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1.
《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   

2.
Nests of Schneider’s dwarf caiman, Paleosuchus trigonatus, were located in the forests around three streams that drain into the Xingu River, Brazilian Amazonia, in October 2014. Camera traps were installed at the edge of four nests to document predators and female parental care. At two nests, females unsuccessfully defended their nests against one or more giant armadillos, Priodontes maximus, and nine-banded armadillos, Dasypus novemcinctus. Both armadillo species responded to the attack by fleeing and returning on the opposite side of the nest by going around the tree under which the nest was located. Giant armadillos have never before been recorded consuming caiman eggs and their diet has been described as consisting mostly of ants and termites. Another species of armadillo, Cabassous unicinctus, was also registered digging into a nest and probably consuming eggs, though it is generally considered to be primarily insectivorous. A tayra (Eira barbara), lizard (Tupinambis teguixin) and coati (Nasua nasua) were also registered taking eggs from nests during the day, but we obtained no registers of nest defence by caimans during the day. The three nests were attacked after 60 days of incubation, when the eggs were well developed.  相似文献   

3.
《Journal of Natural History》2012,46(17-18):1025-1057
The genus Martarega comprises 15 species and nine of these have been recorded in northern Brazil. Martarega pydanieli sp. nov. from Rondônia, while Martarega nieseri sp. nov. and M. barcelos sp. nov. from Amazonas are described here. Six known species are recorded in the Brazilian Amazonian Region (Amazonas, Pará, Rondônia and Roraima): M. brasiliensis, M. chinai, M. gonostyla, M. membranacea, M. oriximinaensis, and M. uruguayensis. At the outset of this survey the genus Martarega of the Brazilian Amazonian Region held 12 species, but no specimens of M. mcateei, M. hungerfordi, and M. williamsi were collected in the regions sampled. Martarega brasiliensis is newly recorded from Roraima, which comprises the first record of members of this genus in this State. Martarega uruguayensis is newly recorded from Pará and Rondônia, while M. gonostyla from Rondônia. Distinct keys to males and females of Martarega occurring in this region, including these new species, are provided.  相似文献   

4.
《Journal of Natural History》2012,46(25-26):1749-1763
Specimens of Chinavia musiva were collected in Parque Estadual do Espinilho (Barra do Quaraí County, RS, Brazil). Insects were reared under controlled conditions (24±1°C; RH 70±10%; 12h L:12h D), and fed on green beans (Phaseolus vulgaris L.). Eggs of C. musiva differ from the pattern observed in other species of the genus due to chorion colour and surface, and aero‐micropylar processes, number and shape. Exclusive features of the species in the nymphal stage are head and thorax dull; variegated pattern of abdomen, and openings of the scent glands in conspicuous tubercles. Developmental time was, on average, 52 days; females laid more frequently egg masses with 14 or 42 eggs. Females collected from the field as nymphs exhibited higher reproductive performance than females reared on green beans as nymphs and adults, suggesting that wild hosts could be essential for the species life cycle.  相似文献   

5.
Some species of Leptodactylus of the L. pentadactylus group lay their eggs outside water but the tadpoles need to reach water to complete the larval phase; other species complete development in terrestrial nests. Here we present details of the reproduction of L. labyrinthicus in south‐eastern Brazil. The proportion of tadpoles and trophic eggs in aged egg clutches was determined, as well as the growth of the tadpoles while in the nest. The gut contents of tadpoles that were in egg clutches of frogs were analysed. Adult males did not differ from females in size and had hypertrophied forearms and an enlarged spine on the thumb. Reproduction was initiated with the first rains of August/September and extended to mid‐January. Calling and spawning occurred at permanent or temporary water bodies. The foam nests were built in excavated basins outside of, but close to the water. The male determined the place of the basin construction; after amplexus, the female completed the excavation. The amplexus was axillary. One female spent the day after spawning in the foam. The eggs were pale grey, the yolk averaging 2.3?mm in diameter. The mean number of eggs was 2101 per egg clutch. The number of tadpoles in individual nests varied between 0.05% and 11.40% in relation to the total laid eggs. The tadpoles entered water when rains flooded the basin. The tadpoles grew to 12 times the weight of an individual egg while in the nest; no nesting tadpole was beyond stage 25. The longest time we followed tadpoles in a nest was 25 days. Tadpoles were found preying upon eggs of three other frog species and upon conspecific eggs. Males fought by grasping each other in a belly‐to‐belly position; the powerful arms and the thumb spines represent weapons. Even though males can reach maturity in the season following birth, small size would prevent them from establishing their own territory. All the species of the L. pentadactylus group may build their foam nests within excavated basins. The basins may protect the eggs and embryos from cannibalistic tadpoles and may have an anti‐desiccation effect. In order to produce trophic eggs, the female may delay laying additional unfertilized eggs until after the male has abandoned the foam nest. Anuran eggs represent an important food item for tadpoles after they leave the nest.  相似文献   

