A new species of terrestrially-nesting fanged frog (Anura: Dicroglossidae) from Sulawesi Island, Indonesia

Herein, we describe a new species of terrestrially-nesting fanged frog from Sulawesi Island, Indonesia. Though male nest attendance and terrestrial egg deposition is known in one other Sulawesi fanged frog (Limnonectes arathooni), the new species exhibits a derived reproductive mode unique to the Sulawesi assemblage; male frogs guard one or more clutches of eggs festooned to leaves or mossy boulders one to two meters above small slow-moving streams, trickles, or seeps. This island endemic has thus far been collected at three sites on Sulawesi: one in the Central Core of the island, and two on the Southwest Peninsula-south of the Tempe Depression (a major biogeographical boundary). The new Limnonectes has the smallest adult body size among its Sulawesi congeners-with a maximum snout-vent length of about 30 millimeters. Beyond its unique reproductive behavior and body size, the species is further diagnosed on the basis of advertisement call and genetic distance from sympatric fanged frogs. The discovery and description of the new species highlights the remarkable reproductive trait diversity that characterizes the Sulawesi fanged frog assemblage despite that most species in this radiation have yet to be formally described.

Visual communication and aggressive behaviour in a giant mute torrent-frog, Megaelosia apuana (Anura; Hylodidae)

Advertisement call is the most common signal used by anurans for intraspecific communication. However, some species have lost the ability to emit these vocalizations and are denoted as mute. Alternatively, these species may communicate by visual, tactile and chemical signals. The lack of advertisement call could be explained by the high background noise of breeding microhabitats. A model group to study alternative communication tactics is the genus Megaelosia, which is composed by seven mute species that inhabit noisy streams, and for which no information on intraspecific communication is available. We monitored a population of M. apuana and described its visual signalling during aggressive interactions between males. This interaction included visual signalling, physical combat, and the retreat of the smaller individual. No audible sound was detected during the whole aggressive interaction, reinforcing the genus muteness. This is the first report of any communication behaviour for the genus Megaelosia.

Phylogenetic relationships of the mustache toads inferred from mtDNA sequences

Species of the genus Vibrissaphora are unique among all anurans in that males exhibit external cornified spines in the maxillary region during the breeding season. They were separated from species of the genus Leptobrachium based on this unique character. We construct a phylogeny using the 16S, ND4, and cytochrome b mitochondrial genes of 42 individuals from eight species of Vibrissaphora and five species of Leptobrachium from mainland China, Southeast Asia, and Hainan Island. Species of both Oreolalax and Scutiger were used as outgroups. The results indicate that: L. huashen and L. chapaense form a clade that is nested within Vibrissaphora, and L. hainanense is the sister taxon to the clade comprising all Vibrissaphora plus L. chapaense and L. huashen; V. boringiae is grouped with a clade consisting of V. leishanensis, V. liui, and V. yaoshanensis; and V. yaoshanensis is a species separate from V. liui. We propose taxonomic changes that reflect these findings. Also based on the resulting phylogenetic trees, we propose that the mustache toads originated in the trans-Himalayan region of southwest China, and that the evolution of maxillary spines, large body size, and reverse sexual size dimorphism in these frogs was influenced by intrasexual selection due to adopting a resource-defense polygyny mating system.

Vertebrate Secondary Sexual Characteristics-Physiological Mechanisms and Evolutionary Patterns

As most commonly presented, the organization-activation theory of sexual differentiation emphasizes the importance of the relative age of the organism for understanding steroid hormone effects. However, considering the actual physiological mechanisms of tissue enlargement (hyperplasia/hypertrophy) provides an additional perspective for interpreting patterns of evolutionary change in sexual dimorphism. Using that focus, it is possible to suggest mechanistic explanations for patterns of allometry and the size of some secondary sexual characteristics produced by "runaway" selection. It can also lead to the formulation of testable hypotheses regarding the type of sexually dimorphic characters that might evolve through "good genes" models; the relationship between intrasexual competition, polygyny, and the development and size of male weapons; and the control and type of secondary sexual characteristics that will be present in males with associated and disassociated reproductive patterns.