Corresponding author: Luis M. P. Ceríaco (
Academic editor: A. Crottini
African pygmy toads of the genus
Ceríaco LMP, Marques MP, Bandeira S, Agarwal I, Stanley EL, Bauer AM, Heinicke MP, Blackburn DC (2018) A new earless species of
African pygmy toads of the genus
There are currently ten recognized species in the genus
Known distribution of the nine currently accepted
Bibliographic and confirmed museum records of the different
Despite being among the better explored regions in Angola, there are still new distributional records and undescribed species of reptiles and amphibians being discovered in the coastal lowlands of Namibe and Benguela provinces (
During recent field research in Angola, we collected specimens representing several species of
Specimens collected for this study were preserved in 10% neutral buffered formalin in the field and transferred to 70% ethanol for storage. Liver tissue was removed before formalin fixation and preserved in either 95% ethanol or RNA Later. Specimens are deposited in the Florida
Portions of the mitochondrial 16S gene and nuclear RAG-1 gene were sequenced for newly collected specimens of
Sequence assembly was performed using BioEdit 7.0.5.3 (
A maximum likelihood phylogenetic analysis was performed using IQ-TREE 1.5 (
Sample identifications and GenBank accession numbers of sequences used in phylogenetic analyses. Specimen ID acronyms:
Species | Specimen ID | 12S | 16S | CO1 | ND2 | CXCR4 | RAG1 |
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n/a | – |
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n/a |
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n/a |
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VG001 |
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Osteological data were obtained from six specimens of the Serra da Neve population, 18 additional
Measurements and external morphological data followed the standardized protocols presented by
Molecular phylogenetic and morphological analyses suggest that the pygmy toads collected from the Serra da Neve represent an undescribed species of
Maximum likelihood tree of the genus
Morphologically, the Serra da Neve taxon is typical of
Comparison between the
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31 mm | 40 mm | 37 mm | 37 mm | 36 mm | 33 mm | 28 mm | 43 mm | 30 mm | 46 mm |
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Inconspicuous, flattened | Conspicuous, flattened | Conspicuous to completely flattened | Conspicuous, with well defined edges but flattened | Inconspicuous, flattened | Inconspicuous, of constant width, with outer edge straight and not extending below pupil | Inconspicuous to hardly discernible | Inconspicuous, flattened | Inconspicuous to hardly discernible | Inconspicuous to hardly discernible |
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Not present | Present, conspicuous, diameter smaller than internarial distance | Present, inconspicuous | Present, inconspicuous | Present, inconspicuous | Present, conspicuous, diameter smaller than internarial distance | Present, inconspicuous | Present, conspicuous, diameter smaller than internarial distance | Present, inconspicuous | Present, conspicuous, diameter equal or bigger than internarial distance |
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Granular | Smooth | Smooth | Granular | Granular | Smooth | Smooth | Granular | Granular | Smooth |
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Granular | Smooth to slightly granular | Smooth to slightly granular | Granular | Slightly granular | Granular | Very granular | Smooth to slightly granular | Smooth to slightly granular | Smooth to slightly granular |
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Not present | Usually not present | Not present | Not present | Present | Present | Usually present | Usually not present | Not present | Not present |
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Dark brown with coppery to brown mottling and dark brown blotches especially in anterior regions , and a pale scapular patch | Light to dark brown, with small dark blotches and pale scapular patch | Brown to reddish-brown with light and dark marking | Olive-brown with symmetrical to irregular dark blotches, dark interorbital band | Grey to brown with orange and reddish markings, pale scapular patch, single or a pair of patches in lower back | Three pairs of dark patches with dark interorbital band, light colored scapular patch with pale projections upper eyelids | Dark grey and with a pale scapular patch | Light grey to brown, with small scattered dark blotches, pale scapular patch, sometimes with a single or a pair of patches in lower back | Light grey to brown, with small scattered dark blotches, pale scapular patch, sometimes with a single or a pair of patches in lower back | Light-grey to brown, with dark patches in the scapular and poster parts of the dorsum, top of the head cream |
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Cream-colored, juveniles whitish with distinct black blotches | Immaculate | Immaculate | Yellowish-white | Whitish with distinct black blotches | Cream-colored | Pale without marking | Immaculate, occasionally with black blotches or spots | Cream-colored | Immaculate |
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Toes without a margin of web, webbing between toes vestigial | Scanty, only reaching base of fourth toe | Toes with distinct margin of webbing | Moderately well developed, three to three and a half phalanges of longest toe free of webbing | Toes scantly webbed, two segments of the third toe are free of web | Toes scantly webbed with serrated margins, broad web between toes three and four | Two or three segments of the longest toe free of webbing | Scantly webbed | Toes without a margin of web, webbing between toes vestigial | Toes without a margin of web, webbing between toes vestigial |
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Double | Usually double | Double | Well defined, usually double | Usually double | Usually double | Usually double | Usually double | Single | Single, except distal tubercle of third finger |
