Bachia, Thomas, 1965

Murphy, John C., Salvi, Daniele, Santos, Joana L., Braswell, Alvin L., Charles, Stevland P., Borzée, Amaél & Jowers, Michael J., 2019, The reduced limbed lizards of the genus Bachia (Reptilia, Squamata, Gymnophthalmidae); biogeography, cryptic diversity, and morphological convergence in the eastern Caribbean, Organisms Diversity & Evolution (New York, N. Y.) 19 (2), pp. 321-340 : 333-337

Hex-scaled Bachia from the Caribbean coastal range of Venezuela

Five specimens collected at Caripito, Venezuela, were examined by Dixon (1973) and identified as Bachia heteropa heteropa × Bachia h. trinitatis . The presence of three toes on the feet, the lack of prefrontals, and the second pair of chin shields in medial contact suggest to us that these represent an undescribed species, and we describe it below.

Bachia beebei sp. nov.

Fig. 8

Bachia heteropa heteropa × Bachia heteropa trinitatis ― Dixon 1973:33.

Holotype An adult male, AMNH 137630 from Caripito Venezuela (10°7′N, 63°6′W).

Diagnosis A Bachia with (1) no prefrontal scales; (2) the first supraocular is the longest, and extends over the loreal; (3) the frontonasal is hexagonal; (4) four digits are present on the manus and three on the pes (phalange formulas: manus 1–2– 2–1–0, pes 1–2–2–0–0); (5) a band of 12 rows of imbricate hexagonal scales on the dorsum; (6) scales around mid-body 26–28; (7) 39–40 transverse rows of dorsals; (8) the fifth upper labial contacts last supraocular; (9) the gulars are in six or seven; (10) the second pair of chin shield are in medial contact; (11) an interparietal present.

Variation Two males were 40 and 55 mm in SVL ; one female was 40 mm SVL . The tails were all damaged. Beebe (1945) describes one individual that had a total length of 165 mm before breaking its tail. Forelegs were 0.08–0.99 of the SVL and legs were 0.08–0.10 of the SVL. Head widths were 0.09– 0.11 of the SVL, head lengths were 0.14–0.15 of the SVL of the SVL. Supraciliaries range from 2 to 4 (usually three), one specimen has two on both sides, another has three on one side and four on the other; two other specimens have three on both sides. The number of lower labials can be five or six; gular rows are seven, one specimen has six. Scale rows around mid-body are 29, one specimen has 28 (X = 28.80, SD = 0.40); dorsal scale rows are 39–40 (X = 39.4, SD =0.49). Transverse ventral scale rows are 27 or 28 (X = 27.20, SD = 0.40).

