potamididae d - fisheries · potamididae potamididae swamp-ceriths and horn shells diagnostic...

Potamididae POTAMIDIDAE

Swamp-ceriths and horn shells

Diagnostic characters: Shell thick andsolid, tapering, high-conical, with many

flattened or slightly convex spire whorls.Sculpture generally coarse, wi th spi ralgrooves or cords and often axial ribs, giving areticulated to nodular aspect. Axial varicessometimes present. Periostracum usually welldeveloped, brownish to corneous. Aperturerelatively small, with a short and deep ante-rior siphonal canal. Outer lip often thickenedand more or less flaring. Operculum rounded,corneous, with many spiral coils and a sub-central nucleus. Head with a pair of tentacles,abruptly narrowing distally and bearing eyes ator above their thickened bases. Foot rounded infront and obtuse behind.Habitat, biology, and fisheries: Abundant inbrackish-water environments, on mud flats ofestuaries and in mangrove swamps near hightide line. Feeds on algae or detritus, which arescraped with a powerful radula.Sexes separate.Males devoid of penis, sperm transferred duringmating in spermatophores. Potamididae are ex-tensively used as food in the area, and theirshell is mainly utilized for making lime. In thePhilippines, they appear quite often in localmarkets. They are consumed steamed orboiled, and a somewhat piquant taste increasesthe desire for drinking.

Similar families occurring in the areaCerithiidae: shell very similar, but easily distinguished by the ovateoperculum with only a few spiral coils.

Key to species of interest to fisheries occurring in the area1a. Shell with both axial and spiral sculpture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . → 21b. Shell with spiral sculpture only (Fig. 1) . . . . . . . . . . . . . . . . . . .Telescopium telescopium

2a. Columella with 2 spiralridges internally (notalways visible from theoutside) . . . . . . . . . . . . . → 3

2b. Columella without spi-ral ridges . . . . . . . . . . . . → 4

3a. Shell small (up to 6 cmin length); anterior endof outer lip expandedover the siphonal ca-nal (Fig. 2) . . . Terebralia sulcata

3b. She l l la rge (up to19 cm in length); ante-rior end of outer lip notexpanded over the si-phonal canal (Fig. 3). . . . . . . . . Terebralia palustris

paucispiral operculum

Cerithiidae

ventral view

multispiraloperculum

siphonalcanal

expandedouter lip

manywhorled

spire

(ventral view)

Fig. 1 Telescopiumtelescopium

(ventral view)

Fig. 2 Terebraliasulcata

(ventral view)

Fig. 3 Terebraliapalustris

448 Gastropods

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4a. Outer lip posteriorly expanded in a flaring, wing-like process (Fig. 4) . . . . . .Cerithidea cingulata4b. Outer lip not expanded posteriorly in a flaring, wing-like process . . . . . . . . . . . . . . . . . → 5

5a. Periphery of last whorl angular (Fig. 5) . . . . . . . . . . . . . . . . . . . . . .Cerithidea quadrata5b. Periphery of last whorl rounded (Fig. 6) . . . . . . . . . . . . . . . . . . . . . . . Cerithidea obtusa

List of species of interest to fisheries occurring in the areaThe symbol� is given when species accounts are included.

� Cerithidea cingulata (Gmelin, 1791)� Cerithidea obtusa (Lamarck,1822)� Cerithidea quadrata Sowerby, 1866

� Telescopium telescopium (Linnaeus, 1758)

� Terebralia palustris (Linnaeus, 1767)� Terebralia sulcata (Born, 1778)

ReferencesBrandt, R. 1974. The non-marine aquatic mollusca of Thailand. Arch. Moll., 105:1-423.Houbrick, R.S. 1991. Systematic review and functional morphology of the mangrove snails Terebralia and Telescopium

(Potamididae: Prosobranchia). Malacologia, 33(1-2):299-338.Van Benthem Jutting, W.S.S. 1956. Systematic studies on the non-marine mollusca of the Indo-Australian Archipelago.

