Monostiolum tessellatum

Monostiolum tessellatum is a species of sea snail, a marine gastropod mollusk in the family Pisaniidae.^[1]

Monostiolum tessellatum
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
(unranked):	clade Caenogastropoda clade Hypsogastropoda clade Neogastropoda
Superfamily:	Buccinoidea
Family:	Pisaniidae
Genus:	Monostiolum
Species:	M. tessellatum
Binomial name
Monostiolum tessellatum (Reeve, 1844)
Synonyms[1]
Caducifer swifti (Tryon, 1881) Caducifer tessellatum (Reeve, 1844) Colubraria swifti (Tryon, 1881) Daphnella igniflua (Reeve, 1845) Fusus swifti (Tryon, 1881) (unnecessary combination) Pisania igniflua (Reeve, 1845) Pleurotoma igniflua Reeve, 1845 Pollia tessellatum (Reeve, 1844) Triton (Epidromus) swifti Tryon, 1881 Triton swifti Tryon, 1881 Triton tessellatus Reeve, 1844 (basionym)

Monostiolum tessellatum is a species of small sea snail, a marine gastropod mollusk within the family Pisaniidae [1]. Originally described by Lovell Augustus Reeve in 1844, this species is notable for its distinct shell ornamentation and its presence across a significant part of the Western Atlantic [1, 3].

Description

The shell of Monostiolum tessellatum typically reaches a length of up to 18 mm [1]. As suggested by its specific epithet "tessellatum" (meaning "tiled" or "mosaic-like"), the shell is characterized by a checkered or tessellated pattern, which often arises from the arrangement of its coloration and sculptural elements.

While a detailed, standalone description of Monostiolum tessellatum is not universally available, common features shared with other species in the genus Monostiolum (and the family Pisaniidae) generally include:

• Sculpture: The shell surface is often adorned with both axial (longitudinal) ribs and spiral cords, which intersect to create a reticulated or nodulose pattern. This intricate sculpture contributes to its distinctive appearance [4, 5].
• Shape: The shell is typically fusiform (spindle-shaped) to ovate-conical, with a moderately elevated spire [4].
• Aperture: The opening (aperture) is usually ovate, with a distinct siphonal canal at its base, which can be short and somewhat recurved [4].
• Outer Lip: The outer lip of the aperture may be thickened and often features internal denticles (small teeth) or lirae (ridges) [4].
• Columella: The columella (the central axis of the shell) can be smooth or bear small folds [4].

The color pattern, often described as tessellated, involves contrasting shades of brown, white, or cream, which can form a mosaic-like appearance.

Distribution

Monostiolum tessellatum is found in the Western Atlantic Ocean, with its distribution encompassing several regions:

• Caribbean Sea: A significant part of its range [1].
• Gulf of Mexico: Also a known habitat for the species [1, 2].
• Lesser Antilles: Specifically reported in this island chain [1].
• Cuba: Recorded in various locations around Cuba, including Havana and Guantánamo Bay [5].
• Aruba, Bonaire, and Curaçao (Dutch Caribbean): Also documented in these islands [6].

This wide distribution indicates its adaptation to the warm, tropical and subtropical marine environments of the Western Atlantic.

Habitat

Monostiolum tessellatum is a demersal species, meaning it lives on or near the seabed. Its recorded depth range is between 6 and 33 meters [7]. This suggests it inhabits shallow to moderate subtidal zones. Like many other members of the Pisaniidae family, it likely prefers sandy, muddy, or rubble bottoms, possibly in association with rocky substrates or coral reefs, where it can find its prey. As predatory snails, Pisaniidae species typically feed on other invertebrates.

Taxonomy and Synonyms

Monostiolum tessellatum was originally described as Triton tessellatum by L.A. Reeve in 1844 [1, 3]. It has gone through several taxonomic reclassifications and has accumulated numerous synonyms over time, reflecting the historical complexities of mollusk taxonomy.

Current classification:

• Kingdom: Animalia
• Phylum: Mollusca
• Class: Gastropoda
• Clade: Caenogastropoda
• Clade: Hypsogastropoda
• Clade: Neogastropoda
• Superfamily: Buccinoidea
• Family: Pisaniidae
• Genus: Monostiolum Dall, 1904
• Species: Monostiolum tessellatum (Reeve, 1844) [1]

Synonyms for Monostiolum tessellatum include [1]:

• Caducifer swifti (Tryon, 1881)
• Caducifer tessellatum (Reeve, 1844)
• Colubraria swifti (Tryon, 1881)
• Daphnella igniflua (Reeve, 1845)
• Fusus swifti (Tryon, 1881)
• Pisania igniflua (Reeve, 1845)
• Pleurotoma igniflua Reeve, 1845
• Pollia tessellatum (Reeve, 1844)
• Triton (Epidromus) swifti Tryon, 1881

The placement of this species within the Pisaniidae family (often considered a subfamily within Buccinidae, the true whelks, in older classifications) reflects ongoing molecular and morphological research in gastropod systematics [4]. The genus Monostiolum was established by William Healey Dall in 1904, with Triton swifti Tryon, 1881, as its type species, which is now considered a synonym of M. tessellatum [1, 4].

Distribution

This species occurs in the Caribbean Sea, the Gulf of Mexico and the Lesser Antilles.