Orthorhachis pallida Jeekel, 1985

Mesibov, Robert, 2008, The millipede genera Gephyrodesmus Jeekel, 1983 and Orthorhachis Jeekel, 1985 in southeastern Australia, a new Lissodesmus Chamberlin, 1920 from Victoria, and observations on male leg setae, spinnerets and metatergite sculpture (Diplopoda: Polydesmida: Dalodesmidae), Zootaxa 1790, pp. 1-52 : 37-38

Orthorhachis pallida Jeekel, 1985

Figs.1E, 2C, 5C, 6D, 24; map Fig. 32B

Orthorhachis pallida Jeekel, 1985:52 , Figs. 1–3; 2006:73. Shelley et al., 2000:118.

Holotype: Male. Bunya Mountains National Park, Koonawarra near Mt Kiangarow, 27 km WSW of Tarong, Qld, 23 October 1980, C.A.W. Jeekel & A.M. Jeekel-Rijvers, along nature track in dry type rainforest, under logs. Possibly in Zoological Museum, Amsterdam; not examined.

Paratypes: None.

Other material: In QM: 2 males, 1 female, Ravensbourne National Park , Qld, Cedar Block Track, 26 November 1973, K. R. McDonald, S83683 ; 3 males, 1 female, 1 stadium 7 female, Bunya Mountains , Qld, 1974–1975, G. & S. Monteith, rainforest pitfall 19, S83686 ; 1 male, same details, S83687 ; 6 males, 1 female, 1 stadium 7 male, same details but Mt Cabinet via Conondale, Qld, pitfall 29B, S83684 ; 1 male, same details but Booloumba Creek via Conondale, Qld, pitfall 12, S83685 ; 1 male, Archookora via Nanango, Qld, 580 m, 1975–76, G. & S. Monteith, rainforest, pitfall 62, S83688 ; 1 male, Lower Neurum Creek , Mt Mee State Forest, Qld, 1977–78, G. Monteith, rainforest, pitfall 90, S83689 ; 3 males, 4 females, Burtons Well campground, Bunya Mountains, Qld, 11 January 1988, P.M. Johns, woodpile, S83690 ; 1 male, Bare Rock , 2 km N of Mt Cordeaux, Qld, 31 December 1993 – 20 February 1994, G. Monteith, pitfalls, S83691 .

Diagnosis: Gonopod telopodite in lateral or medial view with constriction at about one-third telopodite height, and with apex abruptly bending posteriorly at branching point.

Description: As for the genus; see Jeekel (1985) for a detailed description of the O. pallida holotype. Male and female approximate measurements: length 18–24 mm, midbody prozonite diameter 1.6–2.1 mm, midbody width across paranota 2.4–3.2 mm. Body slightly discoloured in material examined, light brown. Antennal sockets separated by 2X a socket diameter. Antennae slender, relative lengths of antennomeres 2>(3,6)>(4,5). Collum D-shaped, as wide as head and narrower than tergite 2. Metatergite sculpture indistinct, Pattern A ( Fig. 6D). Paranota with anterior margin slightly convex, lateral margin more or less parallel to long axis of body. Legs slender, leg 6 tarsus 1.5X as long as femur ( Fig. 5C). Brush setae with forked tips ( Fig. 1E). Spinnerets not enclosed by low walls on epiproct ( Fig. 2C).

Gonopod aperture ovoid, slightly wider than long, about one-third the width of the ring 7 prozonite. Gonopod ( Fig. 24) as described by Jeekel (1985), but all males examined, including those from the type locality, also have a small, finger-like projection arising at about two-thirds telopodite height on the lateral side, curving basally and slightly posteriorly.

Female not significantly larger than male, legs not swollen. Genital aperture with posterior margin slightly raised in middle in wide inverted V, bent slightly anteriorly. Cyphopods not examined.

Distribution: So far known from ca. 8000 km 2 in far southeastern Queensland, from the Bunya Mountains east to the Conondale Range, and south almost to Cunninghams Gap, ca. 25 km north of the New South Wales Border ( Fig. 32B). Possibly parapatric with O. yabbra near Cunninghams Gap.

Remarks: Overall size varies considerably in O. pallida as circumscribed here. The smallest specimens are from the Bunya Mountains (type locality, and furthest inland) and the largest are from sites closer to the coast. The gonopod telopodite in larger males has a more distinct basally directed lobe on the medial process, and there is less swelling on the lateral side of the telopodite and a sharper concavity on the medial side.