V. Critical revision of the javanese freshwater gastropods. Treubia, 23(2):259-477.

posteriorlyflaring

outer lip

Fig. 4 Cerithidea cingulata(ventral view)

Fig. 5 Cerithidea quadrata(ventral view)

Fig. 6 Cerithidea obtusa(ventral view)

Potamididae 449

Cerithidea obtusa (Lamarck, 1822)

Frequent synonyms / misidentifications: Potamides obtusus (Lamarck, 1822) / None.FAO names: En - Obtuse horn shell; Fr - Potamide obtus.Diagnostic characters: Shell medium sized, with amoderately high conical spire and broad roundedbase. Spire whorls convex, with moderately deep su-ture, 6 or 7 rounded spiral cords crossed by stronger,relatively broad axial ridges, and forming a pattern ofmore or less sharp nodules. Apical part of the spirealways broken off. Body whorl wide, rounded at periph-ery, with the axial ridges fading away and with 12 to 15fine spiral cords on the base. An indistinct axial varixsometimes present on left ventral side of body whorl.Aperture wide, subcircular in outline, without a wing-likeexpansion at posterior end. Outer lip thickened andflaring, with a tongue-shaped anterior end produced overthe siphonal canal. Columella narrow, posteriorly inter-rupted, without internal spiral ridges. Anterior siphonalcanal short, open and oblique. Colour: outside of shellbrown or dull purplish brown, with a brighter zone justbelow the suture; base plain brown or yellowish with adarker brown zone. Aperture brownish, outer lip ofmature specimens cream.Size: Maximum shell length 6 cm, commonly to 5 cm.Habitat, biology, and fisheries: Common in mangroveswamps, on roots and branches above the substrate, oron mud tidal banks. Animals often concentrate in thewettest spots, when the mud bottom is partly dry at lowtide. This species serves commonly as food in SoutheastAsia and Indonesia.Distribution: Indo-WestPacific, from Madagascar andIndia to eastern Indonesia;north to the Philippines andsouth to northern Queens-land.

ventral view

(after Van Benthem Jutting, 1956)

450 Gastropods

Telescopium telescopium (Linnaeus, 1758)

Frequent synonyms / misidentifications: Potamides telescopium (Linnaeus, 1758); ? Telescopiummauritsi Butot, 1954 / None.FAO names: En - Telescope snail; Fr - Potamide télescope.Diagnostic characters: Shell large, with a highconical spire and a broad, rather flat base. Axialsculpture reduced to growth marks. Spire whorlsflat sided, with weakly defined suture, 3 large,flat-topped spiral cords and a narrower one, alter-nate with deep spiral grooves. Spiral cords some-times disappearing with age or erosion. Body whorlangulate to strongly rounded on periphery, with spi-ral cords on the base and a deep spiral groovearound the columella. Aperture obliquely quadran-gular, relatively small. Outer lip not flared, thin andnearly smooth, its lateral margin concave with re-spect to direction of growth. Columella twisted, witha strong, central spiral ridge. Anterior siphonalcanal very short, open and strongly twisted. Col-our: outside of shell dark reddish brown to almostblack, often with a paler spiral band near the suture.Interior similarly coloured, with a light brown orwhitish columella.Size: Maximum shell length 13 cm, commonly to11 cm.Habitat, biology, and fisheries: Abundant in man-grove areas and on intertidal mud flats, where thewater is salt or highly brackish. Often partly buriedin mud, with only top of spire projecting.Used as foodin certain areas of Southeast Asia. Frequently ap-pearing in local markets of Thailand, Indonesia andthe Philippines.Distribution: Indo-WestPacific, from Madagascar,Réunion Island, India and SriLanka, to Papua New Guinea;north to the Philippines andsouth to central Queensland.

ventral view


Potamididae 451

Terebralia palustris (Linnaeus, 1767)

Frequent synonyms / misidentifications: Potamides palustris (Linnaeus, 1767); Pyrazus palustris(Linnaeus, 1767) / None.FAO names: En - Mud creeper; Fr - Potamide des marais.Diagnostic characters: Shell large, elongate-fusiformwith a rounded base. Spire whorls flat sided, withdeep, narrow suture, 4 equal-sized, flattened spiralribs alternate with deep, narrow spiral grooves and over-lain by broad axial ridges, producing a pattern of weak,squared nodules. Body whorl wide, regularly rounded,with numerous, slightly beaded spiral cords on the base,and a thick axial varix on its left side. Earlier varicesrandomly distributed along the spire. Aperture ovate,grooved inside. Outer lip somewhat thickened andflared, not expanded over the anterior siphonal canal.Columella calloused, with 2 spiral ridges internally(not visible from the outside in full grown specimens withintact outer lip). Anterior siphonal canal short, open,inclined toward the left. Colour: outside of shell darkbrown to bluish black, sometimes with lighter spiralbands or indistinct axial flames. Aperture glossy, black-ish brown with light tan columella.Size: Maximum shell length 19 cm, commonly to 12 cm.Habitat, biology, and fisheries: Abundant and con-spicuous in the mud of mangroves, and more generally,in brackish-water coastal areas of the Indo-West Pa-cific. Extensively collected for food in many places of itsdistribution.Distribution: I n d o - We s tPacific, from East Africa, in-cluding Madagascar and theRed Sea, to Melanesia; northto the Philippines and south tosouthern Queensland andNew Caledonia.