6.
Population and reproductive behaviour aspects of the glass frog Espadarana prosoblepon are well known for populations from Central America, but similar information is lacking for populations from South America. We recorded the reproductive ecology of a population of the glass frog E. prosoblepon in the city of Armenia, Central Andes of Colombia. With weekly surveys with mark-recapture between December 2013 and November 2015, we monitored activity patterns and evaluated if the probability of males mating is associated to their body size or to chorus tenure (i.e. the number of nights a same individual is calling for attracting a mate). In addition, upon observing an amplexus, we recorded the behaviour of the individuals until oviposition and noted characteristics of egg clutch. We recorded 47 males and 32 females, nine amplexus events, eight ovipositions, and 21 egg clutches (35.4 ± 4.79 eggs per clutch, = 29). Activity of males and females and the number of egg clutches were positively correlated to rainfall. Mating success of males was not associated to their body size, but it was positively associated to longer chorus tenure; clutches from large females had a higher number of eggs than clutches from small females. Oviposition occurred on average 3.76 ± 1.74 hours after we first observed the amplexus, occurring 93.1% of the time in fronds of Selaginella geniculata at an average height of 1.58 ± 0.44 m. After the oviposition, the male left the site, while the female remained between 30 and 45 min, partially covering the eggs. The reproductive behaviour of E. prosoblepon did not vary widely between a population in Costa Rica and our population in time to oviposition, and mating success of males associated to chorus tenure; however, in our study population we recorded a larger clutch size and the preference for S. geniculata fronds as oviposition substrate.  相似文献   

7.
Summary

Information is sparse on the ecology of the larval and juvenile stages of the lobster (Homarus gammarus (L.)). A knowledge of the distribution and particularly the abundance of this species is vital for the development of stock-recruitment theory. Attempts were therefore made to determine the distribution of juvenile lobsters in the field by Scuba diving and the fishing of small mesh traps.

As these initial attempts were of very limited success, lobsters were reared in the laboratory to study their substrate preferences and behaviour. Juvenile lobsters (~8 mm carapace length) selected coarse substrates which offered suitable crevices, or burrowed extensively in fine, cohesive mud. The rock crevice habitat is widely used by adult lobsters, but the construction of complex mud burrows has not previously been described for this genus. The burrowing behaviour of juvenile lobsters and the structure of the burrows are discussed. Juvenile lobsters appear to have wide habitat tolerances enabling them to inhabit a variety of substrate types. The estimation of juvenile lobster abundance is likely to be extremely difficult.  相似文献   

8.
The gray-headed tody-flycatcher Todirostrum poliocephalum is a passerine endemic to the Atlantic Forest of Brazil. We describe the nest and nesting behaviour of this species and investigate geographical variation in breeding traits in the genus using data from the literature, museum collections, and citizen science projects. We located 21 nests of the gray-headed tody-flycatcher, 13 of which we monitored. Nest height above the ground averaged 3.3 ± 3.4 m (n = 21). Nests were built over a 16.8 ± 5.6-day period (n = 6) by both adults. Clutch sizes ranged from two to three eggs, with a mean of 2.9 ± 0.3 eggs (n = 10). Eggs measured 16.6 ± 0.5 × 12.0 ± 0.5 mm (n = 23) and weighed 1.1 ± 0.1 g (n = 19). Mean incubation period was 17 days (n = 3) and mean nestling period was 15.5 days (n = 2). Apparent reproductive success was 30.8%, with predation being the primary cause of nest failure (46.1%). Mayfield’s reproductive success was 25.9%, and daily survival rates for eggs and nestlings were 0.957 and 0.971, respectively. Clutch sizes increased with latitude, but temperature and precipitation seasonality had very low importance in explaining clutch size variation.  相似文献   

9.
Two new species of the freshwater planktonic copepod genusMastigodiaptomusM. maya and M. reidae—are described from material collected in southeastern Mexico. This neotropical genus is known to be distributed mainly in the southern part of the United States, Mexico and Central America, and now embraces eight species. Of these, six occur in Mexico. Both new species seem to be closely related to M. texensis and M. albuquerquensis. It is probable that this group of Mexican species represents a northwards radiation from the Proto-Antilles-Central America region into the continent, eventually reaching North America. A key for the identification of the known species of the genus is provided.  相似文献   

10.
Three cryptic species of the genus Munida from New Caledonia, previously identified as M. tuberculata Henderson, , M. notata Macpherson, and M. clinata Macpherson, , are described and illustrated. The three species are identified by subtle and constant morphological characters, which match clear differences in molecular sequences (16S rDNA and COI genes). The results also confirm the importance of several of these characters (e.g. length of the antennular and antennal spines) in the taxonomy of the genus Munida.  相似文献   

11.
12.
《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   

13.
The Geometrine genus Metallolophia is revised. In addition to the 11 species known, five new species are described as new. All the known species are redescribed and lectotypes are designated for M. opalina (Warren), M. arenaria (Leech) and M. danielaria (Oberthür) (=M. arenaria (Leech)). The male of M. ocellata (Warren) and the females of M. medullosa Inoue and M. devecisi Herbulot are described for the first time. The generic characters based on all species are summarized and a key to all taxa is given. Illustrations of moths and genitalia are presented. The new and revised taxa are: Metallolophia purpurivenata sp. nov., Metallolophia cuneataria sp. nov., Metallolophia inanularia sp. nov., Metallolophia flavomaculata sp. nov., Metallolophia stueningi sp. nov. and Metallolophia ostrumaria Xue, syn. nov. (of Metallolophia albescens Inoue).  相似文献   

