Pedioplanis mayeri, Childers & Kirchhof & Bauer, 2021

Childers, Jackie L., Kirchhof, Sebastian & Bauer, Aaron M., 2021, Lizards of a different stripe: phylogenetics of the Pedioplanis undata species complex (Squamata, Lacertidae), with the description of two new species, Zoosystematics and Evolution 97 (1), pp. 249-272 : 249

Pedioplanis mayeri sp. nov. Figs 3 , 4 , 5

Holotype

(Fig. 3 ). • Adult ♀; MCZ-R193179 (field number MCZ-A28704); Namibia, Erongo Region, Omaruru District, at Farm Omandumba, ca. 1 km W of house (-21.49786, 15.62630, 1238 m above sea level (a.s.l.)); collected 15 June 2014 by Jackie L. Childers, Aaron M. Bauer, William R. Branch, Matthew Heinicke and Johan Marais. Holotype and part of type series to be transferred to the National Museum of Namibia.

Paratypes.

n = 8 (all specimens are adults unless otherwise noted); three ♀: CAS 214643, MCZ-R185872, ZMB 89349; five ♂: CAS 214645, MCZ-R185870, MCZ-R190213, MCZ-R193125, ZMB 89350 collected from various localities in the Kunene Region of northern Namibia • CAS 214643; 59 km W of Kamanjab (-19.64871, 14.33984, 1163 m a.s.l.); collected 1 June 2000 by Aaron M. Bauer • CAS 214645; same collection data as for proceeding • MCZ-R185870; 35 km S of Epupa Falls on Okangwati Rd. (-17.26083, 13.21194, 1035 m a.s.l.); collected 14 August 2007 by Aaron M. Bauer, Johan Marais, Ross A. Sadlier, and Stuart V. Nielsen • MCZ-R185872; N Okangwati on Epupa Falls Rd. (-17.40361, 13.15861, 1140 m a.s.l.); collected 14 August 2007 by Aaron M. Bauer, Johan Marais, Ross A. Sadlier, and Stuart V. Nielsen • MCZ-R190213; ca. 4 km from Swartbooisdrif towards Epembe (-17.38136, 13.82955, 836 m a.s.l.); collected 27 November 2011 by Aaron M. Bauer • MCZ-R193125; collected at the type locality on 13 June 2014 • ZMB 89349; subadult ♀; along the C35 road, ca. 2 km N of Fransfontein (-20.19976, 15.01453, 1097 m a.s.l.); collected 15 August 2014 by Sebastian Kirchhof • ZMB 89350; along the C43 road, 29 km N of Palmwag (-19.62736, 13.87391, 1124 m a.s.l.); collected 15 August 2014 by Sebastian Kirchhof. Elevation data for the holotype and paratypes was obtained using the GPS or, if not available, from Google Earth (earth.google.com) using georeferenced GPS coordinates from the collecting localities.

Diagnosis.

Distinguished from P. lineoocellata , P. laticeps and P. burchelli by having 10 longitudinal ventral scale rows (vs. 12 or more). It is distinct from P. gaerdesi , P. benguelensis , P. husabensis , P. namaquensis and P. breviceps in possessing a semi-transparent lower eyelid with a brille formed by 2-4 enlarged scales (brille formed by a single scale in P. benguelensis and P. gaerdesi , lower eyelid with eight opaque scales in P. husabensis and opaque and scaly in P. breviceps and P. namaquensis ). Dorsal patterning is characterized by the presence of five, usually bold dark brown to black, straight-edged dorsal stripes, distinguishing it from P. rubens (dorsum and tail uniform red-brown to brick red, lacking conspicuous markings with only a hint of a slightly brighter dorso-lateral line on each side), P. inornata , P. gaerdesi and P. branchi sp. nov. (dorsum may be light to dark gray becoming gradually more reddish towards the tail, possessing dark and/or light beige-yellowish speckling but lacking distinct longitudinal elements), P. haackei (only three dark dorsal stripes), and P. undata (dorsal striping bold or not, may be reduced with pale longitudinal elements or even a single middorsal stripe restricted to the nape). It is further distinguished from P. haackei by typically having a smaller number of granules anterior to the first supraocular (9-16 vs. 12-32), from P. huntleyi in having a larger number of granules anterior to the first supraocular (9-16 vs. 7-13), and from P. undata in possessing a greater maximum number of granular scales anterior to the supraoculars (9-16 in P. mayeri sp. nov. versus 8-13 in P. undata ), and a greater maximum number of femoral pores on a single leg (12-16 in P. mayeri sp. nov. versus 11-14 in P. undata ) (see Suppl. material 7: Table S4 and Suppl. material 3). Pedioplanis mayeri is similar in most characteristics to P. huntleyi , which is restricted to Angola, but the latter species is typified by the restriction of the five dark dorsal stripes to the anterior half of the trunk, a condition found in only some P. mayeri . No single morphological character unambiguously distinguishes the allopatric species P. mayeri , P. undata and P. huntleyi . We therefore provide several diagnostic characters based on the mitochondrial gene ND2 in order to supplement the morphological data. Pedioplanis mayeri may be distinguished from all other Pedioplanis species in being characterized by having the amino acid histidine instead of a tyrosine at base pair 61 due to a codon change at that position. It also has the amino acid phenylalanine at base pair 223, instead of a threonine ( P. benguelensis , P. breviceps , P. haackei , P. huntleyi , P. husabensis , P. laticeps , P. lineoocellata , P. namaquensis ), an alanine ( P. burchelli ), or a serine ( P. branchi sp. nov., P. gaerdesi , P. inornata , P. rubens , P. undata ) due to a codon change at that position. Finally, it has the amino acid threonine due to a codon change at base pair 568, instead of a leucine ( P. rubens ), a valine ( P. haackei , P. laticeps , P. undata ), or an isoleucine ( P. benguelensis , P. branchi sp. nov., P. breviceps , P. burchelli , P. gaerdesi , P. husabensis , P. namaquensis ); P. inornata and P. lineoocellata are polymorphic with individuals possessing either valine or isoleucine, and it is unknown what the molecular character state is for P. huntleyi at this position.

