Gulf Coast pygmy sunfish

The Gulf Coast pygmy sunfish, Elassoma gilberti, is a species of pygmy sunfish endemic to Florida, United States. This species can reach 2.5 cm in standard length.

Etymology
The fish is named in honor of Carter R. Gilbert (1930-2022), who was the Curator of Fishes at the Florida Museum of Natural History from 1961 to 1998, because of his many contributions to the study of North American fishes.

Elasoma gilberti is closely related to E. okefenokee, and the two species are nearly indistinguishable in appearance. E. gilberti in general has four preopercular canal pores, while E. okefenokee on average has three. The average number of anal fin rays is seven in E. gilberti and eight in E. okefenokee. The female E. gilberti often expresses a blue patch of color behind her eye, while the E. okefenokee does not.

Range and ecology
This species occurs in northwestern Florida and southwestern Georgia in the lower Suwannee River drainage and other Gulf of Mexico drainages from the Waccasassa River west to Choctawhatchee Bay. They are usually found in slackwater environments, among dense aquatic vegetation and leaf litter, where they feed mainly on tiny insects, crustaceans, and worms.

Spawning
Elassoma gilberti will breed in a wide range of water conditions, and spawning has been confirmed in both 0 DH and 20 DH water. Males require a region of dense living or artificial rooted aquatic plants to claim as territory to woo females in to spawn. Each spawning male claims about a cubic foot of volume as his territory. The males spend their time patrolling around their territories and dancing to catch the females' attention. When dancing, they wiggle their dorsal, anal, and caudal fins to show off their bright blue iridescence. Then, suddenly, they do a full stop, holding completely still for a few seconds with no visible motion. After the pause, they continue dancing again, often moving up and down in their eagerness to woo the female into their respective clumps of dense plants. Females swim in and out of the males' territories to spawn. The male then guards the spawn site until the eggs hatch, chasing females and other males away.

It takes about three to four days for the eggs to hatch. At this point, the male stops protecting the spawn site and becomes receptive to spawning again. <!--E. gilberti will spawn year round if well fed. It is popular to feed the fry microworms, which can survive for one to two days underwater and thus can be added to the tank daily to provide a constant food supply for the young. Fry lay motionless on the bottom for the first week or so after hatching. The first fry begin to swim in small bursts eight days after the eggs were laid. Male fry can color up at one half inch of size, which occurs at approximately four to five months if the fry were well fed.

Tank Mates
Because their maximum size is only one inch long, bigger fish do not make good tank mates with Elassoma gilberti. The fry and juveniles remain at less than a half inch long for three or four months. Here is a scaled photo of a fully grown Elassoma gilberti male (picture taken by Erica Wieser and used with permission): http://gallery.nanfa.org/v/members/EricaWieser/scaled+photo+number+2.jpg.html The scale reference is one inch.

The most common problem with introducing a new species of fish into a pygmy sunfish species-only tank is that the pygmy sunfish will stop spawning. Because these fish have a 1-3 year life span and look quite drab when not spawning, it is desirable to keep them spawning continually. For this reason, pygmy sunfish are often kept in species-only tanks. Tetras and barbs scare Elassoma gilberti with their rapid motion, and will force even a well fed, healthy population of gulf coast pygmy sunfish to spend the majority of their time hiding in the plants. Large, colorful guppies and bettas will also scare Elassoma gilberti into the plants, but small clear and white guppies have less of an effect. Keep in mind when choosing tank mates that the color blue is a marker for dominance in Elassoma gilberti, and that gilberti will interpret a dark blue betta or platy as being the dominant male. They will hide whenever that dark blue fish is nearby.

Photos
Male in breeding colors Photo copyright Erica Wieser and used with permission.

Size comparison of female with Lymnaea snail Photo copyright Erica Wieser and used with permission.

Fry (baby fish) iridescent in the sunlight Photo copyright Erica Wieser and used with permission.

Male's normal coloration when not breeding at the moment  Photo copyright Erica Wieser and used with permission.

A male blanched out (they are normally grey or black with blue stripes) Photo copyright Erica Wieser and used with permission.

Example of an aquarium that maintains a breeding population of Elassoma gilberti Photo copyright Erica Wieser and used with permission.

Videos
Little male chased away by big male as he was wooing a female

Male defending his territory

Courtship dance

Female playing in the current

Male chasing female out of his territory after spawning to guard the eggs

Fry searching for food among the blackworms, which are food for the adults

Male wooing a female into his territory to spawn -->