Key to Arabian Crematogaster

This key to Crematogaster workers from Arabia is based on Sharaf & Aldawood (2019) as modified by Sharaf & Aldawood (2022).

1

 * Postpetiole not bilobed dorsally (Fig. 1A) Crematogaster gryllsi
 * Postpetiole bilobed dorsally (Fig. 1B)

2

 * Propodeal spines completely absent (Fig. 1C)
 * Propodeal spines present, ranging from small denticles to long (Fig. 1D)

3

 * Unicolorous yellow-brown to brown species; cephalic surface including area in front of eyes unsculptured; eyes with ca. 14 ommatidia in longest row; posterior half of clypeus with fine appressed pubescence; mesonotum in profile with a small tubercle close to promesonotal suture; mesopleura and metapleura longitudinally striated; mesonotum without hairs; propodeal spiracles circular (Fig. 1E) Crematogaster inermis
 * Bicolored species, head black-brown or black, mesosoma, petiole and postpetiole dark brown, relatively lighter than head, gaster golden yellow; area in front of eyes finely longitudinally striated; cephalic surface feebly imbricate; eyes with ca. 11 ommatidia in longest row; posterior half of clypeus without hairs or pubescence; mesonotum in profile without tubercle; mesopleura and metapleura distinctly densely imbricate; mesonotum with a single pair of hairs; propodeal spiracles slit-shaped, gaster golden yellow (Fig. 1F) Crematogaster jacindae

4

 * Propodeal spines reduced to a small denticle Crematogaster delagoensis
 * Propodeal spines well developed

5

 * In full-face view, antennal scapes short, clearly not reaching posterior margin of head (Fig. 2A)
 * In full-face view, antennal scapes longer, clearly reaching or surpassing posterior margin of head (Fig. 2B)

6

 * Propodeal spines short and blunt, approx. as long as their bases in profile; antennal fossae surrounded by curved striolae in full-face view (Figs. 2A, 2C) Crematogaster aegyptiaca
 * Propodeal spines long and acute, distinctly longer than their bases in profile; antennal fossae surrounded by longitudinal striolae in full-face view (Figs. 2D, 2E)

7

 * Body distinctly opaque; cephalic surface completely densely longitudinally rugulose; head, mesosoma, petiole and postpetiole reddish (Fig. 2F) Crematogaster mimosae
 * Body shining; only area in front of eyes faintly longitudinally rugolose; head, mesosoma, petiole and postpetiole uniform yellow or brown

8

 * Body uniform yellow; propodeal spine in profile distinctly shorter than its base (Fig. 3A); propodeum dorsum seen from above faintly longitudinally striated (Fig. 3B) Crematogaster acaciae
 * Body Brown-black to black; propodeal spine distinctly longer than its base (Fig. 3C); propodeum dorsum seen from above faintly punctate (Fig. 3D)

8A

 * Promesonotum without hairs (Fig. 3C); propodeal spine in profile nearly twice longer than its base and tapering apically; subpetiolar process present (Fig. 3C) Crematogaster chiarinii
 * Promesonotum with a single pair of hairs (Fig. 3E); propodeal spine in profile distinctly more than three times longer than its base and not tapering apically; subpetiolar process absent (Fig. 3F) Crematogaster ghoneimi

9

 * Antennal scapes when laid back from their insertions just reach posterior margin of head in full-face view
 * Antennal scapes when laid back from their insertions clearly surpassing posterior margin of head in full-face view

10

 * Unicolorous brown species; clypeus smooth; anterior half of head in full-face view longitudinally striated, ground surface between striae smooth; posterior half of head smooth, general appearance of head shining (Fig. 3A) Crematogaster senegalensis
 * Bicolored species, head, mesosoma, petiole, postpetiole and appendages brown or red-brown, gaster golden yellow; clypeus longitudinally striated; anterior half of head in full-face view finely longitudinally striated, grown surface between striae and posterior half of head finely densely punctate; general appearance of head dull (Fig. 3B) Crematogaster flaviventris

11

 * Mesonotum in profile without a small tubercle close to promesonotal suture
 * Mesonotum in profile with a small tubercle close to promesonotal suture

12

 * Whole cephalic surface finely, densely longitudinally striated and dull; head in full-face view with antennal scapes surpassing posterior margin of head byapproximate length of the three funicular segments together; propodeal spines long and acute, more than twice longer than bases; mesonotum in profile feebly convex; subpetiolar process well developed; mesosomal hairs numerous, five on promesonotum, two on pronotum, and a single pair on the propodeum (Figs. 3C, 3D) Crematogaster melanogaster
 * Anterior half of cephalic surface superficially striated, posterior half smooth and shining; head in full-face view with antennal scapes surpassing posterior margin of head by ca. thickness of the first funicular segment; propodeal spines shorter and blunt, ca. 1.5× longer than bases; mesonotum in profile strongly convex; subpetiolar process absent; mesosomal hairs restricted to a single pair on pronotum (FigS. 3E, 3F) Crematogaster auberti

13

 * Cephalic surface and clypeus completely finely densely longitudinally striated Crematogaster striaticeps
 * Anterior half of cephalic surface or at least area in front of eyes and clypeus longitudinally striated

14

 * Promesonotum with at least four pairs of suberect hairs; petiole in dorsal view with pointed anterior corners; first gastral tergite with several pairs of hairs (ca. 7 pairs) Crematogaster oasium
 * Promesonotum with a single pair of hairs or without hairs; petiole in dorsal view with rounded anterior corners; hairs on first gastral tergites rare, restricted to few pairs on posterior margin of the tergite

15

 * Petiole in dorsal view with concave anterior margin; promesonotum and mesonotum dorsum unsculptured (Fig. 4A) Crematogaster antaris
 * Petiole in dorsal view with a straight anterior margin; promesonotum and mesonotum dorsum distinctly longitudinally striated (Fig. 4B)

16

 * Postpetiole approx. twice broader than long in dorsal view; color black-brown or dark brown (Fig. 4C) Crematogaster laestrygon
 * Postpetiole little broader than long in dorsal view; color red-brown (Fig. 4D) Crematogaster jehovae