Marisora lineola, Mccranie & Matthews & Hedges, 2020

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 : 312-317

Marisora lineola sp. nov.

Mayan Skink

Figs. 5A, B, C, D

Mabuia agilis: Günther 1885:33 (in part); Boulenger 1887:190 (in part).

Mabuya agilis : Ruthven 1912:323; Stuart 1934:13; Stuart 1935:47; Gaige 1936:298; Burt & Myers 1942:49 (in part).

Mabuya mabouya : Dunn 1936:539 (in part).

Mabuya mabouya mabouya : Dunn 1936:544 (in part); Gaige et al. 1937:11 (in part); Smith 1938:5; Schmidt 1941:496; Smith 1942:344; Stuart 1948:55; Smith & Taylor 1950:156 (in part); Maslin 1963:15.

Mabuya mabouya alliacea : Burger 1952:186 (in part); Werler & Smith 1952:563; Stuart 1954:57; Stuart 1958:23.

Mabuya brachypoda : Webb 1958:1311 (in part); Neill & Allen 1959:45; Smith 1960:223; McCoy & van Horn 1962:182; Neill

& Allen 1962:85; Duellman 1965a:603; Neill 1965:98; McCoy 1966:307; Greer 1970:172; Villafuerte & Florés-Villela

1992:47; Campbell 1998:Fig. 104 legend only. Mabuya unimarginata : Lee 1996:247; Calderón-Mandujano & Mora-Tembre 2004:295; Luja 2006:469. Mabuya unimarginata complex: Miralles et al. 2009a:68 (in part; molecular data only); Pinto-Sánchez et al. 2015:204 (by im-

plication only, no specimens examined). Marisora brachypoda : Hedges & Conn 2012:24 (in part); Lara-Resendiz et al. 2017:226 (in part; spot locality map).

Holotype. MVZ 88405 , an adult female from El Salto , near Laguna Encantada, Escuintla, Guatemala, 14°16’53”N, - 90°42’38”W, elevation 275 m, collected 2 March 1969, by “Woods & Crenshaw.”

Paratypes (15). GUATEMALA—MVZ 88406, adult male from the same locality as the holotype; Jutiapa: FMNH 68712, adult male, 7 miles W of Jutiapa; Petén: USNM 71382, adult female, Chuntuquí; USNM 25116, adult male, Sacluc; USNM 71951, adult female, “ Petén.” MEXICO— Campeche: KU 70560, adult male, 4 km S of Champotón; Chiapas: USNM 113656, adult male, USNM 113658–59, 113663, adult females, La Esperanza; USNM 113646, adult female, Palenque 17°32.30’N, 91°59.30’W; Tabasco: KU 41604, male, 19 miles N, 10 miles E of Macuspana; USNM 113640–41, adult female and adult male, respectively, Tenosique; Yucatán: KU 157475, 13.6 mi E of Mérida.

Referred specimens (62; all examined). BELIZE— Belize: USNM 25447, 26074, 31337, 58161–62, Belize City; Orange Walk: USNM 194103–04, Otro Benque; Stann Creek: USNM 33092, 29 km SSW of Dangriga; LSUMZ 10282, 1.5 mi W of Mango Creek; Toledo: USNM 496705–06, Big Falls 16°15.57’N, 88°52.12’W. GUA- TEMALA— Escuintla: UTA R-37546, Finca Bolivia, km 87.5 on road to Puerto Quetzal; UTA R-39643, Finca el Caobanai, Autosafari; UTA R-22113, 39642, Finca Medio Monte near Palin; Izabal: UTA R-9067, 23731, 27268– 69, vicinity of El Estor; Jalapa: UTA R-39637-41, 40579, Finca Oeste de Volcán Jumay; Petén: USNM 71392, Bocomonte; USNM 71395, Flores; Quezaltenango: UTA R-27267, km 199 on CA 2, near Coatepeque; Santa Rosa: UTA R-37545, between Cuilapa and Chiquimulilla on lower slopes of Volcán Tecuamburro; UTA R-24794, Volcán Jumaytepeque. MEXICO— Chiapas: USNM 113657, 113660–62, 113664–65, La Esperanza; USNM 113667–75, Lago Acacoyagua; USNM 113647–55, Palenque; Quintana Roo: LSUMZ 33344, 5 mi S of Playa del Carmen; Tabasco: USNM 113642–44, Tenosique; Veracruz: CM 52754, E of Lago Catemaco; USNM 113645, Paso del Macho; Yucatán: USNM 145307, Isla Pérez, Arrecife Alcarán; KU 157476, 13.6 mi E of Mérida.

