Cytochemistry and polarization microscopy of amphibian sperm cell nuclei presumed to differ in basic protein composition

The pattern of availability of free DNA phosphates, and the kind of DNA-protein complex arrangement, both induced by nuclear basic proteins, and the richness in arginine residues in these proteins were investigated cytochemically and cytophysically in spermatozoa of the South-American Hylidae species, Hyla fuscovaria and Hyla biobeba. The aim was to demonstrate differences at the level of sperm histones in two species of Hyla until recently considered to be congeneric. The results indicated differences in the spermatozoal nuclear basic proteins and DNA-protein complexes when the two species were compared. The spermatozoa of Hyla biobeba were assumed to be likely to contain a Bloch's ''type 3'' protein type (intermediate sperm basic protein), similarly to Hyla species of North and Central America. on the other hand, the data obtained for the spermatozoa of Hyla fuscovaria indicated that they contain a protamine or protamine-like protein, differing from Hyla biobeba and Hyla species of North and Central America. It is suggested that the differences reported here may be genus-specific, since Hyla fuscovaria has recently been reclassified as Scinax fuscovaria based on parameters other than sperm histone types. These findings are in agreement with the general view of a wide variability in sperm nuclear proteins in the Anura group.

Intrageneric karyotypic divergence in Scythrophrys and new insights into the relationship with Paratelmatobius (Anura, Leptodactylidae)

Three populations of Scythrophrys from Brazil were studied cytogenetically. The karyotype found in Piraquara (Parana State) and Sao Bento do Sul (Santa Catarina State) (karyotype 1) differed from that of Rancho Queimado (Santa Catarina State) (karyotype 11) in NOR location and in the occurrence of some C-bands. In karyotype I, pair 5 contained NOR-bearing chromosomes, while in karyotype 11 the NOR occurred in pair 10. This difference probably accounts for the inverted classification of pairs 5 and 6 in these karyotypes, which appear to be homologous, as suggested by the presence of heterochromatic markers. These karyotypes also differed in the size of the non-centromeric C-bands in pairs 1 and 8. Comparison of the Scythrophrys karyotypes with those of the related genus Paratelmatobius revealed several similarities, especially between karyotype 11 of Scythrophrys and that of P. poecilogaster. Both karyotypes had a NOR in pair 10, so it was inferred to be present also in the common ancestor for these genera. The non-centromeric C-bands in pairs 7, 10, and in pair 5 of karyotype I and pair 6 of karyotype II of Scythrophrys are characters exclusively found in this genus.

Short-term movement and retreat sites of Leptodactylus labyrinthicus (Anura : Leptodactylidae) during the breeding season: A spool-and-line tracking study

Capture/recapture studies significantly increase our knowledge of the natural history of anuran amphibians. Many different methods have been employed in these studies, but a number of new techniques still require experimental validation. During two reproductive seasons in a Cerrado remnant in southeastern Brazil, we investigated the movement patterns and habitat use of the pepper frog, Leptodactylus labyrinthicus, using a spool-and-line device. This low-cost device did not appear to interfere with the activities of the frogs and allowed for constant monitoring, showing precise routes of movement and great predictability of relocations. Both sexes were active at night. During the day, males and females made use of retreat sites under vegetation or in burrows constructed by small- and medium-sized mammals. Males and females did not use standardized routes; there were no significant differences between their movements, and movements were not correlated with body size or environmental conditions. Individuals are able to move further than 100 m per day, a characteristic that may enable this species to colonize or recolonize open areas.

RESPONSE TO TEMPERATURE IN THE OXYGEN-UPTAKE OF AWAKE AND DORMANT FROGS (AMPHIBIA, LEPTODACTYLIDAE)

In southeastern Brazil the leptodactylid frogs Leptodactylus fuscus and Physalaemus fuscomaculatus enter dormancy during the dry season. Oxygen uptake was measured in awake and dormant groups of both species in a temperature range at which these frogs are usually exposed throughout the year. Oxygen uptake was lower for dormant groups at high temperature, and a lack of response to temperature was reported between 20 - 25 C in the dormant group of both species. This temperature-intensitive range can be considered an adaptive feature to save fat reserves during dormancy.

Visual and acoustic communication in the Brazilian torrent frog, Hylodes asper (Anura : Leptodactylidae)

We studied the signaling, territorial, and courtship behaviors of the diurnal frog Hylodes asper. Visual and acoustic communication were used during intraspecific interactions involving males, females. and subadults. Hylodes aspcr has a complex visual communication system, of which foot-flagging is the most distinctive display observed in the repertoire of visual signals. The splash zone produced by the waterfalls and torrents creates a high, nearly constant, humidity near the streams, reducing the risk of desiccation which enables the diurnal activity of H. asper. Although the ambient sound pressure levels (SPL), measured at the calling sites, are similar to the SPL of the advertisement calls, the high-pitched calls of H, asper, are spectrally different from the noise produced by the water current. Thus. The ambient noise produced by the water current may not interfere significantly with the acoustic communication of this species. The noise and the nearly constant and high humidity produced by the torrents and waterfalls, along with the availability of Light, probably favored the evolution of contrasting colors and visual communication in H. asper: Males of H, aspcr excavate underwater chambers that are probably used to shelter the eggs and to prevent the clutch from being drifted downstream.

A REVIEW OF THE GENUS MEGAELOSIA (ANURA, LEPTODACTYLIDAE) WITH A DESCRIPTION OF A NEW SPECIES

A new species of Megaelosia is described from the Atlantic Forest in the northern part of São Paulo, southeastern Brazil. Based on examination of topotypic specimens of Megaelosia massarti, this species is removed from the synonymy of M. goeldii. Tadpoles of M. lutzae and M. massarti are described and natural history observations of M. massarti and M. goeldii are reported. Diagnoses, measurements, figures, distributional data, and a key for the species of Megaelosia are provided.

