Simopone wilburi Weber, 2012

Bolton, Barry & Fisher, Brian L., 2012, Taxonomy of the cerapachyine ant genera Simopone Forel, Vicinopone gen. n. and Tanipone gen. n. (Hymenoptera: Formicidae) 3283, Zootaxa 3283 (1), pp. 1-101 : 40-42

Simopone wilburi Weber stat. rev.

( Figs 31–33 )

Simopone wilburi Weber, 1949: 7 , figs 6, 7. Holotype worker, DEMOCRATIC REPUBLIC OF CONGO (“B. Congo ” on data label): Ituri F., Beni-Irumu, 17 mi. north of Beni, 24.ii.1948, #2119 (N.A. Weber) (AMNH) [examined]. Stat. rev. [Previously junior synonym of schoutedeni: Brown, 1975: 36 .]

WORKER. HL 0.94–1.08, HW 0.64–0.75, SL 0.32–0.40, EL 0.34–0.40, PW 0.47–0.55, AIIW 0.48–0.55, AIIL 0.49–0.58, AIIIW 0.57–0.67, AIIIL 0.58–0.72, WL 1.14–1.36, MFL 0.58–0.69, CI 67–71, SI 50–54, EL/HW 0.51– 0.53, EP 0.86–1.00, AIIW/AIIL 0.93–0.98, AIIIW/AIIIL 0.94–1.00 (7 measured).

With head in full-face view the outlines of the outer margins of the eyes conspicuously project beyond the outlines of the sides of the head through at least the median third of their lengths. ES 0.30–0.35 and width of head across broadest part of eyes 0.67–0.76; minimum distance between eyes 0.28–0.36. Frontal carinae extend back to level of anterior margins of eyes and are weakly divergent posteriorly. Cephalic dorsum with scattered broad, shallow punctures. Ground sculpture is present between the eyes, organised into roughly longitudinal fine costulae or striolae between the punctures; ground sculpture fades out behind the level of the eyes. Leading edge of scape with a few setae, inclined toward the scape apex. Sides of head below and behind eyes with projecting short setae, inclined anteriorly. Cephalic dorsum with numerous short, curved setae and with a few pairs of longer setae present; longest setae occur on the frontal carinae and above the eye. Ventral surface of head with short setae. Mesosoma in dorsal view narrowest across the mesonotum (maximum width 0.46–0.54), broadest across the propodeum (maximum width 0.51–0.62). Anterior margin of pronotum weakly, finely carinate. Propodeum with a fine weak carina between dorsum and declivity. Entire dorsum of mesosoma with widely spaced broad, shallow punctures, somewhat less dense on pronotum than elsewhere. Mesopleuron with a few punctures and a distinct transverse sulcus. Propodeal declivity smooth except for a narrow band of disorganised superficial sculpture immediately below the dorsal carina. In profile, dorsal surfaces of mesosoma and all abdominal tergites with numerous posteriorly curved setae. Standing setae are sparsely present on middle and hind tibiae. AII (petiole) in dorsal view with a weak transverse carina both anteriorly and posteriorly, the sides convex and divergent posteriorly, broadest just behind the midlength; the width across the anterior margin is less than across the posterior margin. Dorsum of AII with large, shallow punctures whose diameters are usually equal to or greater than the distances that separate them. On tergite of AIII the punctures are of similar size and distribution. AII and AIII both usually slightly longer than broad, AIV distinctly broader than long (width 0.68–0.78, length 0.56–0.73; AIVW/AIVL 1.07–1.20). Head capsule and body black; scapes and funiculi dull yellow; femora brown; tibiae and tarsi yellow.

QUEEN (dealate gyne; not previously described). Answers the description of the worker. About the same size as the largest worker but with a full complement of flight sclerites. HL 1.08, HW 0.74, SL 0.39, EL 0.37, PW 0.56, AIIW 0.54, AIIL 0.58, AIIIW 0.70, AIIIL 0.75, WL 1.44, MFL 0.70, CI 69, SI 53, EL/HW 0.50, EP 0.90, AIIW/ AIIL 0.93, AIIIW/AIIIL 0.93; mesoscutum maximum width 0.64, maximum length 0.40.

Closely related to vepres but separated by the characters in the key. In addition, in the little material available, EL/HW tends to be a little lower in vepres . S. wilburi is known to be size-variable in the worker, an observation that may apply throughout the schoutedeni group. A short series of six wilburi workers from near Minvoul, in Gabon (CASC) produced both the largest and smallest examples of the species noted above (e.g. HW 0.94–1.08), the latter the same size as the holotype; all others fell between these extremes, but of course it is not known if these include the actual minimum and maximum sizes possible. See also the notes under schoutedeni .

Brown (1975) synonymised wilburi under schoutedeni , and indeed the two do seem very closely related. But direct comparison of the holotypes of the two shows distinct differences in the size of the eyes and in the shape of AII. These features were consistent in all specimens assigned to wilburi here, and consistently different from the holotype of schoutedeni , still the only known specimen of that species. S. wilburi is therefore removed from synonymy and reinstated at species-rank.

Material examined. Cameroun: Minko Meyos, S of Yaoundé (J.L. Mercier). Gabon: Prov. Ogooué-Maritime, Res. Monts Doudou, NW Doussala (B.L. Fisher); Prov. Woleu-Ntem, ESE Minvoul (B.L. Fisher), two short series. Democratic Republic of Congo: Ituri For., Beni-Irumu, N of Beni (N.A. Weber).

Figures

FIGURES 31–33. Lateral, full face and dorsal view of body. Simopone wilburi worker CASENT0004516.