Mayriella granulata

Nests of M. granulata are found in rotting twigs, under stones and in the litter layer (Eguchi et al. 2011)

Identification
This species is similar to Mayriella transfuga and can be separated from it by the presence of relatively short and broad propodeal spines (the spines are at most about as long as the width of their bases while they are at least 1.5 times the width of the base in M. transfuga). It can be separated from the remaining species in the genus by the presence of well developed sculpturing in the posterior section of the scrobe, the large, closely spaced pits on the mesosomal dorsum, the parallel lateral surfaces of the postpetiole and the strongly angular petiolar node. This species may be a slight variant of transfuga but without additional material to assess the variation this form is retained as a good species. (Shattuck and Barnett 2007)

Distribution based on Regional Taxon Lists
Oriental Region: Vietnam.

Biology
Species of Mayriella show strong preference for moist, forested areas. Most specimens have been collected from rainforest or wet sclerophyll woodlands with relatively few collections from dry sclerophyll or scrub habitats (and these are restricted to Australia). Nests are normally found in soil under stones or with a small mound of loose dirt at the entrance. They have also been found nesting in rotten logs and occasionally arboreally. The number of workers in nests averages between 50 and 100 and about one-half of the nest series containing queens contain more than one, suggesting that species are polygynous. Foraging workers are most commonly collected from litter samples. Nests appear to be locally abundant although patchily distributed on a larger scale. For example, in the Brindabella Ranges near Canberra, ACT, Mayriella ebbei is infrequently encountered and is known from only a few localities. However, near Baroomba Rocks (located on the eastern slope of the Brindabella Ranges) M. ebbei occurs commonly under rocks in an area covering several hundred square meters. This population appears limited to this small area as nests could not be found in areas with similar geography and vegetation located several kilometers away. However, observations are limited and additional data will be required to determine if these habits are widespread and/or occur in other species. Additionally, while Taylor (1961) made similar observations for Mayriella abstinens, these were based on the introduced population found in New Zealand and should be confirmed for naturally occurring populations of the genus.

Nomenclature

 *  granulata. Mayriella granulata Dlussky & Radchenko, 1990: 123, figs. 1-3 (w.) VIETNAM. See also: Shattuck & Barnett, 2007: 445.

Worker
Shattuck and Barnett (2007) - Sculpturing in posterior section of antennal scrobe well developed and distinct; sculpturing on dorsal surface of mesosoma consisting of large, closely spaced pits; propodeal spines relatively long and broad; dorsal surface of petiole in lateral profile uniformly convex, without distinct dorsal and posterior faces and forming a sharp angle with the anterior face; in dorsal view, postpetiole with the anterior and posterior regions approximately the same width (the region connecting them either flat or weakly convex); postpetiole and gaster lacking erect hairs dorsally.

Measurements. Holotype - CI 0.98; HL 0.43; HTL 0.22; HW 0.42; ML 0.45; PW 0.30; SI 0.57; SL 0.24.

References based on Global Ant Biodiversity Informatics

 * Dlussky G. M.; Radchenko A. G. 1990. The ants (Hymenoptera, Formicidae) of Vietnam. Subfamily Pseudomyrmicinae. Subfamily Myrmicinae (tribes Calyptomyrmecini, Meranoplini, Cataulacini). Pp. 119-125 in: Akimov, I. A.; Emelianov, I. G.; Zerova, M. D. et al. (eds.) 1990. News of faunistics and systematics. [In Russian.]. Kiev: Naukova Dumka, 184 pp.
 * Eguchi K.; Bui T. V.; Yamane S. 2011. Generic synopsis of the Formicidae of Vietnam (Insecta: Hymenoptera), part I  Myrmicinae and Pseudomyrmecinae. Zootaxa 2878: 1-61.
 * Shattuck S. O., N. J. Barnett. 2007. Revision of the ant genus Mayriella. Memoirs of the American Entomological Institute 80: 437-458.
 * Zryanin V. A. 2011. An eco-faunistic review of ants (Hymenoptera: Formicidae). In: Structure and functions of soil communities of a monsoon tropical forest (Cat Tien National Park, southern Vietnam) / A.V. Tiunov (Editor). – M.: KMK Scientific Press. 2011. 277 р.101-124.