Dactyloa insignis (Cope 1871)

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 : 32-34

Dactyloa insignis (Cope 1871)

Figures 2 ; 14; 18K–M.

Anolis microtus: Peters and Donoso-Barros (1970: in part.: referring to the holotype of Diaphoranolis brooksi ). Anolis insignis: Cope (1871, 1876); Boulenger (1885); Dunn (1937); Taylor (1956); Peters and Donoso-Barros (1970); Savage (1974); Myers (1977); Savage and Talbot (1978); Arosemena et al. (1992); Auth (1994); Martínez and Rodríguez (1994); Young et al. (1999); Ibáñez et al. (2001); Poe (2004); Hamad (2009); Fläschendräger and Wijffels (2009); Poe et al. (2009); Carrizo (2010); Jaramillo et al. (2010); Lotzkat et al. (2010b); Stadler (2010); Castañeda & de Queiroz (2011). Diaphoranolis brooksi: Barbour (1923) .

Holotype. Lost according to Savage and Talbot (1978); from Costa Rica: Provincia de San José: near Ciudad San José; probably from near La Palma (Savage 1974; Fig. 1 : loc. 21; Fig. 21 ).

Diagnosis. A large species (maximum SVL 160 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. casildae , D. frenata , D. ginaelisae , D. ibanezi , D. kunayalae , and D. microtus ). Dactyloa insignis can readily be distinguished from these six species by its unique coloration of fine reticulate lines forming transverse crossbands on dorsum and flanks, and a preaxillary dark blotch ( Fig. 14 ). Moreover, D. insignis has all dorsal and lateral body scales smooth (vs. conical, keeled, rugose or wrinkled in the other species), and the highest number of scales around midbody (190 or more vs. 178 or fewer). In addition, D. insignis differs from D. casildae , D. frenata , and D. ibanezi in having short legs (tip of fourth toe of adpressed hind limb reaching at most to a point between shoulder and tympanum in D. insignis ), and from D. ginaelisae , D. ibanezi , D. kunayalae , and D. microtus in having more subdigital lamellae under the fourth toe (52 or more in D. insignis vs. 50 or fewer) as well as under the fourth finger (40 in D. insignis vs. 37 or fewer).

Description. Total length to 464 mm; SVL to 160 mm in males, to 135 mm in females; tail long, about two times SVL, compressed, without dorsal crest; legs short, tip of fourth toe of adpressed hind limb reaching at most to a point between shoulder and tympanum; internasals, canthals, and loreals keeled; scales of frontal and prefrontal area mostly flat, smooth; IP usually distinct, surrounded by not much smaller scales (indistinct from surrounding scales in our juvenile); parietal eye usually distinct (barely visible in our juvenile); scales of SS barely enlarged, smooth; scales of supraorbital disk not conspicuously enlarged, smooth; two or three only slightly elongate, keeled anterior superciliary scales, none reaching a length of one-fourth of horizontal eye diameter; anterior sublabials distinctly enlarged, about as high as INL, keeled; scales of temporal arch conspicuously larger than those above and below; ear opening moderate to large, higher than SPL and INL together, slightly lower to higher than eye, much larger than IP; nuchal and dorsal crests present; 0–2 rows of smooth middorsal scales slightly enlarged; other dorsal scales as well as lateral scales flat, smooth; ventrals much larger than largest dorsals, smooth; scales on anterodorsal surface of thigh mostly smooth, only on anterior edge unicarinate with a few bi- or tricarinate; scales on dorsal surface of forearm smooth, becoming unicarinate towards wrist and anterior edge; fourth toe with well-developed dilated pad, about three times width of distal phalanx; female dewlap moderate, extending posteriorly to slightly beyond axilla, with broad, diffuse gorgetal-sternal rows leaving very narrow interspaces with less densely packed scales.

The hemipenis of Dactyloa insignis remains undescribed.

