Zootaxa 3616 (2): 119–134 (19 Feb. 2013)
A new acaremyid rodent (Hystricognathi: Octodontoidea) from the middle Miocene of Patagonia (South America) and considerations on the early evolution of Octodontoidea
MICHELLE ARNAL & MARÍA E. PÉREZ
Octodontoidea is the most speciose and ecologically diverse superfamily of caviomorph rodents. The systematic relationships of modern octodontoids is moderately accepted, however, the relationships of fossils (from the Eocene?–middle Miocene) are not clear. In recent years the hypothesis of a complex early evolution of the superfamily has emerged, with “basal octodontoids” representing different evolutionary lineages. The extinct family Acaremyidae may represent one such lineage, consisting of the genera Acaremys, Sciamys, Galileomys, and variably Platypittamys. In this work we describe a new octodontoid rodent recorded in post-Colloncuran? levels exposed at the locality of El Petiso, Northwest of Chubut Province, Argentina. Based on a systematic analysis of dental characters, we conclude that the new specimens correspond to a new species of Sciamys. Additionally, if the post-Colloncuran age for El Petiso is verified, the new species will extend the temporal range of the family Acaremyidae until, at least, the late middle Miocene, as well as the temporal range for the genus Sciamys from the Santacrucian SALMA. Our phylogenetic analyses corroborate the position of the new species as a member of Sciamys, and confirm that Acaremyidae represents an extinct family from Patagonian South America that lived until the middle Miocene. Massoiamys obliquus qualifies as morphological ancestor that pre-announces the octodontiform tooth pattern of octodontids. Thus, the octodontiform tooth pattern appears at least twice within the superfamily Octodontoidea.
Zootaxa 3616 (2): 135–150 (19 Feb. 2013)
A new species of the blind cave gudgeon Milyeringa (Pisces: Gobioidei, Eleotridae) from Barrow Island, Western Australia, with a redescription of M. veritas Whitley
HELEN K. LARSON, RALPH FOSTER , WILLIAM F. HUMPHREYS & MARK I. STEVENS
A new species of the eyeless eleotrid genus Milyeringa is described from wells sunk on Barrow Island, Western Australia.
Milyeringa justitia n. sp. is the third species of the genus to be named. Morphological data and cytochrome c oxidase subunit I (COI) DNA sequence data from a wide sample of localities at which the genus occurs was used to evaluate relationships and species limits. Milyeringa veritas is redescribed, and M. brooksi is synonymised with M. veritas. The unique form and ecology of these fishes, plus the threats to their survival, warrants immediate and continuing attention in management.
Zootaxa 3616 (2): 151–164 (19 Feb. 2013)
Cyrtodactylus dati, a new forest dwelling Bent-toed Gecko (Squamata: Gekkonidae) from southern Vietnam
NGO VAN TRI
A new species of Bent-toed Gecko, Cyrtodactylus dati sp. nov. is described from the secondary evergreen forests of Bu Dop District, Binh Phuoc Province, Vietnam. It differs from all other species of Indochinese and Thai-Malay Cyrtodactylus by having a maximum SVL of 70.1 mm (n=6); no distinct dark blotches on the head in adults; no continuous nuchal loop; a blotched dorsal pattern; 17–19 interorbital scales across the frontal bone; 23–26 scales in a straight line between eye and nostril; 42–48 rows of ventral scales between ventrolateral folds; 20–22 irregular, longitudinal rows of keeled tubercles at midbody between the ventrolateral folds; a series of five or six precloacal pores medially interrupted by one poreless scale in males; three or four femoral pores on each thigh in males; 4–7 enlarged scales beneath thighs; 12–13 subdigital lamellae on first toe; 18–19 subdigital lamellae on fourth toe; and small subcaudal scales.