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Inner three times bigger than outer | Smaller than outer but substantially larger than other palmer tubercles. | Inner similar in size or smaller than outer | Inner bigger than the outer | Inner three times bigger than outer | Inner elongated towards the medial surface below base of first finger. Outer , rounded to triangular shape. Inner two to three times smaller than the outer | Inner not present, but a tubercle at base of first finger may be slightly larger than other tubercles. Outer markedly enlarged | Inner three times bigger than outer | Inner two to three times smaller than outer | Inner bigger than the outer |
A female,
A male
Small (
Ventral and dorsal view of the holotype (
Ventral view of the right hand and left foot of the holotype (
Measurements of the type series of
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Type status | Holotype | Paratype | Paratype | Paratype | Paratype | Paratype |
SEX | Female | Male | Juvenile | Female | Male | Male |
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9.9 | 9.5 | 8.9 | 9.2 | 9.9 | 10.3 |
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31.4 | 31.3 | 29.7 | 28 | 33.7 | 30.0 |
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11.7 | 12.1 | 10.9 | 11.6 | 12.3 | 12.5 |
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3.2 | 3.2 | 3.3 | 3.3 | 4.5 | 4.2 |
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8.7 | 8.1 | 8.8 | 9.1 | 11.7 | 10.6 |
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2.8 | 2.9 | 2.7 | 2.9 | 3.0 | 3.0 |
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1.9 | 2.3 | 2.2 | 1.9 | 2.5 | 2.0 |
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2.6 | 2.2 | 2.4 | 2.6 | 2.8 | 2.7 |
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11.8 | 12.0 | 11.7 | 11.7 | 12.1 | 12.5 |
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11.6 | 11.0 | 10.7 | 11.2 | 12.0 | 13.0 |
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3.9 | 3.7 | 4.2 | 4.5 | 3.9 | 4.0 |
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7.4 | 7.1 | 6.8 | 6.9 | 7.4 | 7.2 |
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7.2 | 6.0 | 6.5 | 6.6 | 6.7 | 7.8 |
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2.8 | 2.2 | 2.6 | 2.9 | 2.2 | 2.4 |
FIN4L | 4.6 | 4.9 | 4.0 | 4.5 | 4.7 | 4.3 |
TOEL4L | 5.9 | 7.3 | 6.2 | 6.7 | 7.7 | 6.1 |
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1.7 | 1.8 | 1.0 | 1.2 | 1.5 | 1.4 |
Skin of venter with evenly scattered miniscule asperities; skin of gular region smooth; skin of limbs, dorsal and dorsolateral surface of head and body with scattered tubercles, being larger on dorsum; inconspicuous and flattened parotoid glands, elliptical, and weakly elevated, placed dorsolaterally and extending from posterior corner of mouth to level of axilla.
Limbs and digits well-developed; digits of both manus and pes stout; tarsal fold not present; relative length of fingers: III > I > IV = II; finger tips not expanded, but with rounded tips; fingers with rounded, prominent double subarticular tubercles; two palmar tubercles distinct and widely separated from one another, one at ventromedial surface of first finger and other at proximal plantar surface, latter being about 4 times larger than first; webbing between manual digits absent; relative length of toes IV > III > II > I = V; toe tips slightly expanded; toes with prominent, single, and subarticular tubercles; webbing between toes vestigial, not reaching first joint of first phalanx; prominent and globular inner metatarsal tubercle, length 50% of first toe length; tarsal tubercle prominent and projecting, near medial edge and positioned at distal fourth of tarsus.
In life, dorsal ground color dark brown with coppery to brown mottling and dark brown blotches especially in anterior regions (Figure
Photograph in life of
The coloration of the remaining paratypes do not differ in any important details from those of the holotype. Measurements of the remaining type series in Table
Based on CT scan of
High-resolution Computed Tomography reconstructions showing the skeleton of the holotype (
There are eight distinct, procoelous, non-imbricating presacral vertebrae that are not synostosed. The atlas lacks transverse processes and has widely separated cotyles. The sacrum is procoelous with laterally expanded transverse processes. No sesamoid is observed at the sacroiliac joint. The urostyle is long and thin with a weakly developed dorsal ridge.
The pectoral girdle is fermisternal with widely spaced and slender coracoids. The clavicles are slender, nearly reaching one another. The scapulae are stout, directed laterally but strongly curving dorsally at their lateral extent. Neither an ossified sternum nor omosternum is present.
The pelvic girdle comprises the ilium, pubis, and ischium, which are not synostosed to one another. The acetabulum is incompletely ossified. The shaft of the ilium is long and slender, lacking a dorsal crest, and with a small prominent dorsal protuberance. The synostosed ischia form a broad posteriorly directed plate.
The radioulna is shorter than the humerus. The radiale and ulnare are large and subequal in size, though the other carpals are difficult to distinguish as they are incompletely ossified. The phalangeal formula for the manus is 2–2–3–3, and there is both a single ossified prepollex and a small palmar sesamoid. The tips of the terminal manual phalanges are weakly expanded into small knobs. The tibiofibula is slightly shorter than the femur. There are two small distal tarsals. The phalangeal formula for the pes is 2–2–3–4–3 and there is a single small ossified prehallux and a plantar sesamoid. The tips of the terminal pedal phalanges are weakly expanded as in the fingers.
The species is currently only known from the Serra da Neve Inselberg (Figs
Southern view of the base of the Serra da Neve Inselberg (
The specific name
Despite several decades of interest in African pygmy toads (e.g., Poyton 1964,
Unlike most African anuran taxa, the species diversity of
Bibliographic (
In addition to
The osteology of both
Comparisons of the skulls of
The Angolan Ministry of Environment and
CT-Scan settings
Data type: specimens data
Explanation note: CT-Scan settings for the different specimens used in this study.