Description of the holotype A male, SVL 55 mm, front leg 4.6 mm, rear leg 4.6 mm, head length 8.2 mm, head width 5.5 mm, head depth 4.5 mm. Body elongate, a sulcus between the head and nuchal region, snout rounded, tail broken. Rostral small, barely visible from above, contacting first supralabial (same as the lower lobe of the nasal scale), nasal, and frontonasal. Viewed from above, the rostral is about twice as wide as high; in lateral view, it projects slightly over the anterior margin of the jaw. Prefrontals are absent. Frontonasal hexagonal, broader than long, with anterior margin flat, lateral margins straight and expand laterally, in contact with loreal and first supraocular, and the first two upper labials. Frontal is octagonal, longer than wide, and in contact with the frontonasal, the first two supraoculars, the parietals, and interparietal. Parietals large, longer than wide, slightly longer and slightly wider than frontal, roughly pentagonal. Interparietal narrow anteriorly widens posteriorly. Posterior borders of parietals and interparietal coincide with the cervical sulcus in the occipital region. Four supraoculars, the first is the longest, the third the smallest. Two superciliaries are present. Nasal large, longer than tall and complete; nare in the anterior middle of the nasal, fused to first upper labial. Loreal pentagonal, undivided and in contact with upper labials 2–3, preocular, frontal, internasal, and supranasal. Six upper labials (counting the lower portion of the nasal as the first upper labial); the first is below the nare and forms the bottom half of the nasal; 3–5 contacting suboculars, the fifth is the tallest, the fourth is the shortest, the sixth longest. Scales around the orbit are one subocular; one preocular, one postocular. Eyelid present with an undivided semitransparent scale. Ear-opening is absent. All head scales smooth and juxtaposed. Mental broader than long, slightly broader than the ventral surface of rostral. Postmental roughly hexagonal; longer than wide. Two pairs of chin shields, both pairs are in medial contact; the anterior pair is smaller; followed by a row of five pre-gulars, the medial pre-gulars are divided into smaller scales at the sulcus. Six lower labials, first two pairs contact the post mental. Gulars smooth, imbricate, rounded posteriorly, in seven transversal rows; gular scales gradually increase in size toward the pectoral region. The pectoral region has two central plates, each longer than wide, and a pair of two smaller scales laterally (scale on left divided), pectoral formula 2112. Lateral scales of neck rectangular, smooth, imbricate, and slightly rounded posteriorly, wider than long. Gular fold present. Dorsal scales are imbricate and in 39 transverse rows between interparietal sulcus and the level of hind limbs. Lateral scales about the same size as the dorsals; those closer to ventrals slightly wider. Granular scales at the insertion point of limbs. Scales around mid-body 28, 12 rows of these on the dorsum are hexagonal. Ventral scales smooth, longitudinally imbricate, laterally juxtaposed, almost square, those after mid-body narrower; 27 transverse rows between interbrachials and preanals. Four preanal pores present. Cloacal shield composed of four scales, lateral scales small. The front limbs have four clawed digits on each hand the rear legs have three digits on each foot. The front limbs are equal to five rows of transverse lateral scales, and the hind limbs are equal to about seven rows of transverse lateral scales.

We have not observed this lizard alive. However, Beebe (1945) described the coloration in life as B Chestnut brown above with a wide band down the back of dull cinnamon gray stippled with chestnut, fading into solid chestnut toward the tail. A tan row stripe of chestnut down the center of the dorsal band. The band is edged on each side with a linear series of arrowheads of pale olive buff. Inner border of these marks edged with chestnut. The arrowheads get smaller and fade out entirely toward the tail. Iris straw yellow.^

Similar species Bachia alleni and B. trinitatis have four digits on each pes and prefrontal scales ( B. beebei sp. nov. has three digits on each pes and no prefrontal scales). Bachia heteropa has 45–47 transverse scale rows (39–40 in B. beebei sp. nov.). Bachia whitei sp. nov. has quadrangular scales on the dorsum and no interparietal scale ( B. beebei sp. nov. has hexagonal scales on the dorsum and an interparietal scale is present). To distinguish B. beebei sp. nov. from other former members of the B. heteropa group, see Table 2.

Etymology Bachia beebei sp. nov. is named in honor of William Beebe, the premier American naturalist of the early twentieth century. Beebe made many contributions to the ecology of tropical forests as well as early deep ocean exploration. His contributions to the herpetology of the Caribbean Coastal Ranges as well as Trinidad and Tobago are often overlooked because of his more publicized contributions to natural history.

Distribution Bachia beebei sp. nov. is known only from the type locality, Caripito, Venezuela.

Ecology The environment at the type locality was described by Beebe (1943). He found the area to be highly seasonal with an extended dry period. Two species of Bachia were present at Caripito, B. cophais and B. [formerly heteropa ] beebei sp. nov. The lizards were found while digging pits, or after they had fallen into the pits; but he also extracted them from decomposing logs. He commented on their readiness to autotomize their tail and their similarity in their appearance (coloration and fine longitudinal stripes) to the snake Atractus trilineatus . This snake is also sympatric with Bachia trinitatis on Trinidad and Tobago.

Material examined AMNH 137630–34. Venezuela, Caripito.

Bachia heteropa (Lichtenstein and von Martens) .

Chalcides heteropus Lichtenstein and von Martens 1856:17 . Holotype is in the Forschungsinstut und Natur- Museum Senckenberg, Frankfurt-am-Main ( SMF 39900 ) from La Guaira, Venezuela (10° 35′N, 66° 55′W).

Bachia heteropus – Garman, 1892:97.

Bachia heteropa heteropa –Peters and Donoso Barros 1970:80.

