Uperoleia saxatilis, Catullo, Renee A., Doughty, Paul, Roberts, Dale & Keogh, Scott, 2011

Catullo, Renee A., Doughty, Paul, Roberts, Dale & Keogh, Scott, 2011, Multi-locus phylogeny and taxonomic revision of Uperoleia toadlets (Anura: Myobatrachidae) from the western arid zone of Australia, with a description of a new species, Zootaxa 2902, pp. 1-43 : 23-25

Uperoleia saxatilis sp. nov.

Pilbara Toadlet

Holotype. WAMR 162877, a calling male collected at Turee Creek (23º20’37.6”S, 118º1’16.6”E), Western Australia, in May 2006 by P. Doughty, C. Stevenson, and P.G. Kendrick ( Fig. 9 ).

Paratypes. There are 10 paratypes, 4 adult males and 6 adult females: WAM R 110883, a gravid female collected 36.8 km SSE of Pannawonica (21º56’28.7”S, 116º27’14.0”E), Western Australia, on 16 March 2005 by R.J. Teale; WAM R135086, a gravid female collected at Hamersley Gorge, Karijini National Park (22º15’S, 118º0’E), Western Australia, on 28 August 1996 by S.J. Reynolds; WAM R135639, a female collected at Pinga Creek Crossing (21º28’59.9”S, 118º39’0.0”E), Western Australia, on 16 February 1999 by B. Maryan and J. Smith; WAM R140012, a male collected at Millstream Chichester National Park (21º10’52.7”S, 117º3’28.1”E), Western Australia, on 12 September 1999 by Ecologia; WAM R145561, a gravid female collected 80 km S of Port Hedland (21º0’36.0”S, 118º42’0.0”E), Western Australia, on 3 May 2001 by R.J. Teale; WAM R154550, a gravid female collected at Wheelarra Hill (23º23’21.8”S, 120º9’41.0”E), Western Australia, on 12 February 2004 by M. Ladyman; WAM R154764, a male collected at Brockman Ridge (23º19’9.8”S, 119º57’11.9”E), Western Australia, on 5 April 2004 by J. Fraser; WAM R156614, a male collected at the Woodie Woodie Minesite (21º38’58.9”S, 121º14’17.2”E), Western Australia, on 11 June 2005 by M. Peterson; WAM R156222, a gravid female collected at Cattle Gorge (20º36’11.9”S, 120º15’51.1”E), Western Australia, on 17 December 2004 by M. Ladyman; and WAM R166206, a male collected 10 km S of Nullagine (21º57’16.9”S, 120º7’35.04”E) Western Australia, on 11 September 2006 by M. Peterson and K. George.

Diagnosis. Distinguished from all other Uperoleia by a combination of large body size (males 20.9–33.0 mm, females 27.4–36.6 mm SUL) with short limbs (TL/SUL 0.35±0.02 [0.31–0.39]), narrow snout (EN/IN 1.40±0.12 [1.18–1.66]), absence of maxillary teeth, extensively exposed frontoparietal fontanelle, brown skin with darker markings, red femoral patches when present, moderately large hypertrophied parotoid glands, moderately developed inguinal and coccygeal glands which are restricted to the rear portion of the body. Toes extensively webbed to second proximal tubercle, and elongate, thin, and large inner and outer metatarsal tubercles. A low-pitched squelch as an advertisement call.

Description. Moderately large body size, squat, thick and rotund. Head is small, thin in depth with slightly protruding eyes. When viewed laterally, slightly sloping snout and slightly rounded tip; when viewed from above, the sides of the snout slope in strongly and come to a short slightly rounded tip. Canthus rostralis moderately defined with gradually rounded edge; loreal region sloping and slightly convex. Moderate rounded medial projection (synthesis of mentomeckelian bones) that matches notch on upper jaw. Nostrils directed upwards; nares with slight rim. Anterior corner of eye covered by flap of skin, which is usually darkly pigmented; at dorsal terminus the skin overlaps the skin of the brow above the eye. Posterior edge of brow does not project over side of head side of head. Tympana covered by skin and parotoid glands. Tongue oval and elongate. Maxillary and vomerine teeth absent. Frontoparietal fontanelle extensively exposed. EN larger than IN (EN/IN 1.40±0.12 [1.18–1.66]).

