Ommatoiulus kefi Akkari & Enghoff

Akkari, Nesrine, Cheung, David Koon-Bong, Enghoff, Henrik & Stoev, Pavel, 2013, Revolving SEM images visualising 3 D taxonomic characters: application to six species of the millipede genus Ommatoiulus Latzel, 1884, with description of seven new species and an interactive key to the Tunisian members of the genus (Diplopoda, Julida, Julidae), ZooKeys 328, pp. 5-45 : 13-15

Ommatoiulus kefi Akkari & Enghoff sp. n. Figs 14-19

Material.

Holotype: ♂, W Tunisia, El Kef Governorate, 13 km S El Kef, 22.iv.1981, Bianchi & Moretti leg. (MSNB).

Diagnosis.

Differing from all congeners by having a tri-lobate distal part of promerite and a bifurcated apical part of mesomerite, the latter divided in two short oppositely directed processes.

Etymology.

Named after El Kef city, the type locality of the species.

Description.

Male: L: 26 mm, H: 2.7 mm, 53 PR+1 AR+T. General colour alternating whitish and blackish with a thin black mid-dorsal line. Head brown, lighter on the frontal part, with yellowish spots at antennal level, labral zone yellowish, becoming brighter at the margin, antennae brownish. Prozonites pale grey, dorsally scarcely sputtered with black; metazonites anteriorly dark, with a blackish background and a line of light brown spots below ozopores; legs whitish. Telson: anal valves and preanal ring blackish, paler towards caudal projection, subanal scale yellowish. Prozonites with scattered oblique striae; metazonites with regular striation becoming dense laterally; suture complete and rectilinear; ozopores small, rounded and located in metazonites, well apart from the suture. Anal valves with numerous submarginal and marginal setae and ca. 1-2 setae on the surface; subanal scale triangular, blunt and setose; preanal ring protruding in a caudal projection, with ca. 3+3 setae and a small hyaline process on the tip.

Male sexual characters. Mandibular stipites expanded in rounded posterior-ventral lobes, first pair of legs hook-shaped, remaining legs with postfemoral and tibial pads.

Gonopods. Promerite (Fig. 14) in posterior view subrectangular, mesal ridge (M) fairly broad, distally narrowing and protruding into a pointed apical lobe (al); apical margin protruding in a curved median lobe (me) pointing laterad and a shorter broad lateral lobe (lb); the three apical lobes separated by two rounded incisions; lateral margin almost rectilinear. Remnant of telopodite (T) ovoid, located at mid-length of promerite.

Posterior gonopod (Figs 15-19): Mesomerite (Ms) broadest at the base, distally protruding in a uniformly broad process, apically splitting into two short and curved processes, pointing in opposite directions (m1, m2) (Figs 16, 17, 19); solenomerite (S) broad at the base, slightly narrowing at mid-length and showing a triangular process (pr) separated from the rest of the processes by a rounded (n) (Figs 17, 19), apical part of the solenomerite complex with a broad lamella (al1) extended latero-mesad, downturned and marginally furrowed (Fig. 16). Seminal groove (g) running from the fovea (F) at the base of solenomerite up to a slender and short conical process (ds) emerging on top of the median part of the apical lamella and pointing anteriad (Figs 15, 17). Paracoxite (Px) stout, with smooth margins, emerging from a broad rounded coxite (Co) (Figs 18, 19).

Distribution.

Semi-arid bioclimatic zone in western Tunisia; hitherto known only from the type locality near El Kef city.

Comments.

We have examined three females (MSNB) collected from the same locality but could not assign them with certainty to Ommatoiulus kefi as they show a different colour pattern.