PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, NY 10024 Number 3524, 13 pp., 4 figures July 31, 2006 A New Species of Gekkonid Lizard (Sphaerodactylinae: Gonatodes) from Guyana, South America CHARLES J. COLE1 AND PHILIPPE J. R. KOK2 ABSTRACT AnewspeciesofGonatodesfromcentralGuyanaisdescribed,illustrated,andnamedinhonorof oneofGuyana’soutstandingcitizens,Mr.AlexanderMendes.Todate,thespeciesisknownonly from rain forest habitat at two localities. One (the type locality) is in the drainage system of the KonawarukRiver,awesterntributaryoftheEssequiboRiver,withitsconfluencetothesouthof the PotaroRiver confluence. Theotherlocality isKaieteur National Park, onthe Potaro River. DEDICATION This report is dedicated to Mr. Gerald King (deceased), an American Indian from Wiruni, on thelowerBerbiceRiver,Guyana.LikeothernativeAmericansandGuyaneseofhistime,Mr.King livedincloseassociationwiththerainforest,andheknewitsplantsandanimalswell,particularly thelargerspeciesthatwereusefulforvariouspurposes.CarolR.TownsendandC.J.C.hadgreat pleasure working with Mr. King and his teenage son, Wesley, for two years, during which they builtourcomfortableremotecampsoutoflocalforestresources.TheKingseagerlyassistedwith ourfieldwork,anxioustolearnmoreabouttheirnativeamphibiansandreptilesandtotraveland explorein parts oftheir country theyhad neverseen. 1DivisionofVertebrateZoology(Herpetology),AmericanMuseumofNaturalHistory ([email protected]). 2Department of Vertebrates, Royal Belgian Institute of Natural Sciences, 29 rue Vautier, B-1000 Brussels, Belgium ([email protected]). CopyrightEAmericanMuseumofNaturalHistory2006 ISSN0003-0082 2 AMERICAN MUSEUMNOVITATES NO. 3524 INTRODUCTION South America: limbs four; ventral surface covered with small, flat, smooth, rounded, During the 1990s Carol R. Townsend and imbricate scales; top of head covered with C.J.C. participated in the herpetological re- minute granular scales; eyelids absent or search of the Biological Diversity of the rudimentary; pupil round (except elliptical in Guiana Shield Program (BDG), a collabora- Gonatodes antillensis); digits not dilated, or tion between the University of Guyana and only slightly so proximally, slender through- the U.S. National Museum of Natural out their length, with single row of subdigital History, Smithsonian Institution. Our goals lamellae; digits not straight, distal phalanges were to conduct research on the unisexual at angle between second and third phalanges; speciesoflizards,todevelop achecklistofthe claws not retractile, usually with two scales at herpetofauna of Guyana as part of the larger base (one dorsal, one ventral); adult males program of the BDG to improve knowledge with escutcheon scales on belly and ventral of the biological resources, and to contribute surfaces of thighs; femoral pores absent; to the education of Guyanese students with dorsal scales basically homogeneous, granu- relevant interests. Our approach was to lar, juxtaposed; tongue fleshy (Peters and conduct annual field trips to localities within Donoso-Barros, 1970; Hoogmoed, 1973; Guyana that had not previously been studied Rivero-Blanco, 1979; Avila-Pires, 1995). herpetologically, and to assemble a collection Furtherinvestigationofthe16specimensin of scientific specimens that represent the local the C.J.C. and P.J.R.K. collections and de- species, focusing primarily on one locality tailed comparisons with other specimens of each year. Meanwhile, in 2004–2005, the genus Gonatodes (see appendix) and P.J.R.K., in collaboration with Georges relevantliteratureindicatedthatwehadfound Lenglet (Royal Belgian Institute of Natural an undescribed species, which both authors Sciences [IRSNB]), Godfrey Bourne realized independently. Consequently, we (University of Missouri, Saint Louis brought our data together, and here we [UMSL]), and a team of local counterparts describe, illustrate, and name the species. andtrainees,madethreefieldtripstoKaieteur National Park, central western Guyana, with the aim of contributing to conservation METHODS planning and management while studying amphibians and reptiles (e.g., Kok, 2005). We followed the methods and illustrations In 1998, C.J.C. and