Diagnosis A Bachia with (1) no prefrontal scales; (2) the third supraocular is the longest; (3) the frontonasal is hexagonal; (4) four digits are present on the manus and three on the pes (5) a band of imbricate hexagonal scales on the dorsum; (6) scales around mid-body 28–30; (7) 4–47 transverse rows of dorsals; (8) the fifth upper labial contacts primary temporal; (9) the gulars are in six or seven; (10) the second pair of chin shield are in medial contact; (11) a sub-triangular interparietal present.

Material examined Venezuela (1) UMMZ 55880.

Bachia lineata (Boulenger) .

Bachia lineata Boulenger 1903:432 . Type-locality, Duaca , Venezuela. (10° 16′N, 69° 08′W) (Holotype, British Museum Holotype, British Museum of Natural History (NHM) 1946.8.2.41 (formerly 1902.7.29.90), an adult, collected by Mr. Wayman (purchased from Mr. Rosenberg), date of collection unknown, but registered into the collection on 29 July 1902.

Bachia anomala Roux 1929:31 . Type-locality, El Mene, Distrtict Acosta, Falcon Province, Venezuela (11° 02′N, 68° 29′W). Holotype, Naturhistorisches Museum, Basel (NMBA) 9912, an adult male (SVL 52 mm), collected by H.G. Kugler and presented to the museum in 1929. Shreve (1947) suggested that B. lineata and B. anomala might not be conspecific. He noted that Boulenger’ s description stated the dorsal scales were quadrangular and suggests this led Roux into thinking his specimen was new. Burt and Burt (1931) placed B. lineata in the B. cophias group. Boulenger’ s description also reports five longitudinal dorsal stripes, with Shreve noting that none of the specimens he examined had more than three.

Bachia heteropa lineata : Mijares-Urrutia and Arends 1999:115.

Diagnosis A Bachia with (1) no prefrontal scales; (2) the third supraocular is the longest; (3) the frontonasal is hexagonal; (4) four digits are present on the manus and three on the pes (5) a band of imbricate hexagonal scales on the dorsum; (6) scales around mid-body 24–26; (7) 42–45 transverse rows of dorsals; (8) the fifth upper labial contacts primary temporal; (9) the gulars are in six or seven; (10) the second pair of chin shield are in medial contact; (11) a sub-triangular interparietal present.

Material examined Data from the literature.

Bachia marcelae Donoso-Barros and Garrido.

Bachia marcelae Donoso-Barros and Garrido 1964:1 . Type-locality, La Luz , Edo. Barinas, Venezuela (8° 23′ N, 69° 49′ W). Holotype, Museo de Zoologia de la Universidad de Concepción, Chile (MZUC) 8578, male holotype (D-B 6312061 in the original publication). Collected on 12 December 1963 by R. Donoso-Barros and A. Garrido.

Bachia lineata marcelae – Donoso-Barros 1968:117.

Bachia heteropa marcelae – Dixon 1973:33.

Diagnosis A Bachia with (1) no prefrontal scales; (2) two supraoculars; (3) the frontonasal is hexagonal; (4) four digits are present on the manus and two on the pes (5) a band of imbricate hexagonal scales on the dorsum; (6) scales around mid-body 25; (7) 39–42 transverse rows of dorsals; (8) the fifth upper labial contacts primary temporal; (9) the gulars are in five rows; (10) the second pair of chin shield are in medial contact; (11) a sub-rectangular interparietal present.

Material examined Data from the literature.

The Quad-scaled Bachia from Tobago.

Three specimens collected in the late 1970s have been previously considered to be related to Bachia flavescens . This taxon is a previously undescribed species, distinct from the Guyana specimens of flavescens -like Bachia that we examined. A fourth specimen was collected on Tobago in 2017. We believe this species is a Tobago endemic.

Bachia whitei sp. nov.

Fig. 7c, d .

Bachia cf. flavescens – Hardy 1982:78.

Bachia flavescens – Murphy 1997:133.

Holotype USNM 227942 , a male from Hillsborough Dam , Tobago (11°13′ 32″N, 60°40′ 10″W). Collected 21 December 1978 by Alvin L. Braswell.

Referred material USNM 227944, 227943, UWIZM 2017.15.6.

