Goggia incognita, Bauer, 2017

Bauer, Aaron M., 2017, Molecular phylogeny reveals strong biogeographic signal and two new species in a Cape Biodiversity Hotspot endemic mini-radiation, the pygmy geckos (Gekkonidae: Goggia), Zootaxa 4312 (3), pp. 449-470 : 458-461

Goggia incognita sp. nov.

( Figs. 1 C, 1D, 4, 5A)

Diplodactylus lineatus (part) Gray, 1845

Phyllodactylus lineatus (part) Smith, 1849

Phyllodactylus lineatus lineatus (part) Hewitt, 1937 Goggia lineata (part) Bauer, Good, and Branch, 1997

Holotype. CAS 224024 : adult male. South Africa, Western Cape, Jacobsbaai (32° 59' 19" S, 17° 52' 37" E). Collected by A. M. Bauer, R. A. Sadlier, A. Whiting, 9 September 2001.

Paratypes. CAS 224022 (adult female), CAS 224023 (adult female): same data as holotype. CAS 176047 (adult female): Same locality as holotype. Collected by A. M. Bauer, 23 May 1990. CAS 206692 (adult male), CAS 206697 (adult female): Same locality as holotype. Collected by A. M. Bauer, A. C. Lamb, J. L. Wright, P. Moler, R. D. Babb, 11 July 1998. MCZ R-192442 (adult female): South Africa, Western Cape, Mauritzbaai (32° 58' 39.8" S, 17° 52' 51.9" E). Collected by M. P. Heinicke, A. M. Bauer, T. Gamble, D. Zarkower, J. Marais, A. Kuhn, E. Frietas, R. Skinner, 2 August 2013. MCZ R 192395 (adult females), MCZ R-194417 (adult male): South Africa, Western Cape, 1 km S Jacobsbaai (32° 59´19.1´´ S 17° 52´36´´ E). Collected by M. P. Heinicke, A. M. Bauer, T. Gamble, D. Zarkower, J. Marais, A. Kuhn, E. Frietas, R. Skinner, 24 July 2013. MCZ R-192446 (subadult male), MCZ R-194450 (adult male): South Africa, Western Cape, 4.3 km S Jacobsbaai (33° 0´20.9´´ S, 17° 52´46.5´´ E). Collected by M. P. Heinicke, A. M. Bauer, T. Gamble, D. Zarkower, J. Marais, A. Kuhn, E. Frietas, R. Skinner, 2 August 2013.

Referred Specimens. See Branch et al. (1995): all specimens listed as Goggia lineata from south of 31° S.

Etymology. The specific epithet is from the Latin word incognitus, meaning “not known”. The English phrase “going incognito” refers to remaining hidden or disguised. The name is chosen to reflect the 150+ year time period in which this species has remained hidden within what were considered nominotypical populations of Goggia lineata . It additionally reflects the natural history of the species, as members of the species are typically inconspicuous and hidden under cover objects by day. The name is used as an adjective.

Diagnosis. A small-bodied Goggia , snout-vent length to 28.58 mm. Body form is cylindrical, with a deep head and short, rounded snout. The rostral scale bears a median cleft, and snout scales are relatively large and domed, with 8–10 rows of scales between the rostral and the anterior margin of the orbits. Dorsal scalation is homogenous, consisting of uniform flattened subimbricate scales, grading to clearly imbricate on the venter. Midbody scale rows number 73–81. Digits bear a single pair of subdigital scansors (“leaf toes”) enclosing a small claw. Males typically have five precloacal pores. Typical color pattern consists of a gray background overlain with a series of small, often unnoticeable pale spots with dark anterior margins that typically fuse to form a series of scallops or chevrons. Some individuals additionally bear four dark longitudinal stripes, which in this species are always connected by the aforementioned scallops.

