Research Article |
Corresponding author: Pier Cacciali ( pcacciali@senckenberg.de ) Academic editor: Johannes Penner
© 2017 Pier Cacciali, Nicolás Martínez, Gunther Köhler.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Cacciali P, Martínez N, Köhler G (2017) Revision of the phylogeny and chorology of the tribe Iphisini with the revalidation of Colobosaura kraepelini Werner, 1910 (Reptilia, Squamata, Gymnophthalmidae). ZooKeys 669: 89-105. https://doi.org/10.3897/zookeys.669.12245
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The family Gymnophthalmidae contains nearly 235 species with a distribution range from southern Mexico to central Argentina as well as in the Antilles. Among gymnophthalmids, the genus Colobosaura is a member of the tribe Iphisini, and currently is considered monotypic (C. modesta). The diversity of the tribe was studied recently, with the erection of several new genera. In this work genetic and morphological data of specimens of Colobosaura recently collected in Paraguay were analyzed. Genetic (16S barcode) data indicate that these samples are not conspecific with C. modesta and they are allocated to the nominal species C. kraepelini. Because the original primary type of the latter taxon is considered to be lost, a neotype (
16S barcodes, Humid Chaco, neotype, Paraguay, taxonomy
Gymnophthalmids are among the least known Neotropical lizards given their secretive habits and small size, and some of them are known only from the original description (
In the last decade, this family has been analyzed from a molecular perspective, leading to some changes in phylogenetic hypotheses (
One of the genera that underwent taxonomic modifications is Colobosaura, which was established by
In this work, and in the framework of a DNA barcoding project of the Paraguayan herpetofauna, genetic and morphology data of recently collected specimens of Colobosaura tentatively assigned to C. kraepelini were analyzed, providing a redescription of its external morphology and information on its taxonomic status.
Tissue samples for genetic analyses were extracted and stored as recommended by
The mtDNA 16S sample was compared with sequences available in GenBank for species of the most closely related clade (Iphisini: Gymnophthalminae, according to
Sequences were aligned with Clustal W (
Additionally, the external morphology of specimens of Colobosaura was examined (Appendix
A distribution map was generated for the species of the tribe Iphisini to compare ecoregional affinities of the two species of Colobosaura and its closest relatives. Ecoregional information is based on
Acronyms of institutions used in the text are
The best substitution model was GTR+G, and the phylogeny recovered is shown in Figure
Maximum Likelihood tree obtained from 16S mtDNA for the tribe Iphisini (Gymnophthalmidae). Numbers on the nodes represent the bootstrap values and numbers below branches (and scale bar at the bottom left corner) denote branch length (substitutions/site). Specimen highlighted in red indicates our sample. See Appendix
The pairwise distance shows a divergence of ~7.7% between C. modesta and
Pairwise genetic distances (lower-left diagonal), and SD (upper-right diagonal) among species of Iphisini: Gymnophthalminae.
