Three New Species of Ctenotus (Reptilia: Sauria: Scincidae) from the Kimberley Region of Western Australia, with Comments On
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Records of the Western Australian Museum 25: 181–199 (2009). Three new species of Ctenotus (Reptilia: Sauria: Scincidae) from the Kimberley region of Western Australia, with comments on the status of Ctenotus decaneurus yampiensis Paul Horner Museum and Art Gallery of the Northern Territory, GPO Box 4646, Darwin, Northern Territory 0801, Australia. E-mail: [email protected] Abstract – Three new species of Ctenotus Storr, 1964 (Reptilia: Sauria: Scinci- dae), C. halysis sp. nov., C. mesotes sp. nov. and C. vagus sp. nov. are described. Previously confused with C. decaneurus Storr, 1970 or C. alacer Storr, 1970, C. halysis sp. nov. and C. vagus sp. nov. are members of the C. atlas species com- plex. Ctenotus mesotes sp. nov. was previously confused with C. tantillus Storr, 1975 and is a member of the C. schomburgkii species complex. The new taxa are terrestrial, occurring in woodland habitats on sandy soils in the Kimberley region of Western Australia and are distinguished from congeners by combi- nations of body patterns, mensural and meristic characteristics. Comments are provided on the taxonomic status of C. yampiensis Storr, 1975 which is considered, as in the original description, a subspecies of C. decaneurus. Re- descriptions of C. d. decaneurus and C. d. yampiensis are provided. Keywords – Ctenotus alacer, decaneurus, yampiensis, halysis, mesotes, tantillus, vagus, morphology, new species, Kimberley region, Western Australia INTRODUCTION by combinations of size, scale characteristics, body Ctenotus Storr, 1964 is the most species-rich genus colour and patterns. of scincid lizards in Australia, with almost 100 taxa recognised (Horner 2007; Wilson and Swan 2008). Examination of a series of Ctenotus specimens, They are distributed throughout the Australian from the Kimberley region of Western Australia, continent, with one species also occurring in identified three forms with unusual body southern New Guinea. patterns. Comparison of these to known species of similar appearance, investigating morphology With about 49 species recorded (Wilson and and nomenclatural histories, resulted in their Swan 2008), the Australian arid zone (up to 70% recognition as undescribed taxa. of the continent) is the primary centre of Ctenotus diversity. However it is becoming increasingly This paper, on morphological and distributional apparent that diversity may be just as great in grounds, describes those three taxa as new Australia’s wet-dry tropical savanna regions, where species and examines the taxonomic status of approximately 36 known species occur in what is populations referred to C. decaneurus Storr, 1970 about 15% of the continent. Throughout their range and C. yampiensis Storr, 1975. Comparisons are Ctenotus species are commonly sympatric (pers. made between the new taxa and those species with obs.), particularly in parts of the Great Victoria which they could be confused and features of their Desert in Western Australian where up to seven habitats are described, if known. species can be found in a single, Triodia dominated, sand plain (Pianka 1986). MATERIALS AND METHODS Typically diurnal, Ctenotus occupy a diverse A series of atypical Ctenotus specimens, held array of habitats, ranging from