Sphaerodactylus verdeluzicola DÍAZ-LAMEIRO, VILLAMIL, GAMBLE, PINTO, HERRERA-MARTÍNEZ, THOMAS, BERNSTEIN, TITUS-MCQUILLAN, NIELSEN, AGOSTO-TORRES, PUENTE-ROLÓN, BIRD-PICÓ, OLEKSYK, MARTÍNEZ-CRUZADO & DAZA, 2022
Can you confirm these amateur observations of Sphaerodactylus verdeluzicola?
|Higher Taxa||Sphaerodactylidae, Gekkota, Sauria, Squamata (lizards: geckos)|
|Common Names||E: Puerto Rican Karst Gecko|
Spanish: Salamanquita de Monte y Mar
|Synonym||Sphaerodactylus verdeluzicola DÍAZ-LAMEIRO, VILLAMIL, GAMBLE, PINTO, HERRERA-MARTÍNEZ, THOMAS, BERNSTEIN, TITUS-MCQUILLAN, NIELSEN, AGOSTO-TORRES, PUENTE-ROLÓN, BIRD-PICÓ, OLEKSYK, MARTÍNEZ-CRUZADO & DAZA 2022|
Sphaerodactylus klauberi Cluster I — THOMAS & SCHWARTZ 1966
Sphaerodactylus klauberi — THOMAS & SCHWARTZ, 1975
Sphaerodactylus klauberi SCHWARTZ & HENDERSON 1991
Sphaerodactylus klauberi RIVERO 1998
Sphaerodactylus klauberi RIVERO 2006
Sphaerodactylus spp. DÍAZ-LAMEIRO et al. 2013
Sphaerodactylus klauberi Northwest clade — DAZA et al. 2019
Type locality: Puerto Rico, Rincón, Playa Domes, near the former Boiling Nuclear Superheater Reactor Facility, now Museo Tecnológico Dr. Modesto Iriarte, on the foothills of the mountain behind Road 4413 (18.3638808, –67.2679138) in Barrio Puntas, elevation of 9.4 m.a.s.l.,
|Types||Holotype. MPM-RA34016 (Fig. 2C–D), adult male, 30 June 2016. Paratypes. MPM-RA34017, female (Fig. 2A–B), from the same locality along with the holotype; MPM-RA34018, female (Fig. 2E–F), MPM-RA34019, male (Fig. 2G–H), Bosque Estatal de Río Abajo, 18.3331028, –66.7169458, 2015.|
|Diagnosis||Diagnosis: Sphaerodactylus verdeluzicola was formerly considered a small morphological variant within S. klauberi (Cluster I in Thomas and Schwartz ). This species is genetically divergent (Fig. 4) from the high elevation populations restricted here to S. klauberi sensu stricto along its distributional range (Fig. 1; D ́ıaz-Lameiro et al., 2013; Daza et al., 2019). Sphaerodactylus verdeluzicola can be distinguished from all congeners by the following characters: (1) size (median SVL = 21.50 mm), (2) smooth to partially keeled pectoral scales that are round to rhomboid in shape and either juxtaposed or slightly overlapping, (3) a distinctive clubshaped light cephalic figure, (4) a dark pentagonal parietal patch, (5) a short, steeply inclined nasal process in the premaxilla, (6) a large clavicular fenestra, and (7) a clavicular foramen near the anterior edge.|
Externally, S. verdeluzicola can be easily differentiated from congeners from Puerto Rico, especially the four species with potentially overlapping ranges: Sphaerodactylus klauberi Grant 1931, Sphaerodactylus nicholsi Grant 1931, Sphaerodactylus grandisquamis guarionex Thomas and Schwartz 1966, and Sphaerodactylus grandisquamis ateles Thomas and Schwartz 1966. In size, it is significantly smaller than high elevation S. klauberi (median SVL = 21.50 mm versus 30.83 mm in S. klauberi, W = 910, P = 4.133e–10; Fig. 5), S. grandisquamis, and S. roosevelti, although its proportions are similar to other low elevation Sphaerodactylus such as S. gaigeae, S. nicholsi, and S. townsendi.
