Crematogaster dhofarensis Sharaf, 2025

Crematogaster dhofarensis Sharaf View in CoL sp. n.

( Figure 1 View Figure 1 (A – C))

Holotype

Pinned worker, Oman: Dhofar Governorate, Madinat Alhaqq , 17.1769°N, 54.4208°E, 767 m, 13. August. 2023 ( A. Polaszek) ( CASENT0923770 , Natural History Museum, London, UK). GoogleMaps

Measurements. EL 0.27; HL 0.88; HW 0.92; ML 1.02; PPL 0.25; PSL 0.33; PSD 0.07; PTL 0.19; PPW 0.29; PTW 0.31; PW 0.58; SL 0.83; TL 3.77. Indices: CI 105; EI 30; PSI 32; SI 90.

Diagnosis

Crematogaster dhofarensis sp. n. is separated from related species by the following combination of characters: eyes relatively large, with eye length 0.29 × head width (EI 30); promesonotal suture with a distinct tubercle; metanotal groove broad and deep; propodeal spines in profile remarkably long, thin and acute, making an angle of about 140° with mesosomal longitudinal axis; mesonotum and propodeal dorsum regularly finely striated.

Worker

Head. In full-face view, head slightly broader than long with convex sides and nearly straight or feebly concave posterior margin; in full-face view, scapes when laid back from their insertions just reach posterior margin of head; eyes relatively large, with eye length 0.29 × head width (EI 30), located nearly behind mid-length of head in full-face view and with about 15 ommatidia in longest row; median anterior clypeal margin nearly straight or shallowly concave. Mesosoma. Seen in profile view, mesonotum with a distinct tubercle on promesonotal suture; mesonotum outline straight, with the posterior margin steeply descending to a deep metanotal groove; propodeal dorsum distinctly convex; propodeal spines remarkably long, thin, and acute (PSI 32), making an obtuse angle of about 140° with mesosomal longitudinal axis; at least 4.5 × longer than propodeal spiracle diameter; propodeal spiracle nearly oval, located below base of propodeal spines. Petiole. In profile petiole distinctly longer than high; broader anteriorly than posteriorly in dorsal view; subpetiolar process prominent. Postpetiole. Postpetiolar node distinctly bilobed dorsally. Pilosity. Cephalic surface, antennae, and legs with abundant scattered fine pale appressed pubescence; anterior clypeal margin with a row of several long pale setae; mesosomal dorsum without projecting setae; only sparse scattered appressed pubescence on dorsal and lateral sides; petiole with a single pair of backward-directed setae; postpetiole without setae; gastral pilosity restricted to sparse scattered pubescence on gastral tergites. Sculpture. Mandibles longitudinally rugulose; clypeal smooth medially, finely striated on each side of midline; area in front of eyes finely and superficially longitudinally striated; cephalic surface feebly striated; median area of head and ground surface smooth and shining; mesosoma in dorsal view with irregularly striated promesonotum; mesonotum and propodeal dorsum finely regularly striated; mesosonotum and metanotum longitudinally striated; lateral sides of petiole and postpetiole finely and densely punctulate; petiole and postpetiole dorsum smooth; gastral tergites smooth and shining. Colour. Bicoloured species with body brown to red-brown, gaster distinctly black brown to black.

Etymology

Crematogaster dhofarensis refers to the type locality of the new species.

Geographic range

This new species is known only from Oman.

Differential diagnosis

The new species is similar to C. melanogaster from South Africa in terms of body colour, the remarkably long and acute propodeal spines (PSI 31–32), and the deeply impressed metanotal groove. However, C. dhofarensis can be readily separated by the relatively larger eyes (EI 30) vs TL 4.4 and EI 25 in C. melanogaster , the lack of body pilosity except for the anterior clypeal margin that has several pairs of long setae, whereas C. melanogaster has abundant setae scattered all over the entire body surface. In addition, C. dhofarensis has a superficial cephalic sculpture with a shiny appearance, while C. melanogaster has a densely and finely longitudinally striated cephalic surface with a dull appearance. In the key to Arabian Crematogaster (Sharaf et al. 2019) C. dhofarensis will key to couplet 10 along with C. senegalensis and C. flaviventris . We modify couplet 10 herein to separate the three species.

10 Bicoloured species with golden yellow gaster contrasting with dark brown body; head, mesosoma, petiole, and postpetiole densely shagreened, general appearance dull ................................................................................................................ C. flaviventris Santschi

– Bicoloured species with bark brown to black-brown gaster contrasting with lighter brown body; head, mesosoma, petiole, and postpetiole weakly and variously sculptured, with more or less shining appearance ........................................................................ 11

11 Propodeal spines about twice as long as their base; subpetiolar process lacking; promesonotum with two pairs of short setae; occiput when seen in dorsal view smooth .......................................................................................................... C. senegalensis Roger

– Propodeal spines distinctly more than twice as long as their base; subpetiolar process well-developed; promesonotum dorsum without setae; occiput when seen in dorsal view finely transversally rugulose ............................ ............................ C. dhofarensis sp. n.