The relative abundance, density, distribution pattern and relation among pit diameter and larvae body size of Myrmeleon brasiliensis Návas were evaluated in two microhabitats: sheltered and exposed. The total of 282 pits were found in sheltered microhabitat and only 50 in the exposed. The density of M. brasiliensis was between one and 43 individuals per m(2). The distribution pattern of larvae tended from pooled to regular distribution as the density increased. In both microhabitats the larvae body size was positively correlated with pit diameter.
Cannibalism is influenced by various intrinsic and extrinsic factors of the population, such as density, population structure, prey availability, habitat structure and famine. These factors acting either independently or in synergy determine the frequency of cannibalism. The aims of the present study were to evaluate the effect of density and food availability on the occurrence of cannibalism among Myrmeleon brasiliensis larvae (Neuroptera, Myrmeleontidae). In the present study, the occurrence of cannibalism among M. brasiliensis larvae was greater in the treatments that simulated an absence of food in situations of both high and low density. The search for food makes a larva move about to forage, thereby increasing the risk of falling into the trap of a neighboring larva. Thus, the cannibalistic behavior of M. brasiliensis larvae may be associated with opportunity rather than a direct attempt to pray on the same species.
In areas of the Cerrado biome (Brazilian savanna) with well-defined rainy and dry seasons, changes in climate and landscape affect the abundance and seasonality of insects. Larvae of the antlion Myrmeleon brasiliensis (N avas) (Neuroptera: Myrmeleontidae) are predators that build traps in dry sandy soil to capture prey. Here we determined the effect of rain on trap building by M. brasiliensis larvae in a riparian forest in the Cerrado biome. Differences in population size and developmental stage were found between the rainy and dry seasons. In the laboratory, the effect of rain-soaked soil on trap building was evaluated. Fewer antlion larvae were found in the rainy season. Moreover, a greater abundance of larvae in the final stage of development (third instar) was found in the dry season, whereas more first instars were found in the rainy season. The latter revealed that wet soil affects the trap building of the larvae, as smaller traps were built in the treatment with soaked soil (simulated rain), whereas the larvae in the control treatment (no rain) continued building traps with no change in size. The findings indicate that seasonality in the Cerrado biome exerts a short-term influence on M. brasiliensis larvae (larvae build fewer traps) as well as a long-term influence (association with life cycle).
Myrmeleon brasiliensis larvae are predators that use the sit-and-wait tactic to catch their prey, and to fulfill this pit-making funnel traps in the sandy soil and remain buried waiting for prey to slip. The objective of this study was to observe the predation behavior of larvae of M. brasiliensis in the three larval instars, for this leaf cut ant were collected manually and offered within the plastic pots as prey for 14 larvae of 1st instar larvae, 33 of 2nd and 3rd instar. It was counted the number of attacks of the predator to prey, the number of escapes from jail and the success of prey capture for each larva of M. brasiliensis. The larvae of M. brasiliensis 1st instar attacked more times its prey, followed by larvae of 2nd and 3rd instar. On the number of escape of prey, there was no significant difference in this behavior among larvae. Regarding the success in capturing prey, the larvae of 3rd instar were more successful, with a predation rate of 96.96%, followed by the larvae of 2nd (69.70%) and 1st instar (14.28 %).
In cases of asymmetric competition, larger individuals of many animal species have a greater probability of acquiring territory, gaining initial access to resources and finding a mate in comparison to smaller individuals. The competition among larvae of the antlion Myrmeleon brasiliensis (Neuroptera, Myrmeleontidae) is observed in the search for space for the construction of traps, in the forage for prey, and in the occurrence of cannibalism. The body size of the larvae is proportional to the size of the traps and the success of predation. Thus, larger specimens are better competitors in terms of capturing preys (asymmetric competition). The aim of the present study was to determine the effects of asymmetric competition in M. brasiliensis regarding the distance among these larvae. The study was developed in a permanent reserve area, located in the municipality of Aquidauana, from the Mato Grosso do Sul state, Brazil. For the laboratory experiments, we collected M. brasiliensis larvae and placed two larvae in plastic pots. The observations occurred by the visual search of traps, when a larva was seen in the diameter of its trap and the trap of its closest neighbor. Next, the trap size and the distance between them were measured for a period of 15 days. The results of the present study demonstrate that the largest M. brasiliensis larvae were outside the clusters. Within these clusters, the larvae moved away from each other because of the size of their traps, as the larger the neighboring larvae the greater the distance between them. Thus, the asymmetric competition between M. brasiliensis (larger larvae are better competitors) suggests a spatial arrangement among the larvae that is guided by the variable size of the trap.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.