Townsend obtained of Rivero-Blanco (1979) and Avila-Pires a series of six geckos of a species they had (1995). Most of the characters are standard, never seen on previous trips to Guyana or but a few require comment here. In counting to neighboring countries. Furthermore, this subdigital lamellae, only those that were seen species was not represented in any of the to be literally on the ventral surface of the literature relevant to Guyana or the broader finger or toe were counted, not including the Guianan Region (Peters and Donoso-Barros, claw. The number of scales around midbody 1970; Hoogmoed, 1973; Avila-Pires, 1995, wascountedonalineatthemidpointbetween 2005; Gorzula and Senaris, ‘‘1998’’ [1999]; the axilla and groin. The number of ventrals Reynoldsetal.,2001–present;Donnellyetal., along the midventral line of the body was 2005, and personal commun.). The team with determined by starting at an imaginary line P.J.R.K. collected 10 specimens of the same betweentheanteriorpartofthearminsertions taxon in Kaieteur National Park in 2004– with the body and counting posteriorly to the 2005. vent, not including minute granules lining the Thefollowinglistofcharacterspossessedby edgeofthecloaca.Thenumberoflateralrows our combined collections of 16 specimens of of scales distally on fingers and toes was these lizards identify them as representatives counted on the fourth digit. The number of of the gekkonid genus Gonatodes ventrals across the abdomen at midbody and (Sphaerodactylinae), which currently has 18 the numbers of enlarged supralabials and recognized species (Kluge, 1993; Esqueda, infralabials, although used by specialists, are 2004), most of which occur in northern not really discrete characters, because the 2006 COLE AND KOK: GEKKONID LIZARD FROMGUYANA 3 scales change in size in graded series, so the Trail (ca. 1.2 km from the Kaieteur airstrip), cutoff points for the counts are somewhat ca.400 melevation,at5u119130N,59u289540W, subjective. inWGS84(IRSNB2637–2639). Specimenswereinitiallyfixedin10%forma- ETYMOLOGY: Thespecificepithet,anounin lin and later transferred to 70% ethanol. For thegenitivesingularcase,honorsMr.Alexander specimen catalog numbers, AMNH refers to Mendes, a third-generation Guyanese from the American Museum of Natural History, the capital city, Georgetown, who also New York, New York; IRSNB refers to the manages Dubulay Ranch on the Berbice Royal Belgian Institute of Natural Sciences, River. Mr. Mendes is an important member Brussels; and RMNH refers to the Nationaal of the business community of Guyana and, NatuurhistorischMuseum,Leiden,theNether- among other things, an active conservation- lands. ist, explorer, and adventurer, who is keenly interested in ethical and responsible nation- THE NEW TAXON building. For the last five field trips of C.J.C. and Carol R. Townsend to Guyana, Mr. Gonatodes alexandermendesi, new species Mendes provided invaluable advice, logistical Figures 1, 2, 3 support, and security, with consistent re- liability, while being ever anxious himself to HOLOTYPE: AMNH R-151805 (field num- learn about new discoveries. ber JC 7802), an adult male collected on 8–9 DIAGNOSIS: This species differs from all March 1998 by C.J.C., Carol R. Townsend, known species of Gonatodes by the following Deokie (Jackie) Arjoon, Gerald King, and combination of characters: very elongate Wesley King at the following site in spine on supraciliary flap over eye; 4 lateral GUYANA: Magdalen’s Creek Camp, near rows of scales distally on fingers and toes; (ca. 275 m north) the northwest bank of the beneath tail a row of enlarged hexagonal Konawaruk River (ca. 40 km [linear] WSW midventral subcaudal scales distinctly wider Mabura Hill), 120 m elevation, 5u139070N, than adjacent scales; with or without a few 59u029430W, in WGS 84. The Konawaruk tiny,inconspicuousclusters(about4granules) River flows into the western side of the ofpalescalesonneckand/orbody,sometimes Essequibo River to the south of the Potaro containingsomewhatenlargedgranules;scales River confluence. Alexander Mendes trucked on dorsal base of tail suddenly becoming flat, us to the site, reached by crossing the smooth, rounded, imbricate (rather than Essequibo River on a pontoon boat about conical). 