Breeding activity of Scinax centralis (Anura, Hylidae) in Central Brazil

From January, 1997 to April, 1998, we studied breeding activity in a population of Scinax centralis Pombal & Bastos, 1996, in the state of Goiás, inside the Cerrado Biome, Brazil. The behavior of males and females in the choruses, the relationships between environmental variables and the presence of individuals, the spatial distribution pattern, amplexus and clutches were analyzed. The breeding season occurred from November to May. The majority of males began to call when they entered the chorus; they were defending their calling sites against other males. We found a positive correlation between the number of females and males in the choruses, but no significant correlation was observed between the operational sexual ratio (OSR, number of reproducing females/number of reproducing males) and the number of calling males. OSR was highly male-biased; on average, there were 40 males for each female. The presence of individuals was positively correlated with air temperature of two previous days and negatively correlated with rainfall on the observation day. Generally, males were non-randomly distributed and satellite males were observed. Females were larger and heavier than males. Egg number, but not diameter of the egg, was correlated with the female size.

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Spatial-Temporal Population Dynamics of Male and Female Aedes Albopictus at a Local Scale in Medellín, Colombia

10.21203/rs.3.rs-300583/v1 ◽

2021 ◽

Author(s):

Carolina Camargo ◽

Catalina Alfonso-Parra ◽

Sebastián Díaz ◽

Diego F. Rincón ◽

Luis Felipe Ramírez-Sánchez ◽

...

Keyword(s):

Population Dynamics ◽

Spatial Distribution ◽

Aedes Albopictus ◽

Climatic Variables ◽

Vegetation Coverage ◽

Female Size ◽

Temporal And Spatial Distribution ◽

Male And Female ◽

Males And Females ◽

Temporal And Spatial

Abstract Background: Diseases transmitted by invasive Aedes aegypti and Aedes albopictus mosquitoes are major public health issues in the tropics and subtropics. Understanding the ecology of mosquito vectors is essential for the development of effective disease mitigation programs and will allow for accurate predictions of vector occurrence and abundance. Studies that examine mosquito population dynamics are typically focused on female presence or total adult captures without discriminating the temporal and spatial distribution of both sexes. Methods: We collected immature and adult mosquitoes twice monthly during a two-year period (2018 – 2019) in the Medellín Botanical Garden (Medellín, Colombia) and assessed: 1) the relationship between climatic variables/vegetation coverage and adult captures, 2) the temporal and spatial distribution of Ae. aegypti and Ae. albopictus during the study period, 3) the temporal and spatial distribution of Ae. albopictus males and females, and 4) the correlation of male and female size in relation to climatic variables and vegetation coverage. Results: We show that Ae. albopictus was the predominant species in the park during the study period. Adult captures were positively correlated with precipitation and relative humidity, and inversely correlated with temperature and wind speed. Spatial analysis showed that Ae. aegypti and Ae. albopictus were distributed at different locations within the surveilled area. Moreover, we observed a spatial misalignment of Ae. albopictus males and females—the majority of males were located in the high vegetation coverage sites and the females in the medium vegetation coverage sites. Conclusions: Our work elucidates the differential dynamics of Ae. albopictus males and females, which is pivotal to develop accurate surveillance and the successful establishment of vector control programs based on the disruption of insect reproduction.

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Spatial and temporal population dynamics of male and female Aedes albopictus at a local scale in Medellín, Colombia

Parasites & Vectors ◽

10.1186/s13071-021-04806-2 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Carolina Camargo ◽

Catalina Alfonso-Parra ◽

Sebastián Díaz ◽

Diego F. Rincon ◽

Luis Felipe Ramírez-Sánchez ◽

...

Keyword(s):

