Oxidus gracilis (C.L. Koch, 1847 )

Vohland, Katrin & Hamer, Michelle, 2013, A review of the millipedes (Diplopoda) of Namibia, with identification keys and descriptions of two new genera and five new species, African Invertebrates 54 (1), pp. 251-251 : 259-261

Oxidus gracilis (C.L. Koch, 1847)

Figs 8–11

Fontaria gracilis: C.L. Koch 1847: 142 ; 1863: 51.

Polydesmus gracilis: Porat 1872: 9 ; Karsch 1880: 78.

Paradesmus dasys Bollman, 1887: 619 .

Paradesmus gracilis: Latzel 1895 a: 116 ; 1985 b: 104; Verhoeff 1891: 126; Schubart 1926: 64.

Kepolydesmus sontus Chamberlin, 1910: 247 .

Orthomorpha gracilis: Pocock 1895: 354 .

Oxidus gracilis: Cook 1911: 628 ; Mikhaljova 1993: 30; 1998: 59; Mikhaljova & Nefediev 2003: 83; Hoffman 1999: 436; Tajovský 2001: 18; Enghoff et al. 2004: 39; Geoffroy & Golovatch 2004: 20; Korsόs 2004: 24; Chen et al. 2006: 265.

Orthomorpha (Kalorthomorpha) gracilis: Attems 1914 b: 191 ; 1937 a: 82; Lawrence 1953: 344; Schubart 1966: 16.

Diagnosis: Four tufts of setae on sternite 5. Solenomere with broadened tip, intertwined with median tibiotarsal process ( Fig. 8). Apical tibiotarsal process tapered and acute, basal tibiotarsal process sheath-like.

Description:

Size: Width of male 1.3 mm.

Colour: Brown, antennomeres darker distad except for a whitish tip. Anterior and lateral border of collum as well as peritremata (calluses) dirty yellow. Prozonites distally dirty white, anterior with dark border. Legs and venter light brown.

Head: Epicranial suture distinct, antenna long, reaching back to 4 th segment, antennomere 2>6=3>4=5>1>7; antennomeres 5+6 with microsensilla.

Collum: Broadly rounded.

Tergites and sternites: Metatergal sulcus deep and finely rifled. Surface porous, prozonite and metazonite separated by a constriction bearing small ridges. Sternites broad, sternite 5 and 6 with four setose fields ( Fig. 11). Paraterga slightly protruding from 5 th segment onwards, more expressed posterior to mid-body, on segments 15 (in some cases 17) to 19 acute. Pleurotergal ridges weak, only in segments 2–4 distinct, distad only small swellings. Epiproct slightly bilobed ( Fig. 10).

Legs: Tibia of legs with small setose projections.

Gonopods: As in diagnosis.

Material examined: NAMIBIA: 3♂ 3♀ Oranjemund [28°33'06"S 16°25'35"E, 24 m], 25–27.ii.1972, LGC, M. Sa & M.-L. Penrith ( SMN 21679 ) ( NMNW) .

Distribution: This species, which probably originated in East or Southeast Asia, is distributed worldwide, and is known to occur in hothouses. It was first recorded from South Africa in 1914 (Attems 1914), and is now recorded for the first time from Namibia.