Coloration in life. Dorsal and lateral surfaces white to brown; dorsum, flanks, limbs, and tail with fine reticulate lines conglomerating to form light-centered crossbands that become solid only on posterior portion of tail; lips with dark vertical bars; a pronounced, light-centered blotch between tympanum and axilla, and a dark postorbital stripe extending to above tympanum; ventral surfaces largely white, except for dark crossbands forming complete rings under tail and dark flank markings and lip bars extending onto ventral surfaces; iris brown; female dewlap brown, with dark and light blotches and lines ( Figs. 2 ; 14). Dactyloa insignis exhibits considerable metachrosis with ground color ranging from white to dark brown, and the dark markings being green, brown, or almost black. Most notably, in certain situations numerous beige to orange blotches appear on body and head, and even the color of the iris can range from almost white to dark reddish brown (compare Figures 14 B, C, and F). Color photographs of D. insignis have been published by Savage (2002), Köhler (2003, 2008), Fläschendräger and Wijffels (2009), Stadler (2010), and Uetz (2013).

The coloration in life of the adult female (SMF 89482, Figs. 2 ; 14B–D, F, G) was recorded as follows: Ground color Sulphur Yellow (57) with Sepia (219) broken crossbands on dorsum which contain Pale Pinkish Buff (121D) blotches; vertical series of Salmon Color (106) blotches between crossbands; several Spectrum Orange (17) blotches on neck; a Raw Umber (23) postorbital stripe; a Burnt Umber (22) blotch with Raw Umber (23) center anterior to shoulder; tail with Sepia (119) crossbands, anterior ones suffused with Natal Brown (219A); ventral surfaces of body and tail dirty white; Dorsal surfaces of limbs with Dark Brownish Olive (129) and Lime Green (59) transverse lines as well as transverse series of Pale Pinkish Buff (121D) flecks; iris Cinnamon-Rufous (40); dewlap Sayal Brown (223C) with Indigo (73) horizontal lines and horizontal series of dirty white flecks. The coloration in life of the juvenile female (SMF 91477, Figs. 2 ; 14A, E, H–L) was recorded as follows: Dorsal ground color Opaline Green (162D), grading into dirty white with a suggestion of Pale Horn Color (92) ventrolaterally; head and body with a reticulum of fine Sepia (119) lines that are suffused with, and partly turn into, Emerald Green (163), reach onto venter and accumulate along middorsum to give the impression of four blotches; limbs, toes, and fingers with pairs of transverse Sepia (119) lines; tail with six Sepia (119) transverse bands, the anterior three composed of dense reticula of lines similar to the middorsal blotches; head, body, and limbs with irregularly distributed Orange-Rufous (132C) and Cream Color (54) blotches; ventral ground color dirty white with a suggestion of Pale Horn Color (92); iris Pale Pinkish Buff (121D); tongue Olive-Gray (42); dewlap dirty white with a suggestion of Pale Horn Color (92) at base, grading into Ground Cinnamon (239) mottled with Buff (24) towards apex, with Sepia (119) longitudinal lines, longitudinal series of dirty white spots, and a Pale Horn Color (92) margin.

Coloration in preservative. After 23–48 months of preservation in 70% ethanol, the ground color has lightened to dirty white, and all markings have assumed grayish or brownish tonalities. Only slight suggestions of blue where green was present in life in our juvenile are still discernable after 23 months ( Figs. 18 K–M).

Geographic distribution. Dactyloa insignis is distributed throughout Costa Rica and Panama at low and premontane elevations of 0–1600 m asl. In Panama, the species has been recorded from the provinces of Bocas del Toro, Chiriquí, Coclé, Colón, Darién, Panamá, and Veraguas, and from the Comarca Ngöbe-Buglé ( Fig. 21 ). According to Young et al. (1999), it is also present in the Comarca Kuna Yala.

Natural history notes. Both specimens were encountered at night while they were sleeping on branches 5–6 m above ground. Around our collection sites, Dactyloa insignis co-occurs with D. frenata , D. ibanezi , and D. kunayalae .

