Dactyloa casildae

Lotzkat, Sebastian, Hertz, Andreas, Bienentreu, Joe-Felix & Köhler, Gunther, 2013, Distribution and variation of the giant alpha anoles (Squamata: Dactyloidae) of the genus Dactyloa in the highlands of western Panama, with the description of a new species formerly referred to as D. microtus, Zootaxa 3626 (1), pp. 1-54 : 23-27

Dactyloa casildae (Arosemena, Ibáñez and de Sousa 1992)

Figures 2 ; 10–11; 17A–C; 18A–D.

Anolis casildae: Arosemena et al. (1992) ; Auth (1994); Young et al. (1999); Hofer and Bersier (2001); Ibáñez et al. (2001); Nicholson et al. (2001, 2005); Hamad (2009); Fläschendräger and Wijffels (2009); Carrizo (2010); Chun (2010); Jaramillo et al. (2010); Stadler (2010); Castañeda & de Queiroz (2011).

Holotype. MVUP 755, male, from Quebrada Frank, 1100 m, 8°44’N, 82°13’W, Reserva Forestal de Fortuna, Chiriquí province, Panama ( Fig. 1 : loc. 29; Fig. 20 ).

Diagnosis. A large species (maximum SVL 114 mm) of the genus Dactyloa (sensu Nicholson et al. 2012) that is most similar in external morphology to the other members of this clade found in western Panama ( D. frenata , D. ginaelisae , D. ibanezi , D. insignis , D. kunayalae , and D. microtus ). Dactyloa casildae can readily be distinguished from these six species by its coloration (described below, shown in Figs. 2 , 10 , and 11), and from all except D. ibanezi by its very long tail (more than 2.5 times SVL). Moreover, D. casildae differs from D. ginaelisae , D. insignis , D. kunayalae , and D. microtus in having long legs (tip of fourth toe of adpressed hind limb reaching to eye or beyond, usually to nostril or beyond, in D. casildae vs. at most to posterior border of eye), and from D. ginaelisae , D. insignis and D. microtus in having more horizontal loreal rows (6 or more in D. casildae vs. 5 or fewer). Additionally, D. casildae has more subdigital lamellae under the fourth toe (42 or more in D. casildae vs. 41 or fewer) as well as under the fourth finger (29 or more in D. casildae vs. 28 or fewer) than D. ibanezi and D. kunayalae .

Description. Total length to 446 mm; SVL to 114 mm in males, to 99 mm in females; tail very long, about 2.5–3 times SVL, compressed (only very slightly in many individuals), without dorsal crest; legs long, tip of fourth toe of adpressed hind limb reaching at least to eye, in most individuals well beyond eye, and in some even beyond snout; internasals, canthals, and loreals keeled; scales of frontal and prefrontal area mostly keeled, some rugose or almost smooth (especially in juveniles); IP distinct, surrounded by smaller, keeled scales; parietal eye distinct; scales of SS enlarged, keeled; scales of supraorbital disk distinctly enlarged, keeled; a very elongate (in several specimens two, rarely three, accordingly shorter scales), keeled anterior superciliary scale, more than half as long (in some specimens almost as long) as horizontal eye diameter, usually followed by up to three similarly keeled but much shorter scales; anterior sublabials slightly enlarged, but never as high as INL, keeled; temporal arch weakly defined, with enlarged scales usually only in its anterior portion; ear opening large, higher than SPL and INL together, at least as high as eye, much larger than IP; nuchal and dorsal crests present in males; 2 rows of keeled middorsal scales slightly enlarged only in few specimens; other dorsal scales as well as lateral scales granular, conical to keeled; ventrals larger than largest dorsals, smooth; scales on anterodorsal surface of thigh mostly unicarinate, some bi- or tricarinate; scales on dorsal surface of forearm unicarinate, becoming multicarinate towards wrist; fourth toe with well-developed dilated pad, about three times width of distal phalanx; male dewlap very large, extending posteriorly to halfway between axilla and groin in large specimens, with well-demarcated gorgetal-sternal scale rows of densely arranged scales and widely spaced scales in the broad interspaces between the rows; female dewlap moderate, extending posteriorly to slightly beyond axilla, with more diffuse gorgetalsternal rows owing to the less widely spaced scales in their interspaces.

The completely everted hemipenis of SMF 91454 ( Figs. 17 A–C) is a small, bilobate organ; sulcus spermaticus bordered by well-developed sulcal lips, opening at base of apex into two broad concave areas, one on each lobe; an asulcate ridge present; a knob-like processus present on asulcate side of truncus; lobes finely calyculate, truncus with transverse folds.

