Ommatoiulus malleatus, Akkari, Nesrine & Voigtländer, Karin, 2007

Akkari, Nesrine & Voigtländer, Karin, 2007, Ommatoiulus malleatus n. sp., a new Tunisian millipede, with notes on the punicus species group of Ommatoiulus (Diplopoda, Julidae), Zootaxa 1400, pp. 59-68 : 60-63

Ommatoiulus malleatus n. sp.

Figs 1–5

Material examined: Holotype: Ichkeul National Park (North Tunisia), 24.09.2005, 1 ɗ, leg. N. Akkari.

Paratypes: 14 ɗ (all investigated for external characteristics, 9 for gonopods), 16 Ψ (10 investigated), 3 juveniles (not investigated), same location and date, leg. N. Akkari.

Deposition: State Museum of Natural History Görlitz, Germany (SMNG): the whole type series (Catalog no. 13657) with exception of 2 ɗ and 2 Ψ deposited in the Muséum National d’Histoire Naturelle de Paris, France (MNHN) and 2 ɗ, 2 Ψ deposited in the Faculty of Sciences of Tunis, Tunisia (FST). Further material from the type locality: 0 7.10.0 5, 1 ɗ, 2 f and 6 juveniles, leg. N. Akkari deposited in SMNG.

Locus typicus: Ichkeul National Park, plain of Mateur, governorate of Bizerte, Northern Tunisia.

Latitude: 37° 9' 18"N (37.155°), longitude: 9° 39' 37"E (9.661°).

Altitude: 11 m.

Bioclimatic zone: sub humid with warm winters.

Soil: Outcrops mainly composed of shales and limestone.

Vegetation: Tree groups of Olea europea and maquis of Pistacia lentiscus with Phillyria angustifolia , Smilax aspersa and Juniperus phoenicia .

Habitat: Under stones.

Etymology: The species name refers to the special hammer­like structure of the mesomerite process in the posterior gonopod.

Description: Body length: 15.8–28.3 mm (measured laterally along the line of ozopores); body vertical diameter 1.6–2.8 mm (at the 15th body ring); ratio length/width: 9.9–10.1/1; females longer and broader, body more compact than in males ( Table 1 ).

Color: Grey­reddish brown on a yellowish background. Head with reddish brown apex, darker medially, showing 2 larger oval (lateral) and 2 smaller (central) brighter and circular spots between the antennae; mouthparts lighter. Antennae dark chocolate brown. Collum with darker spots at the anterior and posterior borders (from above), all edges pale. Prozonite with numerous rounded to oval reddish­brown spots on darker brown background; mid­laterally with black irregular stains above the ozopores. Dorsally, posterior portion of the prozonite pale, surrounding quite large upturned triangular stain crossing the suture and pointing towards the border of the following trunk segment. Bright pale­yellowish metazonites finely striated showing slightly thickened mid­dorsal lines in continuation with the mid­dorsal peaks. Dark brown pre­anal ring, paler on the edge and showing a yellowish projection ending with a bright hyaline structure. Ventral scale blackish. Anal valves dark brown, paler on the border. Legs pale reddish with darker border.

Head and collum: Head with 21–35 clearly visible hexagonal ocelli in 6–8 horizontal rows, occipital furrow distinct and narrow, no occipital setae; collum with 0, seldom 1–3 fine lateral striae.

Prozonite and metazonite: Prozonite finely pinstriped; ventrally with sturdier and narrower striation. Metazonite with longitudinal fine and complete striation and moderately spaced striae. At the level of ozopores, ratio length of metazonite / width of the space between striae: 3.5–5/1. Ozopores in metazonites, their diameter as large as their distance from the suture along the whole body. The suture complete, rectilinear or rarely slightly curved at the ozopore level.