14.
ABSTRACT

Thraupis is a genus of the American endemic Thraupidae (subfamily Thraupinae), comprising seven species that inhabit tropical forests to urban centres. The Sayaca Tanager (Thraupis sayaca) is a disturbance-tolerant species of high representativeness in plant-frugivore networks, but information on its breeding biology is scarce and often restricted to non-systematic surveys. We studied the breeding biology of the T. sayaca, following 39 active nests in a periurban area of southeast Brazil during two breeding seasons (2017/2018, 2018/2019). The breeding season ranged from early September to middle December, and the nests were placed in native and exotic plants and human buildings (nest height above ground: 3.35 ± 1.73 m, mean ± SD). Only females incubated and brooded, but both adults built the nests, fed the nestlings, and removed their faecal sacs. Clutch size was 2.86 ± 0.38 eggs and nest attentiveness was 71.2%. The incubation and nestling periods were, respectively, 13.4 and 17.4 days. Males and females did not differ on nestling provisioning and nest sanitation rates. Nestling provisioning (13.35 ± 6.25 trips/hour) increased with nestling age, while mean brooding time was 37.2% and decreased with nestling age. Apparent nest success was 38.7%, and nest survival according to the Mayfield method was 27.2%. Five nests (20.8%) were parasitised by the Shiny cowbird (Molothrus bonariensis), and we recorded five events of nest-site reuse. We concluded that the most remarkable breeding traits of T. sayaca in comparison with close-related tanagers are the use of anthropogenic nest sites, the higher clutch size and number of feeding trips, and the longer nestling period.  相似文献   

15.
Iridophora clarki gen. nov., sp. nov., Megaselia sembeli sp. nov. and M. kodongi sp. nov. are described. The females of I. clarki attack the workers of the ant Iridomyrmex cordatus (Smith). The same ant species is also attacked by M. sembeli, and the morphology of this species indicates that it is close to P. beirne Brues, the typespecies of the genus Plastophora. The loss of the type-material of the latter species prevented synonomy of the genus when it was re-evaluated (Disney, 1978). The detailed examination of M. sembeli now indicates that the genus Plastophora is a synonym of Megaselia (syn. nov.). A consequence is that P. dubitata Brues, 1935 becomes a homonym of M. dubitata (Malloch, 1912) and the replacement name M. bruesi nom. nov. is proposed. The females of M. kodongi attack workers of a species of Pheidologeton which forages on the forest floor. The habit of Iridomyrmex cordatus in using covered ways up trees appears to be related to its extreme vulnerability to attack by these two phorides.  相似文献   

16.
17.
《Journal of Natural History》2012,46(17-18):1101-1117
In this study we describe trophobiosis between ants and Eurystethus microlobatus (Hemiptera: Pentatomidae) at a highland quartzite rocky outcrop in southern Espinhaço Range, southeastern Brazil. We found stinkbugs exclusively on the mistletoe Psittacanthus robustus (Loranthaceae). The stinkbug species is gregarious, forming dense clusters, with females guarding eggs and young nymphs. In addition, this species presents cryptic colouration and most individuals were located on roots and shoots, camouflaged within the bark. Eurystethus microlobatus produced honeydew by day and night, and four ant species attended aggregations: Camponotus rufipes, Camponotus crassus, Camponotus melanoticus and Cephalotes pusillus. Camponotus rufipes was the most frequent and aggressive, and the only species to attend the stinkbugs by day and night. This is the first documented case of trophobiosis between true bugs and ants in the New World.  相似文献   

18.
19.
Metopina ciceri sp. nov. is described on the basis of males with reduced wings, fully winged females, blind females with reduced wings, pupae and larvae. The larvae infest the root nodules of the chickpea, Cicer arietinum L. The blind-morph females are considered to be congeneric with the type species of the genus Typhlophorina Silvestri and this genus is synonymized with Metopina. The males, if procured in isolation, would have been assigned to a separate genus. The evolution of sexual dimorphism and dimorphic females in M. ciceri is discussed in relation to a speculative scenario involving juvenile hormone and heterochrony. It is also speculated that dispersal is undertaken by the sighted fully-winged female morph only. These speculations and the question of whether the infestation of C. arietinum by M. ciceri affects yield remains to be investigated.  相似文献   

20.
Bahadzia setimana sp. nov. from South Andros, and B. obliqua sp. nov. from Cat Island, both in the Bahamas, are described. The recently described genus Bahadzia now contains five closely related taxa, each apparently confined to a single island or isolated group of islands, in a restricted area of the West Indies, ranging from Haiti in the south to the northern Bahamas.

The present discoveries show not only that low-salinity groundwaters of the West Indies have a marked degree of insular endemism, but that the high-salinity anchihaline habitats possess endemics in certain groups as well.

Current models which seek to explain the evolution of stygobionts on Atlantic Islands are reviewed critically and the most likely synthesis is provided.  相似文献   

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