Lordomyrma tortuosa

Often collected from leaf litter, nests of small colonies have been found in logs and under stones. Mann (1921) notes that he often found workers of this species foraging on mossy stones in ravines, and I have also observed workers gleaning the surfaces of stones on the banks of rivers. (Sarnat 2016)

Identification
Sarnat (2016) - Lordomyrma tortuosa, together with Lordomyrma desupra, Lordomyrma stoneri and Lordomyrma vuda lacks a transverse carina on the dorsal face of its propodeum posterior to the metanotal groove and possesses a robust promesonotum that bulges above the level of its head and propodeum. It can be readily distinguished from these three by the frontal carinae that join with the arcuate carinae posterior of the eye, and the presence of longitudinal carinae that run immediately inward from the frontal carinae. Although the number and strength of these carinae vary, the variation does not appear to follow a distinguishable geographic pattern.

Distribution
A Fiji endemic. Sarnat (2016): With many records from 8 of the archipelago’s islands, L. tortuosa is far and away the most geographically widespread of Lordomyrma species occurring in Fiji. Lordomyrma tortuosa appears to be restricted to the lower elevations of the islands, with only two of the aforementioned 32 records being recorded from above 500 m.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Fiji.

Nomenclature

 *  tortuosa. Rogeria (Irogera) tortuosa Mann, 1921: 452, fig. 18 (w.) FIJI IS. Combination in Lordomyrma: Kugler, C. 1994: 26. See also: Sarnat, 2006: 33.

Worker
Sarnat (2016) - TL 4.15–4.53, HL 0.93–1.01, HW 0.82–0.90, CI 0.87–0.91, SI 0.69–0.76, REL 0.18–0.24, PSLI 0.96–1.11, MFLI 0.94–1.02, DPWI 1.00–1.11 (10 measured).

A large-sized shiny, reddish brown species with massive promesonotum, modestly-sized straight propodeal spines and strong arcuate carinae on face. In full face view, posterior margin of head evenly convex with gently rounded corners. Clypeus bearing one pair of weak carinae. Frontal carinae strong, becoming confluent with series of arcuate carinae present between eye and posterior corners of head, forming dorsal margin of a broad, poorly defined scrobe. Eyes of moderate size. In profile, shape of promesonotum massive, strongly convex, and bulging above the head and propodeum. Propodeal spines strong, triangular, straight, divergent; in profile when measured from propodeal spiracle roughly equal to the width of the procoxae. Propodeal lobes of moderate size, triangular, stout. Petiole robustly built; anterior face strongly sloped and weakly concave; dorsal face more gently sloping and weakly convex; the rounded apex occurring at the anterior angle. Postpetiole with anterior and dorsal faces evenly convex, apex occurring at midline. Mandibles smooth and shining with scattered setigerous foveolae. Middorsum of head smooth and shining with scattered foveolae; several carinae mesad of frontal carinae, extending continuously or with interruptions from frontal lobes posteriorly to behind the eyes. Frontal lobes with one pair of strong carinae in addition to the frontal carinae. In oblique lateral view, widely separated and strongly elevated arcuate carinae overlaying all dorsal surfaces of head from frontal carinae to ventrolateral carina and from posterior corners to antennal insertions. Promesonotum smooth and shining with scattered foveolae. Procoxae smooth and shining. Sides of mesonotum, metapleuron, and propodeum overlain by coarse, widely-spaced and occasionally intersecting rugae. In dorsal view, dorsal face of propodeum smooth and shining, the anterior margin without a transverse carina posterior to metanotal groove; declivitous face smooth and shining. Petiole with smooth and shining anterior face, banded by coarse transverse rugae that reach the ventral face. Postpetiole coarsely rugoreticulate. Gaster smooth and shining. All dorsal surfaces with an abundance of suberect to erect acuminate hairs, the longest of which equal or exceed the length of the eye. Head, mesosoma and gaster reddish brown with lighter appendages.

Type Material
Sarnat (2016) - Syntypes, workers, Ovalau, Fiji (W.M. Mann).

References based on Global Ant Biodiversity Informatics

 * Dlussky G.M. 1994. Zoogeography of southwestern Oceania. Zhivotnoe naselenie ostrovov Iugo-Zapadnoi Okeanii ekologo-geograficheskie issledovanii 48-93.
 * Lucky A., and E. M. Sarnat. 2008. New species of Lordomyrma (Hymenoptera: Formicidae) from Southeast Asia and Fiji. Zootaxa 1681: 37-46.
 * Mann W. M. 1921. The ants of the Fiji Islands. Bulletin of the Museum of Comparative Zoology 64: 401-499.
 * Sarnat Eli M. 2009. The Ants [Hymenoptera: Formicdiae] of Fiji: Systematics, Biogeography and Conservation of an Island Arc Fauna. 80-252
 * Sarnat, Eli M. 2006. Lordomyrma (Hymenoptera: Formicidae) of the Fiji Islands. Fiji Arthropods VI. 9-42.
 * Wheeler W.M. 1935. Check list of the ants of Oceania. Occasional Papers of the Bernice Pauahi Bishop Museum 11(11):1-56.
 * Wheeler, William Morton.1935.Checklist of the Ants of Oceania.Occasional Papers 11(11): 3-56
 * Wilson E.O., and G.L. Hunt. 1967. Ant fauna of Futuna and Wallis islands, stepping stones to Polynesia. Pacific Insects 9(4): 563-584.
 * Wilson, Edward O. and George L. Hunt. 1967. Ant Fauna of Futuna and Wallis Islands, Stepping Stones To Polynesia. Pacific Insects. 9(4):563-584.
 * Wilson, Edward O. and Hunt, George L. Jr. 1967. Ant Fauna of Futuna and Wallis Islands, Stepping Stones to Polynesia. Pacific Insects. 9(4):563-584