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1.
2.
《Journal of Natural History》2012,46(21):2789-2801
We studied the age structure and the growth of a breeding population of parsley frogs, Pelodytes punctatus, from a pond system in northern Spain using skeletochronological methods. This population lives in an upland area with marked seasonal differences characterized by long, cold winters and dry summers. We assessed, using the mark–recapture method, the annual periodicity of bone growth marks. Only one line of arrested growth is laid down per winter, showing, in general, a well-defined histological structure. Females are larger than males with 43.31 and 36.32?mm average body length, respectively. This sexual dimorphism in body length increases with age. Males and females reach sexual maturity when they are 1 year old. The oldest males were 8 years old while the females were 2 years older. Growth curves for both sexes were constructed based on body size and the number of lines of arrested growth found in bone sections. The growth rate of males declined abruptly after the first year. Females delayed reproduction and continued to grow at a high rate for 2 years longer than males, thus reaching a higher asymptotic size.  相似文献   

3.
《Journal of Natural History》2012,46(29-32):1841-1851
Phyllomedusa azurea and P. sauvagii are treefrogs from seasonal dry environments of Central Brazil. We report on reproductive and other natural history features of these species. The study was carried out in Serra da Bodoquena, Mato Grosso do Sul, Brazil. The reproductive period was determined by the presence of vocalizing males, amplectant pair or presence of tadpoles. The reproductive effort was measured as the ratio of gonad mass in relation to body mass (BM). The reproduction of both species was correlated with the rainy season. Female P. sauvagii produced more eggs and their eggs were larger than those of P. azurea. Both species showed sexual dimorphism in relation to the snout–vent length (SVL) and BM. The mating behaviour of both species was similar. Males in both species showed similar reproductive efforts, but females of P. azurea invested more in gonads compared to the males of P. sauvagii. Phyllomedusa azurea showed a significant relation between SVL versus number of the mature eggs (NME), and P. sauvagii between SVL versus NME and BM versus ovarian mass.  相似文献   

4.
《Journal of Natural History》2012,46(35-36):2245-2256
Itapotihyla langsdorffii is a large “casque-headed” treefrog (Hylidae: Lophiohylini) found along most of the Brazilian Atlantic Forest biome. We studied some aspects of the ecology of a population of I. langsdorffii from the Estação Biológica de Santa Lúcia, in Espírito Santo State, southeastern Brazil. Itapotihyla langsdorffii shows considerable sexual size dimorphism, with females (mean snout-vent length 103 mm) being significantly larger than males (mean snout-vent length 81 mm). This species is an explosive breeder with a generalized reproductive mode and has a mean brood size of over 6000 eggs. It feeds on few, large prey, with orthopterans being the dominant items in the diet, though even smaller frogs may occasionally be preyed upon. We discuss our data, making comparisons with other Neotropical hylids, with emphasis on other species in the Tribe Lophiohylini.  相似文献   

5.
6.
《Journal of Natural History》2012,46(19-20):1287-1307
Larval ontogeny of the scarab Mecynorhina polyphemus was monitored throughout all instars, and larvae were weighed at 7-day intervals. Durations of the prepupal, pupal and postpupal stages were recorded. Larvae increase their body masses over 300 times during ontogeny. Male imagines are larger than females, and this is primarily a function of faster growth rates during instar III, resulting in significantly heavier larvae at the end of this instar. The durations of the three instars are not significantly different in males and females, but the duration of the prepupal and postpupal phases is significantly longer in males. There is a strong correlation in both sexes between maximal larval mass and the mass of the imago, but larval mass–imago mass scales with significantly different slopes in males and females. Male larvae must allocate increasingly more resources into production of cephalic horns with increments in larval mass, requiring differently proportioned pupal chambers.  相似文献   

7.
《Journal of Natural History》2012,46(39-40):2497-2507
Brachycephalus garbeanus is an aposematic toadlet, endemic to the Atlantic Forest in the mountains of the state of Rio de Janeiro, southeastern Brazil. Information regarding the ecology of species in this genus is scarce, with no information on most species, including B. garbeanus. We provide ecological information about B. garbeanus, in particular regarding microhabitat use, sexual dimorphism in body size, and feeding habits. Our study was conducted in a montane area of the Parque Estadual dos Três Picos, the largest State park in Rio de Janeiro. Most of the B. garbeanus in the study area were found on the forest floor leaf litter. Females were larger on average than males. Brachycephalus garbeanus consumed a wide array of prey, comprising exclusively invertebrates and predominantly arthropods. There were seasonal differences in the diet composition, but mites and ants were important in both wet and dry seasons.  相似文献   