A new island species of Scinax (Anura; Hylidae) from southeastern Brazil

A new species of hylid frog, from the genus Scinax, is described from Ilha de Porcos Pequena at the southern coast of São Paulo State, southeastern Brazil. The new species belongs to the Scinax perpusillus species group and is diagnosed by the following set of characters: moderate-size (males 16.2-18.8 turn SVL, female 18.8-20.6 mm SVL); canthus rostralis distinct and well defined; V-shaped depression between nostrils; eyes protruding and prominent, glandular skin surface of legs. This new species is found only on Ilha de Porcos Pequena, an island of approximately 24 ha and, therefore, is threatened because of restricted range size and susceptibility to habitat modification.

Morphological variation in two genetically distinct groups of the golden-striped salamander, Chioglossa lusitanica (Amphibia : Urodela)

Morphometric and colour pattern variation in the endemic Iberian salamander Chioglosso lusitanica is concordant with the genetic differentiation of two groups of populations separated by the Mondego river ill Portugal. Salamanders from the south have shorter digits than those from the north. Clinal variation with a south to north increase in limb. toe and finger length was found superiniposed on this dichotomy resulting in stepped clines for characters describing appendage size. Genetic variability was paralleled by colour pattern variability in the contact zone and in northern populations. To explain the observed parallels we invoke the neutral processes of vicariant isolation. admixture in a secondary contact zone, genetic drift in addition to selection acting along all environmental gradient. Morphological constraints imposed by a highly specialized ecological niche may explain why the genetic subdivision of C. lusitanica since the early, Pleistocene has remained fairly cryptic.

A New Species of Proceratophrys (Anura: Cycloramphidae) from Midwestern Brazil

We describe adult morphology, advertisement call, and natural history aspects of a new frog species from riparian habitats alongside intermittent headwater streams in southwestern Cerrado, the second largest biome in Brazil. Presently known from three localities in Mato Grosso State, the new species belongs to the Proceratophrys cristiceps group. It is characterized mainly by small size (adult snout vent length approximately 46 mm), snout rounded in dorsal view and obtuse in lateral view, absence of flared lips, dorsal skin granular, and absence of both postocular swellings and prominent palpebral appendages. The advertisement call of the new species consists of a single note with 19-25 pulses. Calls are repeated at mean intervals of 0.7 sec. Mean dominant frequency is 1,250.2 Hz, with ascendant modulation.

Chromosomal differentiation of Hyla nana and Hyla sanborni (Anura, Hylidae) with a description of NOR polymorphism in H-nana

Specimens of Hyla nana and Hyla sanborni from a syntopic population were studied cytogenetically. These species are morphologically very similar and are frequently misidentified, confused with each other. Both species had a diploid chromosome number, 2n = 30. However, the karyotypes of H. nana and H. sanborni differed considerably from each other in the number of submetacentric and telocentric chromosomes. The two species also differed in their primary NOR-bearing chromosomes (metacentric pair 13 in H. nana and telocentric pair 12 in H. sanborni). Additional nucleolus organizer regions (NORs) were detected by Ag-NOR staining and FISH in chromosome pairs 1, 5, 6, 12, and 14 in seven specimens of H. nana. Thus, a total of six patterns of NOR were identified. These differences in karyotype and in NOR location allowed the unambiguous identification of syntopic individuals of the two species. However, the chromosomal morphology of both species differed from that reported for populations from other geographic regions, suggesting that a systematic reevaluation of this group of Hyla may be necessary.

Natural History of the Lutz's Frog Cycloramphus lutzorum Heyer, 1983 (Anura: Cycloramphidae) in the Brazilian Atlantic Forest: Description of the Advertisement Call, Tadpole, and Karyotype

We describe the advertisement call, tadpole, karyotype, and additional information on the natural history of Cycloramphus lutzorum from southern Brazil. Sonograms were generated from digitally recorded calls. Tadpoles were collected in the field for description in the lab, and an adult was collected for karyotyping. Data on seasonal activity were gathered monthly from November 2005 to November 2007. All tadpoles (N = 21), juveniles (N = 18), and adults (N = 52) were found exclusively in streams. Reproduction, as identified by calling frogs, occurred from July through November. Frogs call all day long, but mostly at dusk, from rock crevices inside the stream edges near the splash zone. The call is short and loud, with 11 pulsed notes, of 491-641 ms, with a dominant frequency of 0.98-1.39 kHz. We describe the exotrophic and semiterrestrial tadpoles, always found in constantly humid vertical rock walls in the stream. Tadpoles of C. lutzorum are recognized by differences in labial tooth row formula, eye diameter, body shape, position of nares, and development of tail. Like congeneric species, the karyotype of C. lutzorum comprises 26 metacentric and submetacentric chromosomes. Cycloramphus lutzorum is restricted to and adapted for living in fast flowing streams, many of which are threatened by deforestation, pollution, and habitat loss. Therefore, we recommend the status of C. lutzorum be changed from its current "Data Deficient" to "Near Threatened (NT)" in the IUCN species red list.

The advertisement call of Dendropsophus nahdereri (Anura, Hylidae, Dendropsophini).

The Dendropsophus marmoratus group is composed of eight species known for their explosive breeding habits and morphologically characterized by a bark-like dorsum, warty skin around the lower lips and an extremely large vocal sac. Within this group, D. nahdereri is the only species with distribution restricted to the southern region of Brazil. Apart from the original description and its tadpole, nothing else is known about this species. Using a mechanistic definition of note, we describe the advertisement call of D. nahdereri, which is similar to the advertisement calls of other species of the group and frequently has "final pulseclusters" as defined in the text.