arid deserts to in collections of the Museum and Art Gallery of temperate woodlands. Many species exhibit a high the Northern Territory (NTM) and the Western degree of habitat specificity and may have very Australian Museum (WAM), were examined and restricted distributions (Horner 1995). Sharing a assigned to three undescribed species. A detailed basic body plan, Ctenotus species are differentiated morphometric and meristic analysis was made 182 P. Horner Table 1 Summary of mensural and meristic variables for Ctenotus alacer, C. d. decaneurus, C. d. yampiensis and C. haly- sis sp. nov. Presented are mean (± 1 SD), mode (meristics only) and range in parentheses. C. alacer C. d. decaneurus C. d. yampiensis C. halysis sp. nov. Character (n=10) (n=28) (n=4) (n=10) midbody scale rows 29.8 ± 1.03, 30 (28–32) 25.5 ± 1.29, 26 (24–28) 30.5 ± 1.29, 0 (29–32) 29.0 ± 1.15, 30 (27–30) paravertebral scales 67.9 ± 4.93, 70 (60–75) 58.5 ± 5.10, 55 (50–67) 59.0 ± 2.00, 60 (56–60) 59.6 ± 4.22, 59 (52–67) nuchal scales 7.7 ± 1.16, 9 (6–9) 8.1 ± 1.78, 8 (2–10) 7.0 ± 1.83, (5–9) 8.6 ± 1.07, 9 (6–10) supralabial scales 8.3 ± 0.48, 8 (8–9) 7.6 ± 0.49, 8 (7–8) 8.0 ± 0.00, 8 (8) 7.8 ± 0.42, 8 (7–8) infralabial scales 7.1 ± 0.32, 7 (7–8) 6.6 ± 0.49, 7 (6–7) 7.0 ± 0.00, 7 (7) 7.0 ± 0.00, 7 (7) supraciliary scales 7.1 ± 0.32, 7 (7–8) 8.2 ± 0.53, 8 (7–9) 8.0 ± 0.00, 8 (8) 8.0 ± 0.67, 8 (7–9) ciliary scales 10.0 ± 0.67, 10 (9–11) 9.4 ± 0.64, 9 (9–11) 10.7 ± 0.96, 10 (10–12) 10.8 ± 0.92, 10 (10–12) ear lobules 3.9 ± 0.74, 4 (3–5) 4.1 ± 0.63, 4 (3–5) 4.2 ± 0.50, 4 (4–5) 4.9 ± 0.74, 5 (4–6) subdigital lamellae (4th finger) 14.3 ± 0.67, 14 (13–15) 12.7 ± 1.04, 12 (11–15) 14.0 ± 0.82, 14 (13–15) 14.0 ± 0.82, 14 (13–15) supradigital lamellae (4th finger) 10.3 ± 0.48, 10 (10–11) 10.0 ± 0.66, 10 (9–11) 10.0 ± 0.00, 10 (10) 10.2 ± 0.42, 10 (10–11) subdigital lamellae (4th toe) 26.6 ± 2.07, 29 (23–29) 20.7 ± 1.69, 21 (18–23) 21.0 ± 1.41, 22 (19–22) 21.7 ± 1.06, 21 (20–23) supradigital lamellae (4th toe) 17.0 ± 1.41, 17 (15–20) 15.0 ± 1.19, 15 (13–17) 14.7 ± 1.26, 15 (13–16) 16.0 ± 1.25, 15 (15–18) snout-vent length (mm) 57.5 ± 5.32 (47.6–67.4) 45.1 ± 4.82 (35.3–54.5) 50.3 ± 1.92 (48.8–53.1) 52.7 ± 4.84 (44.9–58.5) body length (%svl) 53.7 ± 1.75 (51.5–57.5) 51.3 ± 2.47 (46.1–56.1) 51.4 ± 2.85 (48.4–54.8) 48.2 ± 3.55 (42.3–54.3) 195.3 ± 10.22 216.4 ± 20.28 205.7 ± 23.23 tail length (%svl) 0 (n=0) (188.1–202.5) (n=2) (183.1–251.1) (n=14) (181.1–231.0) (n=4) forelimb length (%svl) 29.7 ± 1.50 (27.0–32.4) 28.1 ± 2.36 (22.9–33.0) 29.0 ± 0.48 (28.3–29.4) 28.8 ± 2.16 (25.5–32.3) hindlimb length (%svl) 51.3 ± 3.49 (47.4–58.0) 43.4 ± 3.77 (34.7–49.8) 46.4 ± 2.41 (43.1–48.5) 46.7 ± 2.54 (42.3–50.0) forebody length (%svl) 38.4 ± 1.32 (36.1–40.5) 39.7 ± 1.93 (36.3–43.7) 39.3 ± 0.84 (38.1–40.1) 40.5 ± 2.28 (37.6–43.8) head length (%svl) 20.1 ± 1.05 (18.5–21.4) 20.2 ± 1.14 (18.1–22.4) 20.3 ± 0.42 (20.0–20.9) 20.8 ± 1.01 (19.3–22.3) head depth (%hl) 53.7 ± 4.65 (47.5–61.1) 47.3 ± 3.82 (39.8–58.9) 50.0 ± 5.77 (41.4–53.7) 50.3 ± 3.50 (45.8–57.0) head width (%hl) 64.6 ± 2.33 (60.7–67.6) 60.2 ± 2.85 (52.2–67.3) 63.9 ± 3.19 (61.3–68.4) 60.2 ± 2.31 (56.3–63.9) snout length (%hl) 42.8 ± 1.61 (41.0–45.9) 43.8 ± 2.24 (40.2–50.4) 44.5 ± 1.76 (42.7–46.6) 44.5 ± 2.74 (40.8–49.7) second 57% second 25% second 40% supraocular (largest) subequal 100% subequal 43% subequal 75% subequal 60% separated 90% contact 25% contact 50% contact 