Myrmica schoedli

M. schoedli was found in well-developed secondary forest at altitudes between 1850 and 2200 m and the nest was found under vegetation on a rock, by the side of a stream.

Identification
A member of the draco complex of the ritae species group that includes also Myrmica draco and Myrmica yamanei, from which M. schoedli well differs by its much longer scape (SI1 > 1.23 vs. < 1.18, SI2 > 1.45 vs. < 1.40). Additionally, the head dorsum of M. yamanei has coarse reticulation (vs. longitudinal rugosity in M. schoedli), and the surface of the propodeum is punctated, not smooth. M. draco has a distinctly shorter, not sub-oval head (SI1 < 1.10 vs. > 1.15), the less developed reticulation on the mesonotal dorsum, a deeper metanotal groove and shorter petiole. (Radchenko and Elmes 2010)

Key to Myrmica of Vietnam

Distribution
North Vietnam.

Distribution based on Regional Taxon Lists
Oriental Region: Vietnam.

Nomenclature

 *  schoedli. Myrmica schoedli Radchenko, Elmes & Bui, 2006: 36, figs. 1  10 (w.q.) VIETNAM. Radchenko & Elmes, 2010: 272 (m.). See also: Radchenko & Elmes, 2010: 272.

Worker
Head distinctly longer than broad, with convex sides and occipital margin and very broadly rounded occipital corners, so that head appears sub-oval, its upper latero-ventral corners pointed; anterior clypeal margin very feebly convex, shallowly but distinctly notched medially. Mandibles with 9 - 10 teeth. Frontal carinae feebly curved, frons wide, frontal lobes somewhat raised vertically (i.e., perpendicular to the head dorsum); antennal sockets surrounded by a single ruga and fine additional striae. Antennal scape extremely long, the longest among all known Myrmica species, gradually and weakly curved at the base.

Alitrunk long and low, with feebly convex promesonotal dorsum (seen in profile), promesonotal suture indistinct (seen from above); metanotal groove distinct but shallow; metapleural lobes projecting apically to form sharp teeth. Propodeal spines very long, broad at the base, sharp, straight, projecting backwards at < 45° (seen in profile) and divergent (seen from above). Petiole very long, low and narrow, with long node; its anterior surface concave, node dorsum very feebly convex; postpetiole fig-shaped (seen from above), high, somewhat higher than long, its anterior surface quite steep, slightly convex, node dorsum narrowly rounded (seen in profile). Spurs on middle and hind tibiae well developed and pectinate.

Head dorsum with fine, slightly sinuous longitudinal rugae, without reticulation. Frons between frontal carinae level with the eyes, with no less than eight rugae. Clypeus with fine longitudinal rugulae, mandibles striato-rugulose. Surface of head dorsum between rugae finely though obviously punctated, but appears more or less shiny, while frontal triangle, antennal sockets and clypeus smooth and shiny.

Alitrunk in contrast to head much more coarsely sculptured. Its sides with very coarse longitudinal, more or less straight or slightly sinuous rugae. Promesonotal dorsum with coarse reticulation, propodeal dorsum with longitudinal sinuous rugosity. Surface between rugae smooth and shiny, not punctated. Petiole and postpetiole without rugae, only partly finely striated and punctated, appearing somewhat dull. Gaster smooth and shiny.

Head margins, alitrunk dorsum and waist with sparse, very long outstanding hairs. Antennal scape and tibiae with much shorter hairs. Alitrunk and head brownish-red, gaster brownish-yellow, antennae reddish, legs reddish-yellow.

Measurements (mm) and indices of workers (n = 5) in order minimum - maximum, arithmetic means in parentheses, data of the holotype in brackets: HL 1.08-1.24 (1.12) [1.10], HW 0.89-1.04 (0.94) [0.94], FW 0.33-0.39 (0.35) [0.34], FLW 0.38-0.45 (0.40) [0.39], SL 1.40-1.54 (1.45) [1.44], AL 1.76-1.98 (1.84) [1.82], HTL 1.12-1.24 (1.15) [1.14], PNW 0.66-0.76 (0.70) [0.70], PL 0.55-0.60 (0.57) [0.57], PW 0.23-0.26 (0.24) [0.23], PH 0.26-0.30 (0.27) [0.27], PPL 0.42-0.45 (0.43) [0.43], PPW 0.36-0.42 (0.38) [0.38], PPH 0.44-0.50 (0.45) [0.44], ESL 0.60-0.72 (0.63) [0.61], ESD 0.45-0.54 (0.51) [0.52]. CI 1.17-1.21 (1.19) [1.17], FI 0.36 - 0.38 (0.37) [0.36], FLI 1.14-1.15 (1.15) [1.15], SI1 1.24-1.31 (1.29) [1.31], SI2 1.48-1.57 (1.54) [1.53], PI1 2.00-2.15 (2.08) [2.11], PI2 0.58-0.62 (0.61) [0.61], PPI1 0.90-0.98 (0.95) [0.98], PPI2 1.16-1.21 (1.18) [1.16], PPI3 1.57-1.65 (1.60) [1.65], PPI4 0.40-0.42 (0.40) [0.40], ESLI 0.64-0.63 (0.65) [0.66], ESDI 0.75-0.88 (0.82) [0.85].

