Myrmecorhynchus carteri

Myrmecorhynchus carteri occurs from north-coastal New South Wales south to Tasmania (it is the only species known from Tasmania). It is found in mallee, thick scrub, dry to wet sclerophyll (including Eucalyptus pauciflora, E. perriniana and E. stellulata forests), coastal scrub (wet scrub; hillside, black soil; at water’s edge) and rainforest. Nests are in dead branches or twigs above the ground (including Acacia sophorae, Eucalyptus perriniana and E. stellulata) or occasionally on the ground, or less commonly in soil under rocks. One nest was found in a dead, rotten branch with a colony of Myrmecorhynchus emeryi; however the relationship between these ants, if any, is unknown. Foragers are commonly found on tree trunks and are known to visit Eucryphia lucida flowers and wander into malaise traps. The larvae were described by Wheeler & Wheeler (1970).

Identification
Mesosomal dorsum with at most a few scattered erect hairs, legs with appressed pubescence but lacking erect hairs; at most a narrow band of yellow on anterolateral clypeal margin; mandibles bicoloured, yellow basally and dark apically; propodeum higher and more rounded and metapleural groove more strongly angled when compared to Myrmecorhynchus nitidus.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  carteri. Myrmecorhynchus carteri Clark, 1934b: 43, pl. 3, figs. 11, 12 (s.w.) AUSTRALIA. Wheeler, G.C. & Wheeler, J. 1970: 648 (l.).

Type Material


Note: A specimen in the (CASENT0903253) from Woori Yallock, Victoria, and labeled as a syntype ("cotype") is not a true type as this locality is not mentioned in the original description of this taxon.

Taxonomic Notes
Morphologically this species is similar to M. nitidus, differing in colour pattern and the shape of the metanotal groove and propodeum. While colour pattern shows considerable variation in Myrmecorhynchus emeryi, this does not seem to be the case here. All known specimens show either the M. carteri or M. nitidus patterns with no intermediate individuals being found. Thus colour suggests that these two taxa are distinct. The shape of the metanotal groove and propodeum also support this conclusion. All known specimens of M. carteri have the propodeum higher and more rounded dorsally compared to M. nitidus workers, resulting in the metanotal groove being more distinct and angular. As with colour, all specimens show one or the other pattern with intermediate forms unknown. Combined, these characters suggest that two separate taxa are involved rather than a single variable species.