Crematogaster suehiro, TERAYAMA, 1999

Hosoishi, Shingo & Ogata, Kazuo, 2016, Systematics and biogeography of the ant genus Crematogaster Lund subgenus Orthocrema Santschi in Asia (Hymenoptera: Formicidae), Zoological Journal of the Linnean Society 176 (3), pp. 547-606 : 598-600

CREMATOGASTER SUEHIRO TERAYAMA, 1999

( FIG. 120 )

Crematogaster suehiro Terayama, 1999: 726 , figs. 1–4;

holotype worker and two paratype workers, one paratype queen and one intermediate worker, Ishigaki Island , Japan ( MNHA, not examined) .

Crematogaster miroku Terayama, 2013: 12 , figs 23– 25;

Holotype worker and six paratype workers, Higashison , Kunigami-gun , Okinawa-jima , Okinawa Pref., Japan, 3.xi.2012 (H. Takamine) ( ITLJ, examined; images also examined from Yoshitake et al., 2011). Syn. nov.

Crematogaster suehiro ; Blaimer, 2012c: 55 [Combination in C. ( Orthocrema )].

Worker measurements (n = 6): HW 0.46–0.52; HL 0.47– 0.51; CI 96–102; SL 0.46–0.50; SI 94–100; EL 0.12– 0.14; PW 0.30–0.33; WL 0.54–0.6; PSL 0.11–0.13; PtL 0.18–0.20; PtW 0.16–0.18; PtH 0.14–0.15; PpL 0.12– 0.14; PpW 0.17–0.19; PtHI 74–79; PtWI 85–90; PpWI 123–158; WI 106–112.

General description of worker: Workers monomorphic.

Head subquadratic in full-face view. Mandibles with four teeth arranged at an equal distance, apical and subapical teeth large, basal two teeth smaller. Anterior clypeal margin convex in medial portion. Compound eyes distinctly projecting beyond lateral margins of head in full-face view. Scapes reaching posterolateral corners of head.

Pronotal collar with weakly concave anterior margin in dorsal view, distinctly lower than pronotum in lateral view. Pronotal dorsum without distinct ridges laterally. Mesonotal dorsum with lateral ridges. Pronotum and mesonotum in lateral view not clearly forming continuous dorsal outline. Metanotal groove in dorsal view transverse, almost straight in median portion, forming deep concavity that is laterally margined by lamellate ridges. Propodeal spiracles oval, situated at posterolateral corners of propodeum, touching metapleural gland bullae. Propodeal spines developed, longer than diameter of propodeal spiracles, in dorsal view directed posteriad.

Petiole in dorsal view with subparallel sides and narrow anteriorly, longer than wide. Posterior portion of petiole without distinct process in lateral view. Subpetiolar process weakly developed as small process. Postpetiole in lateral view with weakly convex dorsum, as high as petiole, in dorsal view slightly wider than petiole, weakly bilobed posteriorly but without longitudinal sulcus. Subpostpetiolar process undeveloped, but venter of postpetiole convex.

Integument essentially smooth and shining. Dorsal surface of head smooth and shining. Mandibles with feeble rugulae and smooth interspaces. Clypeus generally smooth and shining, but with one distinct pair of longitudinal longer rugulae and one pair of shorter rugulae laterally; longer rugulae extending to posteri- or clypeal margin. Dorsal and lateral surfaces of pronotum smooth and shining; anterolateral shoulders of pronotum without rugulae. Mesopleura smooth and shining. Dorsal surface of propodeum generally smooth and shining, but with one longitudinal rugulae anteriorly. Dorsal and lateral surfaces of petiole smooth and shining. Dorsal and lateral surfaces of postpetiole smooth and shining.

Standing pilosity sparse. Dorsal face of head with erect setae sparsely. Clypeus with two pairs of long setae in anterior portion, one directed upward and the other downward. Anterior clypeal margin with one pair of long setae medially and short setae laterally. Scapes with suberect setae. Mesosoma with five pairs of long erect and stout setae [ps1PN, ps2PN, psaMN, pspMN (also one pair of short setae medially), and ps1PS] that are much longer than other erect setae. Posterolateral tubercles of petiole posteriorly with two pairs of stout long setae. Postpetiole with four pairs of setae on disc anterodorsally, anterodorsally and posteriorly. Fourth abdominal tergite with erect setae abundantly, and short decumbent setae sparsely.

Body yellow. All flagellar segments yellow.

Comments: We have not examined the types of C. suehiro , but the original description and figures closely match the specimens examined. In the worker this species can be distinguished from all other members of the C. quadriruga group by the distinct compound eyes, propodeal spiracles small and apart from metapleural gland bulla, and petiole tapering anteriorly in dorsal view. This species is similar to C. quadriruga , but can be distinguished from it by the longitudinal rugulae on the clypeus extending to the bottoms between frontal carinae and petiole tapering anteriorly.

In the original description of C. miroku, Terayama (2013) separated the species from C. osakensis by the carinate dorsolateral corners of mesonotum and smooth and shining mesopleuron. However, the original description and character states mentioned by him match well with C. suehiro . Additionally longer scape (SI 96) in holotype of C. miroku also suggests the affinity with C. suehiro (SI 94–100) rather than C. osakensis (SI 77–84). In a key to Japanese Crematogaster species ( Terayama, Kubota & Eguchi, 2014), C. miroku was separated from C. suehiro by the petiole with convex sides and slightly broader posteriorly, but he mentioned ‘ Petiole .., widest at posterior end ’ in the original description ( Terayama, 2013). Those slight differences are treated as variation within one species, C. suehiro until additional characters including molecular data are available.

Distribution and biology: This species is known from Southern parts of Japan (Ishigaki Island, Okinawa Island) ( Fig. 52 ). This species inhabits developed forests, and nests in dead twigs on trees.

Material examined: JAPAN: six workers, Mt. Omoto , Ishigaki Island, 10.x.2008 (M. Maruyama & T. Komatsu) .

Figures

Figure 52. Geographical distribution of the species of the C. quadriruga group.

Figures 120–123. Body in lateral view. 120, Crematogaster suehiro, worker [Mt. Omoto, Ishigaki Island, Japan]; 121, Crematogaster sundalandensis, worker [Maliau Basin (riparian forest), Sabah, Borneo, E. Malaysia]; 122, Crematogaster vieti, worker [near Forestry Station, Khe Kem, Pu Mat National Park, Nghe An, Vietnam]; 123, Crematogaster vieti, intermediate worker [near Forestry Station, Khe Kem, Pu Mat National Park, Nghe An, Vietnam].