Mixophyes coggeri, Mahony, Michael, Donnellan, Stephen C., Richards, Stephen J. & Mcdonald, Keith, 2006

Mahony, Michael, Donnellan, Stephen C., Richards, Stephen J. & Mcdonald, Keith, 2006, Species boundaries among barred river frogs, Mixophyes (Anura: Myobatrachidae) in north­eastern Australia, with descriptions of two new species, Zootaxa 1228, pp. 35-60 : 55-58

Mixophyes coggeri new species (group II)

( Fig. 6B )

Holotype

QM J79551 , an adult male from Pilgrim Sands, Cape Tribulation, Queensland, Australia, 16° 04’ S, 145° 28’ E, collected by M. Mahony, R. Knowles, and S. Donnellan on 30 December 1987.

Other material examined: see Appendix 1.

Diagnosis

Mixophyes coggeri differs from other members of the M. schevilli species complex by its possession of a discontinuously linear series of large irregularly shaped blotches along the mid­dorsal region and by the presence on the posterior surface of thighs of 0–9 large (1–11 mm) irregularly shaped pale botches, each bordered by a dark margin. It differs further from M. schevilli only by possessing a larger head.

Description of Holotype

Head flattened, slightly broader than long (HL/HW = 0.86); snout prominent, gently rounded when viewed from above and in profile. Nostrils more lateral than superior, distance from snout approximately equal to distance from eye (SN/EN = 1.06); distance between eye and naris approximately equal to internarial span (EN/IN = 0.95); canthus rostralis well defined and straight; loreal region slightly concave below canthus rostralis, becoming convex towards upper lip. Eye relatively small, diameter slightly larger than eye to naris distance (EY/EN = 1.06); pupil vertical when constricted. Tympanum large, conspicuous, and oval with long axis slightly tilted towards eye. Tympanum diameter less than eye length (TY/E = 0.73). Vomerine teeth relatively long straight rows directed from anterior margin of choanae to midline between choanae. Tongue approximately rectangular, not notched posteriorly. Fingers long, slender, and unwebbed. Subarticular and palmar tubercules prominent, especially palmar tubercule at base of digit one; brown glandular nuptial pad on inner palmar tubercule and entire length of first digit except terminal disc. Relative lengths of fingers 3>4>1>2; hind limbs moderately long (TL/SVL = 0.61). Toes webbed between fifth and fourth toes with exception of distal phalanx of fourth toe, which is fringed with web. Webbing between fourth and third toes with the exception of distal two phalanges of fourth toe, which is fringed with web. Webbing between third and second toe with exception of distal phalanx of third toe that is fringed with web. Webbing between second and first toes midway along distal phalanx of first toe to the joint of distal phalanx of second toe. Subarticular tubercules present on first and second toes only; inner metatarsal tubercule prominent with well developed outer edge; relative lengths of toes 4>5>3>2>1. Dorsum and venter smooth.

Dimensions of holotype (in mm): SVL, 89.5; TL, 55; HL, 35; HW, 41; EN, 9.5; IN, 10; EY, 10; IO, 18; TY, 7; A, 20; F3, 26; F3D, 1.5; T4, 45; T4D, 2; MT, 6.

Color in preservative: Dorsum dark chocolate brown. Broad, dark brown, mid­dorsal stripe originates anteriorly as an inter­orbital bar and extends along mid­line of dorsum to mid­sacral region, its lateral margins uneven and edged with black. Mid­dorsal stripe with some small internal paler patches. Small very dark flecks on dorsum lateral to mid­dorsal stripe. Dark lateral headstripe commences at nares and extends posteriorly over and around posterior margin of tympanum. Lateral edge of all limbs scalloped with very dark, approximately triangular, patches. Dorsal surface of hindlimbs and arms dark brown with distinct narrow darker brown transverse bars. Posterior surface of thigh speckled with fine irregular pattern and with 0–9 large (1–11 mm) irregular pale blotches per thigh, each bordered by dark margin. Palmar surfaces of feet and hands dark brown.

