Paredrodesmus monticolus, Mesibov, Robert, 2003

Mesibov, Robert, 2003, Two new and unusual genera of millipedes (Diplopoda: Polydesmida) from Tasmania, Australia, Zootaxa 368, pp. 1-32 : 16-17

Paredrodesmus monticolus n. sp.

Figs. 6 , 10 , 11 , map Fig. 12 D

Holotype: Male, Butlers Gorge, DP401203 (42°16’01”S, 146°16’25”E), 720m, 18.ii.1994, R. Mesibov, QVM 23 :25484.

Paratypes: 3 males, details as for holotype, AM KS86292 ; 2 males, details as for holotype, QVM 23 :41154; 4 males, Little Florentine River , DN525683 (42°44’10”S, 146°25’10”E), 440m, 13.iii.1986, R. Bashford, QVM 23 :41148, pitfall, one specimen in fragments.

Other material examined: 23 males. See Appendix for details.

Diagnosis: Distinguished from other Paredrodesmus by the unique form of the gonopod.

Description: As for the genus. Males 10–12 mm long, 0.9–1.0 mm in maximum vertical diameter. In alcohol, well­coloured adults are pale with reddish mottling on distal anntennomeres and metazonites, notably around ozopores. Antennal bases separated by ca. 1.25 times a base diameter, antennomere 6 about one and a quarter times the width of 5. Legpairs 6 and 7 with a wide gap between coxae, legpair 5 with a narrower gap, legpair 4 with a small gap; flexed gonopods reach nearly to legpair 4. Genital opening on leg 2 coxa on a prominent mesal projection ( Fig. 6 A). Gonopod aperture with rear margin slightly raised in the middle. Telopodites ( Fig. 10 ) closely pressed together but not fused, the contact surfaces flat, the outer surface rounded. Telopodite base small with a few short and long setae; the distal portion of the telopodite ( Fig. 11 ) arising medially, first bending cephalad, then curving smoothly caudad before expanding into a broad tip with a slightly rounded distal surface. Prostatic groove running along the mesal surface of the telopodite before turning laterad across the telopodite tip and ending in a very small, bluntly pointed solenomerite situated nearly in the middle of the tip. Arising from the anteromesal corner of the tip is a short, blunt process armed with 10–15 short, laterally directed setae; a cluster of ca. 20 variably long, peg­like structures, directed proximad and slightly laterad, is attached to the posterolateral corner of the tip.

Distribution and habitat: In well­rotted litter, humus and richly organic soil over ca. 11 0 0 0 km 2 in central Tasmania from 150 m to at least 1250 m, mainly in wet eucalypt forest and Nothofagus rainforest ( Fig. 12 D). Overlaps in range with P. bicalcar , co­occurs with P. taurulus . An uncommon species.

Etymology: Latin monticolus , mountain­dwelling, adjective. This species has mainly been collected at higher elevations.

Figures

FIGURE 6. Antennae and legs of Paredrodesmus spp. males. All drawings to same scale, apical cones and setation not shown. (A) Leg 2 of (left to right) P. aceriodendron n. sp., QVM 23: 41165, P. australis n. sp., QVM 23: 41167, P. b i c a l c a r n. sp., QVM 23: 41178, P. monticolus n. sp., QVM 23: 41155, P. p u r p u re u s n. sp., QVM 23: 41524 and P. taurulus n. sp., QVM 23: 41132; (B) antennae of (left) P. b i c a l c a r n. sp., QVM 23: 41178 and (right) P. aceriodendron n. sp., QVM 23: 41165; (C) leg 9 of P. purpureus n. sp., QVM 23: 41524; (D) leg 3 and sternal projection of P. taurulus n. sp., QVM 23: 41132; (E) leg 1 (left, posterior view) and leg 3 and sternal projection (right) of P. b i c a l ­ car n. sp., QVM 23: 41178.

FIGURE 10. SEM view of Paredrodesmus gonopods in situ, anterior to left. (Left) P. monticolus n. sp., QVM 23: 41158; scale bar = 0.5 mm. (Right) P. purpureus n. sp., QVM 23: 41525; scale bar = 0.45 mm, ‘ s’ = solenomerite.

FIGURE 11. Lateral view of left gonopod telopodite of Paredrodesmus monticolus n. sp., QVM 23: 41155. Basal setation not shown; dashed line marks course of prostatic groove.

FIGURE 12. Distributions in Tasmania of Paredrodesmus spp. (A) P. aceriodendron n. sp. (large squares) and unidentified Paredrodesmus females and juveniles (small squares); (B) P. taurulus n. sp. (squares) and P. australis n. sp. (crosses); (C) P. b i c a l c a r n. sp. (squares); (D) P. monticolus n. sp. (crosses) and P. purpureus n. sp. (squares).