Btarumot

Petaloconchus keenae

Classification:

Petaloconchus Keenae are gastropoda belonging to the subclass Caenogastropoda and the family vermitadae.

Distribution:

This species is common in intertidal and subtidal areas in Hawaiʻi and the tropical Pacific. It is found in the Central Pacific: Guam and Hawaii. This species is notorious because of its harmful effect on the growth, survival, and photophysiology of host corals.

Habitat:

The habitat of Petaloconchus sp. resembles that of P. keenae, which has been reported as an associate of the Indo-Pacific coral genera Porites, Montipora, and Pavona at the Hawaiian islands and possibly as Petaloconchuscf. keenae living in corals at Kwajalein Atoll in the Marshall Islands. It is therefore reasonable to speculate that the coral-associated Petaloconchus sp. in the southern Caribbean is the same species and that it has been introduced from the tropical Indo-Pacific.  

Description:

Petaloconchus keenae is a species of snails in the family worm-snails. The vermetidae are sessile gastropods distributed in tropical and subtropical seas (latitude 44 degree N-44 degree S), abundant in the intertidal zone and also in the subtidal zone. Petaloconchus is one of the five belonging genera that Vermitidae are known at present.  Petaloconchus keenae are typically coiled adult shells as seen on smooth surfaces and irregularly coiled adult shells. In the shell of Petaloconchus calcareous plates (spiral) laminate project and hang down from the upper wall of the tube, their function is unknown. The shell harbors in its anterior part of the relatively small soft body, which is able to retreat wholly in the shell.

Anatomy:

Adult vermetids are mostly welded to or embedded in solid substrate: rocks, stones, coral, shells. The adaptations for the sessile node of life are reflected in modifications of the shell, operculum, gill, methods of feeding a reproduction. The shell of vermetids are attached to the substrate by their apex. The apical whorls (2-4) are transparent, colorless, spirally coiled, they are the earliest one of the shell and constitute the protoconch which appears in the embryo and remains at the apex of the adult shell. In Petaloconchus the operculum is smaller than the aperture. Petaloconchus keenae can range the body length to 42mm and body volume can range to 6.56cm^3. They also have sexual reproduction.

Reproduction:

The sperm are enclosed in spermatophores produced within the male gonoduc. The vermetid spermatophores are oval to tear drop shaped that can range from less than 1 mm to 12.5 mm. They are liberated by the male into the sea water, dispersed by waves and currents and chance to reach females. When spermatophores are drifted by the inhalant current or caught in mucous feeding nets, they are brought to the mouth of the female.

Growth:

Vermetids are sessile, worm-like gastropods with irregular shell coiling and growth patterns, which live attached on hard substrata, usually in the intertidal zone or in the shallow subtidal zone of warm-temperate and tropical seashores.

Human use:

Although this species can’t be eaten, it is harmless to humans.

Cultural significance:

In Hawaiian costum, snails were the voice of the forest, they embodied the Polynesian oral tradition of passing on one’s genealogy through singing, making them extremely important to the cultural practices of hula and chant.