Coloration in life. Dorsal and lateral surfaces green to bluish green, either almost unicolor, or with brown, blue, and yellow spots or blotches, or additionally with oblique transverse bands that may appear solid or composed of blotches; some females of the unicolor and spotted variants with a dark-bordered light middorsal stripe; blue and yellow mottling usually most contrasting around chin, gular area, throat, and shoulders; light and dark lip bars often present; usually a postorbital stripe with dark borders; postorbital stripes of both sides often vaguely connected by a diffuse nuchal band; a less prominent preorbital stripe extending to snout in many specimens; tail with dark mottling suggesting diffuse crossbands; ventral surfaces unicolor yellow or yellowish green, in some individuals with dark mottling; iris brown; male dewlap cream-colored with gorgetal-sternal rows of yellow scales and interspersed blue or green scales, scales in interspaces between gorgetal-sternal rows widely spaced; female dewlap with contrasting yellow and green or blue mottling suggesting longitudinal stripes or a reticulate pattern, with only weakly demarcated gorgetal-sternal rows ( Figs. 2 ; 10–11). Apart from the extremely variable color pattern, Dactyloa casildae is capable of considerable metachrosis (compare Figs. 10 A and I, or 10E and F). While the description above refers to the colorful or green phase usually shown while the animal is sleeping, the dark or brown phase, typically assumed when the animal is handled, can cause all colors to turn dark brown, making most or all elements of a possible spotted or banded pattern disappear. Specimens spotted at daytime showed either of the color phases. Color photographs of D. casildae have been published by Köhler (2003, 2008), Hamad (2009), Fläschendräger and Wijffels (2009), and Chun (2010).

The coloration in life of a subadult male (MHCH 2121, Figs. 9 B, J) was recorded as follows: Dorsal and lateral ground color Apple Green (61); body with a series of broad transverse Greenish Olive (49) bands, interrupted by a Buff-Yellow (52) reticulate mottling covering dorsal and lateral surfaces of body, and mottled with Dark Grayish Brown (20); dorsal surface of head densely mottled with Buff (124) and Sepia (219); lateral and ventral surfaces of head Robin’s Egg Blue (93) mottled with Spectrum Yellow (55); a Sulphur Yellow (57) postorbital stripe bordered by Sepia (219) extending from eye to above ear opening; chin region with a Sulfur Yellow (157) reticulate mottling bordered by Sepia (119); dorsal surfaces of limbs and base of tail with Greenish Olive (49) mottling forming transverse bands; posterior portion of tail Citrine (51) with mostly ill-defined Sepia (219) transverse bands; ventral surface of body Cream Color (54) mottled with Citrine (51) and a suggestion of Lime Green (59); ventral surfaces of limbs and base of tail Citrine (51) mottled with Cream Color (54) and Lime Green (59); iris Clay Color (26); dewlap with a continuum of the chin coloration in anterior portion, grading into Pale Horn Color (92) longitudinal lines of scales suffused with Leaf Green (146); dewlap skin between these lines Lime Green (59) with solitary Leaf Green (146) scales; dewlap margin Cream Color (54).

The coloration in life of an adult male (SMF 89455) was recorded as follows (translated from Hamad 2009): Dorsal surfaces with alternating crossbands from anterior head to tip of tail; transverse bands Yellowish Olive- Green (50), alternating with Olive-Yellow (52) bands with Straw Yellow (56) mottling, which grade into Turquoise Blue (65) and Straw Yellow (56) laterally; dorsal surface of head Spectrum Yellow (55), Greenish Olive (49), and Paris Green (63); lateral surfaces of head Spectrum Yellow (55), Turquoise Blue (65), and Sulphur Yellow (57), extending over ventral surfaces of head and body posteriorly to midventer; then grading into Beige (219D) that continues to ventral surface of base of tail; tail thereafter with Sepia (219) and Raw Umber (23) crossbands; dewlap Cream (84) with longitudinal Orange-Yellow (18) stripes and Cerulean Blue (67) scales.

Coloration in preservative. After 21–48 months of preservation in 70% ethanol, all green and blue elements have turned to brown or, especially around head, to bluish gray; yellow throat markings are dirty white to yellowish brown ( Figs. 18 A–D). After 10 years (SMF 85370), also the bluish shades have vanished almost completely.

Geographic distribution. As currently understood, Dactyloa casildae is an endemic of the Panamanian Cordillera Central in Chiriquí province and the Comarca Ngöbe-Buglé. The species ranges from the eastern extreme of the Serranía de Talamanca at Cerro Guayabo (RFLF, Chiriquí) and nearby BPPS (Comarca Ngöbe- Buglé) over 60 airline km east to Cerro Santiago. It occurs on both Caribbean and Pacific slopes, at premontane and lower montane elevations of 990–1720 m asl ( Fig. 20 ).

