Strumigenys scylla

Identification
Bolton (2000) - A member of the Strumigenys leptothrix-group. Along with Strumigenys rudinodis, Strumigenys scolopax, Strumigenys megaera and Strumigenys medusa, scylla has a bispinose propodeum and a pair of acute propodeal lobes at the base of the declivity, the two being linked only by a pair of narrow carinae that run down the sides of the declivity. Of these five species scylla and medusa together have long fine hairs that project freely from the tibiae and numerous long fine acute hairs, some or all of which are curved anteriorly, projecting from the dorsolateral margins of the head from the level of the eyes to the apices of the occipital lobes. S. scylla and medusa are separated by the following characters.

S. scylla: Mandibles and scapes relatively shorter: MI 14, SI 81-84. Eye larger, 0.18-0.20 X HW and with 6-7 ommatidia in the longest row. Longest hairs on vertex strongly arched anteriorly. Propodeal lobes broadly triangular, less than half the length of the propodeal spines.

S. medusa: Mandibles and scapes relatively longer: MI 16-18, SI 87-94. Eye smaller, 0.14-0.15 X HW and with 4 ommatidia in the longest row. Longest hairs on vertex approximately vertical, not strongly arched anteriorly. Propodeal lobes narrowly triangular, more than half the length of the propodeal spines.

Distribution based on Regional Taxon Lists
Indo-Australian Region: New Guinea, Philippines.

Nomenclature

 *  scylla. Pyramica scylla Bolton, 2000: 439 (w.q.) NEW GUINEA. Combination in Strumigenys: Baroni Urbani & De Andrade, 2007: 127

Worker
Holotype. TL 2.9, HL 0.73, HW 0.50, CI 68, ML 0.10, MI 14, SL 0.42, SI 84, PW 0.34, AL 0.84. With head in full-face view the dorsolateral margin, from level of eye to occipital corner, with numerous (more than 1 0 on each side) long to very long fine projecting hairs that curve anteriorly and are acute apically. In profile the cephalic dorsum, from about the highest point of the vertex to the occipital margin, with abundant long fine hairs that are curved forward and are acute apically; dorsal head in front of this level without long hairs. Eye with 6 ommatidia in the longest row. Leading edge of scape with a row short decumbent hairs that are directed toward the apex of the scape; without freely projecting hairs of any form. Vertex predominantly reticulate-punctate but dorsum of occipital lobes and vertex immediately in front of occipital margin with scattered longitudinal rugulae. Dentition discussed in introduction to group. Pronotum marginate dorsolaterally, the dorsum longitudinally costulate-rugulose and the spaces between this sculpture weakly reticulate-punctate. Dorsal surfaces of alitrunk, waist and first gastral tergite with numerous long to very long fine soft hairs that are curved or flexuous and acute apically. Dorsal (outer) surfaces of middle and hind tibiae with freely projecting long fine suberect to subdecumbent hairs, the longest of which distinctly exceed the maximum width of the segment from which they arise. Similar long hairs also project from all other leg segments. Propodeum armed with a pair of long narrow straight spines, base of declivity with a pair of broadly triangular propodeal lobes that are acute apically; the declivity between these margined only by a fine carina. Spongiform appendages of waist segments in profile well developed. Lateral lobe of petiole small, not extending forward alongside of node. In dorsal view postpetiole disc margined by spongiform tissue on all sides, the disc with some fine longitudinal rugulae and superficial punctulation.

Paratypes. TL 2.9-3.0, HL 0.72-0.76, HW 0.51-0.53, CI 70-71, ML 0.10-0.11, MI 14, SL 0.42-0.43, SI 81-82, PW 0.36-0.37, AL 0.85-0.90 (2 measured). As holotype but eye may have 6 or 7 ommatidia in the longest row.

Type Material
Holotype worker, Papua New Guinea: Bulolo, 2000 ft, 26. xi.1967, rainforest, ANIC Ants vial 17.191 (B. B. Lowery).

Paratypes, 11 workers and 3 queens with same data as holotype (ANIC,, ).