# Complete mitochondrial genome of the Starhead Topminnow Fundulus dispar (Cyprinodontiformes: Fundulidae)

## TL;DR

This paper describes the complete mitochondrial genome of the Starhead Topminnow and helps clarify its evolutionary relationships within the Fundulus genus.

## Contribution

The first annotated mitochondrial genome of Fundulus dispar is presented, aiding in resolving phylogenetic relationships within starhead topminnows.

## Key findings

- The mitochondrial genome of Fundulus dispar is 16,564 bp long and includes 13 protein-coding genes, two rRNAs, 22 tRNAs, and a D-loop.
- Phylogenetic analysis shows Fundulus dispar is closely related to a group containing F. notatus and F. olivaceus.
- This data improves understanding of starhead topminnows' placement within the Fundulus genus.

## Abstract

Topminnows of the Teleost genus Fundulus serve as model organisms in ecotoxicology because of their broad physiological tolerance and propensity to breed in captivity. This research has been primarily limited to intraspecific comparisons, due to incomplete understanding of the evolutionary history of the genus, which is necessary for use of phylogenetic comparative methods. Interspecific relationships of topminnows remain unresolved, despite recent advances in mitochondrial and nuclear genome sequencing. Specifically, interrelationships of a group containing the starhead topminnows (Fundulus blairae, F. dispar, F. escambiae, F. lineolatus, and F. nottii) typically yield low node support values. Here, we present the first annotated mitochondrial genome of the Starhead Topminnow (F. dispar) and provide a phylogenetic hypothesis for starhead topminnows within the genus Fundulus. DNA was isolated from a specimen of F. dispar collected in Kentucky, USA. The circular genome is 16,564 bp long and contains 13 protein-coding genes, two ribosomal RNAs (rRNA), 22 transfer RNAs (tRNA), and one control region (D-loop). Our phylogenetic analysis supports a sister relationship between F. dispar and a group containing F. notatus and F. olivaceus. This data helps to resolve the phylogenetic placement of starhead topminnows.