Ginglymodesmus tasmanianus Mesibov, 2005, n. sp.
Creators: name: Mesibov, Robert
Publisher: name: Zenodo
Year: 2005
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Diplopoda
Polydesmida
Dalodesmidae
Ginglymodesmus
Ginglymodesmus tasmanianus

description: Ginglymodesmus tasmanianus n. sp.
Figs. 1, 2 A, 3A, 3D, 3E, 4; map Fig. 5
Holotype: Male, Argent River, Tasmania, CP681690 (41°49’06”S 145°24’48”E), 330 m, 21.i.1992, R. Mesibov, QVM 23:46124.
Paratypes: 2 males, S of Foam Creek, CP255871 (41°38’50”S 144°54’21”E), 10 m, 1.vi.1993, R. Mesibov, QVM 23:46127; male, same details, AM KS92528; 4 males, Library Creek, DQ239419 (41°10’09”S 146°05’39”E), 20 m, 23.iv.1995, R. Mesibov and T. Moule, QVM 23:46130.
Other material examined: 2 males, 5 km S of Renison Bell, approx. CP680670 (41°50’S 145°24’E), 180 m, 1.v.1987, N. Platnick, R. Raven and T. Churchill, AMNH; male, same details, QVM 23:46120; male, Anthony Road, approx. CP854680 (41°50’S 145°37’E), 840 m, 21.iv.1989, NRCP personnel, QVM 23:46121; male, Waratah, CQ806092 (41°27’30”S 145°34’18”E), 630 m, 26.x.1991, R. Mesibov, QVM 23:46122; 3 males, same details but 27.x.1991, QVM 23:46123; male, N of Rocky Creek, CP245920 (41°36’10”S 144°53’43”E), 10 m, 2.v.1993, R. Mesibov, QVM 23:46125; male, Italian River, CQ174058 (41°28’37”S 144°48’52”E), <10 m, 2.v.1993, R. Mesibov, QVM 23:46126; male, N of Pieman Head, CP261860 (41°39’26”S 144°54’46”E), 10 m, 1.vi.1993, R. Mesibov, QVM 23:46128; male, near Dead End Den cave, approx. CP972929 (41°36”S 145°46’E), 330 m, 10.vii.1994, R. Mesibov, QVM 23:46129; 3 males, Black Bog Creek, DP113962 (41°34’46”S 145°56’14”E), 860 m, 3.vii.1997, R. Mesibov, QVM 23:46131; male, Southwell River, CP975922 (41°36’49”S 145°46’16”E), 750 m, pitfall emptied 17.iii.2000, C. Carr, QVM 23:46132.
Diagnosis. Differing from G. penelopae and G. sumac in bearing a prominent rounded process arising midway along the distal section of the telopodite on the anteromesal surface; from G. penelopae in the proximal telopodite section extending laterally on the anterior side of its apex; and from G. s u m a c in bearing a pointed process midway along the distal telopodite section on the posterior rather than anterior side.
Description: Males (Fig. 1 A) 5­6 mm long with head and 19 body segments. Wellcoloured specimens in alcohol uniformly light tan with white head and legs, sometimes with pinkish tinge to antennomeres.
Head moderately setose with antennal sockets well­impressed laterally and ventrally. Antennae separated by ca. 1.25x a socket diameter; antennomere lengths decreasing in the order (2,6), 3, (4,5), 7, antennomere 6 much wider than others (Fig. 3 D).
Collum moderately setose, semicircular in dorsal outline, narrower than head and tergite 2. Tergite 2 with lateral margin much lower than collum corner, somewhat lower than tergite 3 margin (Fig. 1 A); anterior margin projecting slightly forward; no pit on underside. Widths of tergites 2 and 4 about equal, tergite 3 narrower and shorter. Paranota placed high on body (Fig. 1 A), with rounded anterior “shoulders”, well­defined margins and no posterior projections (Fig. 4 A). Tergites smooth with three transverse rows of small setae and a few small setae on lateral and posterior margins (Fig. 4 A). Limbus (Fig. 4 B) composed of tab­like, irregularly toothed elements. Sternites longer than wide with transverse impression somewhat deeper than longitudinal impression. Preanal segment moderately setose; epiproct with rounded tip, extending slightly past anal valves; hypoproct trapezoidal.
Anterior legs (Fig. 3 E) with dorsally much­swollen prefemur, slightly swollen femur; tarsus straight, podomere lengths decreasing in the order tarsus, (prefemur, femur), (postfemur, tibia). Sphaerotrichomes on tarsus and tibia, one or two on postfemur; sphaerotrichome shafts tapering to points. Dense “brush” setae on prefemur and femur, tapering to points. Gonopore opening in small conical projection distomedially on leg 2 coxa.
Ozopores on segments 5, 7, 9, 10, 12, 13, 15­18, opening laterally near rear of paranota above margin (Fig. 4 A). Spiracles simple pits, on diplosegments opening just above anterior leg and above and slightly forward of posterior leg.
Gonopod aperture between one­third and one­half the width of the segment 7 prozonite; aperture slightly reniform (concave anteriorly), the posterior margin extended towards each of the leg 9 bases to form small “embayments” in the aperture, and the posterolateral margin extending ventrally on either side as a bluntly pointed process.
Gonocoxae ovoid, partly fused along midline, bearing a few setae and entirely contained within gonopod cavity. In specimens with extended gonopods (Fig. 1), the lower portion of the telopodite also hidden in cavity.
Telopodite (Figs. 1, 2 A, 3A) reaching leg 3 when retracted, divided into base, proximal section and distal section with approximate relative lengths 1:5:4; distal section pivoting anteroposteriorly around tip of proximal section. Base more or less oblong, wider than long with rounded corners, lightly joined medially to contralateral base, a few long, coarse setae on posterodistal surface and numerous fine setae on posterobasal surface. Proximal telopodite section extending from lateral and distal surface of base, gently curved posteriorly, free of setae, extending anterolaterally at its end as a lamina and terminating distally in a small tooth. Distal telopodite section continuous basally with a shallow cuticular “basin” on the posterior surface of the proximal section (Fig. 2 A), the two structures resembling a disarticulated ball­and­socket joint. Distal section more or less straight and coaxial with proximal section, free of setae, divided at about three­quarters its length into a slender posterior branch (solenomere) curving posteriorly and bearing the prostatic groove, and a slightly longer anterior branch with a somewhat obovate, anteroposteriorly flattened tip. Distal section also bearing large, tooth­like, distally pointing process arising at about half the section length on posterolateral surface, terminating proximal to solenomere base, and a rounded, mesolaterally flattened structure arising just distal to base of tooth­like process on opposite (anteromesal) surface of distal section. Prostatic groove entering base on mesal side, turning abruptly laterally then distally to run without interruption along proximal and distal sections and terminating at tip of solenomere.
Distribution and habitat: In coastal scrub, wet eucalypt forest and cool temperate rainforest over ca. 3500 km 2 in northwest Tasmania (Fig. 5), from sea level to at least 860 m.
Etymology: For Tasmania, to which Ginglymodesmus appears to be endemic.
Remarks: Across the range of this species there is a little variation in the shape of the rounded extension on the anteromesal surface of the distal telopodite section, and in the shape of the tip of the anterior terminal branch.
description: Published as part of Mesibov, Robert, 2005, dae) from Tasmania with a pseudo­articulated gonopod telopodite, pp. 39-49 in Zootaxa 1064 on pages 42-46, DOI: 10.5281/zenodo.170198