''Pteropurpura festiva'', commonly known as the festive murex, is a species of predatory

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

, a

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk in the family Muricidae, the rock snails. Native to the Eastern Pacific, these sea snails grow to 34–67 mm in length. MolluscaBase (2019). MolluscaBase. Pteropurpura festiva (Hinds, 1844). Accessed through: World Register of Marine Species at: http://marinespecies.org/aphia.php?p=taxdetails&id=743644 on 2019-11-19 This species was previously known as ''Murex festivus''. Because the shell of this sea snail is attractive, and is common in San Diego, the name '' The Festivus'' was used for the San Diego Shell Club publication, which was started in 1970, became a science journal on

malacology Malacology is the branch of invertebrate zoology that deals with the study of the Mollusca (mollusks or molluscs), the second-largest phylum of animals in terms of described species after the arthropods. Mollusks include snails and slugs, clams, ...

, and as of 2021 has been published for over 50 years.

Description

The length of the shell varies between 20 mm and 67 mm. The elongately ovate shell contains six convex

whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane floral ...

s with three low, reflexed varices per whorl. These varices are finely frilled on front. Between these varices, a rib shows a large, blunt knob on the shoulder. The wide outer lip is finely dentate with 5-7 teeth inside. The columella is simple and smooth. The oval aperture shows a varix extenting to the short, deep and recurved

siphonal canal The siphonal canal is an anatomical feature of the shells of certain groups of sea snails within the clade Neogastropoda. Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water is ...

. The ground color of the shell varies from white to light brown, crossed by evenly spaced, thin, incised, spiral dark brown lines It is a formidable predator on

mussel Mussel () is the common name used for members of several families of bivalve molluscs, from saltwater and Freshwater bivalve, freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other ...

limpet Limpets are a group of aquatic snails that exhibit a conical shell shape (patelliform) and a strong, muscular foot. Limpets are members of the class Gastropoda, but are polyphyletic, meaning the various groups called "limpets" descended indep ...

barnacle A barnacle is a type of arthropod constituting the subclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in eros ...

s and other snails. But through this biotic characteristic, it is responsible for resistance to the Asian mussel (''

Musculista senhousia : ''For the Asian green mussel, see Perna viridis.'' ''Arcuatula senhousia'', commonly known as the Asian date mussel, Asian mussel or bag mussel, is a small saltwater mussel, a marine bivalve mollusk species in the family Mytilidae, the musse ...

'') invasion in Southern California. Cheng, Brian S., and Kevin A. Hovel. "Biotic resistance to invasion along an estuarine gradient." Oecologia 164.4 (2010): 1049-1059
/ref>

Distribution

This marine species occurs abundantly in the

intertidal zone The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species o ...

and mud flats off Southern California, USA (with most records from Santa Barbara, Los Angeles and San Diego) to Baja California, Mexico

References

* Hinds, Richard Brinsley. The Zoology of the Voyage of HMS Sulphur: Under the Command of Captain Sir Edward Belcher During the Years 1836-42. Vol. 3. Smith, Elder, 1844. * J. Hertz & C. M. Hertz, 2006. ''The Festivus, the making of a scientific journal'' The Festivus 38(5): 53-57 * D’Attilio, A. & B. Myers 1983. ''The genus Pteropurpura Joussemme, 1880 (Muricidae: Ocenebrinae).'' The Festivus XV(ll): 111-112. * Tuskes P. & Tuskes A. (2016). ''Native Pteropurpura of the eastern Pacific (Muricidae).'' The Festivus. 48(4): 211-220 * Morris, H. Robert, Donald P. Abbott & Eugene C. Haderlie 1990. I''ntertidal Invertebrates of California.'' Stanford University Press, Stanford, CA. Chapter 1 3 Prosobranchia: Marine Snails. Pp. 230-307. * Tuskes, Paul M. & Ann Tuskes 2009. ''Influence of Habitat on Growth and Prey Selection of Pteropurpura festiva, the Festive Murex.'' The Festivus. 41(3): 25-29.

External links

* {{Taxonbar, from=Q3140165 Muricidae Gastropods described in 1844