By Koaw - August 2025

GENERAL: The Plains Longear Sunfish (Lepomis aquilensis) (Baird & Girard, 1853), as of 2023, has been reelevated to species-status primarily due to the work of Kim et al. (2022) and accepted by authorities in the California Academy of Sciences and American Fisheries Society (Fricke et al., 2025; Page et al., 2023). As these authorities are willfully recognizing this species delimitation from the Longear Sunfish (Lepomis megalotis), so shall we in the KNFS community.

Basically, the Longear Sunfish had two species split from it: The Plains Longear Sunfish and the Gulf Longear Sunfish (Lepomis solis.)

IDENTIFICATION: (Mature specimens.)

1. Long, thick ear flap. (Varies tremendously but noticeably longer than a Green Sunfish or Bluegill.

2. That ear flap will most likely be entirely edged with a whitish-pinkish coloration. (Remember the Redbreast Sunfish does not have color on the back edge of that ear flap.)

3. Blue streaking on the upper lip will usually extend across the entirety of the upper lip. (The smaller Dollar Sunfish usually does not express this streaking across the lips entirety.) Keep in mind that the angle of light is very important to see this clearly! If it doesn’t appear to be there, move the fish’s head with the light to verify.

4. Blue streaking on the snout, cheek, and operculum that even extends behind the eye.

NOTE on LONGEAR vs. PLAINS LONGEAR: There is no definitive morphometric (measurable) or meristic (countable) feature to confidently distinguish a Longear Sunfish (Lepomis megalotis) from a Plains Longear Sunfish (Lepomis aquilensis) (Kim et al., 2022). Use the range map below to confidently determine your species noting that specimens caught within introgressed/overlapping zones could only be identified with genetics (where even then it may lead to ambiguous results!)

COLORATION: “Those specimens from Texas are weird,” is a comment I’ve often said over the last decade. The Plains Longear Sunfish, primarily found in Texas, expresses the most diverse phenotypic expression of colors and patterning than any of the other sunfishes within Lepomis. And it’s often gorgeous!

Don’t get caught up too much on coloration when attempting to identify this species. Some specimens may have an almost bicolor appearance of orange and light blue where the blue spotting is almost entirely hidden. Some specimens may flare up the strangest, boldest vertical lines along the side. The blue spotting on the sides may form an intricate lattice network with a distinct pattern or that blue spotting may be patchy and irregular, like most specimens within the Longear-Complex.

MALE vs FEMALE:

Males, especially during the warmer breeding season, will have the brightest colors. Most yellow colorations turn to dark oranges and reds, more vibrant blue iridescence appears on all the fins and sides, and the pelvic fins often turn a dark shade that may appear as an opaque black. This holds true for parental males. Satellite and sneaker males will appear as females.

Outside of breeding season it may be very difficult to tell males and females apart. Colors in both sexes will lessen and the swollen nape of the male will subside. Checking the size of the urogenital opening is not 100% reliable for sexing, but often enough mature males will show an opening that is ~50% in size of that of the anal opening while mature females usually approach 75% or more. Again, this is a general estimation technique.

THAT DARK BLOTCH: As is seen on congenerics such as the Green Sunfish (Lepomis cyanellus) and Bluegill (Lepomis macrochirus), a dark dorsal blotch may appear in the lower, backmost portion of the second dorsal fin. This dark blotch appears more often within populations of the Plains Longear Sunfish compared to populations of other species within the Longear-Complex.

RAKERS: This ID feature really is useful for hybrid identification. Having a basic understanding of the rakers for a local population will quickly and confidently help distinguish a hybrid from a pure specimen.

The Plains Longear Sunfish has short, often thick rakers. I made a video describing how to locate and find these rakers that is hosted on Koaw Nature’s Fishing Smarts YouTube channel.

LONGEAR-PLAINS LONGER & LONGEAR-GULF LONGEAR ADMIXED POPULATIONS: The range overlap regions of Longear-Plains Longear/Longear-Gulf Longear will, with high certainty, yield introgressed/hybridized specimens because of past secondary contact where gene swapping occurred and/or more recent hybridization events. The range overlap region provided is approximate, not exact. The full extent of the genetically admixed ranged has not been completely investigated (nor do I image it will be due to how expensive that would be.)

The anomalous MPA point in the central range exists in Clover Creek near Medon, TN and represents a genetic admixture of primarily Plains Longear and Northern, with some Longear. The northeast MS points represent populations that are strongly admixed by both Longear and Gulf Longear. In the western range, it appears that many Longear and Plains Longear populations exist together with limited gene swapping, although some populations exhibit strong admixture within the Arkansas-White-Red River Drainage, such as within Lukfata Creek, OK (Kim et al., 2022).

SIZE: The general accounting of this species reaching 24.0 cm (9.5 in) (Page & Burr, 2011) may still hold valid though most all specimens will be smaller. Typically expect most mature specimens to be around 3 inches (~75 mm) with large adults approaching 5 inches (127mm).

As of August 2025, the listed IGFA All-Tackle World Record for Lepomis megalotis is 0.79 kg (1 lb 12 oz), however, this is actually a Plains Longear Sunfish (Lepomis aquilensis), as this specimen was caught in New Mexico (IGFA, 2025); the recent splitting of the Longear Sunfish Complex has caused this discrepancy.

HABITAT: As it is with the other members of the Longear-Complex, find the Plains Longear in pools and calmer areas of creeks and rivers, often over rocky or sandy substrate. This species is fond of cover, such as fallen trees and undercut embankments, especially with intact root balls.

This species also does well in other impoundments such as ponds, lakes and reservoirs assuming pH and oxygen levels meet their biological demands.

FISHING: Grab that #10 hook and a chunk of bloodworm; I may be sounding like a broken record with this recommendation, but it works! I don’t often find a population of Longear-Complex species that isn’t socializing with Bluegill—so if you start off catching a bunch of Bluegill, keep at it, there may be some more timid Plains Longear lurking about.

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References:

Baird, S. F., & Girard, C. H. (1853). Descriptions of new species of fishes collected by Mr. John H. Clark, on the US and Mexican Boundary Survey, under Lt. Col. Jas. D. Graham. Proceedings of the Academy of Natural Sciences of Philadelphia, 6, 387–390.

Fricke, R., Eschmeyer, W. N., & van der Laan, R. (n.d.). ESCHMEYER’S CATALOG OF FISHES: GENERA, SPECIES, REFERENCES. [Dataset]. Retrieved October 16, 2024, from http://researcharchive.calacademy.org/research/ichthyology/catalog/fishcatmain.asp

IGFA. (n.d.). IGFA World Records Database Search. The International Game Fish Association. Retrieved October 26, 2024, from https://igfa.org/member-services/world-record/search

Kim, D., Bauer, B. H., & Near, T. J. (2022). Introgression and Species Delimitation in the Longear Sunfish Lepomis megalotis (Teleostei: Percomorpha: Centrarchidae). Systematic Biology, 71(2), 273–285. https://doi.org/10.1093/sysbio/syab029

Page, L. M., Bemis, K. E., Dowling, T. E., Espinosa-Pérez, H., Findley, L. T., Gilbert, C. R., Hartel, K. E., Lea, R. N., Mandrak, N. E., Neighbors, M. A., Schmitter-Soto, J. J., & Walker, H. J. Jr. (2023). Common and Scientific Names of Fishes from the United States, Canada, and Mexico (8th Edition). American Fisheries Society.

Page, L. M., & Burr, B. M. (2011). Peterson Field Guide to Freshwater Fishes of North America North of Mexico. Houghton Mifflin Harcourt.