0.8 km downriver (N) of the mouth of the According to Rivero-Blanco (1979), only Konawaruk River, then continuing WSW one species, Gonatodes hasemani, among the from gravel road mileage marker number 19 (just west of the Essequibo River) to about 18 currently recognized species of Gonatodes midway between mileage markers 37 and 38 (Kluge, 1993; Esqueda, 2004), has a very ontheMazdaMineconcession(nowMekdeci elongate spine on the supraciliary flap over Mining Company), where the road crossed theeye,whichisalsofoundinallspecimensof Magdalen’s Creek. G.alexandermendesi(fig. 2).Inaddition,until PARATYPES: Specimens from the type lo- now, only G. hasemani was known to have calityareAMNHR-151804andR-151806–R- elongate granules in small white patches on 151809(JC7749,7885,7897,7936,and7992), the body and base of the tail, as seen, but threemalesandtwofemalesthatwerecollected much less extensively developed, in some 3–19 March 1998.Thefollowing 10specimens specimens (not all) of G. alexandermendesi. arefromanotherlocality:GUYANA:Potaro- In some G. alexandermendesi there are in- Siparuni District; Kaieteur National Park, conspicuous spots with somewhat enlarged along Tukeit Trail (ca. 3 km from the granules; other specimens have inconspicuous Kaieteur airstrip), ca. 420 m elevation tinypalespotswithoutenlargedgranules;and (IRSNB 2630, 2631); along Tukeit Trail (ca. others have neither pale spots nor enlarged 2.3 km from the Kaieteur airstrip), ca. 410 m granules. However, G. hasemani also has the elevation (IRSNB 2632–2636); along Tukeit following characters that distinguish it from 4 AMERICAN MUSEUMNOVITATES NO. 3524 Fig.1. DorsolateralandventralviewsofaparatypeofGonatodesalexandermendesi,AMNHR-151804, adultmale,SVL43mm.Throatcolorvariesfromyellowtobrightorange,butherewasperhapsdistortedby nembutalinjectionand/orphotographydoneundertheprotectionofablueraintarp.PhotographsbyC.J.C. G. alexandermendesi: midventral subcaudals followed by a divided midventral’’ (Avila- that are neither widened nor significantly Pires, 1995: 258, 262, fig. 84). differentfromadjacentscales;usually3lateral Finally, 12 species of Gonatodes have a row rowsofscalesdistallyonfingersandtoes;and ofsignificantlywidened,hexagonal,midventral usually 4 scales at the end of the toe subcaudalscales,asfoundinG.alexandermen- surrounding the claw. desi: G. albogularis (certain populations), G. Also, among the 18 previously recognized atricucullaris, G. caudiscutatus, G. ceciliae, G. species of Gonatodes, only one, Gonatodes concinnatus, G. falconensis, G. humeralis, G. annularis, often has 4 lateral rows of scales ocellatus, G. petersi, G. purpurogularis, G. distally on fingers and toes, as in G. alex- taniae,andG.vittatus.However,noneofthese andermendesi.However, G.annularislacksthe species has the elongate spine found on the elongate spine on the supraciliary flap found supraciliary flap of G. alexandermendesi, and in alexandermendesi and has significantly all 12 of them have usually 2 or 3 lateral rows different subcaudal scutellation. In annularis, ofscalesdistallyonthefingers andtoes,not 4 moderately enlarged midventral subcaudals asinG.alexandermendesi. tend to have ‘‘a repetitive sequence of two DESCRIPTIONOFHOLOTYPE: Forthefollow- single midventrals (one after the other) … ing description, we have followed the format 2006 COLE AND KOK: GEKKONID LIZARD FROMGUYANA 5 Fig. 2. Dorsal view of head of Gonatodes alexandermendesi, AMNH R-151804, paratype, showing elongate supraciliary spine over each eye (white arrowhead indicates right one on dark background). PhotographbyCarol R.Townsend. and methods of Avila-Pires (1995: 269–270) Limbs well developed. Tail round in cross for Gonatodes. Sphaerodactyline gecko, male, section, tapering toward tip. with snout–vent length (SVL) of 40 mm. Tail Rostral large, pentagonal, visible from length 22 mm, tip broken off, but distalmost above, with a median cleft extending forward 8 mm regenerated. Snout round, relatively from the posterior margin. Four postrostrals, wide, gently sloping toward top of head. lateralones(supranasals)distinctlylargerthan Neck slightly