8.
The Leptodactylus pentadactylus species group is comprised of medium to large species of Neotropical frogs. Leptodactylus knudseni, a member of this species group, has a wide distribution throughout the Amazon Basin. Herein we describe aspects of the reproductive biology of L. knudseni and provide notes about the ontogenetic variation of its tadpoles based on a population in a non-flooded forest near Manaus, Amazonian Brazil. Amplectant pairs of L. knudseni lay foam nests in excavated basins on the edge of temporary ponds located on clay soil and at least 50 m from a stream. The tadpole development happens initially in the foam nests with access to the pond after the rain flooding the basins. Studied clutches lacked trophic eggs and tadpoles did not produce foam. Ontogenetic variations in L. knudseni tadpoles are related to size, teeth formulae and body colour. The use of excavated basins for the deposition of foam nests has been reported in several species of the L. pentadactylus group. The absence of trophic eggs and production of foam by the tadpoles differ from other species of the L. pentadactylus group. The tadpole morphology is similar to that described for other species of the group.  相似文献   

9.
《Journal of Natural History》2012,46(27-28):1729-1741
We describe the spatial pattern of variation in body size and sexual size dimorphism in the giant spiny frog, Paa spinosa (David, 1875). The study also aims to identify potential factors responsible for geographic morphological variation in the frog. The results indicate that primary production, which positively correlates with precipitation and summer temperature in China, had an important effect on body size of P. spinosa, whereas Bergmann's rule was more efficient to explain the influence of average minimum temperature in January. The species was sexually dimorphic for body size and body shape: the body size, jaw length and forelimb length of males were significantly larger than those of females. Furthermore, the degree of sexual size dimorphism varied geographically, but the relationship between the geographic variation of sexual size dimorphism and the climate was complex. Specifically, absolute sexual size dimorphism was positively correlated with the increased ambient temperature and decreased precipitation.  相似文献   

10.
《Journal of Natural History》2012,46(35):3217-3226
Animal mating systems are moulded by ecological factors, mainly the temporal patterns of reproduction. We report the reproductive period, use of microhabitats, clutch and egg sizes, reproductive efforts, occurrence of sexual size dimorphism, and the relation between body size and fecundity in the gravid females of Trachycephalus venulosus and Scinax fuscovarius at Serra da Bodoquena, Central Brazil. The reproduction of both species was correlated with the rainy season. Females of T. venulosus produced more eggs and their eggs were larger than those of S. fuscovarius. The females of both species were larger and heavier than males. The reproductive effort was measured as the ratio of gonad mass in relation to body mass. Females of both species presented similar reproductive efforts, but males of S. fuscovarius invested more in gonads compared to males of T. venulosus. Trachycephalus venulosus presented significant correlation between snout–vent length versus number of mature eggs and body mass versus number of mature eggs and ovarian mass. Scinax fuscovarius showed significant correlation between body mass versus ovarian mass. Trachycephalus venulosus is an explosive breeder, whereas S. fuscovarius has prolonged reproduction. These species are able to adapt to several types of habitat, due to behavioural and physiological plasticity.  相似文献   

11.
《Journal of Natural History》2012,46(29-30):1823-1834
Territoriality is common among amphibians with a prolonged breeding season and can be expressed through the defence of territories with vocalizations and aggressive interactions. The present study aims to describe the territorial behaviour of male Phyllomedusa nordestina, test whether the physical characteristics of males influence the results of disputes, and describe the vocalizations of the species. The study was conducted at temporary and permanent ponds located in the Ecological Reserve Michelin, Igrapiúna, Bahia, Brazil. Male P. nordestina defended territories and showed aggressive behaviour, consisting of vocal disputes, chasing and physical fighting. Winners were not bigger, heavier, or in better condition than the losers. The victory may be associated with the vocalization activity. Three types of vocalizations were recorded: the advertisement call, composed of one or two multipulsed notes, and two types of territorial calls. We also report on male patrolling behaviour and habitat use.  相似文献   

