''Brachytoma rufolineata'' is a
species of
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
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 Pseudomelatomidae
Pseudomelatomidae is a family of predatory sea snails, marine gastropods included in the superfamily Conoidea (previously Conacea) and part of the Neogastropoda ( Bouchet & Rocroi, 2005).
In 1995 Kantor elevated the subfamily Pseudomelatomina ...
.
Description
The length of the shell attains 16.5 mm, its diameter 5¾ mm.
(Original description) The strong shell is broadly fusiform It is yellowish, painted and spirally lineated with red-brown. It contains nine
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, of which about 2 form a smooth
protoconch
A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also called ...
. The post-nuclear whorls are convex, with an undulated suture, accompanied by a subsutural rib or keel, below this a slight excavation. The convexly rounded whorls have scarcely a tendency to be angular below the excavation The
sculpture consists of strong rounded ribs, crossing, though less distinctly, the excavation, 10 in number on the
body whorl
The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk.
In gastropods
In gastropods, the b ...
, where they nearly reach the base. There is one rib at some distance from the
peristome, just behind the upper sinus, especially strong and varix-like. The brown colour consists of. a faint tinge in the excavation. A similar zone exists below the periphery, much more conspicuous between the ribs, the principal lirae being nearly without exception red-brown, especially 4 of them on the body whorl. The spirals number from 3 to 7 on upper whorls and numerous ones on the body whorl and
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 ...
, which cannot be divided in principal and secondary ones. The excavation is finely spirally striated, moreover very fine growth-lirae are visible in many parts, if seen with a strong lens. The
aperture is elongately oval, with a broad, moderately deep sinus below the suture. The peristome is rather thin, with a very shallow sinus near the siphonal canal, which is short and broad. The columellar margin is tubercled above, then slightly concave, then straight and slightly directed to the left at the siphonal canal, strongly enamelled in its whole length. The interior of the aperture is light purplish, nearly white near the peristome.
Schepman, 1913. The prosobranchia of the Siboga expedition. Part IV -V - VI: Toxoglossa
Distribution
The marine species occurs off the Philippines and in the Sulu Archipel.
References
External links
*
Gastropods.com: ''Brachytoma rufolineata''
{{DEFAULTSORT:Brachytoma Rufolineata
rufolineata
Gastropods described in 1913