Var ia t io n: Males are 64–93 mm and females from 74–104 mm SVL ( Table 3 ). Hind limbs are long (TL/SVL = 0.61 ± 0.04, range = 0.45–0.70). Head length less than head width (HL/HW = 0.86 ± 0.04, range = 0.75–0.94), and eye to naris distance usually less than internarial span (EN/IN = 0.91 ± 0.08, range = 0.75–1.08). Mid­dorsal region with continuous, very broad stripe that has internal light patches, or a linear series of very large dark blotches. At least some margins of stripe and blotches finely edged in black or white. Remainder of dorsal surface usually with few to many small to large blotches. Dark lateral headstripe extends posteriorly beyond supratympanic fold, reaching to above axilla, width variable. Dark bars on upper surface of limbs with fine black margins, very narrow to moderately broad. Only 0–9 large pale blotches (1–11 mm diameter) on posterior surface of each thigh. Blotches tend to be concentrated on distal section of thigh towards ventral edge and sometimes extend onto ventral surface at knee. Blotches always bordered by a dark margin that varies in intensity. Ventral surfaces immaculate except that the chin has a dusky margin in 44% of specimens.

The single specimen of M. coggeri from Mt Lewis (ABTC 51086), as mentioned previously, has a mtDNA haplotype that is inconsistent with its morphological phenotype and allozyme profile. Allozymes, morphology and meristics are consistent with M. coggeri , but mtDNA is consistent with M. carbinensis . At present, we are not able to satisfactorily explain these data but suggest two possibilities. First, there may be some introgression between M. carbinensis and M. coggeri on the Carbine Tableland. If there is introgression, then the specimen must be a late generation backcross to have the mtDNA of M. carbinensis and the allozyme profile of M. coggeri at nine loci. Alternatively, the specimen was mislabelled. However, we did not find another specimen with the opposing combination of mtDNA and allozyme/morphology that the Carbine Tableland specimen could have been swapped with. Furthermore, these taxa are morphologically the most distinct of the three WTWHA Mixophyes . More samples from the Carbine Tableland are needed to clarify the situation.

Color in life: Dorsal surfaces of body and limbs vary from light fawn to rich copper brown or dark brown. Mid­dorsal stripe, dorsal patches, patches on sides of face, and bars on limbs darker brown or copper­brown than ground color. Center of dorsal and facial patches lighter than margins, which, in some individuals, are bordered by thin cream line. Lateral head stripe black, bordered by fine cream or fawn line sharply demarcated against the black stripe but diffuses into ground color. Tympanum darker than ground color, not bordered by lighter line. Upper lip immaculate or with small brown blotches. Small black patches occur immediately below and adjacent to eye. Lateral triangular patch that expands from external nostril to front of jaw dark brown or black towards margin with a more diffuse lighter brown center. Iris dark brown. Brown of dorsal surface merges laterally with lighter ventral coloration. Posterior surface of thigh dark brown to grey with irregularly shaped cream or off­white blotches, each with darker margin. Sides of limbs with roughly triangular, dark brown to black patches. Ventral surfaces white with a lemonyellow flush. Chin slightly darker lemon yellow with diffuse grey wash around margins and towards articulation of the jaw. Ventral surfaces of limbs off­white. Fingers and toes same color as dorsum but webbing between the toes black. In males, nuptial pad grey to brown.

Etymology

Named for Professor Harold George Cogger, former deputy director of the Australian Museum, for his sustained, significant, and wide­ranging contributions to herpetology on a global scale.

Distribution

Widely distributed in the WTWHA of northeastern Queensland from lowland and upland areas in the north to the Paluma Range in the south.

Figures

FIGURES 6 A – C: Holotypes of Mixophyes species; A, M. carbinensis sp. nov. (QM J 79552), B, M. coggeri sp. nov. (QM J 79551), and C, M. schevilli (MCZ 18150).