narrower than head and body. median ones, 1 median postrostral slightly Body nearly cylindrical but wider than high. larger than adjacent scales on snout. Nostril 6 AMERICAN MUSEUMNOVITATES NO. 3524 bordered by rostral, 4 postnasals, and lateral rather regular longitudinal rows, with 41 postrostral (supranasal), separated from first scales along the midventral line between supralabial by contact between rostral and anterior margin of forelimbs and vent. Scales lowermostpostnasal.Postnasalsaslargeas,or around midbody 93, of which 14 are ventrals. slightlylargerthan,adjacentloreals.Scaleson Scales on preanal plate similar to ventrals, snout and on loreal region roughly round, excepting border of vent, which has minute granular, juxtaposed. Loreal scales 11 (right scales. Male with small escutcheon area on side) or 12 (left) in a line between postnasals posterior abdomen between thighs and on and anterior margin of orbit. Scales decrease ventral surface of thighs. slightly in size toward posterior part of head. Scales dorsally on base of tail suddenly Scales on supraorbital region similar to and become flat, smooth, rounded in shape, continuous with those on top of head. imbricate (rather than conical). Underside of Supraciliary flap on anteriodorsal edge of eye tail with smooth, flat, imbricate scales, in- with a series of slightly enlarged scales (larger creasing in size toward midventral line; first 9 anteriorlythanposteriorly),formingasmooth small subcaudals posterior to vent on mid- to somewhat indented margin, with a very ventral row undistinguished but followed by elongatespineprojectingfrommiddleofupper 11significantlywidenedmediansubcaudalsin margin. Pupil round. Supralabials 6 (both a row on original part of tail; on regenerated sides), decreasing in size posteriorly, suture part, 16 extraordinarily wide median subcau- between numbers 5 and 6 (on right side) or dals in a row (up to 3 times width of adjacent scale number 5 (on left) being below center of scales). eye.Scalesontemporalregionsimilartothose Scalesonlimbsgranular,exceptinganterior on posterior upper part of head. Ear opening and ventral surfaces of thighs and ventral muchsmallerthaneye,obliquelyoval. surface of lower legs, where they are smooth, Mental large, roughly trapezoid, with later- flat,roundish,imbricate.Lamellaeunderthird al margins slightly concave, anterior and finger 22 (each side), of which 5 (right) or 6 posterior margins having an obtuse angle. (left) are slightly enlarged basal ones; under Postmentals 2, distinctly larger than adjacent fourth finger 21 (right) or 22 (left), with 6 posterior scales. Scales on chin small and (each side) slightly enlarged basal ones; under polygonal directly behind postmentals, gran- fourth toe 24 (each side), with 7 (each side) ular posteriorly; a few larger, polygonal somewhat enlarged. Fingers and toes with 4 scales adjacent to infralabials, juxtaposed. lateral rows of scales distally. Claws exposed, Infralabials6(rightside)or5(left),decreasing nonretractile, between two basal scales (1 in size posteriorly, number 4 (right side) or dorsal, 1 ventral). suture between numbers 4 and 5 (left) being Colorationinlife,fromfieldnotestakenon below center of eye. 9 March 1998: Dorsum dark reddish brown Scales on nape and sides of neck granular, through base of tail; rest of tail gray; dorsum continuous with those on head and body. with tiny irregular black markings; orange Scales on throat smooth, imbricate, with wash on side of face, around neck dorsally, roundposteriormargin,withshorttransition- and on anterior surface of arms; yellowish al area with granular scales on chin. orange beneath arms; venter gray, but throat Dorsals granular, on vertebral area similar bright orange, chest bright yellow. in size to scales on snout; dorsolaterally and Coloration in preservative, noted on 11 on flanks slightly larger and lacking small December 2005: Dorsal surfaces reddish groups of larger, conical scales along body, brown, darker above than below, with few including neck. Transition between scales on small dark brown spots, and, on sides, visible flanks and ventrals somewhat abrupt but not with magnification, very