A. mentalis | A. camacan | ( |
C. modesta | I. elegans | S. ridleyi | |
Acratosaura mentalis | 0.016 | 0.016 | 0.013 | 0.015 | 0.001 | |
Alexandresaurus camacan | 0.122 | 0.015 | 0.015 | 0.013 | 0.011 | |
Colobosaura ( |
0.122 | 0.101 | 0.013 | 0.012 | 0.011 | |
Colobosaura modesta | 0.079 | 0.103 | 0.077 | 0.013 | 0.010 | |
Iphisa elegans | 0.103 | 0.089 | 0.071 | 0.087 | 0.011 | |
Stenolepis ridleyi | 0.031 | 0.055 | 0.055 | 0.047 | 0.060 |
From the distribution it is possible to identify two groups within the tribe Iphisini: one strongly related to Amazonian ecoregions (Iphisa and Rondonops), and another linked to the Dry Diagonal (Acratosaura, Alexandresaurus, Colobosaura, and Stenolepis). Two monotypic genera (Alexandresaurus and Stenolepis) and Acratosaura spinosa are mainly associated to Caatinga environments, whereas Acratosaura mentalis have some records in Cerrado. Colobosaura modesta together with Iphisa elegans has the widest distribution, and it is strongly linked to Caatinga and Cerrado. The collecting site of
Central and northern region of South America showing the distribution (ranges in color) of the members of the tribe Iphisini. LT indicate type localities. Note that type locality for I. elegans is not shown since is referred as the whole Brazilian State of Pará. Range for A. spinosa is not shown because records come from vicinities of type locality. Colobosaura kraepelini is known only from two areas: the locality mentioned in the original description (black dot) and the neotype locality (black star); the second specimen of C. kraepelini reported here is from near the neotype locality. Orange square represents locality of the genetic sample of C. modesta (Niquelândia, GO, Brazil). Data for ecoregions according to
The genetic data presented above demonstrate that our sample
Colobosaura
kraepelini
Werner, 1910: 32 (neotype,
Colobosaura kraepelini differs from the other species of the family Gymnophthalmidae except for C. modesta, by a combination of the following characters: limbs short but well developed; Finger I vestigial, not clawed; dorsal and lateral body scales keeled; four longitudinal series of ventral scales; prefrontal present; occipital present; two pairs of chin shields. Colobosaura kraepelini differs from C. modesta by having two mid-central rows of immaculate scales (vs. four immaculate ventral rows in C. modesta); flanks completely dark (Fig.
Description of the neotype. Subadult male. Body elongated; neck not well differentiated; SVL 29 mm; tail (clipped) stump 14 mm; HL 6.55 mm; HW 4.52 mm; ED 1.42 mm; EO (oblique) 0.66 mm. Head with juxtaposed scales, except posterior edge of interparietal and parietals imbricate with occipital and first row of nuchal scales.
Rostral broad, wider (1.81 mm) than high (0.72 mm), contacting frontonasal, nasals, and first supralabials; frontonasal heptagonal, wider (1.81 mm) than long (1.30 mm), contacting rostral, nasals, loreals, and prefrontals; prefrontals wider (1.07 mm) than long (0.70 mm) with a 0.29 mm contact line between them, and contacting frontonasal, loreals, first and second supraocular, and frontal; frontal hexagonal, longer (1.67 mm) than wide (1.11), contacting prefrontals, second supraocular, and frontoparietals; frontoparietals regular pentagonal, with a 0.67 mm mid contact line between them, and contacting frontal, second (slightly) and third (broad contact) supraoculars, parietals, and interparietal; interparietal longer (2.15 mm) than wide (1.18 mm), contacting frontoparietals, parietals, first row of nuchals, and occipital; parietals broad, wider than interparietal, contacting the interparietal, frontoparietals, third supraocular, three rows of temporals, and the first row of nuchals; occipital pentagonal and small (0.57×0.83 mm) located between the interparietal and the first and second row of nuchals; nasal elongated (0.95×0.72 mm), with nares located in the mid-lower region, contacting the rostral, frontonasal, loreals, and first supralabial; loreal curved, higher (0.67 mm) than wide (0.41 mm), in contact with nasal, frontonasal, first supraocular, first superciliary, preocular (narrowly), frenocular, and first (slightly) and second superciliaries; of which the middle one is the shortest; three supraoculars, the first smaller than the other two; three elongated superciliars, being the middle scale shorter than the first and third; eleven upper palpebrals and ten lower palpebrals surrounding the orbit; semitransparent eyelid; four elongated suboculars, second and third longer than first and fourth; seven supralabials, first contacting rostral, nasal, and loreal narrowly; second contacting loreal, frenocular, and the first subocular; third and fourth supralabials in contact with suboculars; fifth supralabial (largest) contacting third and fourth subocular, lower postocular, and lower first temporal, sixth contacting the lowermost scale of the second temporal row, and other scales in the temporal region, and seventh supralabial reaching the border of the ear opening; two postoculars, the upper (in contact with the two last upper palpebrals, third superciliary, third supraocular, and upper temporal) slightly larger than the lower (in contact with the last upper palpebral, fourth subocular, fifth supralabial, and the first row of temporals); two first temporals, the upper twice the size of the lower; three second temporals, the upper twice longer than the two lower.
