Glomeris monostriata Golovatch & Mauriès, 2009

Golovatch, Sergei, Mauriès, Jean-Paul, Akkari, Nesrine, Stoev, Pavel & Geoffroy, Jean-Jacques, 2009, The millipede genus Glomeris Latreille, 1802 (Diplopoda, Glomerida, Glomeridae) in North Africa, ZooKeys 12 (12), pp. 47-86 : 54-56

Glomeris monostriata Golovatch & Mauriès , sp. n.

urn:lsid:zoobank.org:act:B6C89F7D-F1BF-44C1-AE72-15016BC6F8D2

Fig. 2

Type material. Libya, Cyrenaica , Ayn Dabusia, cave near Al Qubbah, 280 m, 32°50’00.9″N, 22°16’49.6″E (WGS84), 8.IV.2008, leg. S. Taiti, holotype ♁ (MNHN CC 166), paratypes: 1 ♁, 2 ♀ (MNHN CC 166), 1 ♁, 1 ♀ (MSNF), 1 ♁, 1 ♀ (ZMUM) .

Name: To emphasize the collum and the thoracic shield each being crossed by only a single stria.

Diagnosis: Differs from all congeners except G. albida Mauriès & Vicente, 1978 in being troglomorphic, coupled with only a single stria crossing the collum and thoracic shield; differs from G. albida in the evidently bifid horns and a lower central lobe of the telopod syncoxite.

Description: Length of adults of both sexes (unextended, alcohol material) ranging between 8.0 and 9.0 mm, width between 3.0 and 3.2 mm, up to ca 11 and 3.5 mm, respectively (extended animals); body broadest at thoracic shield. Holotype (unextended) ca 8.2 mm long and 3.2 mm wide. Coloration entirely pallid.

Head usual, transverse; Tömösváry’s organ transversely oval, slightly less extended transversely than in G. troglokabyliana sp. n.; antennae long, antennomere 6 longest, 2.4-2.5 times longer than wide; distance between antennal sockets 1.95 times greater than socket diameter; ocelli 4+1, rather convex, but transparent and thus poorly visible.

Collum with one (anterior) transverse stria.

Thoracic shield with a narrow hyposchism reaching the caudal tergal contour ( Fig. 2A ); two transverse striae, of which the one starting well in front of the schism crosses the entire dorsum, the other, starting just above the schism, is abbreviated ( Fig. 2A ).

Tergum 3 relatively narrowly ( Fig. 2A ) and tergum 4 broadly rounded laterally. Tergal pilosity and mid-dorsal sinuosity missing. Pygidium usually with a completely regularly rounded caudal margin, only rarely extremely faintly sinuated medially at margin.

♁ leg 17 ( Fig. 2B ) with a low, slightly irregularly rounded, outer coxal lobe; telopodite 4-segmented.

♁ leg 18 ( Fig. 2C ) with an ogival syncoxital notch; telopodite 4-segmented.

Telopods ( Figs 2D, E ) with a low, regularly rounded, bare, central syncoxital lobe flanked by two setose and evidently bifid horns. Prefemur micropapillate distolaterally. Femur with a large caudomedial outgrowth, subquadrate at base. Tibia with a tuber- culiform caudomedial outgrowth and a strong caudolateral seta near base. Tarsus quite narrowly rounded apically.

Remarks: This species is the first glomeridan to be recorded in Libya and, given that it is troglobitic, may represent a relictual element.

In general, the condition of having just one stria, rather than two, crossing the collum is extremely rare in Glomeris species. The only other congener showing this condition that we are aware of is G. albida Mauriès & Vicente, 1978 , a troglobite from Málaga, Spain ( Mauriès and Vicente, 1978). Both these species are evidently regressive, apparently in response to cavernicoly. Similarly, G. albida also demonstrates two striae on the thoracic shield, only the anteriormost of which crosses the dorsum. In addition, both these species are pallid, of about the same size, with the same number (5) of ocelli and the same proportions (L/D 2.5) of antennomere 6, and both are devoid of tergal or pygidial sinuosity. The main differences concern the shape of the telopod syncoxite, being strongly marked in the bifid tip of the horns and the relatively low and regularly rounded central lobe in G. monostriata sp. n.

Even more regressive appears to be G. dionysii ( Strasser, 1961) , a troglobite from Sicily, Italy, which totally lacks striae on the collum ( Strasser 1961).

Based on the narrow tergum 3, G. monostriata sp. n. can readily be attributed to the “ Stenopleuromeris ” type.

Figures

Figure 2. Glomeris monostriata sp. n., ♁ paratype; A, thoracic shield and tergum 3, lateral view; B, leg 17; C, leg 18; D, E, leg 19 (telopod), caudal and frontal views, respectively. – Scale bar: 0.2 mm (B-E); drawn not to scale (A).