Marisora unimarginata (Cope)

Mccranie, James R., Matthews, Amy J. & Hedges, S. Blair, 2020, A morphological and molecular revision of lizards of the genus Marisora Hedges & Conn (Squamata: Mabuyidae) from Central America and Mexico, with descriptions of four new species, Zootaxa 4763 (3), pp. 301-353 : 338-339

Marisora unimarginata (Cope)

Southern Middle America Skink

Fig. 14A, B, C, D

Mabuia unimarginata Cope 1862:187 (no holotype designated; type locality: “ Panama ”).

Marisora unimarginata : Hedges & Conn 2012:119.

Mabuya unimarginata complex: Pinto-Sánchez et al. 2015:195 (in part).

Diagnosis. Marisora unimarginata is a long-limbed, relatively large species of Marisora characterized (data for four males and eight females examined for this work or data from Hedges & Conn 2012 [those marked by an * in Appendix 1], plus data from Taylor 1956 where noted) by (1) maximum known SVL in males 84.0 mm; (2) maximum known SVL in females 90.3 mm; (3) SW 2.7–3.9% SVL in males, 2.2–4.9% in females; (4) HL 19.5–25.0% SVL in males, 17.3–23.6% in females; (5) HW 12.1–16.9% SVL in males, 11.3–16.0% in females; (6) EAL 1.5–2.0% SVL in males, 1.1–1.7% in females; (7) Toe IV length 10.9–11.9% SVL in males, 9.0–13.6% in females; (8) prefrontals one per side; (9) supraoculars four per side; (10) supraciliaries four per side; (11) frontoparietals one per side; (12) normally sixth (81.9%) supralabial below orbit, rarely fifth below orbit on one or both sides (18.1%; includes our data and that from Taylor); (13) nuchal rows one per side; (14) dorsals 51–56 (54.8 ± 1.2) in males, 53–60 (55.8 ± 1.4) in females (includes our data and that from Taylor); (15) ventrals 60–65 (63.0 ± 2.3) in males, 59–66 (62.9 ± 5.8) in females; (16) dorsals + ventrals 112–125 (118.8 ±5.0) in males, 112–131 (120.6 ± 5.8) in females; (17) scales around midbody usually 30 (77.1%), occasionally 32 (11.4%), rarely 29 or 31 (includes our data and that from Taylor); (18) Finger IV lamellae 13–14 (13.4 ± 0.5) per side in males, 11–15 (13.0 ± 1.9) in 11 females; (19) Toe IV lamellae per side 14–18 (16.4 ± 1.7) in males, 15–17 (16.0 ± 1.8) in 11 females; (20) Finger IV + Toe IV lamellae 28–32 (30.2 ± 1.6) per side in males, 26–32 (29.0 ± 2.4) in 11 females; (21) supranasals in medial contact, preventing frontonasal-rostral contact; (22) prefrontals not in contact medially; (23) supraocular 1-frontal contact absent; (24) parietals in contact posterior to interparietal; (25) pale middorsal stripe absent, but numerous dark brown spots present dorsally; (26) thin, indistinct dark brown dorsolateral stripe usually absent; pale dorsolateral stripe absent or indistinct; (27) dark brown lateral stripe present, about 2 1/2–3 scale rows high; (28) distinct white lateral stripe present; (29) palms and soles dark brown; (30) total lamellae for five fingers 51–54 (52.7 ± 1.5) in males, 44–54 (50.5 ± 4.5) in females; (31) total lamellae for five toes 55–62 (58.3 ± 3.5) in males, 53–60 (57.0 ± 2.9) in females. In addition, this species has a combined FLL + HLL/SVL 56.9–66.9% in males, 55.9–69.1% in females (includes data from Taylor), and usually only 1 chinshield contacting infralabials (82.9%) ( Table 3 ).

