scholarly journals The relationship between forest fragmentation and the potential geographical distribution of psittacids (Psittaciformes: Psittacidae) in the Yucatan Peninsula, Mexico

2017 ◽  
Vol 65 (4) ◽  
pp. 1470
Author(s):  
Alexis Herminio Plasencia Vázquez ◽  
Griselda Escalona Segura ◽  
Yarelys Ferrer Sánchez

Parrots are a seriously threatened group because of the illegal pet trade, their habitat fragmentation and the destruction of tropical forests. This study aimed to determine the relationship between forest fragmentation and the geographic potential distribution of parrot species in the Yucatan Peninsula, Mexico. The research was carried out in the Mexican portion of the Yucatan Peninsula Biotic region, which includes the states of Campeche, Quintana Roo and Yucatan. We worked with the eight species of psittacids that inhabit the selected areas: Eupsittula nana, Amazona albifrons, Amazona xantholora, Amazona autumnalis, Pionus senilis, Pyrilia haematotis, Amazona oratrix and Amazona farinosa. For these species, we used the potential geographical distribution maps that were obtained through the Maximum Entropy algorithm, published in 2014. To measure the levels of forest fragmentation in the Peninsula, we employed the land use and vegetation maps from series IV (2007-2010) of the National Institute of Statistics and Geography. We calculated different landscape metrics at 100 sites randomly distributed within the predicted presence and absence areas for the species. Multivariate methods were used to shorten dimensionality in the analysis, as well as to explore the observed patterns. We did not find any pattern regarding the number of variables that contribute to the logistic regression models (LR) and the size of the parrots’ potential geographical distribution area within the Peninsula. For Pyrilia haematotis and Amazona oratrix, the fragmentation variables used did not seem to have any relationship with their potential geographical distribution in the Peninsula (intersection, Pr < 0.0001). Only for Eupsittula nana, Amazona xantholora and Pionus senilis, we found that the mean patch edge, the mean shape index and the mean perimeter-area ratio were important to determine their potential distribution patterns, respectively; and, in general, the variables indicated the preferences of these parrots to occupy larger habitat patches. Parrots must be given a special care and protection within the states of Campeche and Quintana Roo, since there are areas with high parrot diversity and are importantly affected by human activities. The best recommendation for managers and users of protected areas within the Yucatan Peninsula is that extensive areas of forest should be maintained in order to guarantee the suvival of psittacid populations.

2020 ◽  
Vol 40 (3) ◽  
pp. 221-229
Author(s):  
Sergio A Benítez ◽  
Thomas M Iliffe ◽  
Salvador Martínez ◽  
Juan Carlos Ojeda ◽  
José Luis Villalobos ◽  
...  

Abstract Although the larval development of epigean palaemonid shrimps has been studied extensively, only a few investigations deal with stygobitic species. We present the larval development of the cave-adapted Creaseria morleyi (Creaser, 1936) from anchialine caves in the Tulum area, Quintana Roo, Yucatán Peninsula, Mexico. Through the discovery of a series of larvae at different stages of development, we constructed a sequence extending through the juvenile stage. The larvae (41) were captured in plankton tows above the halocline at depths ranging between 11 and 15 m during eight surveys conducted between 2013 and 2016. Six larval stages and the first juvenile were identified; however, it is clear from the gradual modification of structures and appendages that more stages exist. The first larvae have a large quantity of vitellum and do not feed, since they have only rudimentary, and possibly non-functional, mouthparts. In the sixth stage and the juvenile, when the stages have no vitellum left, the mouthparts, chelae, and pleopods develop entirely. A comparison with other palaemonid shrimps suggests that C. morleyi has a greater affinity with those palaemonid species possessing extended larval development as is seen in species of MacrobrachiumSpence Bate, 1868.


Zootaxa ◽  
2012 ◽  
Vol 3154 (1) ◽  
pp. 61 ◽  
Author(s):  
FERNANDO ALVAREZ ◽  
THOMAS M. ILIFFE ◽  
BRETT GONZALEZ ◽  
JOSÉ LUIS VILLALOBOS

A new species of Triacanthoneus Anker, 2010 is described from an anchialine cave near Akumal, Quintana Roo, Mexico.Triacanthoneus akumalensis sp. nov., is the fourth species in the genus and can be distinguished from the previously de-scribed species by the position of the sharp lateral teeth on the carapace, the length and shape of the rostrum, the eyes beingcompletely concealed by the carapace, the dentition of the major chela fingers, and the shape of the telson. The presenceof a pleural process in the new species represents a new character for the genus. The description of T. akumalensis sp. nov. increases the number of caridean genera having representatives in the anchialine systems of the Yucatan Peninsula to 11.