Description of holotype.

Body relatively slender; SVL 45.5 mm; interlimb distance 20.4 mm; femur 10.0 mm; tibia 9.8 mm; humerus 5.5 mm; forearm 5.8 mm; body length 28.9 mm from groin to collar; collar-snout length 16.1 mm; fourth finger length 5.7 mm; fourth toe length 11.1 mm; head narrow and elongated (head width 52% of head length) with narrow pointed snout (width at rear of frontonasal 2.2 mm, width at front of eye 3.8 mm); head length 11.0 mm; head width 5.7 mm; lower jaw length 8.5 mm; eye-ear distance 4.1 mm; eye-nostril distance 3.8 mm; 1.6 mm between the nostrils; original unregenerated tail 116.7 mm. Rostral semicircular, contacting nasals and supranasals; nostril surrounded by nasal, supranasal, and postnasal; nasals unraised relative to rostral and frontonasal; postnasal contacts nasal, supranasal, frontonasal, anterior loreal, and enters the nostril; nostrils circular; two loreals, anterior half the length of the posterior; two preoculars; prefrontals in median contact; frontal large, with a narrow posterior projection that contacts the frontoparietals; frontoparietals in medial contact; interparietal in contact anteriorly with both frontoparietals, laterally with the parietals, and posteriorly with the occipital; occipital partially fused with parietals at posterior margin; two supraoculars, both in contact with the frontal, preceded anteriorly by a group of 15R/16L granules, two granules in contact with prefrontal and two in contact with frontal (L); one granule in contact with prefrontal and two in contact with frontal (R); two rows of granules dividing anterior supraocular from supraciliaries; three small scales between last supraciliary and parietal; six supraciliaries on each side, anterior-most longest; lower eyelid with transparent brille formed of two larger, black-edged scales, with a row of five smaller scales below; five supralabials anterior to subocular and three supralabials posterior to subocular, on both sides; subocular bordering lip, its lower edge narrower than its upper; 6R/6L infralabials; first infralabial in contact with the second infralabial, the first chin shield, and the mental; four enlarged pairs of chin shields, the first three in median contact and enlarging progressively to the posterior; two enlarged temporals; tympanum sunken; no scales projecting significantly past margin of ear opening; enlarged narrow scale at anterodorsal margin of tympanum. 28 gular scales in a straight line between symphysis of chin shields and median collar plate; collar free, comprising 11 enlarged plates (median trapezoidal) and extending onto side of neck as a crease that terminates midway up the lateral surface; dorsal scales small, juxtaposed, granular, without keels, lateral scales becoming increasingly larger ventrally; 53 rows of granular scales around the midbody; ventral plates in 10 longitudinal and 30 transverse rows (from collar to groin); ventral scales squarish, subimbricate; single transverse row of ventrals across chest just posterior to collar longer than broad; 11 enlarged precloacal scales, irregularly sized; scales on upper surface of forearm large, smooth, and overlapping, without keels; scales on lower surface of forearm with a series of enlarged plates, at least twice width of scales on upper forearm; scales on upper surface of tibia rhombic, subimbricate and distinctly keeled, below with a series of enlarged plates; scales on upper surface of femur keeled with enlarged scales along the anterior margin; 15 femoral pores on each side; 27 subdigital lamellae under fourth toe; scales on tail uniform, obliquely rectangular in shape, and strongly keeled; 24 presacral vertebrae.

Color in alcohol.