Diagnosis. Marisora lineola sp. nov. is a relatively stout, large species of Marisora characterized (data from 8 males, 8 females in type series) by (1) maximum known SVL in males 80.9 mm; (2) maximum known SVL in females 86.2 mm [92.5 mm in specimen not examined by us; see Neill, 1965]; (3) SW 2.6–4.5% SVL in males, 2.2–3.7% in females; (4) HL 17.9–23.8% SVL in males, 16.0–20.5% in females; (5) HW 11.9–13.6% SVL in males, 11.2–12.8% in females; (6) EAL 1.4–2.2% SVL in males, 1.1–2.4% in females; (7) Toe IV length 10.1–12.9% SVL in males, 8.9–11.6% in females; (8) prefrontals one per side; (9) supraoculars four per side; (10) supraciliaries four per side in 93.8%, five in 6.2%; (11) frontoparietals one per side; (12) fifth supralabial below orbit in 93.8%, rarely sixth (6.2%); (13) nuchal rows one per side; (14) dorsals 54–59 (56.0 ± 1.7) in males, 57–61 (58.1 ± 1.1) in females; (15) ventrals 61–69 (63.9 ± 2.6) in males, 60–65 (62.1 ± 1.8) in females; (16) dorsals + ventrals 115–126 (119.9 ± 3.7) in males, 117–124 (120.1 ± 2.2) in females; (17) midbody scale rows 30 in 68.8%, 28 in 31.2%; (18) Finger IV lamellae 11–15 (12.4 ± 1.3) per side in males, 11–14 (11.9 ± 1.0) in females; (19) Toe IV lamellae 13–16 per side in both males and females (14.7 ± 1.2, 14.3 ± 1.3, respectively); (20) Finger IV + Toe IV lamellae 26–31 (27.0 ± 2.1) on one side in males, 24–30 (26.1 ± 1.9) in females; (21) supranasals in medial contact in 88.7%, not in medial contact in 11.3%, thus frontonasal in contact with rostral in 13.3%; (22) prefrontals not in contact; (23) supraocular 1- frontal contact absent in 93.3%, point contact made in 6.7%; (24) parietals in contact posterior to interparietal; (25) pale middorsal stripe absent, but dark brown dashes suggestive of a dark brown vertebral line present in some; also dorsal region with several similar rows of dark brown dashes to spots in many, or dark brown dashes or incomplete stripes present in others, especially on posterior third of body; (26) dark brown to black dorsolateral stripe (paired in some), some scales inside stripe with paler brown centers; those dark brown stripes or dashes present above upper edge of pale brown to cream dorsolateral stripe; (27) dark brown lateral stripe present; (28) distinct cream lateral stripe present; (29) palms and soles pale brown or cream, but dark in one (UTA R-22113); (30) total lamellae for five fingers 38–51 (43.9 ± 4.1) in males, 41–49 (45.4 ± 3.2) in females; (31) total lamellae for five toes 51–60 (54.6 ± 3.5) in males, 48–57 (51.7 ± 3.2) in females. In addition, this species is relatively short-limbed with FLL + HLL/SVL 53.7–59.3% in males, 45.1–57.8% in females, and has two or three chinshields contacting infralabials (see Table 3 for some variable characters).

