scholarly journals New distributional records of the Samana least gecko (Sphaerodactylus samanensis, Cochran, 1932) with comments on its morphological variation and conservation status

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10404
Author(s):  
Germán Chávez ◽  
Miguel A. Landestoy T ◽  
Gail S. Ross ◽  
Joaquín A. Ugarte-Núñez

We report here five new localities across the distribution of the lizard Sphaerodactylus samanensis, extending its current geographic range to the west, in the Cordillera Central of Hispaniola. We also report phenotypic variation in the color pattern and scutellation on throat and pelvic regions of males from both eastern and western populations, which is described below. Furthermore, based on these new data, we confirm that the species is not fitting in its current IUCN category, and in consequence propose updating its conservation status.

2016 ◽  
Vol 37 (3) ◽  
pp. 325-330 ◽  
Author(s):  
João Carlos Campos ◽  
Fernando Martínez-Freiría ◽  
Fábio Vieira Sousa ◽  
Frederico Santarém ◽  
José Carlos Brito

The West African crocodile (Crocodylus suchus) is an emblematic species from the Sahara-Sahel with scarce knowledge on distribution and conservation status. This study updated the knowledge on distribution, occupied habitats, population size, and factors that threaten C. suchus and its habitats in Mauritania. Five field expeditions to Mauritania (2011-2016), allowed the detection of 26 new localities, increasing by 27% the current number of all known locations (adding up to ). In most localities less than five individuals were observed, and in all visiting sites the number of observed individuals ranged from one to 23. Eleven threat factors were identified, being droughts and temperature extremes (100% localities affected) and water abstraction for domestic use and nomadic grazing (94%) the most frequent. These findings suggest that crocodiles are apparently vulnerable in Mauritania and that future local conservation strategies are needed to assure the continuity of its fragile populations and preserve their habitats.


1980 ◽  
Vol 58 (11) ◽  
pp. 2089-2095 ◽  
Author(s):  
John T. Rees ◽  
R. J. Larson

Morphological variation in the hydromedusan genus Polyorchis on the west coast of North America is analyzed in relation to gonad number, tentacle number, and radial canal diverticula number relative to the height of the bell. In specimens of Polyorchis examined, it is concluded that P. penicillatus (Eschscholtz, 1829) is highly variable morphologically over its known geographic range from Alaska to Baja California. Polyorchis montereyensis Skogsberg, 1948 is considered a synonym of P. penicillatus, and P. haplus Skogsberg, 1948, is retained as a valid species.


1995 ◽  
Vol 1 (1) ◽  
pp. 44 ◽  
Author(s):  
David J. Schmidly ◽  
Robert D. Bradley

ABSTRACT. We examined geographic and non-geographic variation in 23 quantitative characters of the cranium and body for samples of Peromyscus simulus from throughout the range of the species in Sinaloa and Nayarit, Mexico. Univariate statistical analyses indicated little non-geographic variation associated with either sex or age. Geographic variation was evident among samples, with northern, inland representatives averaging smaller in size and showing some degree of distinction from southern, coastal samples. However, the degree of this differentiation is not sufficient to warrant the delineation of subspecies. Available evidence suggest P. simulus has a relative narrow preference for wetland and riparian habitats within its geographic range. These habitats are subject to increased development in this region of Mexico, and, for this reason, the conservation status of the species should be carefully monitored in the future. RESUMEN. Examinamos la variación geográfica y no geográfica de 23 caracteres cuantitativos del cuerpo y cráneo de muestras de Peromyscus simulus a lo largo de la distribución de la especie en los estados de Nayarit y Sonora, México. Análisis estadísticos univariados mostraron poca variación no geográfica asociada con el sexo o la edad. Fue evidente la variación geográfica en muestras de representantes de islas al norte, siendo estas de menor tamaño en promedio y mostrando una ligera diferencia con respecto a las muestras costeras y más sureñas. Sin embargo, el grado de esta diferenciación no es suficiente para garantizar el límite de una subespecie. La evidencia disponible, sugiere que P. simulus tiene, relativamente, una preferencia por hábitats riparios y humedales dentro de su rango geográfico. El desarrollo de estos hábitats se ha incrementado en las últimas décadas; por esta razón, en el futuro el estado de conservación de la especie debe ser monitoreado cuidadosamente.Key words: Peromyscus simulus, morphological variation, Sinaloan mouse, Sinaloa, Nayarit, México.


