Marcel Vermeulen

Master's Student



 About me

My name is Marcel Vermeulen and I am studying Biology since 2018. I am currently under the supervision of Univ.Doz. Dr. Harald Ahnelt working on my master’s thesis: Phenotypic divergence across a flow regime in the Blackspot barb Dawkinsia filamentosa (Valenciennes 1844) (Teleostei: Cyprinidae) from Sri Lanka.

Dawkinsia filamentosa is a small freshwater cyprinid fish inhabiting a variety of habitats including rivers and lakes. They can be found in the lowlands of Sri Lanka (distribution limit at 600 m above sea level) and on the west side of the Indian peninsula, being one of the most common cyprinid fishes.
This study was designed to investigate potential phenotypic divergence of this species within freshwater ecosystems in Sri Lanka. The aim of this investigation is to determine if and which morphological trait differ between the populations inhabiting still and running waters and which are stable. Additionally, traits which differ between sexes will be accessed to avoid bias by sexual dimorphism.