few tiny pale spots clearly demarcated. Ventral region with scales comprised of four or fewer granules (not distinctly larger than dorsals, smaller on chest enlarged); chin and throat pale yellow; below than on belly, smooth, hexagonal to rhom- original portion of tail, a pale midventral boidal but with rounded corners, imbricate; stripe with indistinct, irregular edges; below ventralsinobliquerows,onbellyalsoforming regenerated portion of tail, gray. 2006 COLE AND KOK: GEKKONID LIZARD FROMGUYANA 7 VARIATION IN THE PARATYPES FROM THE scales (Type B of Rivero-Blanco, 1979), those TYPE LOCALITY: In comparison with the de- onregeneratedpartoftailusuallymuchwider scription above, the five paratypes from the (2–3 times adjacent scales); number of lamel- type locality (AMNH R-151804 and R- lae under third finger 19–22 each side, with 5 151806–R-151809) vary as follows: 3 (instead or 6 basal ones enlarged each side; number of of 4) postrostrals, all larger than adjacent lamellae under fourth finger 20–24 each side, scales on snout (R-151804, R-151806, R- with 5–7 basal ones enlarged each side; 151807); 3 (instead of 4) postnasals (R- number of lamellae under fourth toe 21–26 151804, R-151806–R-151809); unclear wheth- each side, with 5–8 basal ones enlarged each ernostril contacts first supralabial (R-151807, side; fingers and toes with 4 lateral rows of R-151809);earopeningsubtriangularonright scalesdistallyonallspecimens,exceptAMNH side but left side obliquely ovalas in holotype R-151809,whichhas3or4(difficulttoseeon (R-151806, R-151808), suggesting shape may this, the smallest individual). not be fixed on individual. Colorationinlifewasnotedfortwoofthese The size of the very elongate supraciliary individuals in addition to the holotype. For spine is rather constant among the paratypes AMNH R-151804 (fig. 1), coloration was as and holotype, but there is variation in the described for the holotype except the dorsum extent and direction of its curvature. In wasgray,withbaseoftailgrayishbrown,rest comparison with the illustration of G. hase- of tail gray; yellowish orange was not seen mani in Avila-Pires (1995: 271, fig. 87), in beneath arms. For R-151808, dorsum was AMNH R-151804–R-151806 the spines are dark reddish brown, becoming grayish brown straighteryetcurvedsomewhatposteriorly.In on tail; no tiny irregular black markings seen; R-151807andR-151809thespineoneachside orange wash on side of face but yellowish is nearly straight. In R-151808 only the left orange around neck dorsally; venter gray but spine is nearly straight. The spines on pre- throat yellowish orange; chest orangish yel- served specimens can be flexed with a dissect- low; bright yellow beneath arms. ing tool, and perhaps they are flexible in life Coloration inpreservativewas notedforall also. six of these individuals on 11 December 2005, Mental with posterior margin slightly con- under magnification, and on most specimens cave (AMNH R-151806, R-151807). the chin and throat appeared pale yellow; Several tiny patches (4 scales or so) of males had no markings here, but the two inconspicuous but slightly enlarged, conical females (AMNH R-151806, R-151809) had scales, often light in color, on sides (AMNH from several to numerous dark brown spots R-151806, R-151809, the second of which has on the chin and throat. Also, on only the two some on base of tail also), visible with females, there was an inconspicuous thin light magnification. crescent dorsally crossing the neck and con- Additional data vary in the topotypes as necting on each side to the upper postocular follows: SVL 34–44 mm; number of loreals edge of the orbit; and on the neck, back, and 10–12 each side; number of enlarged suprala- sides, a few tiny patches (about 4 granules) of bials, 4–6 each side, with number 4 to suture very inconspicuous, pale areas in which some between numbers 5 and 6 being below center palegranulesaretallerthanadjacentones;this of eye; number of enlarged infralabials 4–6 was seen on the base of the tail in AMNH R- each side, with suture between numbers 3 and 151809 also. On all, the dorsum was light 4 to number 5 being below center of eye; brown to dark reddish