Temnothorax spinosior

Terayama and Onoyama (1999) - T. spinosior is found in dry open areas, such as grasslands and bare places. It nests in the soil. A queen body size dimorphism is known (Hamaguchi & Kinomura, 1996). Most larger queens are found in monogynous colonies while most smaller queens are found in polygynous colonies. Workers are found on the ground, seldom on trees. Nuptial flights occur in July (Sonobe, 1980). The chromosome number is 2n = 24 (Imai & Yosida, 1965).

Identification
T. spinosior most resembles Temnothorax eburneipes with notes about the distinctions between these two species noted under the latter.

Terayama and Onoyama (1999) - Total length of workers around 2 mm. Body color black to blackish brown. Scapes almost reaching posterior margin of head in full-face view. Dorsal outline of mesosoma weakly and evenly convex in profile. Metanotal groove incised dorsally. Propodeal. spines long, acute and narrow somewhat downcurved. Petiolar node in profile triangular (in some specimens dorsum narrowly convex and not angulate), with weakly convex posterior margin (almost straight in some specimens).

Distribution based on Regional Taxon Lists
Palaearctic Region: China, Japan, Republic of Korea.

Nomenclature

 *  spinosior. Leptothorax congruus var. spinosior Forel, 1901e: 371 (w.) JAPAN. Wheeler, W.M. 1906c: 317 (q.); Imai, 1966: 119 (k.). Combination in Temnothorax: Bolton, 2003: 271. Raised to species: Terayama & Satoh, 1990b: 532. See also: Terayama & Onoyama, 1999: 93.

Type Material
Terayama and Onoyama (1999) - Worker. Type locality: Sapporo (Matsumura leg.). [Two syntype workers in examined.]

Determination Clarifications
All the previous records of T. spinosior from Yaku Island (Terayama & Yamane, 1984) were Temnothorax anira, and no reliable record of this species is known from the island.

Radchenko (2004) - Among rich investigated material from North Korea (more than 100 specimens) I did not find T. spinosior, but Temnothorax eburneipes only; records of T. spinosior from South Korea and China need confirmation.