A New Species of the Ponerine Ant Genus Myopias Roger from Yunnan , China , with a Key to the Known Oriental Species

The ponerine ant genus Myopias Roger, 1861 is distributed in the Oriental, Indo-Australian, and Australasian regions of the world (Bolton, 1995). Before this study, 38 species were recorded in the world (Bolton, 2013). According to the distribution data of species, most species are known from New Guinea and Indonesia, while some species are distributed south to Australia, and north to China and India. Ten species are known from the Oriental region sensu stricto. The first of these, M. amblyops, was described by Roger (1861) from Sri Lanka. This was followed by M. philippinensis from the Philippines (Menozzi, 1925), M. lobosa from the Philippines and M. nops from Taiwan, China (Willey & Brown, 1983), and M. conicara from China (Xu, 1998). Besides, Stitz (1925) described a subspecies, M. bidens polita, from the Philippines. Recently, Bharti & Wachkoo (2012) described M. shivalikensis from India, and Abstract A new species of the ponerine ant genus Myopias Roger, 1861 collected from southwestern China is described based on morphological features. M. daia sp. nov. is allied to M. luoba Xu & Liu, 2012, but differs from the latter by the shape of the posterior head margin, eye facet number, petiolar node shape, head sculpture, body color, and total length. The new species is also allied to M. nops Willey & Brown, 1983 and M. menba Xu & Liu, 2012, but differs from the latter two species by petiolar node shape, eye facet number, and body sculpture and color. A key based on the worker caste is provided to the eleven known Oriental species of the genus for the first time. Sociobiology


Introduction
The ponerine ant genus Myopias Roger, 1861 is distributed in the Oriental, Indo-Australian, and Australasian regions of the world (Bolton, 1995).Before this study, 38 species were recorded in the world (Bolton, 2013).According to the distribution data of species, most species are known from New Guinea and Indonesia, while some species are distributed south to Australia, and north to China and India.Ten species are known finally, Xu & Liu (2012) described M. hania, M. luoba and M. menba from China.
A survey of ants in Yunnan Province, China, conducted during the Queensland Chinese Academy of Sciences (QCAS) Biodiversity Project, has discovered a new species of Myopias described below.This brings the number of Oriental Myopias species to eleven.In order to identify the Oriental species and understand the differences between the new species and previously known ones, we provided a key for the worker caste based on the specimens of southwestern Chinese species, AntWeb images, and original descriptions.

Materials and Methods
A single worker of the new species was collected from an altitudinal transect in tropical rainforest near Bubeng Village in Mengla County, Xishuangbanna Prefecture.The transect ReseARCH ARtICLe -ANts consisted of twenty square survey plots (20m by 20m), five plots (1-5) at each of four elevations, roughly 600, 800, 1000, and 1200 meters above sea level.At each survey plot ants were extracted from two square meters of leaf litter and from spraying the trunks of 10 large trees.But only leaf litter extraction ('Berlese') yielded the specimen of Myopias.Details of the methods are presented in Burwell & Nakamura (2011).
The key is based on the AntWeb images available for most species, the figure and description of M. philippinensis, and specimens of the southwestern Chinese species.
Descriptions and measurements were made under a Jiangnan XTB-1 stereo microscope with a micrometer at 60× magnification.Illustrations of the new species were made under a Motic-700Z stereo microscope with illustrative equipment at 60× magnification.Images were captured using a Zeiss Discovery V20 stereo microscope with Zeiss AxioCam HRc CCD and Axio Vision Release 4.8.2 software.
Standard measurements and indices are as defined in Bolton (1975), with the addition of ED and MSL outlined below: TL-Total Length: The total outstretched length of the individual, from the mandibular apex to the gastral apex.
HL-Head Length: The straight-line length of the head in perfect full-face view, measured from the mid-point of the anterior clypeal margin to the midpoint of the posterior margin.In species where one or both of these margins is concave, the measurement is taken from the mid-point of a transverse line that spans the apices of the projecting portions.
HW-Head Width: The maximum width of the head in fullface view, excluding the eyes.
SL-Scape Length: The straight-line length of the antennal scape, excluding the basal constriction or neck.
ED-Eye Diameter: The maximum diameter of the eye.
ML-Mandible Length: The straight-line length of the mandible measured from apex to the lateral base.
PW-Pronotal Width: The maximum width of the pronotum measured in dorsal view.
MSL-Mesosoma Length (=AL-Alitrunk Length): The diagonal length of the mesosoma in lateral view, measured from the point at which the pronotum meets the cervical shield to the posterior basal angle of the metapleuron.
PL-Petiole Length: The length of the petiole measured in lateral view from the anterior process to the posteriormost point of the tergite, where it surrounds the gastral articulation.
PH In full-face view head roughly rectangular, longer than broad.Posterior margin straight, posterior corners bluntly angled.Sides weakly convex.Mandible elongate triangular, inner margin about 1/3 length of masticatory margin, basal corner bluntly angled; masticatory margin with a large basal tooth, a large middle tooth, a small preapical tooth, and a small apical tooth.Median clypeal lobe trapezoidal and widened forward, broader than long, length : width = 3:4, anterior margin weakly convex.Antenna 12-segmented, apex of scape fails to reach posterior head corner by 1/2 apical scape width.Eye small, with 9 facets, located at anterior 1/4 of the head side.
The whole body surface smooth and shining.Mandibles smooth and shining.Head with sparse erect to suberect hairs and abundant erect to suberect pubescence.Mesosoma, petiole, and gaster with sparse erect to suberect hairs and abundant subdecumbent to decumbent pubescence.Scapes and tibiae with sparse suberect hairs and dense decumbent pubescence.Body color reddish brown.Mandibles, antennae, legs, and gastral apex yellowish brown.Eyes blackish brown.
Comparative notes: This new species is allied to M. luoba Xu & Liu, 2012, but differs from the latter by having straight posterior head margin in full-face view.Eye with 3 facets in the maximum diameter.In lateral view petiolar node weakly narrowed dorsally, anterior and posterior margins not parallel.Subpetiolar process ventrally pointed, anterior margin oblique, posterior margin weakly sinuate.In dorsal view posterior margin of petiolar node weakly concave.Head smooth and shining.Body color reddish brown.Total length 4.3 mm.While in M. luoba, posterior head margin slightly concave in fullface view.Eye with 6 facets in the maximum diameter.In lateral view petiolar node not narrowed dorsally, anterior and posterior margins parallel.Subpetiolar process anteroventrally pointed, anterior margin nearly vertical, posterior margin weakly concave.In dorsal view posterior margin of petiolar node straight.Head densely finely punctured.Body color blackish brown.Total length 3.8 mm The new species is also allied to M. nops Willey &Brown, 1983 andM. menba Xu &Liu, 2012, but differs from the latter two species by petiolar node slightly narrowed dorsally in lateral view, posterodorsal corner bluntly angled, with distinct angle.Eyes larger, with nine facets.Head, mesosoma and petiole smooth and shining.Body color reddish brown.While in the latter two species, their petiolar node distinctly narrowed dorsally in lateral view, posterodorsal corner rounded, without distinct angle.Eyes absent or very small, with only two facets.Head, mesosoma and petiole finely reticulate or densely punctured.Body color brownish yellow.

Etymology:
The specific epithet has been named after a minority group called "Dai", residing in the Bubeng village locality, Yunnan Province, China.