Specimen of Colobosaura modesta showing lateral coloration patter. Image given by Paul Smith (Fauna Paraguay). Additional photographs available at http://www.faunaparaguay.com/colobosauramodesta.html
Mental broad, wider (mm) than long (mm); postmental pentagonal, wider (mm) than long (mm), in contact with mental, first and second infralabials, and first pair of chin shields; two pairs of chin shields, the second larger than the first pair, and followed by elongated and oblique scales that separate the second pair of chin shields from the scales of the gular region; seven infralabials, the first the widest, and the fifth the longest.
Nuchal region with seven rows of paired imbricate scales; lateral sides of the neck with three to four irregular series of juxtaposed scales, and two imbricate located in the lowermost portion; seven paired rows of gular scales, first two rows irregular, and homogeneously arranged in pairs from the third to the seventh row.
Dorsal scales imbricate, 21 transversal rows between axilla and groin, wider at neck level, and narrower and homogeneously arranged in longitudinal rows on trunk; lateral scales similar to dorsals in the upper flanks, becoming wider towards the ventral region; sternal scale triangular, flanked by large rectangular scales in the clavicular region; four longitudinal rows of ventral scales; 26 scales around midbody; scales at insertion of limbs granular, except in the ventral region; all of tail with imbricate, elongated, hexagonal, and keeled scales.
Forelimbs covered with large, imbricate and smooth scales on the dorsal and lateral surfaces, being smaller on the ventral region of the limb; carpal region covered with large imbricate scales; palmar surface covered with granular juxtaposed scales; scales on fingers from I to V: 1/1-4/5-6/6-7/7-4/4; infradigital single lamellae under fingers from I to V: 2/2-8/8-10/10-11/12-6/5; fingers clawed except vestigial finger I.
Hind limbs medium-sized, imbricate, moderately keeled scales on the dorsal surface; anterior and posterior parts of the hind limbs with large, imbricate, and smooth scales; posterior part of hind limbs covered with granular juxtaposed scales on the thigh, and smooth medium-sized imbricate scales on the shank; tarsal region covered with large imbricate scales; plantar surface covered with granular juxtaposed scales; scales on toes from I to V: 3/3-4/4-8/8-10/10-6/(toe clipped as tissue sample); infradigital single lamellae under toes from I to V: 4/4-8/7-14/12-15/17-9/(toe clipped); toes clawed.
Dorsal surface of head Olive Clay Color (85) with Vandyke Brown (282) mottling on frontal and second supraocular and posteriorly, and a diffuse Vandyke Brown (282) line edging anterior margin of frontal and second supraocular and anterior scales; lateral parts of the head homogeneous Vandyke Brown (282); supralabials with Medium Neutral Gray (298) bars in the center interleaved with Cyan White (155) in the sutures; background color of mandibular region Cyan White (155) with Medium Neutral Gray (298) blotches on infralabials (one per scale) and second pair of chin shields; iris Burnt Umber (48); dorsal scales Mikado Brown (42), anteriorly (before forelimbs level) with Vandyke Brown (282) suffusions more concentrated near the laterals, and posteriorly (after forelimbs level) with faint irregular suffusions of Warm Sepia (40), more regularly present on the scales margins; lateral sides of the neck and body Vandyke Brown (282) with irregular Mikado Brown (42) speckles and blotches after forelimbs level, grading into a reticulated Vandyke Brown (282) and Mikado Brown (42) pattern near the groin; background ventral color Cyan White (155) with intrusions of Vandyke Brown (282) on the throat, and a faint mottling of Vandyke Brown (282) on the lateral rows of ventral scales; forelimbs mostly Vandyke Brown (282), Cyan White (155) restricted to the anteroventral regions; hind limbs Mikado Brown (42) with suffusion of Vandyke Brown (282) on the scales margins, and Cyan White (155) on the ventral region of the limb; tail background color Plumbeous (295) with Brownish Olive (292) suffusions on the anterior third of the organ, and Pale Greenish White (97) paravertebral spots located every two scales; iridescent hue all along the body.