12.
《Journal of Natural History》2012,46(3-4):229-240
We studied patterns of microhabitat use by adults of two sympatric Bokermannohyla species at the Reserva Particular do Patrimônio Natural Santuário do Caraça, southeastern Brazil. We selected three streams, one where both species occurred in syntopy and the other two where each one occurred alone. We sampled 150-m transects in each stream throughout 1 year, recording microhabitat features for each frog located (substrate type, height and distance from water). Microhabitat availability varied between dry and wet seasons in all streams, and overall microhabitat diversity changed in two streams. Bokermannohyla nanuzae seemed to have a niche contraction in the presence of Bokermannohyla martinsi, but this only happened during the dry season. Microhabitat requirements during the wet season may be closely linked to similar reproductive needs that probably represent a strong selective pressure, forcing niche overlap.  相似文献   

13.
《Journal of Natural History》2012,46(29-30):1891-1910
One hundred and ninety-one frogs collected in Papua New Guinea from 10 species of the genus Litoria, namely, L. angiana, L. arfakiana, L. caerulea, L. congenita, L. eurynastes, L. gasconi, L. infrafrenata, L. iris, L. kumae and L. modica, were examined for helminths. Eighteen species of helminths were found: one species of Monogenea, Parapolystoma bulliense; three species of Digenea, Diplodiscus amphichrus, Halipegus zweifeli and Mesocoelium monas; 13 species of Nematoda, gravid specimens of Aplectana macintoshii, Cosmocerca novaeguineae, Falcaustra papuensis, Maxvachonia adamsoni, Maxvachonia flindersi, Maxvachonia ingens, Meteterakis crombiei, Moaciria moraveci, Parathelandros mastigurus, Physalopteroides milnensis, Pseudorictularia dipsarilis, Seuratascaris numidica, and larvae (in cysts) of Abbreviata sp. and, one species of Acanthocephala, Pseudoacanthocephalus bufonis. Mean number of helminth species per host species was 3.0 ± 1.4 SD (range 1–5), mean number of helminth species per infected frog was 1.1 ± 0.4 SD (range 1–2), and mean number of helminths per infected host was 33.3 ± 5.8 SD (range 1–36). Twenty-eight new host records and two new locality records are reported. The biogeography of the recovered helminths is discussed.  相似文献   

14.
Many agamid lizards are known to show sexual dimorphism in body shape, colour and ornamentation or a combination of these traits. Adult males of Salea horsfieldii have a discontinuous dorsal crest at the nuchal region, which is a sexually dimorphic character. However, there is no information about the age or size at which this dimorphic ornamentation develops and if the species exhibits sexual shape dimorphism (SShD). The authors studied the morphology of S. horsfieldii and found that its ornamentation is an ontogenetically stable character present in all males, including juveniles. Seven morphological characters were measured to determine if they exhibited SShD at adult and juvenile stages. Analysis of covariance was used to identify differences in morphology between sexes. The results show that only adults exhibited SShD, but not juveniles. Adult males had larger head and foot lengths in comparison to females of the same size. Larger head length in adult males is a sexual fitness trait, which increases bite-force during intra-sexual combats. Although the presence of sexually dimorphic ornamentation right from the juvenile stage is rare in agamids, S. horsfieldii is an exception . The role of sexually dimorphic ornamentation at juvenile stages remains unknown and requires further investigation.  相似文献   

15.
《Journal of Natural History》2012,46(23-24):1439-1452
We studied the breeding activities of Bokermannohyla nanuzae at an Atlantic Forest site in southeastern Brazil from August 2010 to April 2012. We described courtship behaviour, acoustic parameters of calls, egg clutch features and the egg-laying site, and characterized the reproductive mode. We recorded calling males and gravid females almost year-round, except for a few months in the dry season. We observed the interaction of five male–female pairs that exhibited stereotyped behavioural sequences including visual and tactile signals. We identified three different types of calls that we considered as the advertisement call and two types of courtship calls. Egg clutches were placed in rocky crevices with water or in streamside puddles, among rocks, that would be likely to be flooded as stream water level raises, which characterizes a reproductive mode different from the one previously recognized for this species. The breeding biology of B. nanuzae is complex, with elaborate courtship behaviour and signalling.  相似文献   