Queen
Despite its general resemblance to the workers, the queen differs from them in the following points: head appears less sub-oval, with more distinct though broadly rounded occipital corners, frontal lobes less extended. Scape relatively shorter than that of the workers, but still very long. Propodeal spines distinctly curved downwards, only slightly divergent; petiole relatively shorter and higher, its anterior surface strongly convex, not concave.

Head, alitrunk and waist have a uniformly coarse rugosity, that of the entire alitrunk being longitudinal, more or less straight, and that of petiole and postpetiole being longitudinally-concentric. Head and waist not punctated.

Measurements (mm) and indices of queen (n = 1): HL 1.30, HW 1.14, FW 0.44, FLW 0.49, SL 1.56, AL 2.46, AH 1.50, SCW 1.10, SCL 1.66, HTL 1.44, PL 0.75, PW 0.35, PH 0.41, PPL 0.58, PPW 0.56, PPH 0.62, ESL 0.63, ESD 0.62. CI 1.14, FI 0.39, FLI 1.11, SI1 1.20, SI2 1.37, PI1 1.83, PI2 0.66, PPI1 0.94, PPI2 1.11, PPI3 1.60, PPI4 0.49, ESLI 0.55, ESDI 0.98, AI 1.64, SCI 1.50.

Male
Radchenko and Elmes (2010) - Head slightly longer than broad, with convex sides and occipital margin, and gradually rounded occipital corners; anterior clypeal margin very slightly convex and very shallowly notched medially. Central part of clypeus raised, forming trapezoid lobe-like process when seen in profile. Frontal carinae very feebly curved. Antennal scape short, somewhat shorter than 1st to 3rd basal funicular segments together; antennal club 5-segmented, but not well marked. Masticatory margin of mandibles distinct, with 5 sharp teeth.

Alitrunk relatively long, low and narrow, scutum convex, and scutellum does not project dorsally above scutum when seen in profile. Propodeum with blunt triangular denticles. Propodeallobes not prominent, but angled at the apex. Petiole long and low, with distinct peduncle, with feebly convex and gradually rounded node dorsum; postpetiole also quite long and low, seen from above fig-shaped.

Cell 1 +2r of forewing, in contrast to that of known males of the ritae-group species, is not wide, length / width ratio> 1.65 (see also Radchenko and Elmes 1998; Radchenko et al. 2001).

Frons with fine striae, surface of head not coarsely but densely punctated, clypeus with fine superficial microreticulation; whole surface appears shiny. Scutum behind Mayrian furrows with a few longitudinal rugae, scutellum (except its centnil part) with longitudinally-concentric rugulosity, propodeum with not coarse longitudinal rugosity, mesopleura distally with fine rugulosity; surface of alitrunk smooth and appears shiny. Petiole and postpetiole at most partly finely superficially punctate, mainly smooth and shiny. Gaster smooth and shiny.

Head margins with not abundant but long standing hairs. Alitrunk, petiole, postpetiole and gaster with similar, while somewhat shorter hairs. Legs and scape with short subdecumbent to decumbent hairs. Whole body reddish-brown, head somewhat darker, appendages reddish-yellow.

Type Material
Holotype (worker), northern Cong Troi, Sa Pa district, Lao Cai province, 2000 - 2200 m a.s.l., 28.IV.2002, No. Eg02-VN-152 (GWE No.VN-3), leg. K. Eguchi ; paratypes: 3 workers and 1 queen from the nest of the holotype; same locality, 2100 - 2200 m a.s.l., 5.V.2001, GWE No. VN-4, leg. K. Eguchi, 1 worker (,, VIET).

Etymology
Radchenko and Elmes (2010) - this species was dedicated to the memory of the Austrian entomologist and myrmecologist, Prof. Stefan Schoedl (1957-2005) of the natural History Museum, Vienna.