TL;DR: A unique chytrid fungus is isolated and characterized, Batrachochytrium salamandrivorans sp.
Abstract: The current biodiversity crisis encompasses a sixth mass extinction event affecting the entire class of amphibians. The infectious disease chytridiomycosis is considered one of the major drivers of global amphibian population decline and extinction and is thought to be caused by a single species of aquatic fungus, Batrachochytrium dendrobatidis. However, several amphibian population declines remain unexplained, among them a steep decrease in fire salamander populations (Salamandra salamandra) that has brought this species to the edge of local extinction. Here we isolated and characterized a unique chytrid fungus, Batrachochytrium salamandrivorans sp. nov., from this salamander population. This chytrid causes erosive skin disease and rapid mortality in experimentally infected fire salamanders and was present in skin lesions of salamanders found dead during the decline event. Together with the closely related B. dendrobatidis, this taxon forms a well-supported chytridiomycete clade, adapted to vertebrate hosts and highly pathogenic to amphibians. However, the lower thermal growth preference of B. salamandrivorans, compared with B. dendrobatidis, and resistance of midwife toads (Alytes obstetricans) to experimental infection with B. salamandrivorans suggest differential niche occupation of the two chytrid fungi.
TL;DR: Comparisons with animal data are presented, and the results show striking similarities with the gaits observed with real salamanders, in particular concerning the timing of the body’s and limbs’ movements and the relative speed of locomotion.
Abstract: In this paper, we present Salamandra robotica II: an amphibious salamander robot that is able to walk and swim. The robot has four legs and an actuated spine that allow it to perform anguilliform swimming in water and walking on the ground. The paper first presents the new robot hardware design, which is an improved version of Salamandra robotica I. We then address several questions related to body–limb coordination in robots and animals that have a sprawling posture like salamanders and lizards, as opposed to the erect posture of mammals (e.g., in cats and dogs). In particular, we investigate how the speed of locomotion and curvature of turning motions depend on various gait parameters such as the body–limb coordination, the type of body undulation (offset, amplitude, and phase lag of body oscillations), and the frequency. Comparisons with animal data are presented, and our results show striking similarities with the gaits observed with real salamanders, in particular concerning the timing of the body’s and limbs’ movements and the relative speed of locomotion.
TL;DR: Tests using four-taxon subsamples suggest that these lineages diverged nearly simultaneously in the Late Miocene, approximately 6 to 8 million years ago, when extensive uplifting of Anatolia occurred in response to the Arabian collision.
TL;DR: Following unilateral iontophoretic application of HRP into the optic tectum of Salamandra salamandra, retrogradely HRP-filled cells were found bilaterally in the pretectum, tegmentum isthmi, the reticular formation, pars medialis, and in the nucleus vestibularis magnocellularis.
Abstract: Following unilateral iontophoretic application of HRP into the optic tectum of Salamandra salamandra, retrogradely HRP-filled cells were found bilaterally in the pretectum, tegmentum isthmi, the reticular formation, pars medialis, and in the nucleus vestibularis magnocellularis. The area octavo-lateralis projects only to the caudal part of the tectum. Ipsilateral projections were noted from the dorsal gray columns of the cervical spinal cord, the dorsal tegmentum, the thalamus dorsalis pars medialis, thalamus dorsalis, pars anterior (to the rostral one-third of the tectum), the thalamus ventralis (in its entire rostro-caudal extent), and the preoptico-hypothalamic complex. Retrogradely filled cells were identified in deeper layers of the contralateral tectum. There are two telencephalic nuclei projecting ipsilaterally to the tectum via the lateral forebrain: the ventral part of the lateral pallium, and the posterior strio-amygdalar complex.
TL;DR: According to measures of larval abundances in 1999 and 2003 the population of S. salamandra has suffered a marked decline but no significant trend was observed for B. bufo, and the analysis of the skin of post-metamorphic specimens revealed the presence of chytrid sporangia and discharge tubes in both species.
Abstract: Chytridiomycosis is a fatal disease associated with amphibian population declines and extinctions worldwide. In a protected area in central Spain, the Penalara Natural Park, the disease almost extirpated the population of Alytes obstetricans over only a few years, but did not apparently affect other amphibians. We present new observations documenting the occur- rence of the disease in other species. In 2001-2003 we collected over 400 larvae or recently metamorphosed individuals of Salamandra salamandra and also several dead individuals of Bufo bufo. The analysis of the skin of post-metamorphic specimens revealed the presence of chytrid sporangia and discharge tubes in both species. According to measures of larval abundances in 1999 and 2003 the population of S. salamandra has suffered a marked decline but no significant trend was observed for B. bufo. We discuss the possible role of chytridiomycosis in the decline of S. salamandra and comment on the differential susceptibility exhibited by various species in the amphibian community at Penalara.