Marisora lineola sp. nov. is a member of the M. alliacea group of Middle American skinks. Marisora lineola is most closely related to M. alliacea ( Fig. 3 ), but differs from that species in having shorter limbs (FLL + HLL/SVL 53.7–59.3% in males and 45.1–57.8% in females versus 62.5–74.6% in males and 58.0–67.6% in females in M. alliacea ). Marisora lineola differs from M. roatanae in having cream to pale brown palms and soles (versus distinct dark brown to nearly black soles and palms in M. roatanae ) and in having 2–3 chinshields contacting infralabials (versus one chinshield making that contact in 70.8% in M. roatanae ). Marisora lineola is most easily distinguished from M. brachypoda by having one or two dark brown or black dorsolateral body lines or dark brown dashes or spots suggesting lines (versus those dark marks absent or indistinct in M. brachypoda ). Marisora lineola also differs from M. brachypoda by having more ventrals (61–69, x = 63.9 ± 2.6 in males and 60–65, x = 62.1 ± 1.8 in females (versus 50–63, x = 57.9 ± 3.4 in males and 55–62, x = 58.7 ± 3.2 in females in M. brachypoda ). Marisora lineola is distinguished from M. aquilonaria sp. nov. and M. syntoma sp. nov. (both described below) in being a larger species (maximum known SVL 80.9 mm in males and 92.5 mm in females versus 68.6 mm and 75.2 mm, respectively, in M. aquilonaria and 68.5 mm and 75.0 mm, respectively, in M. syntoma ), having a distinct pale brown dorsolateral stripe (versus that stripe absent or occasionally indistinct in M. aquilonaria and M. syntoma ), and in having one or two dark brown or black dorsolateral body lines or dark brown dashes or spots suggesting lines (versus those dark marks absent or indistinct in M. aquilonaria and M. syntoma ). Marisora lineola is further distinguished from M. syntoma by having more ventrals in males (61–69, x = 63.9 ± 2.6 versus 56–60, x = 57.4 ± 2.3 ventrals in males of M. syntoma ). Marisora lineola is distinguished from M. urtica sp. nov. by having pale brown dorsolateral stripes and 2 chinshields contacting infralabials (versus those pale dorsolateral stripes absent and 1 chinshield contacting infralabials in M. urtica ). Marisora lineola differs from M. magnacornae in having shorter limbs (FLL + HLL/SVL 53.7–59.3% in males and 45.1–57.8% in females versus 60.8–68.7% in males and 55.8–68.0% in females in M. magnacornae ). Marisora lineola differs from the extralimital to this morphological study M. pergravis by having fewer ventrals (60–69 in both sexes combined versus 70–73 in M. pergravis ), fewer dorsals (54–61 versus 62–63 in M. pergravis ), and having a dark lateral stripe (versus that stripe absent in M. pergravis ). Marisora lineola has been previously confused with M. unimarginata of the M. unimarginata group ( Fig. 3 ), but differs from that species by having the fifth supralabial below the orbit in 93.8% (versus sixth supralabial below orbit in 81.9% in M. unimarginata ), in having 2–3 chinshields in contact with infralabials (versus 1 chinshield contacting an infralabial in 82.9% in M. unimarginata ), and having shorter limbs (FLL + HLL/SVL 53.7–59.3% in males and 45.1–57.8% in females versus 56.9–66.9% and 55.9–69.1%, respectively, in M. unimarginata ). Marisora lineola is known to differ from the extralimital and poorly known M. berengerae (incomplete morphological data available only from the literature of the unsexed holotype) of the M. unimarginata group only from genetic data.

Description of the Holotype. An adult female ( Figs. 5A, B ) in a good state of preservation, except tail broken at base and lost. The tip of the tongue is protruding from the mouth. SVL 86.2 mm; HL 16.3 mm; HW 10.3 mm; SW 3.2 mm; EAL 1.2 mm; ear opening nearly oval; Toe IV length 8.9 mm; toe lengths in descending order I<V<II<III<IV.

Head scalation. Rostral wider than high, contacting first supralabial, nasals, and supranasals. Paired supranasals separated medially by frontonasal-rostral contact, contacting upper edge of anteriormost loreal (only one in entire type series with that contact; also see comments in Variation section below). Frontonasal decagonal, wider than long, laterally in contact with anterior loreal. A pair of pentagonal prefrontals, separated medially, and in contact with frontonasal, anterior and posterior loreals, first supraciliary, frontal, first supraocular, and with point contact with second supraocular on one side. Frontal heptagonal, in contact with first plus point contact with second supraocular on one side, with frontonasal, and with paired frontoparietals. Frontoparietals also in contact with supraoculars 2–4 and with parietals and interparietal. Interparietal tetragonal and lanceolate, separated from nuchals by parietals. Parietal eye not visible externally. Parietals in contact with upper primary, secondary and tertiary temporal scales. Four supraoculars per side. Four (on one side) or five (other side) supraciliaries, second longest. Nostril in posterior part of nasal, forming part of nasal division. A small postnasal bordered by frontonasal, supranasal, anterior loreal, and first supralabial. Anterior and posterior loreals squarish with posterodorsal projection on latter. One upper preocular and one lower preocular. Seven supralabials, the fifth widest and located below the orbit. Three small postoculars, considerably smaller than temporal scales. Two primary temporals, two secondary temporals, and two tertiary temporal scales. All temporal scales imbricate, smooth, cycloid, not distinctly delineated from scales on nape and side of neck. Eight infralabials. Mental scale wider than long, posterior margin straight. Postmental and two pairs of chinshields per side in contact with infralabials. Paired chinshields separated medially by a slightly smaller, somewhat cycloid-shaped scale.

