Atalopharetra clarkei, Mesibov, Robert, 2005

Mesibov, Robert, 2005, (Diplopoda: Polydesmida: Dalodesmidae) from Tasmania, Australia, Zootaxa 1034, pp. 21-42 : 31-34

Atalopharetra clarkei n. sp.

Figs. 1 B, 2B, 3C, 3G, 3I, 10, 11; map Fig. 15

Holotype: Male, Cyclops Pot (cave IB­57), Ida Bay, Tasmania, approx. 43°28’S 146°51’E, 26.x.1985, S. Eberhard, on wet shaft wall of Pitch 4, 80 m below surface, field code IB57­ 1, QVM 23:45949.

Paratypes: 1 male, 1 female, Mystery Creek Cave (cave IB­10), Ida Bay, approx. 43°27’S 146°51’E, 20.i.1985, S. Eberhard, mudbank slope above final siphon near end of cave, field code IB10­9, AM KS91435 (formerly QVM 23:12180); 2 males, Milk Run (cave IB­38), Ida Bay, approx. 43°29’S 146°51’E, 22.viii.1985, S. Eberhard, on cave wall near bottom of cave, field code IB38­3, QVM 23:12170; 3 males, 1 female, details as for holotype, QVM 23:12073; 2 males, 2 females, Arthurs Folly (cave IB­110), Ida Bay, approx. 43°27’S 146°52’E, 20.xi.1986, A. Clarke and S. Eberhard, in groups on mudbank beside stream (Deep Zone), Clarke field code 8611­6, Eberhard field code IB110­2, QVM 23:12078; 2 males, 2 females, Exit Cave (cave IB­14), Ida Bay, approx. 43°29’S 146°51’E, 7.v.1988, S. Eberhard, mudbanks beside stream in Mystery Creek Cave passage, field code IB14­2, QVM 23:12083; 3 males, 1 female, Loons Cave (cave IB­2/3), Ida Bay, approx. 43°27’S 146°52’E, 10.v.1989, S. Eberhard & J. Jackson, mudbanks beside stream well into cave, field code IB2­3, QVM 23:12249; 1 male and 1 female in copula, Arthurs Folly (cave IB­110), Ida Bay, approx. 43°27’S 146°52’E, 24.vi.1990, A. Clarke, near “Y” junction on RHS wall, 1 m above drop, 500 m into cave, field code 690­01, QVM 23:41667; 1 male, 1 female, same details but cave floor beside stream, beyond “Y” junction, 700 m into cave, field code 690­02, QVM 23:41668; 2 males, 1 stadium VII male, Exit Cave (cave IB­14), Ida Bay, approx. 43°30’S 146°50’E, 18.i.1993, A. Clarke, soil bank beside stream in Base Camp Tributary, field code 193­110, QVM 23:41652.

Diagnosis: Pigmentation faint or absent; paranota on posterior segments reduced but with pointed, protruding posterior corner; telopodite with short, stout, recumbent solenomere and large, laminar, hood­like distal process divided into two slightly overlapping portions; limbus with pointed elements.

