Crematogaster jacindae

The microhabitats where C. jacindae was encountered included leaf litter, soil, under stones, or on native vegetation, especially acacia trees. The majority of specimens were collected foraging on plants using a beating sheet, but workers were also observed foraging on the ground and wild shrubs.

Identification
Crematogaster jacindae sp. nov. is distinguished from related congeners by the combination of the following characters: median mesonotal carina absent; propodeal spines absent; propodeal spiracle distinct in the form of a slit; area in front of eyes finely longitudinally striated; antennal fossae surrounded by fine and curved striolae; head black-brown or black, mesosoma, petiole and postpetiole dark brown, relatively lighter than head, gaster golden yellow.

The distinctive golden yellow gaster and complete lack of propodeal armament of C. jacindae allows this Omani species to be immediately recognized from all other Arabian species. The closest relative of the new species is Crematogaster inermis from Egypt. Both species are similar in body size and the lack of propodeal spines, but C. jacindae can be readily separated by the following characters: area in front of eyes finely longitudinally striated; cephalic surface feebly imbricate; eyes with about 11 ommatidia in the longest row; posterior half of clypeus without hairs or pubescence; mesopleura and metapleura distinctly densely imbricate; mesonotum with a single pair of hairs and without anterior tubercles; propodeal spiracles distinct in the form of a slit; body bicolored with head black-brown or black, mesosoma, petiole and postpetiole dark brown, relatively lighter than head, gaster golden yellow. By contrast, C. inermis has an unsculptured cephalic surface including the area in front of the eyes, eyes with ca. 14 ommatidia in the longest row, the posterior half of clypeus with fine appressed pubescence, mesosoma with a small anterior tubercle close to the promesonotal suture seen in profile; mesopleura and metapleura longitudinally striated, mesonotum without hairs, propodeal spiracle circular, unicolorous black-brown body.

Distribution based on Regional Taxon Lists
Palaearctic Region: Oman.

Nomenclature

 *  jacindae. Crematogaster jacindae Sharaf & Hita Garcia, in Sharaf et al., 2019: 58, figs. 21A-C (w.) OMAN.

Worker
Holotype. EL 0.20; HL 0.75; HW 0.82; LHT 0.55; PPL 0.12; PPW 0.20; PRW 0.42; PTH 0.12; PTL 0.25; PTW 0.22; SL 0.55; ML 0.87; Indices. CI 109; LBI 158; OI 24; PPI 167; PTHI 48; PTWI 88; SI 67. Paratype. EL 0.17–0.22; HL 0.72–0.92; HW 0.75–1.0; LHT 0.52–0.75; PPL 0.12–0.17; PPW 0.15–0.25; PRW 0.32–0.50; PTH 0.12–0.17; PTL 0.20–0.32; PTW 0.20–0.30; SL 0.50–0.95; ML 0.77–1.02; Indices. CI 96–113; LBI 121–165; OI 16–27; PPI 125–208; PTHI 44–68; PTWI 78–125; SI 61–95 (N = 20)

Head. Head as long as or little broader than long with convex sides and feebly concave posterior margin; antennae 12-segmented; in full-face view antennal scapes when laid back from their insertions fail to reach posterior margin of head; eyes of moderate size (OI 16–27), located nearly at mid-length of head in full-face view and with ca. eleven ommatidia in the longest row; anterior clypeal margin broadly convex.

Mesosoma. Promesonotum and mesonotum forming continuous curve in profile; median mesonotal carina absent; metanotal groove well developed; propodeal dorsum short forming curve with longer propodeal declivity; propodeal spines absent; propodeal spiracle distinct and slit-shaped. Petiole. In profile petiole distinctly longer than high (PTHI 44–68; PTWI 78–125); broader anteriorly than posteriorly in dorsal view.

Postpetiole. Postpetiolar node distinctly bilobed in dorsal view; nearly as high as petiole in profile.

Pilosity. Cephalic surface with abundant scattered fine pale hairs; anterior clypeal margin and mandibles with several long yellow hairs; posterior half of clypeus without hairs or pubescence; antennae and legs with abundant appressed pubescence; promesonotum and mesonotum each with single pair of hairs; promesonotum and mesonotum dorsum with appressed pale pubescence; no hairs or pubescence on propodeum; petiole and postpetiole each with single pair of posteriorly directed hairs; gastral pilosity restricted to few pairs on posterior margins of gastral tergites; gastral tergites with scattered appressed pubescence.

Sculpture. Mandibles longitudinally striated; clypeal surface smooth; area in front of eyes finely lon-gitudinally striated; cephalic surface feebly imbricate; antennal fossae surrounded by fine and curved striolae; promesonotum lateral side faintly imbricate; promesonotum dorsum faintly reticulate rugulose; mesopleura, metapleura, petiole, and postpetiole distinctly densely imbricate; gastral tergites faintly imbricate.

Color. Head black-brown or black, mesosoma, petiole and postpetiole dark brown, relatively lighter than head, gaster golden yellow and strongly contrasting with remainder of body.

Type Material

 * Holotype: pinned worker, Oman: Dhofar, Ayn Sahlanoot, 17.14766N, 54.17878E, 151 m, 16.xi.2017 (Sharaf MR) (CASENT0872068, KSMA).
 * Paratype: pinned workers, Oman: Dhofar: Ayn Hamran, 17.08631N, 54.28043E, 56 m, 22.xi.2017, BS (Sharaf MR) (11 w, KSMA, 1 w, CASENT0922856, CASC, 1 w, WMLC); Ayn Razat, 17.12443N, 54.23832E, 98 m, 20.xi.2017, ML (Sharaf MR) (8 w); Dhalkout, 16.72673N, 53.24942E, 623 m, 18.xi.2017, SF (Sharaf MR) (16 w); Dhalkout, 16.70703N, 53.25068E, 34 m, 19.xi.2017, BS (Sharaf MR) (7 w); Dhalkout, 16.69273N, 53.15621E, 628 m, 18.xi.2017, BS (Sharaf MR) (17 w); Ayn Sahlanot, 17.14766N, 54.17878E, 151 m, 16.xi.2017, BS (Sharaf MR) (4 w); Ayn Ashat, 16.99810N, 53.81954E, 202 m, 21.xi.2017, SF (Sharaf MR) (20 w); Dhalkout road, Aghbaroot village, 16.79818N, 53.55392E, 1034 m, 18.xi.2017, BS (Sharaf MR) (1 w) (KSMA).

Etymology
The patronymic epithet has been selected in honor of Ms. Jacinda Ardern, the Prime Minister of New Zealand in recognition of her humanitarian attitudes towards Muslim and minority communities in New Zealand.

References based on Global Ant Biodiversity Informatics

 * Sharaf M. R., S. A. Aldawood, and F. Hita Garcia. 2019. Review of the Arabian Crematogaster Lund (Hymenoptera, Formicidae), synoptic list, distribution, and description of two new species from Oman and Saudi Arabia. ZooKeys 898: 27-81