Synonym with Leptodactylus typhonius by Boulenger, , Cat. Batr. Sal. Coll. Brit. In the Leptodactylus fuscus group of Heyer, , Sci. Bull. Nat. Hist. Mus . A very common and widely distributed South American frog Leptodactylus fuscus is known by several common names including the rufous frog, fuscous foam. Diet of Leptodactylus fuscus (Amphibia: Anura: Leptodactylidae) in the Pantanal of Miranda river, Brazil. Sugai, J.L.M.M. et al. Biota Neotrop.
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The aim of this study was to characterize, for the central region of the State of Rio Grande do Sul, Brazil, the reproductive biology of Leptodactylus fuscus Schneider,based on the analysis of gonadal development of males and females, reproductive leptoactylus, size-fecundity relationships, and occurrence of sexual dimorphism in body size.
Mature individuals were found from October to February and from October to December ffuscus The highest input of juveniles in the population was recorded in March There was a positive and significant correlation between the number of mature individuals and the mean monthly temperature. The population did not present sexual dimorphism in size. Males presented significant correlation only between snout-vent length and testes length.
All females had oocytes at four different maturation stages and there were no significant correlations regarding size-fecundity variables. The correlation between lepptodactylus size factor and females snout-vent length was not significant either.
The main difference between leptovactylus population and those that inhabit tropical climate was that temperature was responsible for stimulating the reproduction activity, instead of rainfall.
Amphibians, reproduction, subtropical climate. Amphibian reproductive cycles are under hormonal control, which responds to environmental variation.
Anurans from tropical regions tend to present continuous reproductive cycles; however, they reproduce in the season during which rainfall is sufficient to provide oviposition sites.
Leptodactylus Fitzinger, is divided into five large species groups, including the L. In this group reproduction generally occurs during rainy periods with high temperature. Males dig subterranean nests close to water bodies and attract females to enter, where oviposition occurs. Eggs are deposited in foam produced by the pair and tadpoles develop up to a certain stage inside the nest, which is destroyed by flooding or leptodadtylus when rains start, thus releasing the larvae to complete their development in the water HEYER, After that, strong genetic differentiation was observed within L.
In Brazil, many studies were carried out on L. Recently, a revision on L. Leptodxctylus the subtropical region, males of L. Fuscuz though the reproductive biology of L. Thus, the aim of this study is to characterize the reproductive biology of Leptodactylus fuscus based on the analysis of gonadal development of males and females, reproductive effort, size-fecundity correlation and existence of sexual dimorphism in body size, at a locality in the central region of Rio Grande do Sul State, Brazil.
There are natural fields near the study area. The mean annual fuscuw oscillates from Rainfall is regular throughout the year with annual rainfall index from mm to mm. Three lines of ten containers were installed: The traps remained open during all study, from October to Apriland were inspected three times a leptodactjlus. The leptodactyluw length was measured using a stereomicroscope with ocular scale and mass using a precision scale with resolution 0.
In order to assess maturity, monthly samples of testes were prepared for histological sections survey. Males with spermatozoa in the seminiferous tubules were considered mature. Males with SVL larger than the smallest mature male were considered mature.
Leptodactyllus histology observations, the pigmentation of vocal sacs was also checked to evaluate male maturity. Analyses were based on the left testis. The following size-fecundity correlations were investigated for mature individuals: SVL x testes length; 2. SVL x testes mass; 3. Those with darker yellow coloration and pronounced larger size were considered post-vitellogenic mature.
Mature oocytes of both ovaries were counted and the diameter of the ten largest ones was measured for each female. Size-fecundity correlations were evaluated among the following variables: Females SVL x ovarian complement; 2. SVL x mass of mature ovaries; 3. Body mass x ovarian complement; 4. Body mass x mass of mature ovaries.
For males, the value recorded for the left testis was multiplied by two. The Spearman r s Correlation Coefficient was used to calculate correlation between size and fecundity, OSF and female SVL, and temperature and rainfall and abundance of mature individuals.
Normality was evaluated with the Shapiro-Wilk test. Monthly mean temperature was higher in January and lower in June and July. The monthly rainfall varied along the year, with the most rainy months at the end of Leptodacyylus. Among the testes analyzed by histological sections, fkscus Of these, 13 had vocal sacs pigmented and five leptodacgylus not.
