# Odostomia kromi

Odostomia kromi is a species of sea snail, a marine gastropod mollusc in the family Pyramidellidae, the pyrams and their allies.

## Description

The shell grows to a length of 1.7 mm (0.067 in). Its distribution is largely throughout the Mediterranean Sea. Odostomia kromi is a marine gastropod mollusk within the family Pyramidellidae, also known as the pyrams. This family, comprising over 6,000 species, includes small, parasitic or commensal snails that often attach to host organisms for nutrients. O. kromi was first described in 1984 by researchers van Aartsen, Menkhorst, and Gittenberger. It is part of the genus Odostomia, which contains numerous minute sea snails distinguished by their small, narrow, and often elongated shells. Members of Odostomia are generally classified within the superfamily Pyramidelloidea and belong to the order Heterobranchia, a diverse clade that exhibits varied reproductive and anatomical adaptations.
The shell of Odostomia kromi typically measures approximately 1.7 mm in length, showcasing a translucent and whitish appearance that aids in camouflage within the sedimentary ocean floor. Its conical, pointed shell structure is finely textured with spiral ridges, contributing to its streamlined shape, which is ideal for burrowing or gliding over soft, sandy substrates. The opening of the shell, or aperture, is oval, with a slightly curved outer lip, while the inner structure includes a columella, a small internal fold that helps anchor the snail within its shell.

## Distribution and Habitat

This species occurs in the following locations:
* European waters (ERMS scope)
* Portuguese Exclusive Economic Zone
* Spanish Exclusive Economic Zone : Alboran Sea
Odostomia kromi is primarily distributed within the Mediterranean Sea, especially near the Alboran Sea, and extends to the Atlantic coastal waters of Portugal and Spain. This subtropical distribution aligns with the typical habitats of Pyramidellidae, as they often occupy temperate to subtropical marine environments. O. kromi is found in benthic zones, meaning it resides on or just below the sea floor, where it can blend in with fine sediments and avoid detection from predators. These zones are abundant with organic material and detritus, essential for sustaining the tiny gastropods. Pyramidellid snails, including O. kromi, are often ectoparasitic, occasionally attaching to the tissues of larger invertebrates, particularly echinoderms and annelid worms.

## Ecological Role and Conservation

As part of the benthic ecosystem, Odostomia kromi plays a role in nutrient cycling and energy flow. By preying on microscopic organisms or acting as parasites, these snails contribute to controlling populations of other marine invertebrates, indirectly impacting sediment health and biodiversity. Despite its small size and elusive nature, O. kromi contributes to the overall stability of its ecosystem. Currently, O. kromi has not been evaluated by the IUCN Red List, and it holds no specific conservation status under CITES or CMS, likely due to its small size and lesser economic or ecological visibility. However, ongoing habitat changes in Mediterranean regions, such as coastal development, pollution, and climate change, could indirectly impact these populations by altering benthic habitats.