Phytotaxa ◽  
2016 ◽  
Vol 268 (3) ◽  
pp. 209 ◽  
Author(s):  
SHUANG-XI YAN ◽  
HUI-JIE LIU ◽  
LE-LE LIN ◽  
SHUAI LIAO ◽  
JIN-YU LI ◽  
...  

The morphologically based taxonomic status of Clematis acerifolia var. elobata has been controversial. This study used two nuclear (ITS and ETS) and six plastid (rps16, rpl16, accD, trnS-trnG, atpB-rbcL, and trnV-atpE) molecular markers, and a DNA barcoding analysis to address the taxonomic status of C. acerifolia var. elobata and the relationship among other Clematis species. Our results showed that the discrimination power of ITS, ETS, and atpB-rbcL was better than that of the other tested DNA regions. When all tested sequences combined, most of the sampled taxa were resolved. Though the two taxa are closely related, they have differentiated clearly and formed two clades respectively. The mean divergence of the two taxa was 0.78%, which was higher than closely related Clematis species such as C. heracleifolia and C. pinnata (0.50 %). Considering molecular divergence, morphological differences, and distribution area, we raised C. acerifolia var. elobata to species level.


Acarologia ◽  
2019 ◽  
Vol 59 (1) ◽  
pp. 111-114
Author(s):  
Lucia Montes-Ortiz ◽  
Tom Goldschmidt ◽  
Manuel Elías-Gutiérrez

For the first time a parasitic relationship between a water mite larva and a Cladocera is found and documented by scanning electron microscope (SEM) imaging. A Unionicolidae larva (cf. Unionicola) has been found attached to a Bosmina tubicen (Cladocera) collected in a karst sinkhole (cenote) in the southeast of the Yucatán Peninsula (México).


1986 ◽  
Author(s):  
James Francis Lynch ◽  
Smithsonian Environmental Research Center

PLoS ONE ◽  
2020 ◽  
Vol 15 (1) ◽  
pp. e0227444
Author(s):  
Mark Hubbe ◽  
Alejandro Terrazas Mata ◽  
Brianne Herrera ◽  
Martha E. Benavente Sanvicente ◽  
Arturo González González ◽  
...  

2020 ◽  
Vol 6 (27) ◽  
pp. eaba1219
Author(s):  
Brandi L. MacDonald ◽  
James C. Chatters ◽  
Eduard G. Reinhardt ◽  
Fred Devos ◽  
Sam Meacham ◽  
...  

Investigations in the now-submerged cave systems on the Yucatán Peninsula continue to yield evidence for human presence during the Pleistocene-Holocene transition. Skeletal remains are scattered throughout the caves of Quintana Roo, most representing individuals who died in situ. The reasons why they explored these underground environments have remained unclear. Here, we announce the discovery of the first subterranean ochre mine of Paleoindian age found in the Americas, offering compelling evidence for mining in three cave systems on the eastern Yucatán over a ~2000-year period between ~12 and 10 ka. The cave passages exhibit preserved evidence for ochre extraction pits, speleothem digging tools, shattered and piled flowstone debris, cairn navigational markers, and hearths yielding charcoal from highly resinous wood species. The sophistication and extent of the activities demonstrate a readiness to venture into the dark zones of the caves to prospect and collect what was evidently a highly valued mineral resource.


2021 ◽  
Vol 45 (2) ◽  
pp. 241-250
Author(s):  
Ciprian Bîrsan ◽  
Constantin Mardari ◽  
Ovidiu Copoţ ◽  
Cătălin Tănase

Clathrus archeri is a saprophytic fungus native to the southern hemisphere which was introduced in Europe in the early twentieth century. Although it is naturalized in most regions of Central Europe, in Romania it is considered rather a rare species because it has been identified in only a few localities. Because of the rapid expansion of its range throughout Europe some authors assign this species an invasive potential. The objective of the paper was to identify both the potential distribution area and the potential suitable habitats for expansion in Romania and to highlight the environmental variables driving the probability of its occurrence. The maximum entropy model approach implemented in Maxent was used to model the species? potential distribution. The results highlighted altitude, snow cover length, the mean temperature of the driest quarter, and precipitation in the coldest quarter as the most important predictors of species? potential distribution in Romania. The map of the predicted distribution showed that the highest probability of occurrence for this species is in the mountainous and adjacent areas, while the map of habitat suitability confirmed that the best environmental conditions are in the Carpathians, while the most unfavourable are in the south-eastern regions of the country.


Sign in / Sign up

Export Citation Format

Share Document