Population Dynamics ◽

Spatial Distribution ◽

Spatial Analysis ◽

Wind Speed ◽

Aedes Albopictus ◽

Vegetation Cover ◽

Vegetation Coverage ◽

Female Size ◽

Male And Female ◽

Males And Females

Abstract Background Diseases transmitted by invasive Aedes aegypti and Aedes albopictus mosquitoes are public health issues in the tropics and subtropics. Understanding the ecology of mosquito vectors is essential for the development of effective disease mitigation programs and will allow for accurate predictions of vector occurrence and abundance. Studies that examine mosquito population dynamics are typically focused on female presence or total adult captures without discriminating the temporal and spatial distribution of both sexes. Methods We collected immature and adult mosquitoes bimonthly for 2 years (2018–2019) in the Medellín Botanical Garden. Collection sites differed in proximity to buildings and nearby vegetation, and were classified by their overhead vegetation cover. We used linear mixed models (LMMs) and Spatial Analysis by Distance Indices (SADIE) to assess the spatial distribution of Ae. aegypti and Ae. albopictus. Using our Ae. albopictus captures exclusively, we assessed (1) the spatial and temporal distribution of males and females using SADIE and a generalized linear mixed model (GLMM), (2) the relationship between climatic variables/vegetation coverage and adult captures using GLMMs and LMMs, and (3) the correlation of male and female size in relation to climatic variables and vegetation coverage using LMMs. Results Spatial analysis showed that Ae. aegypti and Ae. albopictus were distributed at different locations within the surveilled area. However, Ae. albopictus was the predominant species in the park during the study period. Adult Ae. albopictus captures were positively correlated with precipitation and relative humidity, and inversely correlated with temperature and wind speed. Moreover, we observed a spatial misalignment of Ae. albopictus males and females—the majority of males were located in the high vegetation coverage sites, while females were more evenly distributed. We observed significant associations of the size of our adult Ae. albopictus captures with precipitation, temperature, and wind speed for both sexes and found that overhead vegetation cover influenced male size, but observed no effect on female size. Conclusions Our work elucidates the differential dynamics of Ae. albopictus males and females, which is pivotal to develop accurate surveillance and the successful establishment of vector control programs based on the disruption of insect reproduction. Graphic Abstract

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Spatial distribution and associated flora of Alcantarea nahoumii, a vulnerable endemic species to rocky outcrops of the Serra da Jibóia, Bahia, Brazil

Rodriguésia ◽

10.1590/2175-7860201869219 ◽

2018 ◽

Vol 69 (2) ◽

pp. 503-514

Author(s):

Maria Josirene Souza Moreira Bastos ◽

Lucimário Pereira Bastos ◽

Everton Hilo de Souza ◽

Grênivel Mota da Costa ◽

Moema Angélica Chaves da Rocha ◽

...

Keyword(s):

Spatial Distribution ◽

Distribution Pattern ◽

Environmental Variables ◽

Relative Frequency ◽

Rock Slope ◽

Spatial Distribution Pattern ◽

Absolute Frequency ◽

Exposed Rock ◽

Absolute Density ◽

Associated Species

Abstract The objective of this study was to characterize the spatial distribution pattern at different altitude gradientes as well as to investigate the flora associated with A. nahoumii, considered to be endemic and vulnerable. The study was carried out in Serra da Jibóia, Santa Teresinha, Bahia, Brazil. An inventory was conducted of Young and adult A. nahoumii specimens along with taxonomic identification and quantification of the associated species. The cover percentage of A. nahoumii, rock slope, organic matter percentage and exposed rock percentage were calculated, as well as the following phytosociological parameters: absolute density, relative density, absolute frequency, relative frequency, and dominance of A. nahoumii. For the spatial distribution, three indices were tested (Morisita, McGuinnes and Payandech). Canonical correspondence analysis was also applied to test the association of the environmental variables with the species in the community. A total of 1,660 individuals were encountered and classified according to taxonomy in 17 families, 25 genera and 28 species. The spatial distribution pattern of the A. nahoumii population is aggregate. The results demonstrate that the population structure of A. nahoumii is stable, but events such as fires and extractive exploitation make the species vulnerable, along with the other species that inhabit the area.

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Reproductive aspects and adaptive relative growth of the tropical crab Goniopsis cruentata

Animal Biology ◽

10.1163/15707563-00002422 ◽

2013 ◽

Vol 63 (4) ◽

pp. 407-424 ◽

Cited By ~ 5

Author(s):

José J.P.R. de Lira ◽

Tereza C. dos S. Calado

Keyword(s):

Seasonal Variation ◽

Brood Size ◽

Early Stage ◽

Reproductive Traits ◽

Female Size ◽

Relative Growth ◽

Evolution Of Life ◽

Egg Number ◽

Males And Females ◽

One Year

The knowledge of reproductive traits is essential to the comprehension of the evolution of life history and population dynamics of a species. Here, we evaluate morphological maturity, relative growth, fecundity, relationship between size and fecundity, brood loss, and seasonal variation of brood size in the crab Goniopsis cruentata. Crabs were collected during a period of one year in a tropical mangrove, Northeast Brazil. Males matured at smaller sizes than females. Compared to other studies, this result indicates that there appears to be no pattern of sexual maturity between the sexes in this species, with both sexes maturing earlier or later. The relative growth of the gonopod length (males) and abdomen width and length (males and females) is clearly related to different sex roles, i.e., incubating eggs in females and maximizing the number of mates in males. Fecundity increased with female size and was similar to the fecundity of previous studies with the same species. Egg number of females incubating early-stage eggs was higher than those incubating late-stage eggs, indicating loss of eggs during embryogenesis. Fecundity of females occurring in the dry season was higher than that of females occurring in the rainy season, indicating seasonal variation of brood size.

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