Sphaerodactylus verdeluzicola can be differentiated from S. roosevelti and S. grandisquamis in the lack of sexual dimorphism and smaller size (Daza et al., 2019). Sphaerodactylus verdeluzicola differs from S. g. guarionex Thomas and Schwartz 1966 in that S. verdeluzicola displays a less marked, lighter, and more diffuse scapular patch. Sphaerodactylus verdeluzicola is also smaller in size than S. g. guarionex (SVL . 30 mm). Additionally, the pectoral scales are faintly keeled or smooth in S. verdeluzicola (Fig. 6) and keeled in S. g. guarionex, and the nuchal patch or patches are never continuous with the scapular patch in S. verdeluzicola. Unlike S. g. guarionex, S. verdeluzicola does not display a series of longitudinal dark lines on the dorsum. Sphaerodactylus verdeluzicola differs from S. g. ateles in that it is smaller than S. g. ateles (SVL . 30 mm) and lacks keeled gular scales. The distinctive head and scapular pattern of S. verdeluzicola is consistently present in both males and females (Figs. 2, 3), while S. g. ateles are sexually dimorphic. The ocelli on the scapular patch of S. verdeluzicola are clearly differentiated from the ground color and surrounded by dark lines laterally. The throat of S. verdeluzicola lacks the yellow-orange throat coloration of male S. g. ateles and the distinctive longitudinal lines on the dorsum of the body of female S. g. ateles.
Sphaerodactylus verdeluzicola is similar in appearance and proportions to species from low elevations that have a lighter brown or cream colored dorsum with scattered dark scales, namely S. nicholsi, S. townsendi, and S. gaigeae, the first of these being sympatric with S. verdeluzicola. Sphaerodactylus verdeluzicola differs from S. nicholsi in that S. verdeluzicola displays a light, club-shaped cephalic figure (Figs. 2, 3). In addition, S. nicholsi has a well-defined crescent-shaped dark mark on the parietal region (Thomas and Schwartz, 1966; Schwartz and Henderson, 1991; Rivero, 1998), while S. verdeluzicola displays a solid triangle or pentagon. Color pattern characters also differentiate S. verdeluzicola from S. townsendi, which has a fragmented pattern of dark patches on the head, and from S. gaigeae, which has a ribbon-shaped mark on it (Figs. 2, 3). Sphaerodactylus verdeluzicola has a more marked, darker scapular patch with fewer dark blotches on the dorsum compared to S. gaigeae (white patches surrounded by dark blotches in the back in S. gaigeae; Thomas and Schwartz, 1966; Schwartz and Henderson, 1991; Rivero, 1998), as well as more defined light transverse and dorsolateral lines compared to S. gaigeae, which has more chevron-like tail markings.
Another species that occurs geographically closer to S. verdeluzicola, although restricted to Desecheo Island, is S. levinsi. Sphaerodactylus verdeluzicola differs from this species in not having a well-defined dot in the parietal region and the scapular patch less defined, which in S. levinsi entirely encloses two ocelli.
Sphaerodactylus verdeluzicola is typically lighter in coloration than S. klauberi. In addition, it can be distinguished from S. klauberi by a characteristic light-colored cephalic figure resembling a club-shaped marking and a dark brown, pentagonal, parietal patch (Figs. 2, 3). Sphaerodactylus klauberi from El Yunque also have rhomboid pectoral scales, but they are more elongated and have keels that are more defined (raised) than in the R ́ıo Abajo populations of S. verdeluzicola (Fig. 6). Since the number of pectoral scales between the armpits is similar in all the specimens (18–19), scale morphological differences may result from allometric changes. Sphaerodactylus verdeluzicola and S. klauberi can also differ in the shape of the snout and the clavicular fenestra. In S. verdeluzicola (Fig. 7A–C), the lateral view of the snout is proportionally shorter and more steeply inclined than in S. klauberi (Fig. 7D–F). The differences in snout shape are mainly due to the ascending nasal process, which in S. verdeluzicola expands halfway along its length and tapers gradually to end in a rounded tip (Fig. 7A). In S. klauberi, this process tapers gradually (without the expansion) along its entire length, ending in a point (Fig. 7D). The clavicular fenestra in S. klauberi and S. verdeluzicola is entirely enclosed by bone, but in S. verdeluzicola the clavicular fenestra is proportionally larger, resulting in a very thin anterior margin (Fig. 8). The two species also display differences in the position of the clavicular foramen, with S. verdeluzicola displaying a foramen near the anterior edge (Fig. 8H) and S. klauberi in the middle of the clavicle (Fig. 8G). (Diaz-Lameiro et al. 2022)
