Some conditions from complete dissection of hand and foot muscles of Pristimantis bogotensis (Strabomantidae) presented here have not been reported in anurans. One muscle not described before was found: the m. abductor ulnocarpalis. Muscles of the forearm, the hand, and the foot were found as exclusive characters in this species. Two minor variants (sensu Raikow et al., 1990) were identified, showing that it is important to examine hind and forelimbs of both sides of the body (left and right) in anatomical studies for detecting intraspecific variation.

Hoyos, J.M. and Salgar, L. 2016. New conditions and intraspecific variation of some muscles of hands and feet of Dendropsophus labialis (Peters, 1863) (Anura, Hylidae). -Acta Zoologica (Stockholm) 97: 143-153.Systematics of frogs have been based on osteological and molecular characters; however, the morphology of the muscles of hands and feet has proven to be an important complement to these studies, but it has not been sufficiently studied. This study presents undescribed conditions based on the origin, insertion or arrangement of 18 muscles of hands and feet of Dendropsophus labialis, and intraspecific variation. Muscles of four specimens (two males and two females) were examined to observe both sides of each specimen determining new conditions, and comparing them with documented species of Dendropsophus. Four intraspecific variant categories were established: Minor, unique, explosive and mimicking. Mainly mimicking, explosive and unique variations were found. Our results show the need to expand intraspecific studies in more species of Dendropsophus and to assess its value in the phylogeny of the genus. The family Hylidae may be identifiable based upon the combination of character states of some of these muscles: the m. flexor indicis superficialis proprius and the group of tendines superficialis digitorum of hands and foot, the m. extensor brevis superficialis Digiti III of the hand, the m. extensor brevis superficialis Digiti IV in hands and the mm. extensores breves profundi Digiti III in hands.

We present a phylogenetic analysis within the Pristimantis unistrigatus group (Anura, Craugastoridae) of Colombia. Characters from the superficial muscles of the hands and feet as well as external characters were taken for analysis. Most of the muscle characters were observed directly, and some were taken from the literature. Similarly, the external ones were taken mostly from the original descriptions and others from the literature as well. Two matrices were constructed, as the species belonging to this group have changed in recent years with respect to the initially proposed when the group was defined. The results lead us to conclude that the group is not monophyletic, although there are some relationships that are worth to survey because they are kept in the very last cladograms obtained for both proposals. It is suggested that these last relationships should be explored in particular, and the overall group in general, increasing the number of characters and taxa that belong to P.unistrigatus. An open question we left is whether actually is worth to keep these informal taxonomic hierarchy called group within the genera of anurans.

SUMMARY:Transparency technique to demonstrate cartilage and skeleton has been used from years 70. This consists basically of the muscle digestion through an enzyme (trypsine), and the staining of cartilage and skeleton using alcian blue and alizarin red on specimens previously fixed to formalin. This technique can be used to study the state of the cartilage and the bones in different stages of the development and to observe abnormalitys. Also it can be used to demonstrate museum specimen skeleton preserved in liquid. In this article is showed the application of this technique for the first time in rodents and adult bats, besides some annotations to optimize the procedure.

Current climate change is generating accelerated increase in extreme heat events and organismal plastic adjustments in upper thermal tolerances, (critical thermal maximum ‐CTmax) are recognized as the quicker mitigating mechanisms. However, current research casts doubt on the actual mitigating role of thermal acclimation to face heat impacts, due to its low magnitude and weak environmental signal. Here, we examined these drawbacks by first estimating maximum extent of thermal acclimation by examining known sources of variation affecting CTmax expression, such as daily thermal fluctuation and heating rates. Second, we examined whether the magnitude and pattern of CTmax plasticity is dependent of the thermal environment by comparing the acclimation responses of six species of tropical amphibian tadpoles inhabiting thermally contrasting open and shade habitats and, finally, estimating their warming tolerances (WT = CTmax – maximum temperatures) as estimator of heating risk. We found that plastic CTmax responses are improved in tadpoles exposed to fluctuating daily regimens. Slow heating rates implying longer duration assays determined a contrasting pattern in CTmax plastic expression, depending on species environment. Shade habitat species suffer a decline in CTmax whereas open habitat tadpoles greatly increase it, suggesting an adaptive differential ability of hot exposed species to quick hardening adjustments. Open habitat tadpoles although overall acclimate more than shade habitat species, cannot capitalize this beneficial increase in CTmax, because the maximum ambient temperatures are very close to their critical limits, and this increase may not be large enough to reduce acute heat stress under the ongoing global warming.