Dorsum of crown gray-tan with small speckles of varying size on head shields; dorsum of snout tinged with reddish-brown. Lateral surface of head cream-colored with minute gray speckles on loreal scales, supralabials and infralabials. Granules bordering lower eyelid window white. Color and pattern of temporal region confluent and consistent with those on trunk. Trunk dorsum with three bold black stripes each bordered on either side by whitish-cream stripes that extend to the sacrum, becoming indistinct on the tail; middorsal black stripe divided anteriorly by a whitish-cream stripe that extends from the occiput to the level of the forelimb insertion, narrowing from a width of five granular dorsal scales to two from anterior to posterior. Below the lateralmost of these pale stripes, which originates on the temporal, lies a thick darkly pigmented line to which is fused the coalescence of a series of 9R/8L irregularly sized ocelli with pale gray-blue centers comprising 6-14 granules, each surrounded by a brown to black ring. This in turn is bordered ventrally by a diffuse white line which begins at the corner of the mouth, passes through the ear and continues to the groin. Below this line the flanks transition to the immaculate pearly white of the venter. Dorsal surfaces of forelimbs mottled brown with margins of enlarged scales pale; dorsal surfaces of hind limbs medium brown, enlarged scales on preaxial surface similar to those of forelimb, postaxial surfaces bearing scattered cream-colored spots, each 1-3 granular scales in extent; palms and soles gray with scattered diffuse pinkish to orange markings. Tail light brown, densely speckled with darker markings which continue the bold lateral black stripes of the body dorsum as a pair of narrow dark brown stripes running along the medial-most keels of the tail for at least three quarters of its length.

Variation within the type series.

Measurements for the type series are summarized in Table 1 and mensural (n = 13) and meristic (n = 17) character data based on measurements of additional museum vouchers can be found in Suppl. material 2, 3, respectively. Paratypes have similar scalation to the holotype except as follows: in MCZ-R185872 the prefrontals do not contact and are instead divided by a granule; in MCZ-R193125 the interparietal and occipital are separated by a granule; in all paratype specimens the occipital is not fused with the parietals; the number of granules in the group preceding the anterior supraocular varies from nine to 15; in CAS 214645 and ZMB 89349 there is one row of granules dividing the anterior supraocular from the supraciliaries (usually two); in CAS 214645 and MCZ-R185870 there are 7R and 7L infralabials, respectively (usually six); gular scales in a straight line between the symphysis of chin shields and the median collar plate varies from 27 to 32; midbody scale rows vary from 57 to 64; subdigital lamellae under the fourth toe range from 25 to 28; unilateral femoral pores number 13 to 14 (right side only); and presacral vertebrae number either 24 or 25.

Coloration in life

(Fig. 4 ). Dorsal coloration and pattern varied considerably across examined specimens. Dorsum of head gray-tan, sometimes possessing dark speckles of varying size; dorsum usually bearing three bold black, medium-brown or gray stripes bordered on each side by white stripes; dorsal stripes often terminate at the tail base or begin to fade into a gray and reddish hue midway towards the tail base; dorsal stripes may be absent entirely, with individuals possessing a uniformly gray dorsum, sometimes with dark speckling. All individuals examined possess yellow-centered ocelli or yellow spots along the flanks, usually bordered ventrally by a white stripe and dorsally by a black stripe (or with the dark rims of the ocelli confluent with such a stripe); lateral spots or ocelli vary in size from ca. 0.5 to 1.0 mm in diameter, in some cases smaller spots may merge with the white ventral stripe; anterior surface of the thighs and outermost ventral plates sometimes tinged or speckled with orange; limbs and feet more or less uniformly grayish (front), reddish-brown to brown, or speckled with light or black dots or blotches that may form bars; tail usually bright brick or orange-red, in some cases dark speckling may be present on the dorsal surface of the tail.

Coloration in alcohol.

Pattern as described above though dark stripes may fade to dark gray, yellow lateral spots may appear cream white or gray-blue, and red coloration usually present on the dorsum of the midbody and tail may become a faded orange-pink or may fade to a faint, golden-brown hue.

Distribution.

Pedioplanis mayeri sp. nov. is endemic to northern Namibia and occurs from south of the Kunene River and east of the Namib Desert along the eastern side of the escarpment, thence throughout the eastern Kunene Region, entering the northeastern parts of the Erongo Region and east through the Otjozondjupa Region, reaching at least as far east as Oshikango (TM17028) in the north, Gobabis (Omaheke Region) in the south-east, and Nauchas in the south. It does not enter the Kalahari dune fields, and is possibly absent from the Khomas Hochland, where it is replaced by P. undata (see Fig. 6 for map of locality records).

Etymology.

The specific epithet is a patronym formed in the genitive singular honoring our friend and colleague, the Austrian lacertid specialist Werner Mayer (1943-2015), who first recognized the distinctiveness of his namesake species and whose contributions to the study of Pedioplanis have been seminal.

