Program PhD Students

Lara Roketenetz

Lara Roketenetz

Title: IB PhD Student
Department: Biology
Office: ASEC B201


I am primarily interested in molecular and evolutionary ecology of the milfoil weevil, Euhrychiopsis lecontei, a native beetle that is being used as an augmentative biocontrol agent for the aquatic invasive plant, Eurasian watermilfoil, Myriophyllum spicatum.  Although my research primarily involves investigating genetic differences among weevil populations, I am pleased to be working with a system that has an applied environmental aspect and has implications for reducing herbicide use in aquatic ecosystems. 

Research Accomplishments

1) Genetic characterization across the milfoil weevil’s native range.  Since the beetles are being reared from stock populations and purposely introduced into other waterbodies as a management tool for Eurasian watermilfoil, geographically-significant genetic variation of the weevils may affect the development of successful and acceptable biocontrol applications. Therefore, the primary purpose of this project is to provide a preliminary assessment of how widespread geographic variation is in the weevil.   Preliminary data suggest that some explanation other than isolation by distance may be playing a role in the genetic structuring of the milfoil weevil.  In conjunction, I will be looking at other species of weevil that are host specialists on milfoils, and proposing a phylogeny for this group.

2) Using GIS spatial data and analysis to characterize where and why genetic variation in Euhrychiopsis lecontei occurs throughout the United States. This project will attempt to address the causes behind any genetic structuring of the milfoil weevil. By examining haplotype distribution of the weevil throughout its range, I will use GIS technology to determine if distance; environmental variables such as hydrology, glacial refugia, climate, solar radiation or vegetation cover; or a combination of distance and environmental factors have structured the patterns of genetic variation in the weevil.

3) Determination of potential host range shift and sympatric speciation of Euhrychiopsis lecontei feeding on an ancestral host (Myriophyllum sibiricum) vs. a novel, introduced host (Myriophyllum spicatum). Phytophagous insects, such as the milfoil weevil, are ideal candidates for host range expansions/shifts for several reasons.  Importantly, they are host specialists that exhibit high host fidelity.  Milfoil weevils rely on their hosts for all their needs: food, courtship, mating, oviposition and development.  Because of the similarities in the ancestral and novel hosts’ morphology, it is likely that oviposition on the novel host initially happens by accident.  Conversely, the weevils may possess a genetic propensity, through an exaptation, to include the novel host in its oviposition repertoire. Weevil researchers have documented that adult weevils prefer to feed and oviposit on the plant species in which they completed development, therefore, intrinsic barriers to mating may develop over time. I am interested in investigating whether or not there are distinguishable differences among 12 microsatellite loci in milfoil weevils that feed on the different varieties of milfoil to determine if there are indications of host specialization (the earliest indication of sympatric speciation) within this species.


Miller J.K., L.D. Roketenetz and H.W. Garris. 2011. Modeling the interaction between the exotic invasive aquatic macrophyte Myriophyllum spicatum and the native biocontrol agent Euhrychiopsis lecontei to improve augmented management programs. BioControl. Published OnlineFirst. DOI 10.1007/s10526-011-9371-9.


2008: M.S. Biology. John Carroll University, University Heights, Ohio; 1998: B.A. Biology. Case Western Reserve University, Cleveland, Ohio