Cylindroiulus distinctus ( Lucas, 1846 )

Read, Helen J., 2005, A revision of the Cylindroiulus distinctus Lucas group from north Africa, with descriptions of six new species (Diplopoda, Julida, Julidae), Journal of Natural History 39 (18), pp. 1491-1532 : 1494-1497

Cylindroiulus distinctus ( Lucas, 1846)

( Figures 1–7 )

Iulus distinctus Lucas 1846: 286 .

Iulus (Phalloiulus) distinctus: Brölemann 1897: 266 .

Cylindroiulus (Phalloiulus) distinctus: Brölemann 1931: 125 .

Cylindroiulus (Phalloiulus) distinctus: Schubart 1963 (but as there are no illustrations it is only presumed to be the correct species).

Material studied. Algeria: „ (in poor condition as previously a dry specimen, gonopods absent), Type de la collection Lucas , Algérie, coll. Brölemann 1902 ( MNP); 1 „, 2♀, (Type A) Algérie, Lucas, Brölemann vid. (same sample as above?) ( MNP); 1 „ (gonopods absent), Petit Atlas , 1600 m, Blida, No. CCCLXVI, April 1896, Brölemann det. ( MNP); 2♀, details as above ( MNP); 1 „ (illustrated), 7 juvenile „, 1♀, G. Kabylie, Forêt d’Akfadou, Azerou n’Taghat, 1300 m, 3 May 1983, Osella leg. ( ZMUC); 2 „? (one illustrated), 2♀, Sott. (Kabylie), 1000 m, 9 June 1980, F. T. d’Akfadou, G. Osella ded., 1983 ( ZMUC); 1 „, 4 juvenile „, 4♀, Bois de Boulogne près Alger, H. Gauthier, 14 December 1930 ( MNP); 9♀, details as above ( MNP); 1 „, Sittirt 11.4.19.267 ( BMNH) .

Total material examined. 39 (8 „).

Diagnosis. A large dark species with a long accessory claw and clear, not reduced eyes. Gonopods with the four major parts of the opisthomerite (brachite, solenomere, projections X and Y) roughly even in size and all directed laterally.

Descriptiυe notes. Body length 35–41.5 mm („) to 43 mm (♀); maximum vertical diameter 2.5–2.6 mm („) to 3.5 mm (♀); number of podous body rings 50–51 („), 47–52 (♀).

Colour. Head chestnut brown, telson , anal valves and apodous rings dark chocolate brown. Main trunk of body with dark brown metazonae and paler (in younger specimens) or glaucous (older specimens) prozonae. With very thin black mid-dorsal line. Sometimes darker dorsally.

Eyes. Clearly readable, not reduced. Males with 10–11 rows of ocelli, females up to 11.

Telson . Usually lacking any dorsal projection but a slight protuberance in mature males ( Figure 1 ). Preanal ring with 10–15 pairs of setae usually arranged evenly around it. Ventral scale with two to three pairs of setae. Anal valves with eight to 19 pairs of setae mostly marginal, a few sometimes forming a double row.

Oυerall body shape. Anterior constriction slight, posterior attenuation present in younger specimens. Metazonal vaulting slight, striae close and even.

Legs. Legs 0.61 X body height in male, accessory claw surpassing claw by 125% of the claw length.

Male sexual characters

Mandibular stipites. With well-developed lobes ( Figure 2 ).

First pair of legs. Small sharp hooks. Gonopods ( Figures 3–7 ). Promerite long and narrow, coming to long point apically and widest subapically. In anterior view with apparent ‘‘window’’ (cf. Cylindroiulus perforatus ; Read 1989a) caused by thin region where mesomerite fits. Flagellum normal. Mesomerite shorter than promerite, slim, hooked apically. Paracoxal process absent, paracoxal rim very high. Opisthomerite large and complex with many processes. Solenomere broad, rounded apically, whitish in colour (in both males examined). Extra projection (X) dorsally in same antero-posterior plane of almost equal size and clearly visible in lateral and posterior view. Large phylacum projecting from the posterior surface and running the whole length of opisthomerite. Large brachite, hood-like in shape when seen from lateral view, straightended apically in posterior view, with additional tooth meso-apically (not on Brölemann’s figures) and larger additional projection (Y) most clearly seen in lateral view and in viewing the posterior gonopods from the anterior side.

Female sexual characters

Operculum wide and flat topped.

Comments

The gonopods of the specimens described above clearly represent the same species as Figures 22–25 of Brölemann (1897). The segment numbers agree with those of Brölemann but the body lengths he gave of 29–30 mm for the males and maximum of 33 mm for the females seem a bit low in comparison to measurements made here.

Pocock (nd) lists Diploiulus distinctus (Lucas) from Monaco with a note that ‘‘this Algerian species is new to the European fauna’’. The specimens ( BM 1892.9.1.266–271) were re-examined, dissected and discovered to be Cylindroiulus limitaneus (Brölemann 1905) .

Figures

Figures 1–7. Male Cylindroiulus distinctus from Algeria, G. Kabylie, Forêt d’Akfadou, Azerou n’Taghat. (1) Telson and anal valves (V, ventral scale). (2) Expanded mandibular stipites. (3) Right gonopods from lateral view. (4) Right gonopods from mesal view. (5) Right gonopods from posterior view. (6) Right gonopods from anterior view. (7) Posterior gonopods in anterior view. Scale bars: 1 mm (1, 2); 0.1 mm (3–7).

Figures 21–25. Gonopods of male C. gauthieri from Algeria, El Kseur, F. t. d’Akfadou. (21) Lateral view. (22) Mesal view. (23) Posterior view. (24) Anterior view. (25) Anterior (and slightly ventral) view of posterior gonopods. Scale bars: 0.1 mm.