Check List ◽  
2021 ◽  
Vol 17 (2) ◽  
pp. 407-414
Author(s):  
Pablo Javier Venegas ◽  
Luis Alberto García-Ayachi

We provide information on the distribution, natural history, and conservation status of Nymphargus mixomaculatus (Guayasamin, Lehr, Rodriguez & Aguilar, 2006), a species from central Peru which is currently considered as Critically Endangered. We report four new localities and extend the altitudinal distribution by 430 m and the geographic range by 513 km in a straight line northwest of the previous, only known locality. Furthermore, based on our new data and following the criteria and categories of the International Union for Conservation of Nature, we suggest that N. mixomaculatus should be recategorized as Vulnerable.


Diversity ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 251
Author(s):  
Adi Zweifler (Zvifler) ◽  
Michael O’Leary ◽  
Kyle Morgan ◽  
Nicola K. Browne

Increasing evidence suggests that coral reefs exposed to elevated turbidity may be more resilient to climate change impacts and serve as an important conservation hotspot. However, logistical difficulties in studying turbid environments have led to poor representation of these reef types within the scientific literature, with studies using different methods and definitions to characterize turbid reefs. Here we review the geological origins and growth histories of turbid reefs from the Holocene (past), their current ecological and environmental states (present), and their potential responses and resilience to increasing local and global pressures (future). We classify turbid reefs using new descriptors based on their turbidity regime (persistent, fluctuating, transitional) and sources of sediment input (natural versus anthropogenic). Further, by comparing the composition, function and resilience of two of the most studied turbid reefs, Paluma Shoals Reef Complex, Australia (natural turbidity) and Singapore reefs (anthropogenic turbidity), we found them to be two distinct types of turbid reefs with different conservation status. As the geographic range of turbid reefs is expected to increase due to local and global stressors, improving our understanding of their responses to environmental change will be central to global coral reef conservation efforts.


2003 ◽  
Vol 30 (5) ◽  
pp. 513 ◽  
Author(s):  
Theresa J. Nano ◽  
Cate M. Smith ◽  
Elizabeth Jefferys

The diet of the rare central rock-rat, Zyzomys pedunculatus, was assessed by microscopic analysis of 18 faecal pellet samples collected from four different sites in the west MacDonnell Ranges in the Northern Territory. Samples were collected from the four sites in summer (n = 13), one site in winter (n = 3), and two sites in spring (n = 2). Four major food categories were observed in the samples: seed, leaf, stem and insect. Seed was by far the most dominant food in the overall diet of Z. pedunculatus, making up 72% of identifiable particles, leaf was secondary (21%), while stem and insects contributed only 3% and 4% respectively. Although the sample size was small, no major seasonal shift between seed and invertebrate dominance was evident. Seed dominated the diet in both summer and winter, though winter seed consumption was lower (78% v. 58%). The level of seed consumption in the two spring samples was highly divergent (38% v. 93%), stressing the need for more samples to be collected from dry periods. Lowered rates of seed consumption during winter and in one of the spring samples were accompanied by increases in leaf consumption. Insect consumption remained low across all sampled seasons, suggesting that this species is not an omnivore. Rather, the dominance of seed in the diet suggests that Z. pedunculatus is primarily a granivore, a finding that has implications for the conservation status and management of this little-known species.


Zootaxa ◽  
2008 ◽  
Vol 1731 (1) ◽  
pp. 33 ◽  
Author(s):  
JONATHAN W. ARMBRUSTER ◽  
DONALD C. TAPHORN