Description of holotype. Body short and stocky; 23.3 mm SVL, postpygal section of the tail absent (clipped for tissue sampling). Head length 7.5 mm (32% SVL), head width 4.1 mm (54.6% head length); anterorbital region triangular with a short and tapering snout, ending on a blunt tip. Scales on snout tend to have a honeycomb pattern towards the midline with low keels, and transition to more elongated scales (but still hexagonal) in the interocular region; scales transition rapidly to about twice as long and wide in the nape region, and keels become more evident. Scales in the neck area are twice as large as the ones in the nape region, there is an irregular patch of scales in the dorsum of the neck (right side) and could be an area that was regenerated as this is not visible in any other specimens. 3 internasals, 4 loreals, 3 supralabials, and 3 infralabials. Pupil rounded, ear opening evident, red iris. Rostral wide with a median cleft and dorsal fissure. Mental scale large forming the entire chin region, 3 postmental scales, first infralabials are slightly wedge shaped, postmental scales are 2 to 3 times larger than the scales in the gular region, postmentals tend to be more juxtaposed, while the ones in the gular region more imbricated. Trunk scales in the dorsum and vent are similar in size, the scales on the dorsum keeled and scales on the vent smooth. The specimen is more pigmented on the dorsum than on the vent, pigmentation in the vent limited to some dark freckles on some scales, and a few light brown scattered scales. The snout is light brown with a well-defined canthal line, supraocular region dark, and a light club-shaped frontal area, followed by a dark pentagonal patch in the parietal region. A less defined dark patch in the nape and neck. No scapular patch with ocelli. Coloration on the dorsum is darker. Approximately 46 scales around the mid-body, and 66 rhomboid, light-colored scutcheon scales (being pigmented only on the edge, forming a dark frame for each scale). Limbs short and stocky, toes free of any webbing, and bearing an apical toe pad. Relative length of digits of manus: I,II,IV,V,III, and of pes: I,II,III,V,IV; digit V of pes in opposition to I–IV. (Diaz-Lameiro et al. 2022)
Description. Sphaerodactylus verdeluzicola is small (median SVL = 21.50 mm) and does not exhibit sexual size dimorphism (Wilcoxon test, n = 24, P = 0.34; males x ̄ = 22.30 mm, females x ̄ = 21.70 mm). Measurements and scale counts for the holotype and paratypes are provided in Table 2. Body scales are similar to those of other geckos from Puerto Rico (e.g., members of the S. macrolepis complex; Daza et al., 2019), in having acute, flattened, keeled, and imbricate scales in the dorsum and limbs; rounded, flattened, keeled, and imbricated scales in the abdomen; escutcheon scales that extend into the ventral surface of the thighs, almost reaching the back of the knee (popliteal region); and subcaudal scales that are also rounded like the abdomen scales, but these are 2 or 3 times larger and unkeeled. Cephalic scales include: 1 subdivided rostral, 3 internasals, 3 supralabials, 3 infralabials, 1 mental, and 2 postmentals. The dorsal cephalic scales (Fig. 2) include juxtaposed hexagonal or rhomboid keeled canthals, which transition into juxtaposed, oval, keeled frontals and supra-orbitals. The parietals are juxtaposed, rhomboid, and keeled. The transition to neck scales is gradual, and in the neck area, the scales duplicate in size and become more imbricated and pointed. In the ventral side (Fig. 2), there is a large mental scale, followed by 2 hexagonal postmentals. Gular scales are mostly unkeeled, but the scales adjacent to the infralabials are strongly keeled and look like elongated hexagons. In the gular area, there are scattered keeled scales, and a transition from hexagonal to rounded scales occurs. Scales become markedly keeled in the neck ventral region. (Diaz-Lameiro et al. 2022)
Color and pattern. The ground color of S. verdeluzicola is typically light brown with scattered light (yellowish or greenish cream) and dark (chestnut to dark brown) markings including lines, spots, and patches. Sphaerodactylus verdeluzicola displays a dark supraocular wedge, and a characteristic light-colored cephalic figure which resembles a club shape. Sphaerodactylus verdeluzicola displays a dark pentagonal parietal patch with the point aiming towards the snout (Figs. 2, 3), with the peak of the pentagon formed by a single scale. The maximum width of the parietal patch is about one-third the overall head breadth. There are two symmetrical dark nuchal patches, bounded caudally and medially by light lines, together defining an ‘‘L’’ or ‘‘C’’ shape. The nuchal patches are not continuous with the scapular patch.
Two narrow dark lines extend from the flanks of the parietal patch towards the interorbital area in a ‘‘V’’ shape, bounding a ground color cephalic figure, and ending abruptly at the rostral margin of the eye without contacting each other. Anteriorly, the two lines become continuous with dark gray coloration around the eyes. A lighter (cream) postocular stripe is present lateral to these two dark stripes and extends from the eye to the margin of the parietal patch. The postocular stripe is about three scales thick and is bounded inferiorly by a narrow dark stripe that is one or two scales thick. A dark brown canthal line is also present.
A dark scapular patch is present with two small white ocelli. The shape of the scapular patch resembles a bowtie, with two dark lateral rhombuses connected by a middle transverse line. There is a matching dark brown stripe on the lateral side of each ocellus, about one or two scales wide and about as long as the medial line. There are two lighter lines in bone brown color, one or two scales thick, lateral to the dark lines. An additional dark line in dark brown, one to two scales thick, is also present lateral to the light lines. These light-dark lines extend just caudal to the patch along the sides of the body.