Diagnosis A Bachia with (1) no prefrontal scales; (2) the second supraocular is slightly longer than the first; (3) the frontonasal is hexagonal; (4) three clawed digits on each manus and two digits on each pes; (5) there are quadrangular scales on the dorsum; (6) scales around mid-body 31–32; (7) transverse dorsals in 47–49 rows; (8) the fifth upper labial does not contact the last supraocular; (9) there are eight rows of gulars; (10) the second pair of chinshields are widely separated; (11) an interparietal scale is absent.

Measurements SVL– 58.5 mm, head width 3.98 mm, head length 6.75 mm, head depth 3.02 mm.

Description of the holotype Body elongate, with a sulcus between the head and nuchal region, snout rounded, tail broken. Rostral small, barely visible from above, contacting the first supralabial, nasal and frontonasal scales; viewed from above the rostral is about twice as wide as high; in lateral view, it projects slightly over the anterior margin of the jaw. Prefrontals are absent; frontonasal heptagonal, longer than wide, with anterior margin pointed, lateral margins straight to slightly concave, in contact with loreal and three superciliaries. Parietals large, longer than wide, slightly longer and slightly narrower than frontal, roughly pentagonal; posterior borders of parietals and dorsals coincide with the cervical sulcus in the occipital region. Three supraoculars, the second is the largest three superciliaries. Nasal large, longer than high and completely divided; nostril in the anterior lower margin of the nasal, invading the upper border of the first supralabial. Loreal square, undivided and in contact with upper labials 2– 3, the preocular, the frontal, the internasal and the supranasal. Six upper labials; first is below the nare and forms the bottom half of the nasal; 3–5 contact the oculars, the second is the tallest, fourth is smallest, sixth is longest. Scales around the orbit are: one subocular; one preocular, a postocular absent. Eyelid present with an undivided semitransparent scale. Ear-opening is absent. All head scales smooth and juxtaposed. Mental wider than long, slightly broader than the ventral surface of rostral. Postmental roughly heptagonal; longer than wide. Two pairs of chin shields, contacting lower labials 2– 3; the anterior pair smaller, in broad contact at the midline; second pair separated by a pair of smaller scales, followed by a row of pre-gulars, inner scales are the largest. Five lower labials, first pair contact first and second lower labials. Gulars are smooth, imbricate, rounded posteriorly, in eight transversal rows; gular scale rows are increasing gradually in size toward the pectoral region. The pectoral region with two central scales, longer than wide, a pair of two smaller scales laterally (scale on left divided). Lateral scales of neck rectangular, smooth, imbricate, and slightly rounded posteriorly, longer than wide, in regular transverse rows and becoming gradually similar to adjacent dorsal and ventral scales. Gular fold present. Dorsal scales are imbricate and in 47 transverse rows between interparietal sulcus and the level of hind limbs. Lateral scales are about the same size as the dorsals but smooth; those closer to the ventrals slightly wider. A distinctive area with granular scales present around insertion of limbs. Scales around mid-body are 32. Ventral scales smooth, longitudinally imbricate, laterally juxtaposed, almost square just after the interbrachial row, becoming gradually longer than wide, rounded posteriorly, those after mid-body narrower; 38 transverse rows between interbrachials and preanals. Four preanal pores are present. Cloacal shield composed of five scales, with small lateral scales. The front limbs have three clawed digits on each hand the rear legs have two digits on each foot.

Color in alcohol based on a fresh specimen. Head is a uniform brown; the lower surface is cream to tan. The dorsum is brown; ventral surface is cream to beige. Some dark flecking on the anterior gulars. Two dorsolateral stipes edge the sides of the hexagonal band. There is a dark gray-brown indistinct mid-dorsal stripe. Lateral body and limbs are slightly darker than the dorsum. The tail’ s dorsum has three dark stripes on the base of the tail, and they fade posteriorly, the ventral surface of the tail becomes darker distally.