ventral view


452 Gastropods

Terebralia sulcata (Born, 1778)

Frequent synonyms / misidentifications: Pyrazus sulcatus (Born, 1778) / None.FAO names: En - Sulcate swamp cerith; Fr - Potamide sillonné.Diagnostic characters: Shell medium sized, elongate-fusi-form with a rounded base. Spire whorls weakly inflated, withdeeply incised suture, 4 or 5 spiral cords alternate with deepspiral grooves and overlain by numerous axial ridges, forminga pattern of squared nodules. Body whorl wide, regularlyrounded, with numerous beaded spiral cords on the base, and athick axial varix on its left side. Earlier varices randomly distrib-uted. Outer lip of the aperture thickened and widely flared,smooth to slightly crenulated, expanded anteriorly to the baseof columella over the short, tubular siphonal canal. Columellaglazed, with 2 spiral ridges anteriorly (hardly visible from theoutside in full grown specimens with intact outer lip). Colour:outside of shell light to dark brown, with paler axial varicesand sometimes with spiral banding. Aperture shiny brown tocream.Size: Maximum shell length 6.5 cm, commonly to 5 cm.Habitat, biology, and fisheries: On mud flats in estuaries andmangrove areas, often on stems and roots of the trees. Exten-sively used as food and lime material in the Philippines.Distribution: Indo-West Pacific, from Madagascar to Melanesia;north to Japan and south to southern Queensland and NewCaledonia.

ventral view


Potamididae 453

Cerithidea cingulata (Gmelin, 1791)

Frequent synonyms / misidentifications: Potamides cingulatus (Gmelin, 1791); Tympanotonos fluviatilis (Potiez andMichaud, 1838) / None.

En - Girdled horn shell; Fr - Potamide sanglé.Maximum shell length 4.5 cm, commonly to 3.5 cm. Abundant on mud flats near mangroves and inbrackish or supersalted fishponds. Locally, numbers of about 500 individuals per square meter canoccur. Usually living in the upper bottom layer of mud which is almost liquid. Extensively collectedfor food and to make lime in the Philippines. Indo-West Pacific, from India and Sri Lanka to PapuaNew Guinea; north to Japan and south to central Queensland.

Cerithidea quadrata Sowerby, 1866

Frequent synonyms / misidentifications: Potamides quadratus (Sowerby, 1866) / Cerithidea obtusa (Lamarck, 1822);C. rhizophorarum A. Adams, 1855.

En - Quadrate horn shell; Fr - Potamide équarri.Maximum shell length 5.5 cm, commonly to 4.5 cm. In mangrove areas and brackish fishponds.Often climbing up the trees to feed on algae growing at the roots and stems. Commonly foundtogether with Cerithidea obtusa. Collected for food in many areas of Southeast Asia. Eastern partof the Indian Ocean and the tropical West Pacific, from the Andaman Sea to eastern Indonesia;north to Viet Nam and the Philippines, and south to southern Indonesia.

ventral view

anterior 1/3 of shell(lateral view)


ventral view


454 Gastropods

Turritellidae TURRITELLIDAE

Turret shells

Diagnostic characters: Shell elongate, sharply conical, withnumerous whorls and a small, square to rounded aperture.

Umbilicus usually absent. Whorls strongly sculptured with spiral ribsor keels. Growth lines arched to sinuous. Outer lip of the aperture thin,often concave. Inner lip smooth. Anterior siphonal canal absent.Operculum corneous, rounded, with many spiral coils and a centralnucleus; border of the operculum very thin, often with flexible bristles.Head large and prominent, with a short snout and long, taperingtentacles bearing eyes on slight swellings at their outer bases. Footrather short, truncate anteriorly, obtusely attenuated posteriorly andgrooved beneath.Habitat, biology, and fisheries: Filter-feeding, mostly living in soft,subtidal bottoms of sand or mud. Organic particles are drawn throughthe mantle cavity by means of ciliary water currents, sorted by smalltentacles and the tiny bristles of the operculum, trapped in mucoussheets on the gills and transferred to the mouth. Sexes separate,fertilization internal. Eggs generally laid in a cluster of spherical, stalkedcapsules, attached to stones. A short, planktonic larval stage is usuallypresent, but some species brood their eggs and embryos to the crawl-ing stage. In the area, Turritellidae are collected occasionally for food,but mainly for their shells that are used in the shellcraft industries tomake decorative items.

Similar families occurring in the areaTerebridae: general shape of shell similar to Turritellidae, but with awell-marked, notched siphonal canal at the anterior end; operculumovate, with a terminal nucleus.