Natural history notes. All collected specimens were encountered at night while they were sleeping on branches, lianas, or leaves 0.3–4 m above ground. Hamad (2009) spotted individuals of this species sleeping as high as 8 m above the Río Hornito at RFLF. The only two individuals seen at daytime were perched head down on treetrunks 1.5 and 5 m above ground, respectively. During some surveys, Dactyloa casildae appeared very abundant at certain localities both at RFLF and Cerro Santiago in the Comarca Ngöbe-Buglé, with many sleeping individuals encountered very close to each other in some nights. In these surroundings, we also found this species to occur syntopically with D. ginaelisae , and in one case even to share a sleeping branch with that species. At the lowest collection site at Río Hacha, we found D. casildae to occur in syntopy with D. kunayalae .

Our automatized temperature recordings at collection localities of Dactyloa casildae (990–1560 m asl) range between 12.6–23.1°C. According to our combined dataset of 41 georeferenced occurrences, the species inhabits PMWF and LMWF, with temperatures between 11.8–27.4°C, mean annual temperatures of 17.8–21.2°C and a total annual precipitation of 2385–3376 mm.

Conservation. Jaramillo et al. (2010) calculated an EVS of 13 for Dactyloa casildae , and assigned the species to the IUCN category NT. We calculated the species’ EVS as 5 (range) + 3 (persecution) + 4 (ecological distribution) = 12. Its extent of occurrence of just 426 km 2 and the continuing deforestation we observed in the region qualify D. casilde for the IUCN category “Endangered” (EN).

Remarks. Our records expand the known range about 56 km southeastwards and 320 m uphill from previously reported localities (Nicholson et al. 2001; Chun 2010). Hofer and Bersier (2001) and consequently Nicholson et al. (2001) stated the westernmost specimens from BPPS to come from Bocas del Toro province. However, the region in question ( Fig. 1 : loc. 27) is presently situated within the Comarca Ngöbe-Buglé. As far as we know, Dactyloa casildae has not been reported from Bocas del Toro yet. Based on a sample of eight specimens, Nicholson et al. (2001) restricted the color morphs without transverse bands to females. Among our sample, there are also male specimens which exhibit a non-banded pattern ( Figs. 10 G; 11E), just like the specimen LACM FS 1084 pictured by Chun (2010: Fig. 4 ). Likewise, the middorsal stripe ( Fig. 10 C) is not present in all specimens, not even in all females, that lack transverse bands ( Fig. 10 D). One of our adult male specimens (SMF 89673, Figs. 10 A, I, Q) has no enlarged postcloacal scales. The same is true for the young male MHCH 2121 ( Figs. 10 B, J; 18A, B), that was erroneously pictured as a female by Köhler (2008: p. 99: Fig. 197) and could only be confidently sexed by verifying the presence of testes through an incision in the flanks. Considering the lack of postcloacal scales in some males, we assume that those allegedly female specimens having a chiefly white dewlap similar to the male dewlap (Nicholson et al. 2001) are actually males lacking enlarged postcloacal scales, whereas the female dewlap in reality always is contrastingly mottled.

Figures

FIGURE 1. Collection localities of Dactyloa specimens in western Panama (main map) and Lower Central America (inset). Black circles represent examined specimens and reliable photo records listed in the Appendix, gray circles stand for other localities that are mentioned in the text. One symbol may summarize several localities close to each other. See text for abbreviations and details. (1) Río Changena; (2) Bajo Mono, Sendero La Cascada; (3) Alto Chiquero; (4) Sendero El Pianista, Casa de Calixto; (5) Sendero Pianista, 1500 m; (6) Cerro Guayabo; (7) headwaters of Río Chiriquí Malí; (8) Quebrada Arena; (9) Willie Mazú; (10) Cerro Pata de Macho; (11) Cerro Saguí; (12) Río Flor; (13) Río Hacha; (14) W slope Cerro Santiago, La Nevera; (15) E slope Cerro Santiago, Quebrada Ardilla; (16) Cerro Mariposa; (17) Cerro Negro; (18) Río Chilagres; (19) Distrito de Donoso: between Botija, Brazo, Petaquilla, and Rio del Medio; (20) Camp Summit; (21) La Palma; (22) Cerro Dantas; (23) Parque Nacional Tapantí; (24) Sendero Quetzales on N slope Volcán Barú, 7000 ft = 2130 m; (25) Cerro Horqueta; (26) Boquete; (27) BPPS, transect of Hofer and Bersier (2001); (28) Smithsonian station at RFLF; (29) Quebrada Frank; (30) road to Almirante, 400 m; (31) PNGDOTH north of El Copé; (32) Valle de Antón; (33) Altos de Campana; (34) Isla Barro Colorado; (35) Nusagandí.

