregon, Idaho, Montana, North Dakota, South Dakota, Wyoming, California, Nevada, Utah, Colorado, Arizona, New Mexico, Texas; Canada - British Colombia, Alberta.

Habitat
High elevation coniferous forest, shaded grassy slopes with pines or grasslands, pinyon-juniper and cool desert habitats.

Abundance
Common

Idaho
Cole (1934): This ant is rather frequent in moist habitats near Twin Falls, Hagerman and Buhl, chiefly along the Snake River. Colonies are small, the workers timid and sluggish and the brood scant. Winged forms appear at Twin Falls in late September.

Nevada
Wheeler and Wheeler (1986): In Nevada Temnothorax rugatulus records are widely scattered, but absent from the southern quarter of the state. We have 30 records from 20 localities; 4,700-9,100 ft., mostly 6,000-7,000 ft. Fifteen records were from the Coniferous Forest Biome, 5 from the Pinyon-Juniper Biome, and 4 from the Cool Desert. Five nests were under stones, 8 were in rotten wood. This is a slow-moving ant.

New Mexico
Cole (1953, 1954): Colonies of Temnothorax rugatulus Emery were observed at an elevation of 6,350 ft. at Bandelier National Monument and 5 mi. E. of Taos, 7,350 ft. At both places nests were common beneath stones on shaded grassy slopes with pines. A number of the colonies was very populous and multiple queens were present.

Colony Attributes
Moglich (1978) studying a population of Temnothorax rugatulus in a mixed oak-juniper forest in the Chiricahua Mountains found colonies had an average of 109 workers (range 30 to over 200).

Nesting Biology
Nests have been found in the soil, under and between rocks, in decaying wood, in grasses and in trees.

Moglich (1978) studying a population of Temnothorax rugatulus in a mixed oak-juniper forest in the Chiricahua Mountains described their nests, which were found under stones. Dry brown oak leaves, juniper needles, little twigs and a diversity of other plant materials formed the bases of the nest chambers, which showed flat, often unbroken surfaces. Thus the whole colony was exposed after the stone was turned. The ants were crowded together either on the top of the material or upside down on the stone ceiling. Sometimes, however, a few small chambers were built into the base of the nest. Although the space covered by the rock measured 219 x 292 cm2 (range 32-1 800 cm2) the nest chambers were considerably smaller (24 x 17 cm2; range 2.4-63 cm2). The walls confining the nest chambers were constructed out of fine material like soil and small vegetation particles. Mean nest density was 1.5 ± 0.9 per 9.3 m2).

Nest Migration
Temnothorax rugatulus use both tandem running and carrying behavior during nest emigration. Tandem running is strictly limited to the first phase of nest emigration, whereas carrying behavior is the predominant technique (84 %). Workers which are recruited by tandem running inspect the new nest site. If they accept it, they join the scout force and lead or carry nestmates to the new nest by themselves. (Moglich 1978)

Other Insects
Amecocerus sp. (Coleoptera: Melyridae; det. J.M. Kingsolver) was taken in a nest of Peavine Peak (Washoe Co.) at 6,800 ft. (Wheeler and Wheeler 1986)

Cysticercoids of a dilepidid cestode were found by dissection of aberrant yellowish workers and virgin queens of the ant Leptothorax rugatulus from several mountain ranges in the southwestern United States. The cestode was not positively identified, but cysticercoids are similar to those of the genus Anomotaenia previously found in related ants. (Heinze et al. 1998

Taxonomy
Leptothorax (Leptothorax) rugatulus Emery, 1895c: 321 (w.) U.S.A. Taber & Cokendolpher, 1988: 95 (k.). Combination in L. (Myrafant): Smith, M.R. 1950: 30; in Temnothorax: Bolton, 2003: 272. Subspecies of curvispinosus: Wheeler, W.M. 1903c: 241. Revived status as species: Wheeler, W.M. 1917a: 509. Senior synonym of annectens, cockerelli, mediorufus: Creighton, 1950a: 269; of brunnescens: MacKay, 2000: 394.

Worker
Testacea, capite abdomineque magis minusve (uscatis, capite thoraceque dense punctatis et cum rugis subtilibus longitudinalibus,antennis 11 articulatis, thorace breviusculo, dorso haud impresso, spinis vix curvatis, obliquis, mediocribus, acutis; petioli segmento 1. postice modice incrassato, 2. subtrapezoideo, scapo pedibusque haud pilosis.

Queen
Queens are known for this species but they have not been described.

Male
Males are known for this species but they have not been described.

Type Material
AMNH,MCSN (as reported in Mackay 2000)

Type Locality Information
The original description lists specimens from Colorado and South Dakota. Creighton (1950) gives the type locality as Colorado "by present restriction."

Etymology
Morphology. A reference to the rugosity found on the body.