page_title: Aliger gigas
section_title: Soft parts
hierarchical_section_title: Aliger gigas / Anatomy / Soft parts
caption_attribution_description: English: Drawing of Strombus gigas from Duclos in Chenu, 1844
context_page_description: Aliger gigas, originally known as Strombus gigas or more recently as Lobatus gigas, commonly known as the queen conch, is a species of large edible sea snail, a marine gastropod mollusc in the family of true conches, the Strombidae. This species is one of the largest molluscs native to the Caribbean Sea, and tropical northwestern Atlantic, from Bermuda to Brazil, reaching up to 35.2 centimetres in shell length. A. gigas is closely related to the goliath conch, Lobatus goliath, a species endemic to Brazil, as well as the rooster conch, Lobatus gallus.
  The queen conch is herbivorous. It feeds by browsing for plant and algal material growing in the seagrass beds, and scavenging for decaying plant matter. These large sea snails typically reside in seagrass beds, which are sandy plains covered in swaying sea grass and associated with coral reefs, although the exact habitat of this species varies according to developmental age. The adult animal has a very large, solid and heavy shell, with knob-like spines on the shoulder, a flared, thick outer lip, and a characteristic pink or orange aperture.
context_section_description: Many details about the anatomy of Aliger gigas were not well known until Colin Little's 1965 general study. In 2005, R. L. Simone gave a detailed anatomical description. A. gigas has a long extensible snout with two eyestalks (also known as ommatophores) that originate from its base. The tip of each eyestalk contains a large, well-developed lensed eye, with a black pupil and a yellow iris and a small slightly posterior sensory tentacle. Amputated eyes completely regenerate. Inside the mouth of the animal is a radula (a tough ribbon covered in rows of microscopic teeth) of the taenioglossan type. Both the snout and the eyestalks show dark spotting in the exposed areas. The mantle is darkly coloured in the anterior region, fading to light gray at the posterior end, while the mantle collar is commonly orange. The siphon is also orange or yellow. When the soft parts of the animal are removed from the shell, several organs are distinguishable externally, including the kidney, the nephiridial gland, the pericardium, the genital glands, stomach, style sac and the digestive gland. In adult males, the penis is also visible.
caption: A drawing of an adult male Aliger gigas (from Duclos in Chenu, 1844) showing the external soft parts including the spade-shaped penis on the left. Separate details show the mouth, the distal portion of the penis, and both sides of the claw-like operculum
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