Variação do tamanho corporal de machos de Eulaema nigrita Lepeletier (Hymenoptera, Apidae, Euglossini). Resposta materna à flutuação de recursos?

Abstract

Em Eulaema nigrita Lepeletier, 1841, abelha comum, com ampla distribuição geográfica (MOURE 1950) e que habita preferencialmente áreas abertas, ou com influência antrópica (PERUQUETTI et al. 1999), os machos recebem menos alimento (SANTOS & GARÓFALO 1994a) e são, em média, 1,23 vezes mais leves ao emergir do que as fêmeas (t = 4,41; gl = 24; p < 0,001) (Tab. I). As células que receberão filhas, demandam cerca de 28% mais tempo para serem aprovisionadas do que células que receberão filhos, mas há grande variação na quantidade de alimento depositada em cada célula de cria (PEREIRA-MARTINS & KERR 1991). Estas diferenças podem chegar a até 85% (PEREIRA-MARTINS & KERR 1991), o que provoca variação no tamanho do corpo entre os indivíduos de ambos os sexos. Em São Carlos (São Paulo, 22º01'03"S, 47º53'27"W), machos coletados em ninhos foram muito variáveis em relação ao peso ao emergir [mín = 270 mg; máx = 391 mg; x = 336(±45,6DP) mg; n = 11; dados de um único ninho] e em coletas realizadas com iscas aromáticas é possível observar que ao longo do ano os machos de E. nigrita são muito heterogêneos em relação ao tamanho do corpo. As fêmeas também apresentaram grande variação em seu peso ao emergir [mín = 359 mg; máx = 474 mg; x = 421,2(± 48,5DP) mg; n = 5; dados de um único ninho]. ZUCCHI et al. (1969) (Minas Gerais, Brazil). It was also compared the body size variance between males and females sampled in three nests found in São Carlos (São Paulo, Brazil) and between these males and trapped ones. The smaller male (6.4 mm) was sampled in June and the bigger (8.9 mm) in July 1994, but the majority (32.3%) showed an intertegular span ranging from 7.8 to 8.0mm. The observed variance in body size was similar between males sampled in nests and trapped-males and the variance found inside a nest was similar between the sexes. However, males sampled in 1988/89 were bigger than 1994/95 males and males sampled in nests were smaller than trapped-males. The variance of the body size of males did differ between 1988/89 and 1994/95. In the first period differences between males sampled in dry or wet season was not observed, but in 1994/95 period the males sampled in dry season showed significantly greater variance in body size than males sampled in wet season. The body size variance did not differ between the wet seasons of 1988/89 and 1994/95. The body size variation, measured as the coefficient of variation in intertegular span, did not differ between males of E. nigrita (CV = 4.3%) and ground-nesting bees. These results show that the variation in body size of males of E. nigrita reflects that one found inside the nests of this bee, being similar among males and females. This variation is expected as result of ecological factors influences the nesting females. El Niño climatic events alone or in association with the lack of local food resources due to deforestation and presence of monocultures might play a role in observed body size variation. However this hypothesis is not sufficient to explain the observed body size variation i...

Biome variation, not distance between populations, explains morphological variability in the orchid bee Eulaema nigrita (Hymenoptera, Apidae, Euglossini)

“…It is known that the pollen offer throughout the year can influence the body size of El. nigrita individuals (Peruquetti 2003). Brazilian Savanna biome presents a seasonal variation in plant activities, with an increasing pollen availability during the wet season (Batalha and Martins 2004;Leite et al 2006).…”

Nesting Biology, Sexual Dimorphism, and Populational Morphometric Variation in Podium denticulatum F. Smith, 1856 (Hymenoptera: Sphecidae)

“…Wing size accessed by the centroid size showed significant higher variation among populations than wing shape (Table 7). This is an expected finding since size variation in insects are related to quantity and quality of the resources provided to the brood in the larval stage (Peruquetti, 2003;Campos et al, 2018). So, the higher wing size variation may reflect the differential offer of food resources at each environment, as the supply dynamics certainly vary temporally in different phytophysiognomies (Campos et al, 2018).…”

Size and shape in Melipona quadrifasciata anthidioides Lepeletier, 1836 (Hymenoptera; Meliponini)

“…Size, on the other hand, can be related to a pleiotropic effect. Therefore, adaptive factors such as climate, feeding (Peruquetti, 2003), altitude as found by Nunes et al (2007; may affect the local population size. Similarly, the effect of genetic drift must also be considered particularly in situations of habitat fragmentation and formation of small local populations, both of which intensify genetic drift, Spatial variation in Melipona quadrifasciata anthidioides decrease intra-population variance and increase interpopulation polymorphism.…”