on a variety of color patterns, including the typical patterns seen in L. cnemidatus and L. erythrocephalus; workers with different color forms have even been observed in a single nest. Many individuals possess mot- tled brown-black coloration on the head and , which is not seen in either L. cnemidatus or L. eryth- rocephalus. L. wiburdi workers evidently mimic workers of co-occurring species of Leptomyrmex. L. wiburdi has been recorded in , wet sclerophyll and dry sclerophyll. Nests occur in soil, in standing or fallen trees or snags, in stumps, and under rocks.

† Leptomyrmex neotropicus Baroni Urbani

Leptomyrmex neotropicus Baroni Urbani, 1980: 4, fig. 1–5. Camponotus neotropicus Wilson, 1985: 34. Combination in Camponotus Leptomyrmex neotropicus Baroni Urbani & Wilson 1987: 2. Combination in Leptomyrmex

Type material not examined L. neotropicus Baroni Urbani. Holotype [Do-996-K-1] and paratypes, totaling 10 workers from a single block of Dominican amber [SMNS].

Other material examined Dominican Amber: 2 workers [PSWC, MCZ]. These amber specimens resemble Leptomyrmex in the following characters: hypostomal notch present and u-shaped, scapes exceeding the postocular margin by approximately half their length, many teeth and den- ticles, integument thin and lacking sculpture, limbs long and slender, body overall gracile, elongate. These characters suggest an affinity with the extant Leptomyrmex species, but given the disjunct distribution of the fossils and the living species it is likely that L. neotropicus belongs to a stem lineage of this , a fact which should be taken into account when using the fossils for age calibrations in phylogenetic studies. The sister group of Leptomyrmex is a comprised of the two Neotropical genera, and , and it has been suggested that L. neotropicus might represent a stem species in the latter clade (Ward et al. 2010).

Micro-Leptomyrmex

The following six species currently comprise the recently described micro-Leptomyrmex. All occur in eastern Australian . Further species belonging to this group are expected to occur in and . Details of these species, including descriptions, known geographic distributions, and a key to the identification of all known species can be found in Smith and Shattuck (2009). Leptomyrmex aitchisoni-group: L. aitchisoni L. burwelli L. dolichoscapus L. garretti L. pilosus L. ramorniensis

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