Zootaxa 3616 (2): 173–189 (19 Feb. 2013)
A new species of Bachia Gray, 1845 (Squamata: Gymnophthalmidae) from the Eastern Brazilian Cerrado, and data on its ecology, physiology and behavior
MAURO TEIXEIRA JR, RENATO SOUSA RECODER, AGUSTÍN CAMACHO, MARCO AURÉLIO DE SENA, CARLOS ARTURO NAVAS & MIGUEL TREFAUT RODRIGUES
A new species of Bachia of the bresslaui group, Bachia geralista sp. nov., is described from Planalto dos Gerais, an old and partially dissected plateau extending along the Cerrados of Bahia, Minas Gerais and Tocantins states, Brazil. The new species is morphologically similar to B. bresslaui, with which it has been confused; however head scalation resembles other species from sandy spots within the Cerrado (B. psamophila and B. oxyrhina). Like in B. psamophila and B. oxyrhina, the shovel-shaped snout of the new species is highly prominent, a typical trait of psammophilous habits in other gymnophthalmids. The examination of specimens of B. bresslaui from several populations within the Cerrado revealed great variation among localities, leading to the reidentification of a specimen from Utiariti, Mato Grosso, previously referred to in the literature as the second record of B. bresslaui, as the recently described B. didactyla, suggesting that cryptic diversity might remain still undiscovered within this genus in the Cerrado. Despite occurring in a relatively open Cerrado, thermal physiology of Bachia geralista sp. nov. restricts its occurrence to shaded microhabitats within this habitat.
Morgan, C. C. and Álvarez, A. (2013), The humerus of South American caviomorph rodents: shape, function and size in a phylogenetic context. Journal of Zoology. doi: 10.1111/jzo.12017
South American caviomorph rodents comprise four major lineages encompassing wide taxonomic and ecological diversity, but the morphological diversity of their postcranial skeleton has not been thoroughly explored using phylogenetic comparative methods. The main goal of this work is to analyze their humerus using geometric morphometrics in a phylogenetic context and attempt to tease apart the influence of locomotory preferences and shared evolutionary history on morphological variation. We examined 28 genera in 9 families representing all major clades. Humeral shape was captured by 13 landmarks and four semilandmarks in 2D. In the morphospace of the first two principal components, most taxa were located near the origin along both axes. Fossorial octodontoids were apart from this central group. Most caviids were separated in one extreme of the morphospace; the specialized digging ctenomyid Ctenomys, the fossorial chinchillid Lagostomus and the generalized cavioid Cuniculus were located at the opposite end. Phylogenetic signal was significant. Regressions of shape on size were not significant; regression of shape on habit was significant for raw data and not significant after phylogenetic control. Humeral shape variation was primarily associated with the phylogenetic structure of the group; additionally, some morphological traits were associated with particular habits and interpreted as functional specializations. This association between humeral shape and both phylogeny and habit at different hierarchical levels suggests early ecomorphological diversification of caviomorphs.
Lučan, R. K., Weiser, M. and Hanák, V. (2013), Contrasting effects of climate change on the timing of reproduction and reproductive success of a temperate insectivorous bat. Journal of Zoology. doi: 10.1111/jzo.12021
We used long-term datasets to analyse (1) the patterns of covariation between basic climatic variables (temperature and rainfall) and the timing of reproduction and reproductive success; and (2) long-term trends in both reproductive parameters of a maternity colony of Daubenton’s bats Myotis daubentonii in South Bohemia, Czech Republic. The mean April temperature was the best predictor of the timing of reproduction. The higher the April temperature, the earlier the first neonates appeared. The mean date of first parturition was June 4, but it advanced significantly by c. 11 days between 1970 and 2012. Similarly, the mean April temperature increased over the study period by c. 2.7°C. Between 1999 and 2012, the mean reproductive success (proportion of reproductive females) was 74%, but varied between 33% (2009) and 93% (2006). It was negatively related to May–July precipitation. Thus, reproductive success was lower in years with increased rainfall. Given the published evidence that advancement in parturition is positively related to survival of juvenile bats rising spring temperatures may have a beneficial influence on the population dynamics of Daubenton’s bats. However, increased incidence of climatic extremes, such as excessive summer rainfall, may largely buffer this effect. Consequently, populations of temperate insectivorous bats may experience increasing environmental stress under continuing climate change.
