| Strumigenys loriae|
Known from rainforest habitats, S. loriae has been foudn in rotten wood, in soil under wood and in a litter sample.
Bolton (2000) - A member of the Strumigenys loriae-group. As well as the size-related variation mentioned above the measurements also express aspects of the polymorphism of this species. For instance, as HW increases CI also tends to increase, especially in the upper part of HW range; and the largest individuals have the lowest SI. Remarkably, MI remains very stable through the entire range of HL so that the relative length of the mandible always stays about the same, regardless of the size of the individual.
Of the seven species in this group Strumigenys pachycephala, Strumigenys chyzeri and Strumigenys odalatra are easily isolated. The first is the only one to lack a preapical tooth on the mandible; the second is the only one in which the preapical mandibular tooth arises from the dorsal surface of the mandible rather than from its inner margin; the third is the only member of the group to have erect long fine hairs freely projecting from the middle and hind basitarsi.
The remaining four fall into two species-pairs: Strumigenys festigona plus Strumigenys loriae, which have reticulate-punctate postpetiole discs and basigastral costulae that are at least as long as the postpetiole disc; and Strumigenys kyroma plus Strumigenys retothra in which the postpetiole discs are usually smooth and the basigastral costulae are distinctly shorter than the postpetiole discs.
As well as being polymorphic loriae separates from the monomorphic festigona on the shape of the preocular projection of the head’s ventrolateral margin. In loriae it is always blunt and more or less straight. In festigona it is acute and thorn-like, curved anteriorly and with a concave anterior margin and convex posterior margin. The bullae of the femoral and tibial glands of the hind leg also differ in the material available. The femoral gland bulla in loriae is minute or invisible, when visible always smaller and less distinct than the bulla of the tibial gland. In festigona the femoral gland bulla is always conspicuous and about equal in size to that on the tibia.
Keys including this Species
Distribution based on Regional Taxon Lists
Check distribution from AntMaps.
Distribution based on specimens
Strumigenys were once thought to be rare. The development and increased use of litter sampling methods has led to the discovery of a tremendous diversity of species. Many species are specialized predators (e.g. see Strumigenys membranifera and Strumigenys louisianae). Collembola (springtails) and other tiny soil arthropods are typically favored prey. Species with long linear mandibles employ trap-jaws to sieze their stalked prey (see Dacetine trap-jaws). Larvae feed directly on insect prey brought to them by workers. Trophallaxis is rarely practiced. Most species live in the soil, leaf litter, decaying wood or opportunistically move into inhabitable cavities on or under the soil. Colonies are small, typically less than 100 individuals but in some species many hundreds. Moist warm habitats and micro-habitats are preferred. A few better known tramp and otherwise widely ranging species tolerate drier conditions. Foraging is often in the leaf litter and humus. Workers of many species rarely venture above ground or into exposed, open areas. Individuals are typically small, slow moving and cryptic in coloration. When disturbed individuals freeze and remain motionless. Males are not known for a large majority of species.
The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.
- loriae. Strumigenys loriae Emery, 1897c: 576, pl. 14, fig. 3 (w.) NEW GUINEA. Szabó, 1910a: 368 (q.). Senior synonym of excisa: Brown, 1949d: 15. See also: Bolton, 2000: 862.
- excisa. Eneria excisa Donisthorpe, 1948d: 598, fig. 1 (w.q.) NEW GUINEA. Junior synonym of loriae: Brown, 1949d: 15.
Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.
Bolton (2000) - TL 3.1-5.1, H L 0.96-1.64, HW 0.82-1.60, CI 83-99, ML 0.40-0.67, MI 39-44, SL 0.52-0.88, SI 53-69, PW 0.37-0.55, AL 0.90-1.34 (polymorphic species, 25 measured). In full-face view side of head in front of preocular impression expanded and projecting laterally; in smallest workers the expansion a low rounded tumulus, in larger workers bluntly triangular, bluntly conical or thickly boss-like. Cephalic dorsum with fine rugulose sculpture overlying reticulate-punctation in larger workers; in smaller workers the rugulae reduced or sometimes absent. Dorsolateral margin of occipital lobe with a few short stiff projecting hairs that are apically blunt or slightly expanded. In profile cephalic dorsum with short stiff standing hairs present from just behind level of eye to occipital margin, but absent from concavity of transverse dorsal impression. Pleurae and side of propodeum reticulate-punctate; in smallest workers katepisternum may be less strongly sculptured than metapleuron and side of propodeum. Propodeal spines long and strong, with a tendency to be weakly upcurved. Bulla of femoral gland on hind leg usually invisible, when discernible small and inconspicuous, smaller than the conspicuous bulla of the hind tibial gland. Dorsal (outer) surfaces of middle and hind basitarsi without erect long fine simple hairs. Petiole node subconical in profile, the lateral spongiform lobe little more than an extension of the collar. Depth of ventral spongiform strip on petiole less than half depth of peduncle but extends whole length of petiole; often of about equal depth throughout its length. Petiole node in dorsal view distinctly broader than long. Disc of postpetiole reticulate-punctate. Basigastral costulae at least equal in length to disc of postpetiole, usually longer. Hairs on first gastral tergite stiff and apically blunt, either simple or somewhat flattened and expanded toward the apex. Strongly polymorphic species.
Bolton (2000) - In several collections workers of loriae have been found mounted upon the same pins as specimens of Strumigenys chyzeri.
- Bolton, B. 1995b. A new general catalogue of the ants of the world. Cambridge, Mass.: Harvard University Press, 504 pp. (page 397, catalogue)
- Bolton, B. 2000. The ant tribe Dacetini. Mem. Am. Entomol. Inst. 65: 1-1028 (page 862, figs. 461, 485 worker described)
- Brown, W. L., Jr. 1949f. Revision of the ant tribe Dacetini. I. Fauna of Japan, China and Taiwan. Mushi 20: 1-25 (page 15, senior synonym of excisa)
- Emery, C. 1897c. Formicidarum species novae vel minus cognitae in collectione Musaei Nationalis Hungarici quas in Nova-Guinea, colonia germanica, collegit L. Biró. Természetr. Füz. 20: 571-599 PDF (page 576, pl. 14, fig. 3 worker, queen described)
- Emery, C. 1924f . Hymenoptera. Fam. Formicidae. Subfam. Myrmicinae. [concl.]. Genera Insectorum 174C: 207-397 (page 321, catalogue)
- Szabó, J. 1910a. Formicides nouveaux ou peu connus des collections du Musée National Hongrois. [part]. Ann. Hist.-Nat. Mus. Natl. Hung. 8: 364-368 (page 368, queen described)
- Wheeler, G. C.; Wheeler, J. 1960b. Supplementary studies on the larvae of the Myrmicinae (Hymenoptera: Formicidae). Proc. Entomol. Soc. Wash. 62: 1-32 (page 26, larva described)