16.
《Journal of Natural History》2012,46(9-10):509-522
Three hundred and ninety‐nine individuals representing 10 species of Litoria and five species of Nyctimystes (Hylidae), L. arfakiana, L. bibonius, L. eucnemis, L. genimaculata, L. impura, L. infrafrenata, L. modica, L. nasuta, L. thesaurensis, L. wollastoni, N. gularis, N. kubori, N. papua, N. pulcher and N. semipalmatus collected in Papua New Guinea were examined for helminths. Gravid individuals representing one species of Monogenea (Parapolystoma bulliense), one species of Digenea (Mesocoelium monas), 18 species of Nematoda (Aplectana krausi, Aplectana macintoshi, Aplectana zweifeli, Cosmocerca novaeguineae, Falcaustra papuensis, Icosiella papuensis, Maxvachonia adamsoni, Maxvachonia ewersi, Meteterakis crombiei, Moaciria moraveci, Ochoterenella papuensis, Oswaldocruzia bakeri, Parapharyngdon maplestoni, Parathelandros allisoni, Parathelandros andersoni, Physalopteroides milnensis, Rhabdias australiensis, Seuratascaris numidica) and one species of Acanthocephala (Acanthocephalus bufonis) were found. Also included were immature forms representing one species of Cestoda (as a metacestode), three species of Nematoda (Abbreviata sp., Rictulariidae gen. sp., Ascarididae gen. sp. in cysts), one species of Acanthocephala (unidentified cystacanth), and one species of Pentastomida [Raillietiella sp. (nymph)]. The mean helminth species richness for infected hosts was 1.3±0.6 SD (range one to three species). Sixty‐seven new host records and two new locality records are reported.  相似文献   

17.
《Journal of Natural History》2012,46(35-36):2363-2371
Reproductive aspects of Ameerega braccata, a Cerrado endemic species of Dendrobatidae, were studied in the surroundings of the type locality of the species, Chapada dos Guimarães, mid-southern Mato Grosso State, Brazil. We found that males call mainly early in the morning and in the late afternoon. During courtship, the female approaches a calling male and tactile and visual communication occurs. Males call continuously while guiding females to the oviposition site, which may be situated as far as 24 m (in a straight line) from the initial encounter site. Spawn are deposited over fallen leaves on the soil surface or in burrows. Female snout–vent length and body mass did not explain the variation in ovary mass, or the variation in the number and size of post-vitellogenic oocytes. The results reported here for A. braccata might help to understand trends in the evolution of dendrobatids in open Cerrado environments.  相似文献   

18.
《Journal of Natural History》2012,46(43-44):2777-2791
Mortality rates are often high during the anuran tadpole stage, making demographic parameters in this phase of their life cycle important to the understanding of population demography. Nevertheless, information on mortality rates or population size is lacking for most Brazilian anurans. Herein we report on the demographic parameters of Phasmahyla jandaia (Hylidae) during the larval stage, including number of individuals through time, mortality rates and time of recruitment. Tadpole recruitment occurred year‐round, although froglet recruitment to the terrestrial habitat was restricted to the warm, rainy season. This trend seems to result in high plasticity of the tadpole developmental period. Mortality rates decreased with advancing tadpole stage, totalling 77% during the whole aquatic phase. Survivorship can be regarded as intermediate compared with other anurans for which data are available, and is in accordance with a high investment in egg size and the low number of eggs laid by P. jandaia.  相似文献   

19.
《Journal of Natural History》2012,46(1-2):117-129
The breeding biology and male territorial behaviour of the large-headed leaf-frog (Phyllomedusa megacephala) were studied in three temporary altitudinal streams located in the Cerrado biome of southeastern Brazil, during three consecutive years (2007–2009). Phyllomedusa megacephala showed significant sexual dimorphism, with females being bigger and heavier than males. Acoustic and physical interactions between males defending or not defending territories including amplectant and non-amplectant males, patrolling behaviour by males without established territories, and triple amplexus were observed. Neither males nor females were observed using visual cues when searching for mates. We found that males that were present at breeding sites in previous years bred more successfully and maintained territory better.  相似文献   

20.
《Journal of Natural History》2012,46(43-44):2689-2699
The selection of reproductive sites by anurans may be associated with each species’ behavioural restrictions, reproductive modes, morphology and physiology. We investigated the use of reproductive sites by Phyllomedusa azurea in an area of Cerrado, Central-Western Brazil, which has been modified by agricultural and cattle ranching. Reproductive activity was studied during the peak of the rainy season in two consecutive years. No correlation was found between male body size and position of the calling site, and calling sites did not vary among ponds. Conversely, the height and distance from the water margin where clutches were found varied among ponds. Phyllomedusa azurea used mainly Brachiaria sp. and Brachiaria humidicola grasses as calling sites and the grass Brachiaria sp. and the shrub Melochia villosa (Malvaceae) as oviposition sites. Calling males used the vegetation according to its availability; however, individuals seemed to exhibit significant preferences regarding the type of vegetation used for oviposition.  相似文献   

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