Strumigenys hirsuta

Strumigenys hirsuta appears to be widespread in Hong Kong and has been collected from multiple locations in Hong Kong Island, the New Territories, and Lantau Island. Considering the widespread distribution of this species in Hong Kong and its association with disturbed secondary forests or forest remnants, we hypothesize that the geographic range of this species might extend further. It seems likely that this species also occurs in Guangdong province (China). The known elevation range is from 1 to 459 m.

Identification
Dorsolateral margin of head in full-face view with at most 4 freely laterally projecting flagellate hairs: 1 on the upper scrobe margin posterior to the level of eye, 1 at apicoscrobal position, 0–2 posterior to this on the lateral margin of occipital lobe. Cephalic dorsum, dorsal mesosoma and side of pronotum densely and strongly reticulate-punctate; metapleuron and side of propodeum reticulate-punctate but weaker and fainter than on the dorsum; katepisternum mostly smooth and shining. Dorsal and ventral surfaces of femur with numerous fine erect to suberect hairs. SI 61–63.

Strumigenys hirsuta is a member of the caniophanes-complex in the S. caniophanes-group and shares all the characters (Bolton 2000). There are six other species (Strumigenys dipsas, Strumigenys paraposta, Strumigenys lacunosa, Strumigenys benulia, Strumigenys daithma, and Strumigenys pliocera) from the species group that also have unsculptured (or at least not completely sculptured) katepisternum as in S. hirsuta. In comparison, S. dipsas and S. paraposta both have reticulate-rugulose sculpture with fine punctulate on the cephalic dorsum, and predominant longitudinal rugulose sculpture on the pronotal dorsum (instead of simply predominant reticulate-punctate on both cephalic and pronotal dorsum as in S. hirsuta); S. lacunosa, S. benulia, and S. daithma have their entire pleurae and side of propodeum mostly smooth (instead of katepisternum only); S. pliocera has no erect hairs on the dorsal surface of its hind femur, unlike S. hirsuta.

Strumigenys hirsuta (HL 0.71–0.74, HW 0.53–0.55, ML 0.74–0.78) is a smaller species than S. dipsas (HL 0.80–0.86, ML 0.87–0.90) and S. pliocera (HL 0.89, ML 0.90); and a larger species than S. benulia (HL 0.56, HW 0.39, ML 0.56). Strumigenys hirsuta (SI 63–65) also has a markedly relatively shorter scape than those 6 species from the caniophanes-complex: S. benulia (SI 72), S. dipsas (SI 73–76), S. paraposta (SI 73–78), S. lacunosa (SI 75), S. daithma (SI 85), and S. pliocera (SI 84).

Distribution based on Regional Taxon Lists
Palaearctic Region: China.

Nomenclature

 *  hirsuta. Strumigenys hirsuta Tang, Pierce & Guénard, 2019: 18, figs. 6A-C, 7A-C (w.q.) CHINA.

Type Material

 * Holotype worker: Hong Kong, Hong Kong Island, Lung Fu Shan, 22.27899N, 114.13717E, 211 m, 18 November 2014 (M. Wong) (collection code F2W-m2) [IBBL, ANTWEB1009855].
 * Paratype workers (n = 5): same data as holotype worker.
 * Paratype (not holotype) queen: same data as holotype worker.