Key to species of interest to fisheries occurring in the area1a. Sides of the whorls sharply keeled . . . . . Turritella duplicata1b. Sides of the whorls rounded, not keeled . . . Turritella terebra


� Turritella duplicata (Linnaeus, 1758)� Turritella terebra (Linnaeus, 1758)

ReferencesGarrard, T.A. 1972. A revision of Australian recent and tertiary Turritellidae. J. Malac. Soc. Aust., 2:267-337.Marwick, J. 1957. Generic revision of the Turritellidae. Proc. Malac. Soc. Lond., 32:144-166.

ventral view

many-whorled

spine

ventral view

siphonalcanal

Terebridae

Turritellidae 455

Turritella terebra (Linnaeus, 1758)

Frequent synonyms / misidentifications: None / None.FAO names: En - Screw turret; Fr - Turritelle vis.Diagnostic characters: Shell large and solid, with anextremely long and tapering spire, with 25 or more whorlsin mature specimens. Whorls strongly convex in outline,with impressed suture and up to 6 prominent spiral cordsand weaker interstitial spiral threads. Apical end of spireinvariably missing in adult shells. Aperture almost circularin outline. Margin of outer lip rather thin, forming a broad,very shallow sinus leaning backward with respect to direc-tion of growth, continued as a straight line across the base(on specimens with a broken aperture, shape of the outer lipretained in the axial growth marks of body whorl). Colour:shell light to dark brown externally and internally.Size: Maximum shell length 17 cm, commonly to 15 cm.Habitat, biology, and fisheries: On soft bottoms, fromshallow sublittoral zones to a depth of about 30 m. Regularlycollected and marketed in the northern Philippines.Distribution: Widespread in the Indo-West Pacific, fromEast Africa, including the Red Sea, to Melanesia; north toTaiwan Province of China and south to central Queensland.

ventral view

(after Dance, 1993)

456 Gastropods

Turritella duplicata (Linnaeus, 1758)

Frequent synonyms / misidentifications: Turritella acutangula (Linnaeus, 1758); Zaria duplicata (Linnaeus, 1758) /None.

En - Duplicate turret; Fr - Turritelle anguleuse.Maximum shell length 18 cm, commonly to 15 cm. On subtidal sand and mud bottoms. Collectedwhere common, in the Southeast Asian region. Indo-West Pacific, from Madagascar to Indonesia;north to the Philippines and south to northern Queensland.

ventral view

(after Short and Potter, 1987)

Turritellidae 457

Vermetidae VERMETIDAE

Worm shells

Diagnostic characters: Shell long, usually irregularly coiled or even disjunct and resembling aworm tube, but composed of 3 layers, with the inner one porcelaneous. Shell permanently attached

to a hard substrate. First whorls coiled around an axis at a 90° angle to that of the larval shell. Sculptureweak, longitudinal or transverse, and irregular.Aperture rounded, sharp-edged, without a siphonal canal.Operculum horny, spiral, sometimes absent. Head with short tentacles bearing eyes at their outer bases.Foot small.

Habitat, biology, and fisheries: Mostly in warm-temperate or tropical, intertidal, and shallow waterenvironments. Attached to rocks, corals and other shells, sometimes corroding the substrate and partly oreven completely embedded in it. Some species occur in dense masses and may be important contributorsto reef-building. Filter-feeding animals, extracting tiny planktonic organisms or detrital fragments from thewater by means of 2 different ways of capture. In the ciliary feeding method, food is swept in the mantlecavity with the incurrent water, caught on the gill filaments, wrapped in mucous and carried along ciliarytracts to the mouth. In the mucous feeding method, a secretory gland of the foot produces sticky mucousstrings or nets that are released in the water to entangle the food, then drawn back and swallowed. Sexesseparate, fertilization internal, presumably by means of water-borne sperm. Eggs brooded by the female,hatching as crawling juveniles, or as free-swimming larvae for a short planktonic stage. Worm shells aretraditionally used as food by some coastal populations of the area, notably in Polynesia. Though they maybe regularly collected, they generally appear in markets only rarely.Remarks: The taxonomy of the Vermetidae remains poorly known, at least at the species level. The larvaland first stages of the juvenile shell can be essential in identification, but are usually lost in adult specimens.However, newly settled shells frequently occur among the latter.