Natural history.

Pedioplanis mayeri is widespread in northern Namibia and inhabits Tropical & Subtropical Grasslands, Savannas & Shrublands and Deserts & Xeric Shrublands biomes (following the classification of the WWF; Olson et al. 2001), but it is absent from true desert. Within the occupied biomes, P. mayeri inhabits Namibian savanna woodlands, Kalahari xeric savanna, Kalahari Acacia-Baikiaea woodlands and Angolan Mopane woodlands (terminology follows Olson et al. 2001). Here, the species is active on sandy clay soils and more compact, hard soils, rocky flats and slopes, in dense grassy patches as well as in more open areas interspersed with shrubs (see Fig. 5 for images of characteristic habitats). In rocky areas and stony slopes individuals were found sleeping under stones. The majority of the species’ range comprises Namibia’s arid regions with a median annual precipitation of 279 mm (61-559 mm) and a median annual temperature average of 21.1 °C (18-23.5 °C) (all climate data taken from Fick and Hijmans 2017). Pedioplanis mayeri mainly occurs along the northern parts of the Great Escarpment at a median elevation of 1160 m a.s.l., but reaches altitudes as high as ca. 1600 m a.s.l. in Otjozondjupa, and probably as low as ca. 200 m a.s.l. in the north along the Kunene River. The largest recorded individual was a female with SVL = 57 mm (see also Kirchhof et al. 2014; the individuals referred to therein as P. undata are now P. mayeri ). Breeding season appears to be in spring, similar to other southern African Pedioplanis spp. Gravid females with up to four eggs were found in December and February, and small juveniles (SVL = 27 mm) appeared in mid-February ( Kirchhof et al. 2014). Sympatric ground-living diurnal lizards include Trachylepis damarana , Meroles squamulosus , Heliobolus lugubris , Gerrhosaurus flavigularis , and Agama anchietae , among others.

Conservation.

The species occurs across a wide area of Namibia in which potential threats from agriculture and mining are scattered and localized. Local populations occur in protected areas within Etosha National Park and Waterberg Plateau Park as well as in many local conservancies. Applying IUCN criteria, we consider P. mayeri to be Least Concern.

Figures

Figure 3. Pedioplanis mayeri sp. nov. adult female holotype (MCZ-R 193179) from Farm Omandumba in the Erongo Region of Namibia. (a.) Dorsal and (b.) ventral views of the whole body; scale bars indicate 10 mm; (c.) dorsal, (d.) ventral) and (e.) lateral views of the head; scale bar indicates 2.0 mm.

Figure 4. Life photographs of representative individuals of Pedioplanis mayeri sp. nov. highlighting color pattern variation within the species. (a.) Dorsal and (b.) lateral whole body images of an adult possessing bold dorsal stripes collected at the type locality (Farm Omandumba, Erongo Region, Namibia), note the row of yellow spots along the flanks; (c.) Dorsal image of an adult from the Kamanjab area depicting fainter, medium-brown dorsal stripes; (d.) An adult female collected from Gobabis (ZMB 80391; see also Fig. 5 a) with dorsal striping of varying boldness and a more grayish-brown hindbody compared to the more reddish hindbody observed in other individuals.

Figure 5. Habitat of Pedioplanis mayeri sp. nov. (a.) Collection site near Gobabis for ZMB 80389 - 80392 in open savannah woodland, with tall, dense grasses and introduced Opuntia. (b.) Collection site for ZMB 89350 (29 km N of Palmwag, Kunene Region, Namibia) in stony Pro-Namib habitat with sparse vegetation dominated by Euphorbia damarana (center).

Figure 6. Topographic maps showing locality records for all the species of the Pedioplanis undata species complex and P. husabensis: (a.) P. husabensis (b.) P. mayeri sp. nov. (c.) P. rubens (d.) P. branchi sp. nov. (e.) P. gaerdesi (f.) P. undata (g.) P. inornata. Black dots represent museum vouchers from various museum collections, those with a white center were sequenced and included in the phylogenetic analyses. Museum voucher information was collected from the California Academy of Sciences San Francisco / USA, Carnegie Museum of Natural History Pittsburgh / USA, Ditsong National Museum Pretoria / South Africa, Iziko South African Museum Cape Town / South Africa, Museum fuer Naturkunde Berlin / Germany, Museum of Comparative Zoology Harvard University / USA, Museum of Vertebrate Zoology Berkeley / USA, Natural History Museum of Los Angeles County / USA, Bayworld Museum Port Elizabeth / South Africa, National Museum of Namibia Windhoek / Namibia, Zoological Research Museum Alexander Koenig Bonn / Germany, in parts via the Global Biodiversity Information Facility (GBIF; https: // www. gbif. org /).