Dill, A. K., Sanger, T. J., Battles, A. C. and Johnson, M. A. (2013), Sexual dimorphisms in habitat-specific morphology and behavior in the green anole lizard. Journal of Zoology. doi: 10.1111/jzo.12020
Species that occur in variable environments often exhibit morphological and behavioral traits that are specific to local habitats. Because the ability to move effectively is closely associated with structural habitat, locomotor traits may be particularly sensitive to fine-scale habitat differences. Anolis lizards provide an excellent opportunity to study the relationship between locomotion and natural perch use in the field, as laboratory studies have demonstrated that lizards that use broader perches develop longer limbs and have higher sprint speeds. We examined Anolis carolinensis (the green anole) in three habitats in close proximity. Our goals were to determine whether habitat-specific differences in hindlimb and toe morphologies occurred in a population in which perch size was variable but not manipulated, whether locomotor behaviors were associated with these morphologies, and whether habitat-specific traits differed between the sexes. We found that while juveniles in the three habitats did not differ in limb or toe morphology, adult females using broader perches had relatively longer limbs than females using narrower perches. Females also differed in toe length across habitats, but not in relation to perch diameter. Males, in contrast, exhibited differing growth patterns (allometry) in these traits, and marginal differences in locomotor behavior. Together, these results suggest that sex-specific responses in morphology and behavior, consistent with experimental observations of phenotypic plasticity, provide a mechanism for refining local habitat use.
Phylogeny of the Dactyloa Clade of Anolis Lizards: New Insights from Combining Morphological and Molecular Data
María Del Rosario Castañeda and KEVIN DE QUEIROZ
Bulletin of the Museum of Comparative Zoology 2013 160 (7), 345-398
We present a phylogenetic analysis of the Dactyloa clade of Anolis lizards, based on morphological (66 characters of external morphology and osteology) and molecular (4,700 bases of mitochondrial and nuclear DNA) data. Our set of morphological characters includes some that exhibit continuous variation and others that exhibit polymorphism within species; we explored different coding methods for these classes of characters. We performed parsimony and Bayesian analyses on morphology-only and combined data sets. Additionally, we explicitly tested hypotheses of monophyly of: 1) Dactyloa including Phenacosaurus, 2) Dactyloa excluding Phenacosaurus (as traditionally circumscribed), 3) taxa previously ranked as series or species groups described based on morphological characters, and 4) clades inferred from molecular data. The morphological data alone did not yield Dactyloa or any of the previously recognized series described based on morphological characters; only the Phenacosaurus clade (as delimited based on molecular data) was inferred with the morphological data, and only in the parsimony analysis. In contrast, Dactyloa was inferred as monophyletic with the combined data set, although topology tests failed to reject the hypothesis of non-monophyly. Additionally, five clades inferred based on molecular data (eastern, latifrons, Phenacosaurus, roquet, and western) were inferred with the combined data sets with variable support and including additional species for which molecular data were not available and which have geographic distributions that conform to those of the clades in which they were included. Of the previously recognized taxa based on morphological characters, only the roquet series, which corresponds in species composition to the roquet clade, was inferred with the combined data. Topology tests with the combined data set rejected the monophyly of the aequatorialis, latifrons (as traditionally circumscribed), and punctatus series but not that of the tigrinus series and Phenacosaurus (as traditionally circumscribed). Our phylogenetic analyses and topology tests indicate that a new taxonomy for Dactyloa is warranted; we therefore present a revised taxonomy based on the results our phylogenetic analyses and employing phylogenetic definitions of taxon names.
Armfield et al. (2013) Development and evolution of the unique cetacean dentition. PeerJ 1:e24 http://dx.doi.org/10.7717/peerj.24
The evolutionary success of mammals is rooted in their high metabolic rate. A high metabolic rate is sustainable thanks to efficient food processing and that in turn is facilitated by precise occlusion of the teeth and the acquisition of rhythmic mastication. These major evolutionary innovations characterize most members of the Class Mammalia. Cetaceans are one of the few groups of mammals in which precise occlusion has been secondarily lost. Most toothed whales have an increased number of simple crowned teeth that are similar along the tooth row. Evolution toward these specializations began immediately after the time cetaceans transitioned from terrestrial-to-marine environments. The fossil record documents the critical aspects of occlusal evolution of cetaceans, and allows us to pinpoint the evolutionary timing of the macroevolutionary events leading to their unusual dental morphology among mammals. The developmental controls of tooth differentiation and tooth number have been studied in a few mammalian clades, but nothing is known about how these controls differ between cetaceans and mammals that retain functional occlusion. Here we show that pigs, a cetacean relative with regionalized tooth morphology and complex tooth crowns, retain the typical mammalian gene expression patterns that control early tooth differentiation, expressing Bmp4 in the rostral (mesial, anterior) domain of the jaw, and Fgf8 caudally (distal, posterior). By contrast, dolphins have lost these regional differences in dental morphology and the Bmp4 domain is extended into the caudal region of the developing jaw. We hypothesize that the functional constraints underlying mammalian occlusion have been released in cetaceans, facilitating changes in the genetic control of early dental development. Such major developmental changes drive morphological evolution and are correlated with major shifts in diet and food processing during cetacean evolution.
