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1.
Zookeys ; 993: 121-155, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33262676

RESUMO

A new phylogeny for the Pristimantis lacrimosus species group is presented, its species content reviewed, and three new species described from the eastern slopes of the Ecuadorian Andes. Our phylogeny includes, for the first time, samples of P. aureolineatus, P. bromeliaceus, and P. lacrimosus. The morphology of hyperdistal subarticular tubercles is also assessed among 21 species of Pristimantis. The P. lacrimosus species group is composed of 36 species distributed in the Chocó, Guiana, and Amazon regions of tropical South America with a single species reaching Central America. Ancestral area reconstruction indicates that, despite its high diversity in the Amazon region, the P. lacrimosus group originated in the Pacific basin, Chocó region of Ecuador and Colombia. Pristimantis amaguanae sp. nov. is most closely related to P. bromeliaceus. It differs from P. bromeliaceus by being smaller, having transversal dark bands in the hindlimbs (absent or faint in P. bromeliaceus) and the absence of discoidal fold (present in P. bromeliaceus). Pristimantis nankints sp. nov. and P. romeroae sp. nov. are part of a clade of predominantly light-green frogs that includes P. acuminatus, P. enigmaticus, P. limoncochensis, and P. omeviridis. Pristimantis nankints sp. nov. and P. romeroae sp. nov. can be distinguished from all of them by the presence of a dark dorsolateral stripe that borders a light green band on a green background. Hyperdistal tubercles are present in all examined species of the P. lacrimosus species group and its sister clade. Species with hyperdistal tubercles are characterized by having relatively long terminal phalanges and narrow T-shaped expansion at the end of the terminal phalange. We discuss the phylogenetic distribution of these characters and their potential diagnostic significance.

2.
Zookeys ; (593): 139-62, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27408555

RESUMO

We describe two new species of frogs of the genus Pristimantis from the eastern slopes of the Ecuadorian Andes, at Parque Nacional Llanganates. The new species are characterized by the spiny appearance typical of several species inhabiting montane forests. Pristimantis yanezi sp. n. is most similar to Pristimantis colonensis and Pristimantis incanus but differs from both in groin coloration and by having smaller tubercles on the upper eyelids, heels, and tarsus. Pristimantis llanganati sp. n. is most similar to Pristimantis eriphus and Pristimantis chloronotus. It can be distinguished from Pristimantis eriphus by the color pattern on the scapular region and by having smaller conical tubercles on the dorsum. Pristimantis chloronotus differs from Pristimantis llanganati sp. n. in having a pair of sinuous paravertebral folds. Both new species occur in a region with few amphibian collections and nothing is known about their abundance and ecology. Therefore, it is recommended to assign them to the Data Deficient Red List category. Updated figures of species richness of Pristimantis among biogeographic regions in Ecuador are also presented. Pristimantis reach their highest diversity in Montane Forests of the eastern versant of the Andes. Its species richness across regions cannot be explained by regional area, elevation, temperature, or precipitation. Political endemism in Pristimantis is higher than that of other terrestrial vertebrates.

3.
PLoS One ; 8(11): e80934, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24260515

RESUMO

Dimorphic cleistogamy is a specialized form of mixed mating system where a single plant produces both open, potentially outcrossed chasmogamous (CH) and closed, obligately self-pollinated cleistogamous (CL) flowers. Typically, CH flowers and seeds are bigger and energetically more costly than those of CL. Although the effects of inbreeding and floral dimorphism are critical to understanding the evolution and maintenance of cleistogamy, these effects have been repeatedly confounded. In an attempt to separate these effects, we compared the performance of progeny derived from the two floral morphs while controlling for the source of pollen. That is, flower type and pollen source effects were assessed by comparing the performance of progeny derived from selfed CH vs. CL and outcrossed CH vs. selfed CH flowers, respectively. The experiment was carried out with the herb Ruellia nudiflora under two contrasting light environments. Outcrossed progeny generally performed better than selfed progeny. However, inbreeding depression ranges from low (1%) to moderate (36%), with the greatest value detected under shaded conditions when cumulative fitness was used. Although flower type generally had less of an effect on progeny performance than pollen source did, the progeny derived from selfed CH flowers largely outperformed the progeny from CL flowers, but only under shaded conditions and when cumulative fitness was taken into account. On the other hand, the source of pollen and flower type influenced seed predation, with selfed CH progeny the most heavily attacked by predators. Therefore, the effects of pollen source and flower type are environment-dependant and seed predators may increase the genetic differences between progeny derived from CH and CL flowers. Inbreeding depression alone cannot account for the maintenance of a mixed mating system in R. nudiflora and other unidentified mechanisms must thus be involved.


Assuntos
Acanthaceae/fisiologia , Flores/fisiologia , Aptidão Genética/fisiologia , Polinização/fisiologia , Autofertilização/fisiologia , Acanthaceae/parasitologia , Animais , Evolução Biológica , Meio Ambiente , Comportamento Alimentar/fisiologia , Flores/anatomia & histologia , Flores/parasitologia , Endogamia , Luz , México , Mariposas/fisiologia , Pólen/fisiologia , Comportamento Predatório/fisiologia , Reprodução , Sementes/parasitologia
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