Research Training Program

Amie Hankins
Southeastern Oklahoma State University
Durant, Oklahoma

Dr. Carole Baldwin, Ph.D.
Supervising Scientist
Department of Vertebrate Zoology
Division of Fishes

"There is no such thing as coincidence. Even the smallest chance encounters can become the greatest opportunities!"

Is Ophioblennius atlanticus more than one species?

The redlip blenny, Ophioblennius atlanticus, is a small (< 10”) fish that perches on coral or rocky reefs in shallow tropical waters throughout the Atlantic Ocean. A single species comprising two subspecies traditionally has been recognized based on an anatomical study published in 1962 by Smithsonian ichthyologist V. G. Springer. More recently, a study published in 2001 (Muss, et al.) compared DNA between individuals from different localities to determine genetic differences. The results suggest that O. atlanticus comprises not one but five different species, geographically distributed as follows: 1) Brazil, 2) Caribbean/western Atlantic, 3) eastern Atlantic (Saõ Tomé), 4) northern mid-Atlantic (Azores/Cape Verde), and 5) southern mid-Atlantic (Ascension/St. Helena). The purpose of the present study was to determine if there are anatomical features that support the recognition of five species of Atlantic Ophioblennius. Using digital or film techniques, 280 preserved museum specimens were X-rayed in order to make counts of fin rays and vertebrae. Specimens were then chosen from representative locations to “clear and stain,” a process that digests muscle tissue and stains both cartilage and bone, leaving a clearly visible skeleton. Finally, external structures and color patterns were examined. Five geographically distinct groups of Atlantic Ophioblennius can be identified on the basis of color patterns: 1) Brazil, 2) Caribbean/western Atlantic, 3) eastern Atlantic (Senegal), 4) northern mid-Atlantic (Azores/Canaries/Madeira) and 5) southern mid-Atlantic (Ascension/St. Helena). One of these (2), also can be distinguished based on fin-ray and vertebral counts. Further study of specimens with well-preserved pigment patterns is needed to determine to which group populations from certain eastern Atlantic localities (e.g. Saõ Tomé, Cape Verde) belong. Groups recognized in this study based on anatomy correspond well geographically with groups recognized in the genetic study, supporting the existence of at least five species of Ophioblennius in the Atlantic. Future studies of shorefishes with similar distributions could greatly increase estimates of fish diversity in the Atlantic.

This research was supported by a grant from the National Science Foundation Research Experiences for Undergraduates program, Award Number DBI 9820303.

Letter of Gratitude