Marisora unimarginata is a member of the M. unimarginata Group of Middle American Marisora . All other Middle American species of the genus with genetic data available are members of the M. alliacea group ( Fig. 3 ). Marisora unimarginata differs from M. magnacornae in usually having the sixth supralabial below the orbit (81.9% versus fifth supralabial below orbit in 85.5% of M. magnacornae ), usually only one chinshield contacting an infralabial in 82.9% (versus 2 chinshields per side in contact with infralabials in 87.3% of M. magnacornae ), and having numerous dark brown to black spots on the body (versus only scattered and slightly darker brown dorsal scales in M. magnacornae ). Marisora unimarginata differs from M. alliacea in having the frontonasal separated from the rostral (versus frontonasal contacting rostral in 83.0% in M. alliacea ), usually only first chinshield per side contacting infralabials (82.9%; versus 2 chinshields in 84.7% in M. alliacea ), in having the dark lateral stripe 2 1/2 to 3 scale rows high (versus dark lateral stripe 3–4 scale rows high, at least in shoulder region, in M. alliacea ), and in having dark brown to black dorsal spots (versus dorsal dark brown to black lines or dashes suggestive of lines in M. alliacea ). Marisora unimarginata differs from M. brachypoda by having longer limbs (FLL + HLL/SVL of 56.9–66.9% in males and 55.9–69.1% in females versus 51.5–57.7% in males and 47.6–53.9% in females of M. brachypoda ), having dark brown palms and soles (versus pale brown to cream palms and soles in M. brachypoda ), and in having distinct dorsal dark spots (versus dorsal spots, if present small and indistinct in M. brachypoda ). Marisora unimarginata is diagnosed from the four species of Marisora described herein ( M. lineola , M. aquilonaria , M. syntoma , and M. urtica ) in the respective diagnosis of those species above. Marisora unimarginata differs from M. roatanae by the combination of having distinct dark spots on the dorsum (versus dark large spots absent or indistinct in M. roatanae ), having the sixth supralabial below the orbit in 81.9% (versus fifth in 80.4% in M. roatanae ), and in almost always having longer limbs with a FLL + HLL/SVL of 56.9–66.9% in males and 55.9–69.1% in females (versus 53.5–58.4% and 47.8–57.7%, respectively, in M. roatanae ). Marisora unimarginata differs from the extralimital M. pergravis by having distinct dark dorsal spots (versus those markings absent in M. pergravis ).

Distribution. Marisora unimarginata is known to occur on the Pacific versant from northwestern Costa Rica to at least eastern Panama ( Fig. 6 ). This species is also known to occur on the Caribbean versant in the Canal Zone region of central Panama. Its known elevational range is from near sea level to about 1500 m, but most localities are below 600 m. Because of the geographic restriction of this study, we do not plot the distribution of specimens in South America tentatively assigned to this species.

Remarks. Recognition of Marisora unimarginata is also supported by our genetic results ( Fig. 3 ) and morphological studies. Tissues of M. unimarginata (sensu stricto) were not available for previous genetic studies, thus are sequenced for the first time in the current study. Photographs in life of three of those four vouchers are presented herein ( Figs. 14B, C, D ).

Fitch (1985) indicated seven Costa Rican females, apparently of this species, gave birth to 2–7 (5.2) young, apparently in March and August (also see reproduction remarks for M. alliacea ). Images of Marisora unimarginata are in Leenders (2001) and Taylor (1956).

Figures

FIGURE 3A. Phylogenetic tree of the genus Marisora from a maximum-likelihood analysis of DNA sequences of three mitochondrial genes (12S rRNA, 16S rRNA, and cyt b) and three nuclear genes (NGFB, R35, and RAG2) in 140 individuals (4,029 bp). A scale bar (2% sequence divergence) is indicated below. The numbers at left of nodes are bootstrap support values. The tree is rooted with Mabuya dominicana. Species delimited using ABGD indicated by black vertical lines at right; samples with horizontal bars missing cytochrome b Figure continues on two pages.

FIGURE 6. Map showing the localities of the Marisora specimens examined for this study. The gray arrow points to island record for M. urtica. Two extralimital species are also indicated: M. berengerae (San Andres, purple arrow) and M. pergravis (Providencia, yellow arrow).

FIGURE 14. Marisora unimarginata showing dorsal pattern. (A) Adult male (FMNH 178691) (near San Isidro del General, San José, Costa Rica) in preservative, SVL 75.0 mm; (B) Live adult male (SMF 89582) from Café de Eleta, Chiriquí, Panama; (C) Live adult female (Museo Herpetológico de Chiriquí 2349) from Café de Eleta, Chiriquí, Panama; (D) Live adult (SMF 91565) from Guayabito, Veraguas, Panama. These images show the known range of variation in dorsal spotting in M. unimarginata, with the least spotted specimen also being the considerably least common phase. Images B, C, and D by Sebastian Lotzkat.