Arms and hands thickly built. Arms are short (ArmL/SUL 0.39±0.09 [0.34–0.37]) and the fingers are poorly fringed and unwebbed. Finger length 3>4>2>1. Tubercles under fingers moderately developed; one on first and second, two on third and fourth. Palmar tubercles moderately developed. Moderately developed outer palmar tubercle on distal portion of wrist. Nuptial pad of males on inner portion of first finger (beginning halfway down finger), extending to base of wrist (¼ along forearm) and slightly encroaching on palmar surface.

Legs moderately short (TL/SUL 0.35±0.02 [0.31–0.39]) and of thick build. Toe length 4>3>5>2>1. Tubercles under toes moderately developed and conical; one on first and second, two on third and fifth, three on fourth. Toes moderately long, webbed almost to second proximal tubercle on fourth toe, and moderately to strongly fringed. Webbing highly reduced between fourth and fifth toes. Large, slightly spatulate inner metatarsal tubercle, oriented along fifth toe. Outer metatarsal tubercle spatulate and oriented perpendicular to foot.

Skin rough with large scattered tubercles on dorsum, with a raised mid-vertebral stripe. Ventral surface slightly granular. Cloacal flap present, moderately fimbriated in males and strongly fimbriated in large females. Parotoid gland extensively developed, starting from just behind eye and extending up 1/3 of body length; inguinal and coccygeal glands moderately developed and restricted to rear portion of body. Scattered glandular tubercles between inguinal and parotoid glands. Mandibular gland moderately developed and disrupted.

Coloration. Dorsal ground color is a dark brown. Blackish patches cover the dorsal surface. Red tubercles often forming a dorsolateral stripe extending from the snout to approximately between the middle of the parotoid glands. Reddish tubercles may be present on sides and upper limbs. Glands are pigmented in shades of red varying from light pink to crimson (Figs. 7 & 9). Reddish femoral coloration when present, although frequently absent. Ventral surface a pale off-white. Background pigment usually absent on upper inner thigh, with scattered white tubercles. Males have a darkly pigmented chin.

Holotype measurements. (in mm) SUL–30.1, ArmL–12.6, TL–10.7, FL–18.1, IO–4.6, EyeL–2.8, EN–2.4, IN–1.53.

Advertisement call. Figure 6 f and 6g and Table 5 summarize the main features of the call. The holotype was recorded producing two calls; a long squelch of 19–24 pulses, and a short squelch of 15–19 pulses. The long call is much more common on nights of high calling activity.

Habitat. Specimens have been collected while calling from the banks of rocky creeks.

Distribution. Extensive sampling has shown this species to be restricted to the rocky Pilbara Craton. Apparently adapted to rocky landscapes, this species does not occur in any of the sandy regions surrounding the Pilbara, including the Roebourne Plain (Fig. 8d).

Etymology. The Latin word saxatilis is an adjective meaning ‘associated with rocks’ referring to the distribution of this species on the rocky Pilbara craton.

Comparisons with other species. This species can be distinguished from U. glandulosa and U. russelli by absence of red to golden glands connecting along the sides, possessing a darker ground coloration and many small dark dorsal blotches (versus larger, often interconnecting blotches). In addition, U. saxatilis differs from the sympatric U. glandulosa by having more extensive webbing between the toes (to between first and second or to second proximal tubercle versus to first proximal tubercle) and a squelch (versus a click) as an advertisement call. Near the edges of the Pilbara craton U. micromeles may also closely occur; from this species U. saxatilis can be distinguished by narrower snout (EN/IN 1.18–1.58 versus 0.70–0.88), more extensive webbing (to between first and second or to second proximal tubercle versus basal) and lacking fine white tubercles on sides of snout and above eyes. Uperoleia saxatilis is most similar morphologically to its sister species U. talpa and is compared extensively in the U. talpa description above.

Figures

FIGURE 6. Oscillographs and spectrograms of (a) U. glandulosa, U. russelli (b) long call and (c) short call, U. talpa (d) long call and (e) short call, and U. saxatilis sp. nov. (f) long call and (g) short call.

FIGURE 9. Photos in life (dorsolateral and dorsal views) and after preservation (ventral view) of U. saxatilis sp. nov. holotype (WAM R 162877) from Turee Creek, Western Australia. Photos by P. Doughty.