Comprehensive DescriptionRead full entry
The status of Ancyridris HNS Wheeler
A. polyrhachioides Wheeler HNS , 1935: 2, fig. 1, a-c; Mt. Misim, PAPUA NEW GUINEA.
Ancyridris HNS (Figs 19, 20) is the only putatively endemic ant genus known from New Guinea. It was provisionally cited as a junior synonym of Lordomyrma HNS by Brown (1973: 178), but subsequently listed by him with generic status (Brown, 2000: 47). The suggested synonymy was not followed by Bolton (2003, et al.), and is declined here. Recent studies investigating DNA affinities among a number of myrmicine ants could indicate that the Ancyridris HNS species comprise a sister group to the rump of Lordomyrma HNS (Lucky, Sarnat & Ward pers.coms). Its species could, however, be considered a lineage within the Lordomyrma clade HNS .
The genus is singularly morphologically distinctive and surprisingly species-rich, yet its taxa are structurally only modestly interspecifically diversified. Ancyridris HNS appears to be limited to elevations above about 1,500 m. in the New Guinean cordillera, often at altitudes above those where ants are otherwise generally well represented. It includes a compact set of at least six undescribed species ( ANIC ) in addition to L. polyrhachioides HNS and L. rupicapra HNS . Its members are very alike, with considerable interspecific size variation; usually largely blackish-brown in color (though the 'red goat', A. rupicapra HNS , is reddish-brown) and generally strongly shining, with at most very weak sculpturation, sparse pilosity and strongly developed, elongate, divergent, apically hooked propodeal spines. The anterior clypeal border carries a median point, the frontal carinae and antennal scrobes are vestigial, the petiole strongly and distinctively dorsolaterally bispinose and the postpetiole usually conical above, the antennae are 12-merous and the palpal formula 3:2 in 4 examined species. The clypeal structure, hooked propodeal spines, paired petiolar spines and dorsally extended postpetiole distinguish Ancyridris HNS from Lordomyrma HNS . Differently configured bilateral petiolar spines are present in Lordomyrma rouxi HNS (Figs 17, 18), but they almost certainly represent a homoplasy.
Available specimens are from scattered sites in Papua New Guinea, with very few known from Indonesian West Papua. Sets of up to four sympatric or near-sympatric species are represented, and sympatric associations with Lordomyrma HNS species are unknown. Ancyridris HNS species are as distinctive and bizarre as some of the derivative lowland New Guinean Lordomyrma HNS species. Despite this, their interspecific morphological diversity is relatively low and quite different in degree from that seen among the structurally diverse lowland New Guinean and New Caledonian Lordomyrma HNS species. The genus compares most closely in the nature of its diversity to the Fijian Lordomyrma fauna HNS (see above).
One species from moss forest on Mt Kaindi near Edie Creek (07o21'S, 146o40'E) is a morphologically specialized workerless parasite collected from the nest of another free-living species. Two additional sympatric free-living species are found in the vicinity.
The prospects for discovery of further such sympatric assemblages of Ancyridris HNS species, including additional undescribed taxa, could relate directly to the large number of myrmecologically unexplored high mountain blocs on New Guinea. This significant group is surely not yet well represented in collections.