Intraspecific ecomorphological variations in Poecilia reticulata (Actinopterygii, Cyprinodontiformes): comparing populations of distinct environments

Abstract

ABSTRACT. Morphological variations, according to the principles of ecomorphology, can be related to different aspects of the organism way of life, such as occupation of habitats and feeding behavior. The present study sought to examine the intraspecific variation in two populations of Poecilia reticulata Peters, 1859, that occur in two types of environments, a lotic (Maringá Stream) and a lentic (Jaboti Lake). Due to a marked sexual dimorphism, males and females were analyzed separately. Thus, the proposed hypotheses were that the populations that occur in distinct environments present morphological differences. The morphological variables were obtained using morphometric measurements and the ecomorphological indexes. The data were summarized in a Principal Component Analysis (PCA). A Multivariate Analysis of Variance (Manova) was made to verify significant differences in morphology between the populations. Males and females showed similar ecomorphological patterns according to the environment they occur. In general the population from Maringá Stream had fins with major areas, and the Jaboti Lake population eyes located more dorsally. Additionally, others morphological differences such as wider mouth of the males from Maringá Stream, wider heads on Jaboti Lake females and more protractible mouths on males from Jaboti Lake suggest a set of environmental variables that can possibly influence the ecomorphological patterns of the populations, as the water current, availability of food resources and predation. In summary, the initial hypotheses could be confirmed, evidencing the occurrence of distinct ecomorphotypes in the same species according to the environment type.KEYWORDS. Ecomorphological indexes, Poeciliidae, habitat occupation, ecomorphotypes. RESUMO. Variações ecomorfológicas intraespecíficas emPoecilia reticulata (Actinopterygii, Cyprinodontiformes): comparando populações de ambientes distintos. Variações morfológicas, de acordo com os princípios da ecomorfologia, podem ser relacionadas a diferentes aspectos do modo de vida dos organismos, como a ocupação de hábitats e comportamento alimentar. O presente estudo buscou analisar essas variações em nível intraespecífico em duas populações de Poecilia reticulata Peters, 1859, que ocorrem em dois tipos de ambientes, um lótico (ribeirão Maringá) e um lêntico (lago Jaboti). Por apresentar um acentuado dimorfismo sexual machos e fêmeas foram analisados separadamente. Assim, a hipótese proposta foi de que as populações, que ocorrem em ambientes distintos, possuem diferenças morfológicas. As variáveis morfológicas foram obtidas por meio de medidas morfométricas e índices ecomorfológicos. Os dados foram sumarizados em uma Análise de Componentes Principais. Também foi feita uma Análise de Variância Multivariada para verificar se existe diferença significativa na morfologia entre as populações. Machos e fêmeas mostraram padrões ecomorfológicos semelhantes de acordo com o ambiente em que ocorrem. No geral, a população do ribeirão Maringá apresentou nadadeiras com maiore...

Urbanisation affects the diet and feeding selectivity of the invasive guppy Poecilia reticulata

“…Chironomidae larvae were the most consumed item in both groups of streams. This Diptera is a species also considered synanthropic (El‐Sabaawi, ), as well as P. reticulata , and are commonly found in the diet of tropical fish (Mise et al, ; Uieda & Pinto, ). In addition, the high abundance of Chironomidae larvae in urban streams (Callisto, Moretti, & Goulart, ; Xu, Wang, Duan, & Pan, ) resulted in the dominance of this food item in the diet of P. reticulata (i.e.…”

“…Therefore, identifying feeding adaptations of P. reticulata in alternative environmental conditions is fundamental for environmental assessment of streams, and this may provide insights on the establishment process of the species. In addition, the relevance of identifying species links in local food webs (Alves et al, 2016;Mise, Souza, Pagotto, & Goulart, 2015), allows a better understanding of the success of synanthropic species in urban environment (El-Sabaawi, 2018).…”

Ichthyofauna of Tributary Streams of the Cinzas River Basin, Paranapanema River, Brazil

“…Although the Ubá stream is considered the most conserved among the three, the presence of P. reticulata showed that it is not immune to human impacts, as this species is constantly related to degraded environments (Caetano et al 2016). Poecilia reticulata presents high reproduction rate and r-strategist behavior (Gomiero & Braga, 2007), phenotypic plasticity (Mise et al 2015) and tolerance to low oxygenation (Kramer & Mehegan 1981, Gomiero & Braga 2006, characteristics that contribute to its wide distribution (Ota et al 2018).…”

First integrative study of the diversity and specificity of metacercariae of Posthodiplostomum Dubois, 1936 from native and introduced fishes in the Caribbean

“…Individual hosts suspected to be Pa. managuensis were sub-adult and did not show all diagnostic characters, and belong to Cichlidae, in which morphological variability can complicate identification (Sowersby, 2017). In poeciliids, phenotypic plasticity and sexual dimorphism, with some species-specific characters only in males, can also hamper identifications (Schories et al ., 2009; Mise et al ., 2015). Identification of Pa. managuensis and Poe.…”