Similar species This species can be readily distinguished from all other Bachia in the eastern Caribbean by the absence of hexagonal scales (it has only quadrangular shaped scales on the dorsum), three digits on the hands, two digits on the feet, it has 31–32 scale rows around the body and 47–49 transverse rows of dorsals from the occiput to just behind the back legs. Bachia alleni and B. trinitatis all have a band of hexagonal scales on the dorsum that is usually seven to 12 scales wide, they have four or five digits on the manus, and four digits on the pes. All of the specimens of the B. flavescens group we examined lacked the band of hexagonal scales, some have three fingers and one toe, others have three fingers and two toes, but all have seven rows of gular scales (instead of eight), two supraoculars (instead of three), and four or five upper labials instead of six. This species also has a uniquely shaped cloacal plate composed of three plate-like scales. All other species examined have a cloacal plate consisting of four plate-like scales. Parietal scales are not separated by an interparietal as they are with B. trinitatis .

Because B. flavescens is a composite species, it is impossible to provide a comparison of B. whitei sp. nov. to B. flavescens . We did compare B. whitei sp. nov. to two candidate species (species A and B) of the B. cf. flavescens group from Guyana. Bachia whitei sp. nov. has a more slender-body, a lighter base color in the preserved state, and their heads tend to be narrower (HW/HL x = 0.5986, n = 2). Guyana B. cf. flavescens sp. A have a more robust body, they are darker in color in the preserved state, and their heads tend to be slightly wider (HW/HL x = 0.6182, n = 2). They have 26 scales rows at mid-body, 35–37 scale rows between the pectoral and anal plates, seven gular scale rows, a pentagonal lower posterior temporal, two supraoculars, four upper labials, and distinctive chin scale morphology. Guyana B. cf. flavescens sp. B has a robust body, darker base color with characteristic longitudinal striping pattern in the preserved state, and the head is quite broad (HW/HL = 0.6849, n = 1). The specimen has 32 scale rows at mid-body, 38 scale rows between the pectoral and cloacal plates, seven gular scale rows, a quadrangular lower posterior temporal, two supraoculars, five upper labials, and chin scale morphology that closely resembles that of Guyana Bachia sp. A .

Etymology Named in honor of Graham White, for his contributions to the natural history and conservation of the Trinidad and Tobago fauna. He has extensive knowledge of the biodiversity of Trinidad and Tobago, is an avid birder and a member of the Trinidad and Tobago Rarities Committee since its inception in 1996. He is a long-standing member of the Trinidad and Tobago Field Naturalists’ Club (TTFNC) and has served on the Editorial Committee of the Living World Journal published by the TTFNC from 1999 to 2014 and as the Editor 2015-present. Mr. White is also the Chairman of the Asa Wright Nature Centre.

Distribution Of the four known specimens, reliable locality data is available only for the type specimen (Hillsborough Dam) and UWIZM.2017.15.6 which was found on Spring Trail, in the Main Ridge Forest Reserve of Tobago (11°16′ N 60°35′W). Both locations are on the Tobago’ s Main Ridge and are about 10.5 km apart.

Natural history The first specimen of B. whitei sp. nov. collected came from a pile of cut grass/lawn debris that it shared with Bachia trinitatis . The debris pile was about 50 m from the forest edge. The other two specimens collected in the late 1970s came from unknown localities. The most recent specimen collected was along a Main Ridge Trail and was under a piece of palm that was laying on wet, bare soil in the closed canopy forest. The female specimen behaved much differently than B. trinitatis when we photographed it. Bachia trinitatis tried to hide under leaves and debris, while B. whitei sp. nov. used its tail to propel its body into the air in attempts to escape.

Material examined Bachia whitei sp. nov. (n = 4) TOBAGO USNM 227942– 44, UWIMZ 2017.15.6. Bachia cf. f l a v e s c e n s (n = 1 8): B R A Z I L – A M N H 6 4 8 6 9 – 7 1;

COLOMBIA – USNM 65437; GUIANA – AMNH 25086, 29084, 140924, 151917, 151922, 151924, 151931–32; FMNH 23801, MCZ 1688, UMMZ 65170, USNM 566424, 566426. No data: AMNH 3580.

Figures

Fig. 8 Bachia beebei sp. nov. AMNH 137630. a Crown view note absence of prefrontals. b Profile. c Gular view. D. Manus, with three digits. e Pes with four digits. Each bar is about 1 mm

Fig. 7 a, b Bachia trinitatis from Flagstaff Hill, Tobago (JCM). c, d Bachia whitei sp. nov. UWIZM.2017.15.6. A female from Main Ridge Reserve, Tobago (JCM)