Body and limb scalation. One row of enlarged nuchal scale per side, in contact medially. Other scales on nape similar in size and shape to dorsals. Lateral neck scales slightly smaller than dorsolateral nape scales. Dorsal scales cycloid, imbricate, smooth, 57 in a longitudinal row. Axillary pit absent, but tiny scales present in that region. Ventral scales similar in size and shape to dorsals, 60 in a longitudinal row. Thirty scales around midbody. No distinct boundaries between dorsals, laterals, and ventrals. Scales on base of tail and limbs similar in shape to dorsals, but smaller on limbs. Palmar and plantar surfaces with small, slightly conical scales, subequal in size, and delineated by a surrounding region of slightly larger, flat scales. Subdigital lamellae smooth, single, 14 on Finger IV, 16 on Toe IV. Preanal scales slightly larger than ventrals. No enlarged median subcaudal scales.

Pattern and coloration in preservative. Dorsal ground color dark brown with distinct black lineate spots or dashes, those on dorsolateral portion of body more concentrated and suggesting two relatively thin dark dorsolateral stripes per side, extending from nape region to about level above hind limb insertion. Dark brown dash-like vertebral spots also suggesting a line. Pale middorsal stripe absent. Dark brown lateral stripe present, also with paler brown centers, extending from posterior edge of orbit to level above hind limb insertion. Thin (1/4 scale high) pale brown dorsolateral line bordering upper edge of dark brown lateral stripe. A single, relatively high (ca. 1 1/2 scale rows), white lateral stripe present per side, extending from rostral onto anterior portion of tail, not passing along upper edge of hind limb, passing across lower half of ear opening and with an equal height below ear opening. Lateral white stripe bordered below by a thin (1/3 scale high) dark brown line. A few indistinct dark brown spots present on medium brown dorsal surfaces of limbs. Ventral scales pale brown, with barely indicated slightly darker scale edges. Palmer and plantar surfaces cream, same color as adjacent undersides of limbs. Adjacent lamellae somewhat darker brown.

Variation. All paratypes have the supranasals in median contact, thus medial contact is the normal character state for Marisora lineola . The M. lineola paratypes are all similar in color and pattern to the holotype in preservative in having dorsal dark lines or dashes. However, some paratypes have less distinct dark lined or striped dorsal patterns. A pale brown to cream dorsolateral stripe is usually evident. Table 3 includes some of the variation recorded for measurements and proportions and scale counts for the entire type series.

Distribution. Marisora lineola is known to occur on the Caribbean versant from central Veracruz, Tabasco, and the Yucatán Peninsula, Mexico, to Guatemala and Belize ( Fig. 6 ). The species also occurs on Cozumel Island, Quintana Roo, Mexico, and on the Turneffe Islands of Belize. Marisora lineola is also known to occur on the Pacific versant at its type locality, which lies at about 275 m elevation at the edge of the coastal plain. Three Pacific coastal plain localities for this species are also known in the departments of Escuintla and Quetzaltenango, Guatemala. Another Pacific versant locality is at about 1000 m elevation in the upper reaches of a Pacific river in southeastern Chiapas, Mexico. Marisora lineola is nearly sympatric with M. brachypoda in south-central Guatemala between about 275 and 725 m elevation, with localities for the two species separated from each other by only about 15 km between that of the M. lineola type locality and that for M. brachypoda near Guanagazapa, Escuintla. The known elevational range is from near sea level to at least 1550 m.