In addition, 11 individuals had larger SVL than the smallest mature male. Eight of them had vocal sacs pigmented and three had not.
Twelve mature females of L. The number of juveniles in the population greatly increased in March The smallest juvenile caught in that month had During the first three months of the year Jan – Mar juveniles of different sizes were found.
The studied population of L. Analysis of gonads of the present study population indicated that reproduction occurred from October to March. All previous studies with L. In our study, the capture of mature individuals showed positive correlation only with monthly temperature.
The number of vocalizing males for the whole anuran community also showed leptoxactylus with monthly temperature in a previous study conducted in this same area SANTOS leptodactyluw al. In south Brazil, characterized by a subtropical climate, temperature presents high variation along the year, while rainfall is observed well distributed round-year with no dry season.
Thus, the reproductive behavior variation of L. Besides, the population studied here reacted to a different climate factor from those of the same genetic lineage, but that leptodactylu tropical environment CAMARGO et al.
The population of L. The highest recruitment of juveniles of L. In Venezuela, SOLANO observed that, in the laboratory, the metamorphosis of this species takes 50 days and the size of the newly metamorphosed individuals is around 11 to 12 mm, reaching 20 mm after only two months. If we do not consider population or climate differences, the observation of juveniles of 20 mm or larger in January in the present fuacus suggests that clutches were laid in Octoberwhich corroborates the findings from gonad analysis that the reproductive activity begins in October.
The large number of juveniles captured at the end of fuscuss reproductive period is probably related to their displacements searching for shelter to undergo colder months, since the species was not fuscis in the winter June to August. This increase was recorded for L. In the present study, some males with mature tests had not pigmented vocal sacs.
The development of this secondary characteristic may have been retarded in these individuals. On the other hand, fsucus males with pigmented vocal sacs had no mature testes. Only the left testis was evaluated here and it is possible that these individuals had spermatozoids on the right test.
Therefore, these results highlight the importance of carrying out histological analysis of at least one testis leptoodactylus assess male maturity. Males of a population of L. Otherwise, these populations may be considered very similar. They did not evaluate individuals from Pantanal and Rio Grade do Sul, but it leptoxactylus possible that these two populations belong to the same group.
Their record for L. The low reproductive effort found in both studies is probably related to the reproductive strategy used by the species, in which the male builds a subterranean nest, attracts a female and the clutch is laid there, which may prevent eliminates sperm competition. In comparison to this study, in Mato Grosso do Sul, females of L. The population studied here presented most of the body filled by the gonads, which were heavier probably because the post-vitellogenic oocytes were smaller but occurred in greater number.
In Roraima, post-vitellogenic oocytes had similar size of that recorded herein, but found in a smaller number. In Venezuela SOLANO,female reproductive effort was higher than in this study, probably due to larger oocytes found in a great number, once the body size was similar.
The trend to decrease egg number with the increase in fuecus diameter was suggested to be related to more terrestrial reproductive modes HEYER, Comparing to other studies, the population herein is the one that least represents this trend, but the values found are in accordance to what HEYER proposed for the L. Fusccus to CRUMPthe ovary size factor increases together with the increase of the female SVL in each reproductive mode, but this correlation was not verified in this study. Neither was it recorded by SOLANOwhich suggests a hypothesis of influence of nutritional and environmental condition on the oocytes production.
The reproductive biology of L. The main difference concerns the factor responsible for stimulating the reproduction, which is rainfall in seasonally dry tropical regions whereas in the area of this study, where rainfall is well distributed along the year, temperature played this role.
Such data demonstrate the environmental plasticity of the species and evidence that populations of the same species may present different patterns according to the climate under which they live. We thank Janaine Melchiors for the orientation with reproductive biology, Lephodactylus P.
IUCN Red List of Threatened Species
Prado and the anonymous reviewers for the suggestions on the manuscript. Distinct architectures of subterranean nests in the genus Leptodactylus of the fuscus Group Anura, Leptodactylidae. Herpetological Review 37 1: Revista Brasileira leptodactylis Zoologia 21 4: An austral anuran assemblage in the Neotropics: Journal of Natural History Amphibians of an open Cerrado fragment in southeastern Brazil.