Steffen R. Hage, Tinglei Jiang, Sean W. Berquist, Jiang Feng, and Walter Metzner
Ambient noise induces independent shifts in call frequency and amplitude within the Lombard effect in echolocating bats PNAS 2013 ; published ahead of print February 19, 2013, doi:10.1073/pnas.1211533110
The Lombard effect, an involuntary rise in call amplitude in response to masking ambient noise, represents one of the most efficient mechanisms to optimize signal-to-noise ratio. The Lombard effect occurs in birds and mammals, including humans, and is often associated with several other vocal changes, such as call frequency and duration. Most studies, however, have focused on noise-dependent changes in call amplitude. It is therefore still largely unknown how the adaptive changes in call amplitude relate to associated vocal changes such as frequency shifts, how the underlying mechanisms are linked, and if auditory feedback from the changing vocal output is needed. Here, we examined the Lombard effect and the associated changes in call frequency in a highly vocal mammal, echolocating horseshoe bats. We analyzed how bandpass-filtered noise (BFN; bandwidth 20 kHz) affected their echolocation behavior when BFN was centered on different frequencies within their hearing range. Call amplitudes increased only when BFN was centered on the dominant frequency component of the bats’ calls. In contrast, call frequencies increased for all but one BFN center frequency tested. Both amplitude and frequency rises were extremely fast and occurred in the first call uttered after noise onset, suggesting that no auditory feedback was required. The different effects that varying the BFN center frequency had on amplitude and frequency rises indicate different neural circuits and/or mechanisms underlying these changes.
Zootaxa 3616 (3): 201–238 (20 Feb. 2013)
Checklist of lizards and amphisbaenians of Argentina: an update
LUCIANO JAVIER AVILA, LORENA ELIZABETH MARTINEZ & MARIANA MORANDO
We update the list of lizards of Argentina, reporting a total of 261 species from the country, arranged in 27 genera and 10 families. Introduced species and dubious or erroneous records are discussed. Taxonomic, nomenclatural and distributional comments are provided when required. Considering species of probable occurrence in the country (known to occur in Bolivia, Brazil, Chile and Paraguay at localities very close to the Argentinean border) and still undescribed taxa, we estimate that the total number of species in Argentina could exceed 300 in the next few years.
Zootaxa 3616 (3): 239–252 (20 Feb. 2013)
Phylogenetic relationships and description of a new upland species of Bent-toed Gecko (Cyrtodactylus Gray, 1827) of the C. sworderi complex from northeastern Peninsular Malaysia
L. LEE GRISMER, SHAHRUL ANUAR, MOHD ABDUL MUIN, EVAN S. H. QUAH & PERRY L. WOOD, JR.
Molecular and morphological analyses indicate that a new upland species of the Cyrtodactylus sworderi complex, C.
tebuensis sp. nov. from Gunung Tebu, Terengganu, Malaysia is most closely related to C. sworderi and together they form the sister lineage to C. quadrivirgatus. Cyrtodactylus tebuensis sp. nov. is differentiated from all other species of Sundaland Cyrtodactylus on the basis of having the unique combination of large, conical, keeled body tubercles; tubercles present on top of head, occiput, nape, and limbs, and extending posteriorly beyond base of tail; 43–51 ventral scales; no transversely enlarged, median subcaudal scales; proximal, subdigital lamellae transversely expanded; 17–21 subdigital lamellae
on fourth toe; an abrupt transition between posterior and ventral femoral scales; enlarged femoral scales; no femoral or precloacal pores; no precloacal groove; body bearing four wide, bold, dark brown stripes (lateral stripe on each flank and a pair of paravertebral stripes); and a pairwise sequence divergence of 13.0% from its closest relative C. sworderi
based on the mitochondrial gene ND2. Cyrtodactylus tebuensis sp. nov. is the first endemic upland species of gekkonid from northeastern Peninsular Malaysia and underscores the necessity for additional field work in all upland systems.