Ecology and conservation. Lee (1996:248) wrote that this “arboreal and terrestrial skink occupies a variety of habitats within the Yucatán Peninsula including savannas, thorn forests, and tall mesic forests.” Lee also wrote that they occurred in open habitats and edge situations of those mesic forests. Skinks were found under a variety of objects on the ground and under loose bark of trees ( Lee 1996). Werler & Smith (1952) reported Marisora lineola individuals were found under loose bark of standing and fallen trees in Veracruz, Mexico. Biogeographic notes, based on his own field experiences, were reported by Stuart (1950). Álvarez del Toro (1983) wrote that Chiapan individuals, a few of which might represent this species, lived under leaves and under rotten logs on the ground, but also lived under loose bark of standing trees and inside roofs of human occupied houses. Neill & Allen (1959, 1962) noted the preference of this species for open habitats in Belize. No conservation studies have been published on any species of Marisora , but those species generally adapt well to human presence, even to the point of living inside human inhabited houses (JRM pers. observ. of all nominal forms occurring in Honduras). Thus, M. lineola is considered a species of little or no conservation concern at this time. Nonetheless, mabuyid skinks on Caribbean islands also have adapted well to disturbed habitats and coexistence with humans, yet one-third of the species became extinct following introduction of mammalian predators on the islands, in most cases within one or a few decades ( Hedges & Conn 2012). Because of their known susceptibility to inavisive predatords, the extinction risk of mabuyid skinks should be continuously monitored.

Reproduction. Webb (1958) wrote that specimens from Campeche and Yucatán, Mexico, were viviparous. McCoy (1966:307) reported five Yucatán Peninsula females had “six to nine uterine embryos each (average 7.2).” The McCoy collections were made in the last half of August. Álvarez del Toro (1983) reported, in general terms, that Chiapan females (a few might apply to Marisora lineola ) gave birth to 4–7 young from June to August. Luja (2006:469) reported a Quintana Roo female collected in April had “six totally formed young (mean SVL = 32 mm),” thus implying parturition in May. Hernández-Franyutti & Uribe (2012) studied the seasonal spermatogenic cycle in a population of this species in Tabasco, Mexico. Their recovered evidence demonstrated that spermatogenesis was the result of a single extended spermiation event.

Etymology. The specific name lineola , a noun in apposition, is Latin and means a diminutive line. The name is used in reference to the thin dorsolateral dark brown line or dorsal dark brown dashes found in this species.

Remarks. Genetic results in this study recovered Marisora lineola as a monophyletic clade ( Fig. 3 ). Thus, we consider it a species distinct from all other named Middle American Marisora populations, including those described later in this work. As noted above, M. lineola can also be defined by morphological data. Because of the poorly documented previous genetic studies, we were unable to locate a voucher specimen for those samples used in our genetic analysis. Examination of M. lineola morphological characters of specimens from nearby localities to those sequenced samples support the genetic results. Even though Pinto-Sánchez et al. (2015) recovered this population as a separate clade in their tree Cluster 1 (their ANMO1903), they did not mention those results.

Duellman (1963:246) commented on surprisingly not finding these skinks in southern Petén, Guatemala. Images of M. lineola can be found in Acevedo (2006; as M. unimarginata ), Álvarez del Toro (1983; as M. brachypoda ), Calderón-Mandujano et al. (2008; as M. brachypoda ), Campbell (1998; as M. brachypoda ; image legend only, remainder of data a composite of several species in a literature review), García-Vázquez & Feria-Ortiz (2006; second M. unimarginata ), Köhler (2003, 2008; both as M. unimarginata , but Yucatán specimen only), Lee (1996, 2000; both as M. unimarginata ), (Stafford & Meyer 2000; as M. unimarginata ), and Werler & Smith (1952; as M. mabouya alliacea ).

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 5. (A) Dorsolateral view of adult female holotype (MVZ 88405) of Marisora lineola (Escuintla, Guatemala) in preservative, SVL 86.2 mm; (B) Pale colored palms of same specimen, Toe IV length 8.9 mm; (C) Live M. lineola (SMF 99963) from along Bacalar-Reforma road, Quintana Roo, Mexico; image by Gunther Köhler; (D) Live M. lineola from El Remate, Petén, Guatemala; image by Jonathan A. Campbell.

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).