The combination of leaf toes, atuberculate dorsal scalation, and cleft rostral distinguishes this species from all non- Goggia geckos in southern Africa. Goggia incognita sp. nov. can be distinguished from G. microlepidota based on its much smaller body size (maximum SVL 29 mm in G. incognita sp. nov. vs. 67 mm in G. microlepidota ). All small-bodied Goggia except for G. lineata can be easily distinguished from G. incognita sp.

nov. based on color pattern: in G. braacki , G. essexi , G. hewitti , and G. hexapora , the pale spots and dark pattern elements form a clear reticulated pattern. In G. gemmula and G. rupicola (including “ rupicola ” from Kliprand described as another new species below), the pale spots are large and are yellow or orange rather than white or cream. In addition to color pattern, G. braacki and G. hewitti differ from G. incognita sp. nov. in being largerbodied (SVL to 35 mm in G. braacki , 37 mm in G. hewitti ), having only four precloacal pores in males, and in having more midbody scale rows (usually more than 80). Goggia essexi , G. gemmula , G. rupicola , and G. “ rupicola ” also have only four precloacal pores in males; G. essexi , G. rupicola , and G. “ rupicola ” also have flattened bodies and typically more than 80 midbody scale rows, whereas G. gemmula has a more elongate body than G. incognita sp. nov. Goggia hexapora usually has six precloacal pores in males and more than 80 midbody scale rows. Goggia lineata is the species most similar to G. incognita sp. nov., but can be distinguished as having a color pattern typically dominated by bold longitudinal stripes ( Fig. 1 ), and having smaller, flatter scales on the head, with 11 or more rows between the rostral and the anterior margin of the orbits, vs. 8–10 in G. incognita sp. nov. ( Fig. 5 ).

Description of the holotype. Adult male. SVL 26.62 mm. Body cylindrical, trunk not elongate (AGL/SVL ratio = 0.45). Head deep, not dorsoventrally flattened (HW/HD ratio = 1.75); snout rounded, about twice the diameter of the orbit. Lores inflated, interorbital region slightly concave. Ear opening is small, obliquely rounded, and without a tympanic shield. The rostral is subpentagonal with a median cleft, and the rostral along with the first supralabial and three nasals enter the nostril. The largest nasal borders the rostral. The nasorostrals are separated by a single granule. Supralabials number 7/6 (R/L), infralabials 6/6 (R/L); the mental is subpentagular with a shallow apex and is bordered by two enlarged chin shields, which are in turn bordered by six smaller granules. The snout is short, and snout granules are noticeably enlarged, rounded, and more domed than scales elsewhere on the head; there are eight rows of scales from the rostral to the level of the anterior edge of the orbit, and eight granules from the nostril to the anterior edge of the orbit. Scales on the crown are smaller and flatter, with 15 granules separating the anterior margins of the orbits.

Dorsum covered by uniform, smooth, flat subimbricate scales, with subimbrication resulting in rhomboid appearance to the scalation; the grade to larger, smooth, imbricate scales on the belly which are hexagonal in shape and may have denticulate edges. At midbody are 78 scale rows. Five precloacal pores are present anterior to the cloaca, and three enlarged tuberculate scales (cloacal spurs) are present on either side at the tail base along the hemipenial bulges. The limbs are relatively short (FL/SVL ratio = 0.15), covered in uniform, subimbricate or imbricate granules, with the median series slightly broader than lateral scale series. The toe tips are rounded with small expansions bearing a pair of large, rectangular scansors (toe pads) between which is a small claw. The tail is cylindrical, tapering, regenerated. Original portion of the tail measures 3.88 mm; the regenerated portion is an additional 14.99 mm. The unregenerated portion of the tail is covered above with regular rows of uniform, smooth granules, whereas the ventral surface has larger, flatter imbricate scales. The regenerated portion of the tail is entirely covered in large imbricate scales.

Coloration. In preservative, the dorsum is gray-brown in color. Barely perceptible dark temporal lines extend from the eyes above the ears to the nape. On the dorsum, a series of faded dark scallops extend transversely across the dorsum, the dark scallop on the unbroken portion of the tail being least faded. Neither pale spots nor longitudinal stripes are visible. The regenerated tail is more brown and less gray than the remainder of the body. Ventrally, the body is immaculate and cream-colored.