50% prefrontal (contact point) narrow contact 10% separated 75% separated 50% separated 50% narrow separation 80% contact 43% nasal (contact point) separated 100% separated 100% broad contact 20% separated 57% presubocular (presence) present 100% present 100% present 100% present 100% 6th labial 70% 5th labial 36% 5th labial 20% subocular (supralabial) 6th labial 100% 7th labial 30% 6th labial 64% 6th labial 80% upper 10% upper 61% ear lobule (largest) mid 100% mid 100% mid 90% mid 39% subdigital lamellae (condition) callose 100% callose 100% callose 100% callose 100% Three new species of Ctenotus 183 Table 2 Summary of mensural and meristic variables for Ctenotus vagus sp. nov., C. tantillus and C. mesotes sp. nov. Presented are mean (± 1 SD), mode (meristics only) and range in parentheses. C. vagus sp. nov. C. tantillus C. mesotes sp. nov. Character (n=2) (n=38) (n=11) midbody scale rows 26.0 ± 0.00, (26) 27.0 ± 1.33, 28 (24–28) 29.4 ± 1.29, 30 (28–32) paravertebral scales 59.0 ± 2.83, (57–61) 60.8 ± 3.45, 61 (53–68) 63.0 ± 3.32, 63 (57–68) nuchal scales 8.0 ± 0.00, (8) 7.8 ± 1.47, 8 (5–10) 7.2 ± 1.17, 6 (6–9) supralabial scales 8.0 ± 0.00, (8) 7.0 ± 0.16, 7 (7–8) 7.1 ± 0.30, 7 (7–8) infralabial scales 7.0 ± 0.00, (7) 6.6 ± 0.54, 7 (6–8) 6.0 ± 0.00, 6 (6) supraciliary scales 8.0 ± 0.00, (8) 7.9 ± 0.39, 8 (7–9) 8.1 ± 0.54, 8 (7–9) ciliary scales 9.5 ± 0.71, (9–10) 9.3 ± 0.75, 9 (8–11) 10.1 ± 0.54, 10 (9–11) ear lobules 4.0 ± 0.00, (4) 2.9 ± 0.52, 3 (2–4) 2.9 ± 0.30, 3 (2–3) subdigital lamellae (4th finger) 14.0 ± 0.00, (14) 12.7 ± 1.07, 12 (11–15) 13.6 ± 0.82, 14 (12–15) supradigital lamellae (4th finger) 10.0 ± 0.00, (10) 10.1 ± 0.49, 10 (9–11) 10.1 ± 0.70, 10 (9–11) subdigital lamellae (4th toe) 23.0 ± 1.41, (22–24) 22.0 ± 1.32, 22 (19–26) 22.4 ± 1.37, 22 (20–25) supradigital lamellae (4th toe) 15.5 ± 0.71, (15–16) 14.8 ± 1.14, 14 (12–17) 15.4 ± 0.93, 16 (14–17) snout-vent length (mm) 43.8 ± 0.01 (43.8–43.9) 39.2 ± 3.18 (32.5–46.4) 37.7 ± 4.67 (25.7–41.5) body length (%svl) 50.2 ± 2.98 (48.0–52.3) 53.5 ± 3.24 (46.2–60.2) 52.4 ± 2.01 (48.9–54.9) 246.5 ± 0.00 202.6 ± 15.53 211.3 ± 6.30 tail length (%svl) (246.5) (n=1) (167.1–230.8) (n=19) (206.8–218.5) (n=3) forelimb length (%svl) 30.8 ± 0.44 (30.5–31.2) 28.4 ± 1.92 (24.2–32.5) 29.9 ± 2.09 (27.3–34.6) hindlimb length (%svl) 51.1 ± 2.79 (49.2–53.1) 44.8 ± 3.00 (38.1–52.3) 48.1 ± 1.83 (44.7–50.4) forebody length (%svl) 42.6 ± 1.13 (41.8–43.4) 39.3 ± 2.12 (34.8–43.0) 40.0 ± 2.24 (36.7–44.8) head length (%svl) 20.8 ± 0.47 (20.5–21.1) 21.5 ± 1.02 (19.3–23.6) 21.7 ± 1.05 (20.5–23.7) head depth (%hl) 52.8 ± 1.65 (51.7–54.0) 53.1 ± 4.39 (44.7–62.8) 46.8 ± 4.51 (40.2–55.5) head width (%hl) 61.5 ± 1.85 (60.2–62.8) 62.6 ± 3.64 (56.0–70.7) 59.9 ± 3.80 (55.1–67.0) snout length (%hl) 42.6 ± 1.45 (41.5–43.6) 41.6 ± 2.20 (38.4–46.5) 44.1 ± 1.87 (41.1–47.7) second 97% second 91% supraocular (largest) subequal 100% subequal 3% subequal 9% prefrontal (contact point) separated 100% separated 100% separated 100% narrow separation 50% narrow contact 8% narrow contact 73% nasal (contact point) broad contact 50% broad contact 92% broad contact 27% presubocular (presence) present 100% present 100% present 100% 5th labial 97% 5th labial 91% subocular (supralabial) 6th labial 100% 6th labial 3% 6th labial 9% ear lobule (largest) upper 100% upper 100% upper 100% subdigital lamellae (condition) callose 100% keeled 100% keeled 100% 184 P.