The dorsal tail is the same color as the dorsum of the body. Markings in the pygal region include a dark brown chevron with the tip of the ‘‘V’’ pointing caudally, bound by cream or white posterior margins (Fig. 2). Laterally, there is a light-colored stripe, one to two scales thick, with dark brown lines (one to two scales thick) running parallel above and below. The ventrum is light colored, and a few dark scales can be found scattered on the ventral surface (Fig. 2). The dorsal ground color extends laterally onto the sides of the ventrum. There is a lighter patch of color extending from the lower ventrum to the thighs and the escutcheon region. The light stripe and vent are light yellowish cream. The tail is light cream-colored ventrally, with more dark spotting than the ventrum proper.
Color differences between live and alcohol-preserved specimens. Dorsal color in the live animals is typically lighter and brighter than in alcohol-preserved specimens, which appear darker overall. The light ventral color may vary from cream to straw-colored in alcohol-preserved specimens. Red coloration on the tail, when present, also fades in the alcohol-preserved specimens. Nonetheless, the pattern in alcohol-preserved specimens remains clearly distinguishable. (Diaz-Lameiro et al. 2022)
Morphological variation. Using collected specimens, we determined that adult SVL ranged from 19.49 mm to 25.48 mm (x̅ = 21.29361.78 mm; n = 24). Live adults weighed between 0.20 g and 0.50 g (x̅ = 0.3160.07 g; n = 32). Three gravid females weighed between 0.35–0.50 g. Male–female differences in size are also shown in Figure 5, using only vouchered specimens. Sphaerodactylus verdeluzicola in Rinco ́n (Fig. 1) has smooth (unkeeled), slightly round pectoral scales that are juxtaposed rather than imbricated, while all specimens from Bosque Estatal de R ́ıo Abajo have slightly overlapping, rhomboid pectoral scales with faint, partial keels (Fig. 6).
Although the majority of specimens have a light brown ground color with variable spotting patterns, some specimens display a darker or more uniform brown coloration. There is no sexual dichromatism in S. verdeluzicola (Fig. 5). Juveniles generally have more distinct markings with brighter light colors and darker dark colors than the adults, but otherwise do not differ from the adults in the pattern of coloration.
Iris color varies from amber to red (Fig. 3). The dorsal head pattern can be variable (Figs. 2, 3). The dark gray coloration around the eyes is not present in all individuals, and as a result the dark stripes on the face are not always continuous with the dark eye coloration. When present, the dark eye coloration may also have some green. The pentagonal parietal patch varies in size (8 to 10 scales long). Some parietal spots are more triangular or heart-shaped than pentagonal but are always dark, with the tip pointing rostrally. Although the dark stripes lateral to the parietal patch extend caudally and laterally in some specimens, in others the two stripes never extend caudal to the parietal spot. The light stripe lateral to the parietal patch is always present but may be from one scale up to six scales wide and may vary in color. The size and density of the nuchal patches vary from a few dark scales on either side to two large patches covering most of the nuchal area, which sometimes join to form one continuous patch. Occasionally the nuchal patches are continuous with the parietal patch.
The size, shape, and color intensity of the scapular patch varies. In some specimens, the patch is more square-shaped and solidly filled with the dark brown color, but in other specimens the patch is less distinctly separated from the ground color. In some cases, it lacks the transverse connecting line altogether or displays only one or two dark lines medial to each ocellus (Figs. 2, 3). Some specimens display a medial longitudinal line at the center of the patch, and sometimes this medial line joins the lateral stripes caudal to the ocelli. The medial line ranges from one or two scales longitudinally to an extended stripe up to 12 scales long. Ocelli in the scapular patch typically comprise one scale but can be as large as three or four scales forming a triangle or diamond pattern, and they range in color from white to tan. The light dorsolateral lines extend significantly beyond the caudal border of the scapular patch, but they are sometimes surrounded by an additional dark stripe.
Markings on the dorsum of the tail are variable, but in addition to the typical dark-light chevrons there are sometimes additional spots or blotches present on the tail, following the same dark-light pattern. The lateral stripes on the tail are always present but vary in length. Ventrally, some males can also have stippled oblique lateromedial lines on the throat. A dark stripe is sometimes present anterior to the vent and some individuals have an abrupt change in coloration at the escutcheon area. Some individuals display yellow to red coloration on the ventral side of the tail. The number of lamellae in the foot IV toe differs between populations of S. verdeluzicola. The specimens of S. verdeluzicola from Rincón fluctuate between 6 and 9 (median = 8, n = 8) lamellae, while in the Bosque Estatal de R ́ıo Abajo population the number ranges between 9 and 12 (median = 10, n = 17) lamellae. The Bosque Estatal de R ́ıo Abajo population overlaps in this trait with populations of S. klauberi from El Yunque, which have between 11 and 13 (median = 12, n = 7) lamellae. (Diaz-Lameiro et al. 2022)