brown, darker above number of scales around midbody 92–101, of than below, with or without darker brown which 11–14 are ventrals; number of scales spots, smudges, or mottling above; only on alongmidventrallinebetweenanteriormargin one female (R-151809), a broad paler brown of forelimbs and vent 41–44; after 7–9 small or tan vertebral area with a few darker undistinguishedsubcaudalsonmidventralline smudges in it. On most specimens, the mid- from vent, additional subcaudals on midven- ventral area of the original tail had a pale tral line of original tail usually significantly stripe with indistinct, irregular edges; regener- wider (about 1.3–1.5 times) than adjacent ated tail uniform gray below; but one (R- 8 AMERICAN MUSEUMNOVITATES NO. 3524 Fig.3. Dorsolateralviewsofamaleparatype(above,IRSNB2631,SVL44mm)andafemaleparatype 2006 COLE AND KOK: GEKKONID LIZARD FROMGUYANA 9 151808) had a small subcaudal white spot throat, and chest orangish yellow; chin whit- distally. ish; venter grayish approximately from arm Tongue (visible only in AMNH R-151804) insertion to vent; under magnification some fleshy, relatively wide, slightly narrowing isolated whitish granules, sometimes in tiny anteriorly with a rounded tip having a short paler patches (up to 4 granules) present on median cleft; tongue covered anteriorly with sides of neck and body in IRSNB 2631 and imbricate, scalelike papillae. 2636 but absent in IRSNB 2639; ventral VARIATIONINTHEPARATYPESFROMKAIETEUR surface of tail grayish, large median subcau- NATIONAL PARK: The 10 specimens (3 males, dals lighter proximally, darker distally; iris 5 females, 1 subadult, 1 juvenile; IRSNB gray. 2630–2639) collected in Kaieteur National In contrast to the topotypes, males from Park are morphologically similar to the speci- Kaieteur havea more yellowish throat (bright mens of Gonatodes alexandermendesi de- orange or yellowish orange in the topotypes), scribed above (fig. 3). Adult SVL varies from but this could be owing to seasonal variation 41 to 49.6 mm, the largest specimen being (breeding season) or geographic variation. amale.Thesubadultis31.9 mmSVL,andthe In contrast to other males, IRSNB 2636 has juvenile is 22.6 mm SVL. 3or4smallgrayishspotsonthroat,justabove Variation in scalation and coloration arm insertion (throat immaculate in other showed only negligible differences between males), and IRSNB 2631 had a short, thin, the two localities. For instance, 50% of the light collar on the neck (not visible in pre- specimens from the type locality have 3 servative). postrostrals (instead of 4 as in the holotype) Females are grayish brown with dark gray versus 70% of the specimens from Kaieteur or black spots on head and on each side of National Park; IRSNB 2637 has 7 enlarged a reddish brown vertebral area; a crescent- supralabials on each side (maximum of 6 in shaped light collar dorsally crosses the neck the topotypes), and a few specimens from and connects on each side to the upper Kaieteur National Park have 15 ventral rows postocular edge of the orbit; ventrally, head of scales across midbody (instead of 14), but and throat dirty brown with some darker as discussed above, there is some subjectivity longitudinal stripes and tiny spots; several in these characters also. Other data fall into larger black spots on throat; under magnifi- the range of variation of the topotypes. cation a few tiny patches (generally 1–5 As in the topotypes, the size of the very granules) of inconspicuous, pale areas, in elongate supraciliary spine is rather constant which some pale granules are taller than among the specimens from Kaieteur National adjacent ones, present on sides of neck and Park. This spine was mobile in life and was body, but 1 female (IRSNB 2632) has more sometimes observed flexed over the orbit in numerouspatchesinvolvingupto12granules; wet specimens. The spine is clearly visible but venter light brown to gray; large median very small in juveniles. subcaudals pinkish proximally, becoming Coloration in life was noted for almost all whitish distally, with several dark spots on individuals from Kaieteur National Park and sideoftail;irisreddish.Thesubadult(IRSNB reveals sexual dichromatism (fig. 3). Males 2635) and the juvenile (IRSNB 2638) have havedarkreddishbrowntograydorsum,with coloration and pattern very similar to the some small irregular black markings; tail has females, except that the distal part of the tail mostly the same coloration as dorsum; yel- of IRSNB 2638 has 14 alternating black and lowish wash on side of face, around neck white rings and a black tip. dorsally, and on anterior surface of arms; Coloration in preservative is similar to the yellow beneath arms; ventral part of head, topotypes except that IRSNB 2639, a male, r (below,IRSNB2630,SVL47mm)ofGonatodesalexandermendesifromKaieteurNationalPark,Guyana. PhotographsbyP.J.R.K. 10 AMERICAN MUSEUMNOVITATES NO. 3524 has a light pinkish coloration on the ventral part of the head. DISTRIBUTION (fig. 4): Known only from twolocalitiesinGuyana:thetypelocalityand Kaieteur National Park. The specimens from the type locality were found in the same span of time with one other species of Gonatodes (G. humeralis; N 5 12) and two other species ofgeckos,Pseudogonatodesguianensis(N53) and Thecadactylus rapicauda (N 5 16). Those at Kaieteur National Park were found with only one other species of gecko, G. humeralis, along the Tukeit Trail that runs between the Kaieteur airstrip and Tukeit Landing. NATURAL HISTORY: All specimens were collected in primary rain forest, those from Kaieteur National Park being from forest on white sand, between 400 and 420 m elevation. Details on habitat at Kaieteur National Park are given in Kok (2005). Most of these specimens were found around boulders, on Fig.4. MapofGuyanashowingthedistribution which they were sometimes active, escaping of Gonatodes alexandermendesi (triangle represents thetypelocality,circleKaieteurNationalPark). into cracks and crevices between rocks when disturbed. They were never found associated moist, cool locations between rocks or on the with bodies of water. lower parts of tree trunks. Most specimens Two specimens were collected on rocks: were found on objects above ground level but IRSNB2630,amale,wascollectedca.150 cm close to it, although an uncollected individual above the ground on a boulder; IRSNB 2633, wasobservedca.180 cmabovethegroundon a female, was collected ca. 100 cm above the aboulder. IRSNB 2633, a femalecollected on groundinacreviceonaboulder.IRSNB2631 9 November 2004 at 12:25 pm, contained 2 and 2636, both males, were collected in soft, whitish oval eggs measuring 4.15 3 buttress roots, adjacent to boulders. Two 3.34 mm, and 4.20 3 3.30 mm, respectively. females,IRSNB2632and2637,werecollected Anotherfemale,IRSNB2634,collectedonthe onrottenfallentreetrunks,bothofthemclose samedayat12:35pm,containedasinglesoft, to large rocks. IRSNB 2635, a subadult, was whitish oval egg measuring 4.72 3 3.57 mm. collected ca. 80 cm above the ground on Juveniles were observed in November and a vertical tree trunk; it moved around to the December, which at Kaieteur National Park other side of the trunk when disturbed, not coincides with the beginning of the short wet trying to escape by running vertically. Only season. one specimen, IRSNB 2634, a female, was As reported for several gekkonid taxa collected on the leaf litter. Two additional (Bauer et al., 1989; Watkins-Colwell and specimens,amale(IRSNB2639)andajuvenile Bauer, 2004), G. alexandermendesi is able to (IRSNB 2638), were collected in pitfall traps lose part of its skin without significant installedbeneathaplasticdriftfencealongthe bleeding or apparent significant injury, which trail. A few other specimens were observed in is typical in the antipredator strategy called the same microhabitats mentioned above but ‘‘regional integumentary loss’’ (Bauer et al., not collected. 1989). The same integumentary fragility was In Kaieteur National Park, G. alexander- observed by P.J.R.K. in G. annularis. To our mendesi was observed active only during the knowledge, this is the first record of this day, between 10:00 am and 3:00 pm, in low antipredator defense in the genus. populationdensity.Itisnonheliophilic,avoid- COMMENTS: ThetypelocalityofGonatodes ing sunny patches, and is found in shady, hasemani isVilla Bella, Rio Beni, Bolivia, and