In life, the ground color is gray without brown infusion. The pattern is as in preservative, with dark temporal lines above the ears and a series of transverse scallops of the dorsum, but is much more obvious and not faded. The venter remains cream-colored, and the regenerated tail is more brownish than the remainder of the body.

Variation. Scale counts in the paratype series show minor variation compared to the holotype ( Table 4). Chin shields sometimes three instead of two in MCZ R-192442 and CAS 224023. The number of granules bordering the chin shields varies from 5–7 (mean = 6.27). In specimens MCZ R-192395, MCZ-R192442, and MCZ R-194450, two granules separate the nasorostrals instead of one. The size of the granules on the head varies slightly, with 7–9 granules between the nostrils and the anterior orbit margin (mean = 8.27), 12–16 granules across the crown at the anterior margin of the orbit (mean = 14.6), and 8–10 granules from the rostral to the anterior margin of the orbit (mean = 9). Midbody scale rows vary from 73–81 (mean = 76.5). Coloration in the paratypes is similar to the holotype, but in some individuals more noticeable longitudinal stripes are present, or the dark scallops are arranged such that both transverse and longitudinal patterns are formed.

Distribution and Natural History. Goggia incognita sp. nov. is endemic to South Africa, being known from much of the western part of Western Cape Province, with additional records from further east in the Little Karoo and Karoo, also in Western Cape Province. The distribution of this species comprises what was formerly considered the southern half of the distribution of G. lineata . The boundary between the two species appears to be at the Knersvlakte, a quartz plain lying between the Cape Fynbos and Little Namaqualand ecoregions, near the border between the Western Cape and Northern Cape provinces, with G. incognita sp. nov. occurring only to the south in the Cape ( Fig. 2 ).

Many references to the ecology and natural history of Goggia lineata in both the technical and popular literature actually refer to G. incognita sp. nov., and the two species are ecologically similar. Goggia incognita sp. nov. is a terrestrial, nocturnal species that shelters by day under a wide range of available debris, including under stones, in plant litter, and under or within dead Aloe stems (Branch & Bauer 1995, Branch & Braack 1989, Branch 1998). At the type locality, along the coast, individuals may be encountered both under boulders and under strand debris. At Farm Buffelskloof, in the Little Karoo, no individuals were found sheltering under the local conglomerate rock, but one individual was found inside a dead Aloe . Regenerated tails are very common in this species, and individuals also often autotomize their tails when handled even if the tail is not grasped, suggesting that tail autotomy is a frequently employed defense mechanism. Gecko species found syntopically with G. incognita sp. nov. (and potentially under identical cover objects) include Afrogecko porphyreus and Pachydactylus geitje near Jacobsbaai and Goggia hewitti and Pachydactylus geitje at Farm Buffleskloof.

Figures

FIGURE 1. Goggia species in life, depicting pattern variation in small-bodied species. (A) Goggia lineata from Garies, Northern Cape, striped form. (B) Goggia lineata from Port Nolloth, Northern Cape, chevron form. (C) Goggia incognita sp. nov. from Jacobsbaai, Western Cape, striped form. (D) Goggia incognita sp. nov. from Doringbaai, Western Cape, chevron form. (E) Goggia hexapora from Farm Waterval, Western Cape. (F) Goggia matzikamaensis sp. nov. MCZ R- 192186. Photo credits: (A) André Coetzer. (B) Luke Kemp. (C, D) Tony Gamble. (E, F) Matthew Heinicke.

FIGURE 2. Geographic ranges of Goggia species and sampling localities of specimens included in the study. Countries are labeled in large white text, provinces of South Africa in small white text, and key geographic regions in small black italic text. Colored shaded regions depict overall ranges of species with localities inside these regions; note that shade colors are used twice as follows: red— braacki (east), gemmula (west); yellow— essexi (east), lineata (west); green— hewitti (east), matzikamaensis sp. nov. (west); blue— hexapora, microlepidota (fully overlapping); violet— incognita (south), rupicola (north).

FIGURE 5. Head scalation in Goggia incognita sp. nov., CAS 224022 (A) vs. Goggia lineata, CAS 85927 (B) and MCZ R- 45427 (C). Note smaller snout and crown scales in G. lineata.