Queen Conch Shell

Queen Conch Shell, Aliger gigas

Queen Conch Shell, Aliger gigas. Shell collected from coastal waters of Cancun, Yucatán, April 1996. Size: 19.1 cm (7.5 inches) x 14.5 cm (5.7 inches). Collection, photograph and identification courtesy of Bob Hillis, Ivins, Utah.

Queen Conch Shell, Aliger gigas. Shell collected from coastal waters of Bimini, Bahamas, October, 2004. Size: 13.0 cm (5.1 inches) x 8.8 cm (3.5 inches). Collection, photograph and identification courtesy of Bob Hillis, Ivins, Utah.

Queen Conch Shell, Aliger gigas. 1902 Painting by Frank Weston Benson of child with a Queen Conch.

Phylogeny: The Queen Conch Shell, Aliger gigas (Linnaeus, 1758), is a gastropod member of the Strombidae Family of True Conch Shells. The genus Aliger is one of thirty-one genera in the Strombidae Family, and there are only two species in this genus. They are also known as the Pink Conch and in Mexico as Caracol Rosa, Caracol Rosado and Caracol Reina.

Description: Queen Conchs are a large and solid shell. Younger Queen Conchs have a spindle-shaped or fusiform outline. Older specimens become broader as the aperture lip begins to flare. They consist of nine to eleven whorls, with a very large body whorl. The spire is high and pointed. The margins of the whorls are sculpted with large triangular nodes or spines. The aperture is elongate and smooth. The outer lip of the aperture thickens and flares with age, and often becomes wavy. The siphonal canal is short and open. The exterior of the body whorl is sculpted with curved ridges, running the length of the whorl, and finer spiral ridges. The exterior color is orangish or pinkish in young specimens, becoming more tan with time. The periostracum is thin and brown. The interior is glossy, and usually light pink or peach, but in some cases it is magenta. The living animal is generally light to dark gray, though the mantle collar and siphon may be orange or yellow. Queen Conchs reach a maximum length of 35.2 cm (13.9 inches). As this species approaches maturity, is slows its growth and begins thickening its shell.

Habitat and Distribution: Queen Conchs are usually found on sand, often near seagrass, turtle grass, and manatee grass meadows. They range in depth from 0.3 m (1 foot) to 20 m (66 feet), though some sources extend that range to 35 m (115 feet). They are a subtropical to tropical species that are found in all Mexican coastal waters of the Gulf of Mexico and the Caribbean.

Ecology and Behavior: Queen Conchs are grazers that feed primarily on macro algae, unicelluar algae, and detritus. They are prey for crabs, lobsters, gastropods, sea stars, octopuses, and fish. They are gonochoric and reproduce sexually, with internal fertilization. The eggs are laid in sticky, string-like masses on the sand or seagrass. The reproductive season runs from March to October. A females will lay hundreds of thousands of eggs each season. Queen Conchs are known to host endoparasitic coccidian protists. Slipper Shells are frequent epibionts on the Queen Conch’s Shell. The Porcelain Crab, Porcellana sayana, and the  Conchfish,  Astrapogon stellatus, sometimes shelter in the conch’s mantle for protection.  Queen Conchs are edible and have been the target of  artisanal fisheries, commercial fisheries, recreational fisheries, and  shell collectors.

Queen Conchs had been one of the most economically significant species in the Caribbean, but depleted stocks have limited their value.  Most countries in the region recognize the Queen Conch as Threatened, and have passed various laws regulating or banning their harvest. Unfortunately, enforcement of regulations is lax in many areas and poaching continues to threaten the species with extirpation or extinction.

Synonyms: Eustrombus gigas, Lobatus gigas, Strombus (Eustrombus) gigas, Strombus canaliculatus, Strombus gigas, Strombus gigas verrilli, Strombus horridus, Strombus lucifer, and Strombus samba.