Pseudancistrus reus is a new species from the Río Caroní (Río Orinoco drainage) of Venezuela known from two individuals. It differs from all other Pseudancistrus by having a color pattern consisting of alternating dark and light bars. In addition, it differs from all except P. genisetiger and P. papariae by having an incomplete mid-dorsal plate row and from P. genisetiger and P. papariae by having 18 contiguous mid-dorsal plates vs. 14 plates, a plateless break and then two more plates at the end of the caudal peduncle. The type locality of P. reus was submerged by the construction of the Caruachi dam, and is also the only known locality of the gymnotiform Sternarchorhynchus gnomus, making it imperative that the conservation status of these and other potential Caroní endemics be assessed. Pseudancistrus reus is the first species of Pseudancistrus sensu stricto from the Orinoco. Although the relationship of the species to other Pseudancistrus is unknown, P. reus may have gained access to the Orinoco either via stream capture between the Caroní and the Rio Uraricoera (Rio Branco – Rio Negro drainage) or via stream capture between the Caroní and either the Cuyuní or Mazaruni Rivers (Essequibo River drainage).key word: Siluriformes, Loricariidae, taxonomySe describe como especie nueva Pseudancistrus reus del río Caroní (cuenca del río Orinoco) en Venezuela, basada en dos ejemplares. Difiere de todas los demás Pseudancistrus en tener un patrón de pigmentación que consiste de barras claras alternando con oscuras. Además, difiere de todas los demás, menos P. genisetiger y P. papariae en tener la fila medio-dorsal de placas incompleta, y de P. genisetiger y P. papariae difiere en tener 18 placas medio-dorsales contiguas vs. 14 placas seguidas por una zona sin placas y luego dos placas más en el pedúnculo caudal). La localidad típica de P. reus fue sumergida por las aguas del embalse Caruachi. Ese sitio es también la localidad típica de Sternarchorhynchus gnomus, haciéndolo imprescindible evaluar el estado de conservación de estas dos especies más las otras endémicas del bajo Caroní. Pseudancistrus reus es la primera especies de Pseudancistrus sensu stricto de la cuenca del río Orinoco. Aunque desconocemos las relaciones con otras Pseudancistrus, P. reus puede haber ganado acceso al Caroní vía la captura de caños en las cabeceras del río Uraricoera-Branco-Negro o del río Cuyuní o Mazaruni, afluentes del río Essequibo.


Zootaxa ◽  
2009 ◽  
Vol 2223 (1) ◽  
pp. 25-47 ◽  
Author(s):  
ROGÉRIO BERTANI ◽  
CAROLINE SAYURI FUKUSHIMA

Avicularia diversipes (C. L. Koch 1842) known previously only from its original description is redescribed along with Avicularia sooretama sp. nov. and Avicularia gamba sp. nov. The three species are endemic to Brazilian Atlantic rainforest. With other Avicularia species, they share a procurved anterior eye row, slender embolus and medially folded spermathecae, whereas they have unusual characters, such as a very long and spiraled embolus (A. diversipes) and spermathecae with multilobular apex (A. sooretama sp. nov.). Furthermore, the three species lack a tibial apophysis in males and share a distinctive color pattern ontogeny that is not known in any other Avicularia species. The conservation status of the three species is discussed, especially with respect to endemism, illegal trafficking and habitat destruction. The creation of protected areas in southern State of Bahia, Brazil, is recommended, as well as the inclusion of these species in IUCN and CITES lists. Appendices with figures and species information are presented to facilitate correct specimen identification by custom officers, in order to limit illegal traffic.


Check List ◽  
2010 ◽  
Vol 6 (3) ◽  
pp. 414 ◽  
Author(s):  
Vanessa Barbisan Fortes ◽  
Elaine Maria Lucas ◽  
Vinícius Matheus Caldart

The Brazilian burrowing snake, Gomesophis brasiliensis, occurs in aquatic habitats such as swamps, from Minas Gerais and Distrito Federal until Rio Grande do Sul. In spite of this wide distribution, the species’ geographic range still remains unclear. This note reports the occurrence of G. brasiliensis in the municipality of Vargem Bonita, state of Santa Catarina, south Brazil, extending the species’ range ca. 80 km to the west in this state.


Check List ◽  
2018 ◽  
Vol 14 (6) ◽  
pp. 1115-1121
Author(s):  
Pamela Sánchez-Vendizú ◽  
Joseph A. Cook ◽  
James Wood ◽  
Jorge Salazar-Bravo

Proechimys pattoni da Silva, 1998 is one of the 3 small-bodied species of Proechimys and its geographic range is only known in western Brazil and eastern and southern Peru. However, based on morphological and molecular analyses, we report P. pattoni from the lowland forest of Bolivia (Pando: Rio Madre de Dios, near San Rosa). This is the first report of P. pattoni in Bolivia and extends its distributional range 315 km to the southeast in the Amazon biogeographic region of Bolivia, representing the southeastern most record. Furthermore, we document the karyotype (2n = 40 / FN = 56) and morphological variation in diagnostic characters.


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