Similar families occurring in the areaSerpulidae: sedentary Polychaetes building a tube open at both ends, or without an initial spiral coiling,and composed of only 2 layers (the inner one not porcelaneous).Siliquariidae: shell tubular, loosely coiled in the later stages, with a row of tiny holes or a slit along one side;usually embedded in sponges.

apical region of shell (enlarged)

1st post-embryonic

whorlembryonic

shell

apical regionexternal view of shell

aperture

longitudinal slit

outside of shell

Siliquariidae

posterior end

outside of tube

anterioropening

Serpulidae

458 Gastropods

Key to species of interest to fisheries occurring in the area1a. Shell corroding a trench in the substrate; operculum present, filling the aperture of tube

(Fig. 1a, b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Dendropoma maximum1b. Shell not corroding the substrate; operculum absent . . . . . . . . . . . . . . . . . . . . . . . → 2

2a. Shell rather short (reaching 5 cm in length), with the entire coil in contact with thesubstrate; outer colour blackish brown (Fig. 2) . . . . . . . . . . . . . . . . .Serpulorbis colubrinus

2b. Shell rather long (reaching 11 cm in length), with only the initial stages of growth incontact with the substrate; outer colour yellowish white with reddish brown spiral lines(Fig. 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Serpulorbis medusae


� Dendropoma maximum (Sowerby, 1825)

� Serpulorbis colubrinus (Röding, 1798)� Serpulorbis medusae (Pilsbry, 1891)

ReferencesKeen, A.M. 1961. A proposed reclassification of the gastropod family Vermetidae. Bull. Br. Mus. Nat. Hist. (Zool.),

7(3):183-213.Morton, J.E. 1965. Form and function in the evolution of the Vermetidae. Bull. Br. Mus. nat. Hist. (Zool.), 11(9):585-630.

aperture

a) mature shell b) operculum

Fig. 1 Dendropoma maximum(lateral view)

Fig. 2 Serpulorbis colubrinus(external view)

Fig. 3 Serpulorbis medusae(external view)

Vermetidae 459

Dendropoma maximum (Sowerby, 1825)

Frequent synonyms / misidentifications: Siphonium maximum (Sowerby, 1825); Vermetus maximusSowerby, 1825 / Vermetus novaehollandiae Chenu, 1843.FAO names: En - Great worm shell; Fr - Grand vermet.

Diagnostic characters: Shell large, solid, tubular, irregularly coiled, often straight or only slightlycurved in the adult, partly embedded in the substrate. Sculpture variable, with weak lamellar transversethreads. Operculum well developed, as large as the aperture, smooth and concave externally, its innersurface with a distinct, slightly thickened central scar for attachment to the foot. Body of the animal thickand cylindrical, about the diameter of a man’s small finger in the average adult specimens, with a short,blunt-tipped and only slightly arched visceral mass. Colour: outside of shell whitish to pale brown,sometimes stained brown; interior glossy white. Operculum translucent golden brown. Head and exposedparts of the foot elegantly pigmented in bluish black and light brown. Exposed margins of the mantle witha wide bluish black band.Size: Maximum shell length 45 cm, commonly to 10 cm.Habitat, biology, and fisheries: Abundant on the outer parts of coral reefs, partly imbedded among corals.Ciliary feeding species. Traditionally collected for food in eastern Polynesia.Distribution: Islands of thetropical West Pacific, from In-donesia to eastern Polynesia;north to the Philippines andsouth to the Great BarrierReef, eastern Queensland.

external view of mature shell

(after J.E. Morton, 1965)

operculum

external view

lateral view

460 Gastropods

Serpulorbis colubrinus (Röding, 1798)

Frequent synonyms / misidentifications: Cladopoda colubrina (Röding, 1798); Vermetus ater Chenu, 1843; V. colubrinus(Röding, 1798) / None.

En - Snake-like worm shell; Fr - Vermet serpentin.Maximum shell length 5 cm, commonly to 3.5 cm. Common on rocky substrates. Intertidal andshallow subtidal zones. Mucous-feeding species. Occasionally collected by native populations inthe tropical Pacific. Distribution imperfectly known. Thought to be widespread in the Indo-WestPacific; most common in the central part of that area.

Serpulorbis medusae (Pilsbry, 1891)

Frequent synonyms / misidentifications: Thylacodes medusae Pilsbry, 1891; Vermetus medusae (Pilsbry, 1891) / None.

En - Jellyfish worm shell; Fr - Vermet méduse.Maximum shell length 11 cm, commonly to 8 cm. Common on hard substrates. Intertidal and shallowsubtidal waters. Mucous-feeding species. Occasionally collected for subsistence. Limited to thewestern Pacific, from Indonesia to the Philippines and Japan.

external view of shell

(after Sprinsteen and Leobrera, 1986)

external view of shell

(after Springsteen and Leobrera, 1986)

Vermetidae 461

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