Our automatized temperature recordings around our collection sites of Dactyloa insignis (640 and 880 m asl) range between 18.2–26.2°C. According to our combined dataset of 36 georeferenced occurrences, the species inhabits LMF, LWF, PMMF, and PMWF, with temperatures between 12.4–33.7°C, mean annual temperatures of 18.0–26.4°C and a total annual precipitation of 1696–4373 mm.

Conservation. Jaramillo et al. (2010) calculated an EVS of 11 for Dactyloa insignis , and assigned the species to the IUCN category LC. We calculated the species’ EVS as 4 (range) + 3 (persecution) + 4 (ecological distribution) = 11. Its extent of occurrence of more than 63000 km 2 does not qualify D. insignis for any of the “Threatened” IUCN categories. Considering the continuing deforestation we observed in the region, we place the species in the category “Near Threatened” (NT).

Remarks. Our record from Willie Mazú ( Fig. 1 : loc. 9) constitutes the first record for the Comarca Ngöbe- Buglé. In the maps of Köhler (2003, 2008), the distribution area of Dactyloa insignis extends into Colombia. Although it is very likely that the species ranges at least into the Colombian Darién, no specimens from this country are known to date. The occurrence of D. insignis in the Comarca Kuna Yala as stated by Young et al. (1999) seems plausible considering that the specimen FMNH 170087 was collected at Paradise Camp, which lies less than 4 km west of Camp Summit ( Fig. 1 : loc. 20) that is situated on the border between Darién province and the Comarca Kuna Yala.

Unfortunately, our sample is composed of just two females. Savage (2002) pictured male individuals from Monteverde in Costa Rica (plates 256 and 257), and described the male dewlap as dark red (key on p. 451) or as “primarily orange-red, with or without several horizontal green or white bars and dark spotting” (p. 455) with a white to greenish free margin.

Both Savage (2002) and Köhler (2008) stated that Dactyloa insignis has 51 or more lamellae under the fourth toe, and used this as a key characteristic to distinguish this species from D. microtus , which has at most 49 according to these authors. Nevertheless, Savage and Talbot (1978) counted just 50 lamellae on the fourth toe of MCZ 16297, a value that is also reached by one of our specimens of D. ginaelisae (which formerly was included in D. microtus ). All previous authors have reported the presence of a distinct IP and parietal eye as a diagnostic character to distinguish D. insignis from D. microtus . However, the IP is indistinct and the parietal eye barely visible in one of our two specimens ( Fig. 14 H), suggesting that strict adherence to this key characteristic might not always be recommendable (also see remarks concerning this matter for D. ginaelisae and D. microtus ).

Savage and Talbot (1978) pointed out differences in anterior head scale surface and coloration between individuals from Costa Rica and Pacific west-central Panama on the one hand and examples from northwestern, central, and eastern Panama on the other hand, concluding that additional material was required to finally evaluate whether or not two species are involved. Our specimens have smooth anterior dorsal head scales and, just as the individuals photographed by Michael Castillo in Donoso district in Colón province, agree in exhibiting dark lip bars, a dark postorbital marking (in form of a short stripe rather than a spot or blotch), a dark preaxillary blotch, and in having their transverse bands formed by reticula. Thus, our specimens would fall somewhere between Savage and Talbot’s (1978) specimens from Costa Rica and their specimen from Valle de Antón (Coclé province). Since we have no male from our study area available, we cannot contribute further to the issue of geographical variation in male dewlap coloration.

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 14. Female specimens of Dactyloa insignis from western Panama: (A) juvenile female SMF 91477 from Willie Mazú; (B) adult female SMF 89482 from Cerro Mariposa at daytime, and (C) at night immediately after capture; (D – E) dewlaps of (D) SMF 89482 and (E) SMF 91477; (F) lateral and (G) dorsal views of head of SMF 89482; (H) dorsal and (I) ventral views of head of SMF 91477; ventral views of (J) entire specimen, (K) left foot, and (L) right hand of SMF 91477.

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 21. Distribution of Dactyloa ibanezi and D. insignis 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 (*).