Karyotyping as a Method to Verify Phylogenetic Relationships Among the Enneacanthus Species

Author

Ophelia A. Anderson, Lehman College City University of New YorkFollow

Date of Award

2025

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Biological Sciences

First Advisor

Dr. Joseph Rachlin

Second Advisor

Dr. Julio Gallego-Delgado

Third Advisor

Dr. Stephen Redenti

Abstract

The Enneacanthus genus consists of three species of freshwater fish endemic to eastern North America: E. obesus (Banded Sunfish), E. gloriosus (Blue Spotted Sunfish), and E. chaetodon (Black Banded Sunfish). Previous studies using molecular data suggest that E. obesus and E. gloriosus are more closely related, with E. chaetodon as the most distantly related species in the genus. This study investigates the phylogenetic relationship among the Enneacanthus species, using karyotype characteristics - chromosome number, morphology and fundamental number - as comparative metrics. Chromosome spreads were obtained from scale and gill epithelium samples collected between 1993 and 1994. Prepared slides were stained with Giemsa and analyzed with digital software applications to classify chromosome morphology based on Levan’s scale. E. obesus exhibited a diploid number of 2n = 48, E. gloriosus 2n = 50, and E. chaetodon = 44, possessing fundamental numbers of 104, 108, 96 respectively. All species displayed acrocentric, metacentric and submetacentric chromosomes. These findings reveal a greater cytogenetic similarity between E. obesus and E. gloriosus, supporting previous molecular evidence of their evolutionary relationships. These results highlight the value of cytogenetic studies in understanding phylogenetic relationships among Centrarchid fish.

Recommended Citation

Anderson, Ophelia A., "Karyotyping as a Method to Verify Phylogenetic Relationships Among the Enneacanthus Species" (2025). CUNY Academic Works.
https://academicworks.cuny.edu/le_etds/44