(After five years in 70% ethanol): The general pattern remains the same, and the background Mikado Brown (42) color also remains; the darker parts of the body (lateral sides of neck and body) turned to Sepia (279); tail turned to Hair Color (277) on the dorsum, with the paravertebral spots faintly visible; ventral side of the head Smoky White (261); ventral side of the body Pale Buff (1).
The species is distributed in the Humid Chaco. The environment is basically a savanna composed of palms (Copernicia alba), native bunch grasses, and scattered islands of semideciduous temperate forest. The area is adapted to periodical floods from the Paraguay River. The locality of Puerto Max (former type locality of C. kraepelini) consists of a small village and cattle farm with intense anthropic pressure. The new specimens (
The tribe Iphisini was described recently by
From the genetic point of view there is no doubt that the neotype of Colobosaura kraepelini is different from C. modesta. The high genetic distance between these two species compared with the even lower genetic distance between some related genera (Table
The only previously known reference to a specimen of Colobosaura kraepelini was in the original description based on an individual from Puerto Max, and the species was never found again. Given the brevity of the original description the species was considered as synonym of C. modesta (
Biogeographically,
1 | Two longitudinal rows of ventral scales | 2 |
– | Four or six longitudinal rows of ventral scales | 4 |
2 | One pair of enlarged chin shields | Iphisa elegans |
– | Two pairs of enlarged chin shields | (Rondonops) 3 |
3 | Lateral neck scales smooth; 16–20 infradigital lamellae under toe IV | R. biscutatus |
– | Lateral neck scales keeled; 20–26 infradigital lamellae under toe IV | R. xanthomystax |
4 | Prefrontals absent | Stenolepis ridleyi |
– | Prefrontals present | 5 |
5 | Occipitals absent | Alexandresaurus camacan |
– | Occipitals present | 6 |
6 | Three pairs of chin shields | (Acratosaura) 7 |
– | Two pairs of chin shields | (Colobosaura) 8 |
7 | Lateral neck scales smooth and juxtaposed; dorsal scales slightly keeled (keel covers half of the scale) at midbody | A. mentalis |
– | Lateral neck scales keeled and imbricate; dorsal scales strongly keeled at midbody | A. spinosa |
8 | Ventrals immaculate; dark mottling on the external edge of gular shields | C. modesta |
– | Two central rows of ventral scales immaculate, and dark mottling on the two external rows; gular shields profusely mottled with dark | C. kraepelini |
We thank Dulcy Vázquez for help during fieldwork and Martha Motte (
Species | Voucher | GBAN | Locality |
---|---|---|---|
Acratosaura mentalis | MRT 906448 | AF420726 | Morro do Chapéu, BA, Br |
Alexandresaurus camacan | MD 1106 | AF420739 | Una, BA, Br |
Colobosaura kraepelini |
|
KY782646 | Altos, Cordillera, Pa |
Colobosaura modesta |
|
AY217953 | Niquelândia, GO, Br |
Iphisa elegans | MRT 977426 | AF420714 | Aripuanã, MT, Br |
Stenolepis ridleyi | -?- | EF405619 | -?- |
Cercosaura ocellata OG | MRT 977406 | AF420731 | Aripuanã, MT, Br |
Colobosaura kraepelini
PARAGUAY: Cordillera: San Bernardino, 50 metros del Lago Ypacarai (
Colobosaura modesta
PARAGUAY: Amambay: Parque Nacional Cerro Corá (