Description: Male ca. 20 mm long; segment 12 height ca. 1.3 mm, width ca. 1.6 mm. Body colour in alcohol off­white; brown colouration (cuticle staining by defensive secretion?) variably deep along posterior margin of metazonites, on paranotal margins, in patches on some legs and laterally on sternites. Cuticle not brittle; defensive secretion not strongly smelling. Head almost flat in front, sparsely setose with longer setae on vertex; antennae ( Fig. 3 C) long, slender, separated by about twice a socket diameter, sockets slightly impressed ventrally and laterally; antennomere 6 the widest, antennomere lengths decreasing in order 2, (3,6), (4,5). Collum slightly wider than head, semicircular in dorsal view, with marginal seta near posterior corner, smooth dorsally and with 3 transverse rows of sparse setae. Segment 2 slightly wider than collum, segments 3–5 increasingly but only slightly wider than 2, segments 5–18 more or less equal in width. Segments 2–18 smooth dorsally with 3 transverse rows of sparse setae. Paranota on segment 2 ( Fig. 3 I) welldeveloped, concave upwards; margin higher than collum edge, with 4 marginal teeth, the posterior 3 armed with a stout seta. Paranota on segments 3 and 4 with margins increasingly higher than on segment 2 and with 3 marginal teeth each armed with stout seta. Metazonites of segments 5–18 trapezoidal in dorsal view ( Fig. 1 B) with reduced paranota; paranotal margins without teeth, with 3–4 setae along posterior half, level in lateral view; paranota slightly concave upwards. Limbus (visible at bottom of Fig. 2 B) composed of tapering, sharply pointed elements. Ozopore opening dorsolaterally on rounded swelling at posterior corner of paranotum. Preanal ring sparsely setose; epiproct with truncated tip, extending slightly past anal valves; hypoproct trapezoidal. Spiracles small, on diplosegments with anterior spiracle above anterior leg and posterior spiracle above and slightly anterior to posterior leg; spiracle interior protruding (spiracles visible in Fig. 2 B). Sternites ( Fig. 2 B) very much longer than wide, with anterior leg bases well­separated from posterior leg bases. Anterior legs somewhat swollen with dorsally convex prefemur ( Fig. 3 G), but all legs slender; tarsus longer than femur and both podomeres much longer than prefemur, postfemur or tibia; claw long and slender; anterior legs with dense “brush” setae with slightly expanded tips on prefemur, femur and postfemur, and a few sphaerotrichomes on tibia and tarsus. Leg 2 coxa with prominent gonopore on slight ventromedial swelling. Leg 7 bases well­separated to accommodate retracted gonopods, leg 6 bases close together. Gonopod aperture ovoid, about three­quarters the width of segment 7 prozonite, the posterior and posterolateral portions of the rim considerably extended. Gonopod coxae tapering distally, lightly joined mediodistally, medial apical extension small, cannula prominent. Telopodites ( Figs. 10 , 11 ) short, broad, just reaching leg 7 bases when retracted. Telopodite somewhat flattened anteroposteriorly near base, expanding at about one­third the telopodite height into a thin­walled hood concave posteromedially, the hood divided distally into two portions, the lateral portion slightly overlapping the medial portion, the latter with a finely fringed margin; sparse, long setae on posterior surface of telopodite to base of hood. Solenomere cylindrical with blunt, rounded tip, arising on anteromedial surface of telopodite near base, extending distally before bending laterally to enter base of hood, the distal portion recumbent on finely fringed portion of inner surface of hood ( Fig. 10 , right). Male and female about equal in size and almost identical in overall appearance, but anterior legs of female not swollen; posterior rim of epigynum elevated medially as rounded, tooth­like projection; cyphopods not examined.

Distribution and habitat: Known only from caves near Ida Bay in southern Tasmania ( Fig. 15 ).

Etymology: In honour of Arthur Clarke, Tasmanian cave zoologist.

Figures

FIGURE 1. Dorsal views of midbody segments of females of (A) Atalopharetra sp. (unidentified female of A. bashfordi n. sp. or A. johnsi n. sp.), QVM 23: 15120, (B) A. clarkei n. sp., QVM 23: 41668, and (C) A. eberhardi n. sp., QVM 23: 12623. Scale bars = 0.5 mm, anterior towards top.

FIGURE 2. Ventral views of sternites on segment 14 of males of (A) Atalopharetra bashfordi n. sp., QVM 23: 40499, (B) A. clarkei n. sp., QVM 23: 12073, and (C) A. eberhardi n. sp., QVM 23: 12620. Scale bars = 0.5 mm, anterior towards top.

FIGURE 3. Atalopharetra johnsi n. sp., QVM 23: 15088 (A, E), A. bashfordi n. sp., QVM 23: 40500 (B, F), A. clarkei n. sp., QVM 23: 12073 (C, G, I), and A. eberhardi n. sp., QVM 23: 12620 (D, H). Antenna (A – D), leg 6 (E – H) and dorsal outline of segment 2 (I) of males. Scale bar = 1 mm.

FIGURE 10. Atalopharetra clarkei n. sp., QVM 23: 12073. Posterior SEM view of gonopods in situ, scale bar = 0.5 mm (left) and close­up of left gonopod solenomere tip, scale bar = 0.1 mm (right).

FIGURE 11. Atalopharetra clarkei n. sp., QVM 23: 12078. Mesal (left) and posterolateral (right) views of right gonopod telopodite. Setation not shown; scale bar = 0.25 mm.

FIGURE 15. Localities for Atalopharetra clarkei n. sp. (squares indicated with “ C ”), A. eberhardi n. sp. (squares indicated with “ E ”), and unidentified Atalopharetra sp. (triangles; see Appendix for details). Inset shows location of main map.