Craugastor pygmaeus
Creators: name: Jameson, Tom J. M.
name: Streicher, Jeffrey W.
name: Manuelli, Luigi
name: Head, Jason J.
name: Smith, Eric N.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Amphibia
Anura
Craugastoridae
Craugastor
Craugastor pygmaeus

description: <i>Craugastor pygmaeus</i> (Taylor 1936) <i>Eleutherodactylus pygmaeus</i> Taylor 1936:352. Holotype female (UIMNH 16125) from ‘‘one mile north of Rodriguez Clara, Veracrux, Mexico.’’ [Examined]. <i>Microbatrachylus albolabris</i> Taylor 1940:502. Holotype female (FMNH 100071) from ‘‘two miles west of Córdoba, Veracruz, Mexico.’’ [Examined]. <i>Microbatrachylus pygmaeus</i> (Taylor): Taylor 1940:500. <i>Microbatrachylus minimus</i> Taylor 1940:507. Holotype male (FMNH 100323) from ‘‘Agua del Obispo, Guerrero, Mexico.’’ [Examined]. <i>Microbatrachylus imitator</i> Taylor 1942:70. Holotype female (USNM 115508) from ‘‘La Esperanza, Chiapas, Mexico.’’ [Examined]. <i>Craugastor pygmaeus</i> (Taylor): Crawford and Smith 2005:536. <b>Diagnosis.</b> —Based on 37 specimens. Aspecies of <i>Craugastor</i> distinguished by the following combination of characters: (1) small adult size (mean SVL <i>¼</i> 13.5 mm [SD <i>¼</i> 1.77], <i>n ¼</i> 29); (2) full ossification of skeletal elements in adults; (3) lack of posterolateral projection of frontoparietal; (4) lack of vomerine odontophores; (5) presence or absence of raised tubercles on eyelids; (6) supratympanic fold absent or poorly developed; (7) face flank barred canthus and jaws (rarely dark and blotched), no canthal stripe; (8) one (or two fused) postrictal tubercles; (9) gular region pigmentation present or absent; (10) dorsal surface two-toned usually with dark suprascapular ^^shape, or striped and with pale middorsal stripe; (11) variable middorsal ridge; (12) dorsum smooth or with only some large scattered tubercles; (13) body flank barred darker anteriorly, slightly shagreened to smooth; (14) inguinal glands present and axillary glands absent in adults; (15) when leg adpressed to body, heel reaches between eye and slightly beyond tip of snout; (16) outer tarsal ridge smooth, no raised fringe; (17) finger and toe pads round, expanded; (18) inner metatarsal tubercle larger than outer metatarsal tubercle. <b>Comparisons.</b> — <i>Craugastor pygmaeus</i> can be differentiated from <i>C. candelariensis, C. cueyatl, C. hobartsmithi,</i> and <i>C. portilloensis</i> by equal sizes of the inner and outer metatarsal tubercles (unequal sizes in <i>C. pygmaeus</i>). It can be differentiated from <i>C. mexicanus, C. montanus, C. omiltemanus, C. polaclavus, C. rubinus,</i> and <i>C. saltator</i> by the presence of a posterolateral projection of the frontoparietal (absent in C. <i>pygmaeus</i> <i>;</i> Fig. 26C). <i>Craugastor pygmaeus</i> is most similar to <i>C. bitonium</i> (in morphology, osteology, and genetic distance), but may be differentiated from this taxon by the condition of the outer tarsal ridge, which is smooth in <i>C. pygmaeus</i> versus 1–6 small tubercles in <i>C. bitonium</i>. <b>Description.</b> —In previous literature, described as smallbodied (‘‘diminutive’’) and short-limbed, with unequal inner and outer metatarsal tubercle sizes; distinct subarticular tubercles; barely visible supernumerary tubercles; no vomerine odontophores (Taylor 1936); rounded canthus; two palmar tubercles (Taylor 1942). Downloaded From: https://bioone.org/journals/Herpetological-Monographs on 04 May 2022 Holotype (UIMNH 16125) ~ 18 mm SVL. Among select specimens that we examined, we observed short, rounded snout (naris–snout <i>¼</i> 0.78 mm, SD <i>¼</i> 0.14, <i>n ¼</i> 29; 5.8% SVL); long eye–nostril distance (1.19 mm, SD <i>¼</i> 0.24, <i>n ¼</i> 29; 8.9% SVL); some specimens with single palmar tubercle; relative finger lengths III&gt; IV&gt; II <i>¼</i> I; relative toe lengths IV &lt;III &lt;V &lt;II &lt;I; color pattern in life variable (Fig. 33). <b>Distribution.