Telson: Pre­anal ring with a pointed triangular tail slightly upturned, with very small hyaline structure and showing 2–5 pairs of setae on the top and 2 lateral setae at each side; ventral scale with 2–4 pairs of setae; each anal valve with 1–5 setae on disc, 6–10 (mostly 7) long submarginal setae and 20–34 half as long densely set marginal setae.

Secondary sexual characters of males

Head: Stipes of mandible with well­developed rounded lobe ( Fig. 1 ).

Body ring 7: Pleuro­tergal lobe cone­like with an upturned edge.

Legs: 1st pair of legs modified into a hook­like structure ( Fig. 2 ); postfemoral pads on legs from the 2nd pair up to those of the 30th–35th podous rings; tibial pads from the 2nd pair up to those of the 33rd–40th podous rings, pads best developed in anterior part of trunk.

Gonopods: Anterior gonopod: promerite ( Fig. 3–4 ) simple, voluminous, half as wide as long [length: width = 1: 0.47 (0.44–0.49)] with parallel margins and a posterior concavity; divided in a median ( Fig. 3 , m) and lateral lobe ( Fig. 3 , l) by a curved notch ( Fig. 3 , n) showing a little bump ( Fig. 3 , p2).

Large, but individually variable number of very small setae scattered in different arrangements over the posterior surface (sparsely over the whole surface or more or less concentrated and located close to the internal edge). 1–6 (mostly 3) rigid setae placed in a vertical row close to the internal edge of the promerite. Number of the large setae with individual variations between the left and the right side of the gonopods ( Fig. 3–4 ).

In posterior view, the median lobe with wave­shaped apex and two orthogonally oriented bumps, one median rounded bump ( Fig. 3 , mrb) and one lateral pointed one ( Fig. 3 , lpb). Two small rounded protuberances ( Fig. 3 , p1) laying in the concavity of the wave. The lateral lobe large, rounded with many striations marginally. The internal apical side of the promerite with 2–3 irregular shaped folds ( Fig. 3 , fd) reaching the lateral lobe by a deep curve.

Posterior gonopod ( Fig. 5 ) with three branches: The anterior process (mesomerite; Fig. 5 , ms) long and presenting a characteristic hammer­like structure on the apex. The posterolateral process (paracoxite; Fig. 5 , px) simple and long, slightly curved on the top. The posteromesal process (opisthomerite; Fig. 5 , op) deeply divided into 3 parts at its distal third: The anterior part a hyaline sheet ( Fig. 5 , hy) with jagged edges; the middle part (solenomerite; Fig. 5 , s) a straight stem, inclined mesad and containing the seminal groove; the posterior part large, lobed and jagged on the top with many serrations.

The anterior and posterior gonopods are the same length.

Figures

FIGURES 1 – 5. Ommatoiulus malleatus n. sp., ♂, paratypes: 1. head and collum (lateral); 2. first right leg (lateral); 3. right promerite (anterior), fd folds, l lateral lobe, lpb lateral pointed bump, m median lobe, mrb median rounded bump, n notch, p 1 median protuberances, p 2 lateral protuberance; 4. left promerite (posterior); 5. posterior gonopod (posterior), hy hyaline sheet, ms mesomerite, op opisthomerite, px paracoxite, s solenomerite.

Tables

TABLE 1. General characters of males and females in O. malleatus n. sp.

	males	females
Trunk
body length (mm)	15. 8–25.2	18.9–28.3
body vertical diameter (mm)	1.6–2.1	1.9–2.8
ratio length/width	9.9–12/1	10–10.1/1
number of podous rings	38–45	42–45
number of apodous rings	1–3	2–3
Telson (number of setae)
pre­anal ring (at the tip)	2–3	2–5
pre­anal ring (lateral on each side)	2	2
ventral scale	2–3	3–4
anal valves (on disc)	2–5	1–4
anal valves (submarginal and marginal)	6–8 and 20–34	7–10 and 24–32
Ocelli
number	21–35	27–35
number of rows	6–8	6–7