Strumigenys rofocala

Collections of this species show S. rofocala inhabits rainforest leaf-litter.

Identification
Bolton (2000) - A member of the rofocala complex in the Strumigenys godeffroyi-group. Degree and intensity of sculpture on the pronotal dorsum is variable in this species but is never strongly evenly reticulate-punctate. The majority of samples examined fall within the limits given for the type-series, described above, but in some it is more extensive, with superficial punctulate sculpture traversed by feeble longitudinal rugulae over most of the surface.

The minute S. rofocala differs from both Strumigenys baal and Strumigenys edaragona in size, by having the pronotal dorsum less strongly sculptured, and by lacking a strongly differentiated apicoscrobal hair. It also differs from baal as the latter is larger, has the lateral alitrunk extensively sculptured, has the petiole node in profile longer and lower (anterior face of node much shorter than dorsum), and has the apical antennomere more gradually and evenly tapering basally.

S. rofocala is closely related to the less common and more local species Strumigenys datryx, Strumigenys tenitecta and uichancoi, all of which are also very small and of similar habitus. Of these, Strumigenys datryx and tenitecta have flagellate hairs present on the hind basitarsus and have the base of the apical antennal segment broad and broadly articulated to the preapical antennomere. In rofocala and uichancoi the hind basitarsus lacks flagellate hairs and the apical antennal segment is strongly constricted at the base and very narrowly articulated to the preapical segment. These two species separate easily as in rofocala the propodeal tooth in profile is elevated, its dorsal margin angling upwards away from the line of the propodeal dorsum, and the occipital margin bears a transverse row of erect hairs that are conspicuously the longest hairs on the cephalic dorsum. Conversely, in uichancoi the propodeal tooth in profile has its dorsal surface continuing the line of the propodeal dorsum or even shallowly sloping downward, and the occipital margin does not have erect hairs that are conspicuously the longest on the cephalic dorsum.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Indonesia, Malaysia.

Nomenclature

 *  rofocala. Strumigenys rofocala Bolton, 2000: 817 (w.q.) BORNEO

Worker
Holotype. TL 1.8, HL 0.49, HW 0.34, CI 69, ML 0.22, MI 45, SL 0.28, SI 82, PW 0.21, AL 0.50. Characters of rojocala-complex. Base of sixth antennomere very narrow, strongly constricted to its articulation with the preapical segment. Dorsolateral margin of head from level of apex of scrobe to occipital corner with a row of 4-5 freely projecting short curved hairs. These hairs tend to decrease slightly in length posteriorly but all are of similar form; there is no single apicoscrobal hair that is of different structure or much greater length. Cephalic dorsum with a transverse row of 4-6 stiffly erect simple hairs at the occipital margin; anterior to this the head with short ground pilosity that is straight, elevated and inclined anteriorly, but without erect hairs similar to those at the occipital margin. Pronotal humeral hair flagellate (in paratypes frequently looped apically, apices broken off in some). Dorsum of pronotum and mesonotum each with a single pair of erect hairs; pronotal pair usually inclined anteriorly. Dorsum of pronotum with sculpture faint and superficial, not strongly reticulate-punctate. Pronotal surface may be weakly shagreenate or punctulate in places, or sculpture may be partially effaced; some members of type-series with a few fine feeble longitudinal rugulae, some with areas that appear almost smooth (see comment on non-paratypic workers, below). Mesonotum superficially punctulate, the sculpture tending to fade out posteriorly on propodeal dorsum. Pleurae and side of propodeum smooth. Dorsum of petiole node finely punctulate; disc of postpetiole smooth. Lateral spongiform lobe of petiole moderately large, in profile the lobe extends forward to just beyond midlength of node but does not attain the anterior face of the node; in same view height of anterior face of node about equal to length of dorsum. Basigastral costulae slightly shorter than disc of postpetiole. First gastral tergite with simple standing hairs.

Paratypes. TL 1.8, HL 0.49-0.51, HW 0.34-0.35, CI 68-69, ML 0.22-0.24, MI 45-48, SL 0.28-0.29, SI 80-85, PW 0.20-0.22, AL 0.50-0.52 (10 measured).

Dimensions of non-paratypic workers. TL 1.8-1.9, HL 0.48-0.52, HW 0.33-0.35, CI 68-73, ML 0.22-0.24, MI 46-49, SL 0.27-0.30, SI 80-86 (10 measured).

Type Material
Holotype worker, Malaysia: Sarawak, 4th Div., Gn. Mulu Nat. Pk, RGS Expd., Long Pala, 24.ix.1977, lowland rainforest, leaf litter (B. Bolton).

Paratypes. 10 workers and 1 queen with same data as holotype; 3 workers with same data but 29.ix.1977; 9 workers with same data but 6.x.1977; 5 workers and 1 queen with same data but 12.x.1977; 9 workers with same data but 22.x.1977 (BMNH,, , , , ).

Determination Clarifications
This species was misidentified as Strumigenys uichancoi in Bolton, 1998b: 92.

References based on Global Ant Biodiversity Informatics

 * Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65
 * Mezger, D.; Pfeiffer, M. 2010. Ecological traits indicate niche differentiation in Bornean Dacetine species (Myrmicinae; Formicidae). Ecotropica 16: 51-57.
 * Pfeiffer M., D. Mezger, and J. Dyckmans. 2013. Trophic ecology of tropical leaf litter ants (Hymenoptera: Formicidae) - a stable isotope study in four types of Bornean rain forest. Myrmecological News 19: 31-41.
 * Pfeiffer M., and D. Mezger. 2012. Biodiversity Assessment in Incomplete Inventories: Leaf Litter Ant Communities in Several Types of Bornean Rain Forest. PLoS ONE 7(7): e40729. doi:10.1371/journal.pone.0040842
 * Pfeiffer M., and D. Mezger. 2012. Biodiversity Assessment in Incomplete Inventories: Leaf Litter Ant Communities in Several Types of Bornean Rain Forest. PLoS ONE 7(7): e40729. doi:10.1371/journal.pone.0040971
 * Pfeiffer M., and D. Mezger. 2012. Biodiversity Assessment in Incomplete Inventories: Leaf Litter Ant Communities in Several Types of Bornean Rain Forest. PLoS ONE 7(7): e40729. doi:10.1371/journal.pone.0041038
 * Pfeiffer M., and D. Mezger. 2012. Biodiversity Assessment in Incomplete Inventories: Leaf Litter Ant Communities in Several Types of Bornean Rain Forest. PLoS ONE 7(7): e40729. doi:10.1371/journal.pone.0041128
 * Pfeiffer M.; Mezger, D.; Hosoishi, S.; Bakhtiar, E. Y.; Kohout, R. J. 2011. The Formicidae of Borneo (Insecta: Hymenoptera): a preliminary species list. Asian Myrmecology 4:9-58