</b> —Widely distributed throughout lowland to intermediate localities in the states of Chiapas, Puebla, Oaxaca, and Veracruz (also possibly Tabasco, Mexico, and western Guatemala) from near sea level to 2000 m (Fig. 6). Canseco Márquez and Gutiérrez Mayén (2010) report <i>C. pygmaeus</i> occurs in the forests adjacent to the Tehuacán– Cuicatlán Valley in Puebla and Oaxaca. The western range edge of <i>C. pygmaeus</i> is uncertain; we examined one specimen (UTA A-66131) a male with pigmented testes, from San Vicente de Benitez (17.290618N, 100.279558W, 951 m), Guerrero, collected 17 June 2004, that appears referable to <i>C. pygmaeus</i>. <b>Diet.</b> —One male specimen (UTA A-64263, determined by the presence of pigmented testes), was found to contain ants (Formicidae) in its stomach. <b>Phylogenetics.</b> — <i>Craugastor pygmaeus</i> was inferred to be the sister taxon of <i>C. bitonium</i> with high support in the concatenated analyses (ML <i>¼</i> 99; BAYES <i>¼</i> 1.0; Fig. 3). This sister relationship was also recovered in both mtDNA and nDNA analyses, although with lower support in the nDNAonly analyses (ML <i>¼</i> 54, BAYES <i>¼</i> 0.67; Figs. 4 and 5). <i>Craugastor pygmaeus</i> is separated from <i>C. bitonium</i> by a <i>P</i> - distance of 4.7% (Table 4). <b>Remarks.</b> —The skull of <i>C. pygmaeus</i> is similar to <i>C. hobartsmithi</i> and <i>C. montanus,</i> with more posteriorly placed anterior suture of the frontoparietal and prootic than in other species. Despite how common this species is in most museum collections, we know very little about its natural history, including reproductive behavior, call, and diet. This species likely co-occurs with <i>C. candelariensis, C. polaclavus</i> and <i>C. portilloensis</i> in southcentral Oaxaca and (possibly) <i>C. bitonium</i> in central Guerrero. It may overlap with (1) <i>C. montanus</i> in Chiapas, (2) <i>C. mexicanus</i> at intermediate elevations of the Sierra Madre del Sur and Sierra Madre Oriental (Fig. 7), and (3) <i>C. hobartsmithi</i> in central and western Guerrero. Males likely have larger tympana than do females (Figs. 13 and 33).
description: Published as part of <i>Jameson, Tom J. M., Streicher, Jeffrey W., Manuelli, Luigi, Head, Jason J. &amp; Smith, Eric N., 2022, Miniaturization in Direct-Developing Frogs from Mexico with the Description of Six New Species, pp. 1-48 in Herpetological Monographs 36 (1)</i> on pages 34-35, DOI: 10.1655/0733-1347-36.1.1, http://zenodo.org/record/6518587
description: {"references": ["Taylor, E. H. 1936 [1937]. New species of amphibia from Mexico. Transactions of the Kansas Academy of Science 39: 349 - 363.", "Taylor, E. H. 1940. Herpetological miscellany No. I. University of Kansas Science Bulletin 26: 489 - 571.", "Taylor, E. H. 1942. New tailless Amphibia from Mexico. University of Kansas Science Bulletin 28: 67 - 89.", "Crawford, A. J., and E. N. Smith. 2005. Cenozoic biogeography and evolution in direct-developing frogs of Central America (Leptodactylidae: Eleutherodactylus) as inferred from a phylogenetic analysis of nuclear and mitochondrial genes. Molecular Phylogenetics and Evolution 35: 536 - 555.", "Canseco Marquez, L., and M. G. Gutierrez Mayen. 2010. Anfibios y Reptiles del Valle Tehuacan-Cuicatlan. Comision Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO), Mexico."]}