FIGURE 2. (A) Maximum likelihood consensus tree of 19 Panamanian anoles. Black bars demarcate smallest well-supported clusters. (B) Sampled individuals in life, with locality numbers referring to Fig. 1. (C) Taxonomic identity derived from morphology on the basis of available literature.

FIGURE 4. Variation in selected morphological characters among our sample of Dactyloa from western Panama, separated by males (circles, left) and females (triangles, right) for each lineage. See text for details.

FIGURE 9. Specimens of Dactyloa ginaelisae from Chiriquí and the Comarca Ngöbe-Buglé: (A) adult male MHCH 2237 from RFLF; (B) female SMF 89501 from RFLF in sleeping position and (C) the next day; (D) female SMF 91503 from Cerro Saguí in sleeping position and (E) the next day; (F) female SMF 89497 and (G) female MHCH 2234 from La Nevera; (H) uncollected female juvenile and (I) uncollected female from La Nevera; (J – M) dewlaps of (J) adult male SMF 89738 from RFLF, (K) male juvenile SMF 89737 from PNVB, (L) female SMF 89499 from RFLF, and (M) female SMF 89501; (N) lateral, (O) dorsal, and (P) ventral views of head of SMF 89501; (Q) ventral view of MHCH 2234; (R) enlarged postcloacal scales of SMF 89738; ventral views of (S) left foot and (T) left hand of male holotype SMF 91504 from Cerro Saguí.

FIGURE 10. Specimens of Dactyloa casildae from RFLF, Chiriquí (if not otherwise mentioned from western slope of Cerro Pata de Macho): (A) adult male SMF 89673 in sleeping position; (B) subadult male MHCH 2121; (C) female SMF 89458; (D) female MHCH 2120; (E) female juvenile MHCH 2123 in sleeping position and (F) the next day; (G) uncollected adult male exhibiting brown phase at night; (H) female juvenile MHCH 2127 in sleeping position; (I – L) dewlaps of (I) adult male SMF 89673, (J) subadult male MHCH 2121, (K) female SMF 90098 from Cerro Guayabo, and (L) female juvenile MHCH 2127; (M) lateral, (N) dorsolateral, and (O) ventral views of head of SMF 89458; cloacal regions of (P) uncollected male shown in G showing enlarged postcloacal scales, and of (Q) male SMF 89673 lacking enlarged postcloacal scales; (R) left foot and (S) left hand of SMF 89673.

FIGURE 17. Hemipenes of Dactyloa from western Panama: (A – C) Dactyloa casildae, SMF 91454: (A) sulcate, (B) asulcate, and (C) lateral view; (D – F) Dactyloa frenata, SMF 89467: (D) sulcate, (E) asulcate, and (F) lateral view; (G – I) Dactyloa ginaelisae, SMF 89498: (G) sulcate, (H) asulcate, and (I) lateral view; (J – L) Dactyloa ibanezi, MHCH 2184: (J) sulcate, (K) asulcate, and (L) lateral view; (M – O) Dactyloa kunayalae, SMF 91484: (M) sulcate, (N) asulcate, and (O) lateral view; all scale bars equal 1 mm.

FIGURE 18. Preserved specimens of Dactyloa from western Panama: (A – D) Dactyloa casildae, (A) and (B) young male MHCH 2121, SVL = 69 mm; (C) and (D) female SMF 89453, SVL = 81 mm; (E – G) D. frenata, (E) male SMF 89467, SVL = 132 mm, (F) and (G) young male SMF 91460, SVL = 72 mm; (H – J) D. ibanezi, (H) male paratype SMF 89459, SVL = 78 mm, (I) and (J) female SMF 91475, SVL = 78 mm; (K – M) D. insignis, (K) adult female SMF 89482, SVL = 124 mm, (L) and (M) juvenile female SMF 91477, SVL = 64 mm; (N – Q) D. kunayalae, (N) and (O) male SMF 91484, SVL = 103 mm; (P) and (Q) young female SMF 91485, SVL = 64 mm; (R) and (S) D. ginaelisae, female SMF 91503, SVL = 100 mm; (T) and (U) D. microtus, young male SMF 91499, SVL = 65 mm.

FIGURE 20. Distribution of Dactyloa casildae and D. frenata in western Panama (main map) and Lower Central America (inset). Localities of specimens with 16 S barcodes included in the molecular analyses are marked with an asterisk (*). Records of D. frenata from Colombia, such as the type locality, are not shown.