The Structure and Mode of Life of the Pyramidellidae, Parasitic Opisthobranchs

Fretter, Vera; Graham, Alastair G C

doi:10.1017/s0025315400023377

Cited by 95 publications

(70 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As a matter of convenience, therefore, it seems appropriate to leave the animal where it has long been placed, as the most primitive type of living opisthobranch. This work on Acteon, and recent work on Siphonaria (Hubendick, 1947), on the ellobiid pulmonates (Morton, 1954),on Onchidella (Fretter, 1946),on Omalogyraand Rissoella (Fretter, 1948),on the pyramidellids (Fretter & Graham, 1949)and on other tectibranchs (Lloyd, 1952), demonstrate, however, with great emphasis, how close the relationship of all the three major groups of gastropods is at some central point such as this. It seems likely that further research will show that it is from some archaeogastropod nucleus, represented to-day by such molluscs as the trochids, that all these groups have arisen.…”

Section: Discussionmentioning

confidence: 71%

Observations on the opisthobranch mollusc Acteon tornatilis (L.).

Fretter

Graham

1954

J. Mar. Biol. Ass.

View full text Add to dashboard Cite

SummaryActeon tornatilis is an opisthobranch mollusc which burrows in sand, using foot, labial and cephalic tentacles in the process. The last also help to exclude sand from the mantle cavity, which is extended into a caecum coiling alongside the visceral hump, presumably used for respiration but also for excretion. The main pallial water current is an exhalant one on the right.The mantle skirt carries, on the left, numerous repugnatorial glands with toxic secretions.Labial glands lie at the mouth and the buccal cavity contains jaws and a reduced buccal mass and radula. Into it open salivary glands the structure of which is like that of the pyramidellids. The oesophagus shows traces neither of glands nor of torsion whereas the stomach, though simplified, has resemblances to that of a prosobranch.The reproductive system is shown to be different from previous descriptions. Male and female ducts are separate from the lower end of the little hermaphrodite duct. The former passes to a prostate from which a vas deferens leads to a large uninvaginable penis; the latter has associated albumen and mucous glands and there is a receptaculum seminis to the duct of which a ventral channel leads from the female aperture in the mantle cavity.Discussion of these aspects of the animal's structure confirms its position as the most primitive of the opisthobranchs.

show abstract

Section: Discussionmentioning

confidence: 71%

Observations on the opisthobranch mollusc Acteon tornatilis (L.).

Fretter

Graham

1954

J. Mar. Biol. Ass.

View full text Add to dashboard Cite

show abstract

“…Only one species of mollusc appeared in the stomach contents more than occasionally; this was Odostomia plicata, which Fretter & Graham (1949) have shown to be probably ectoparasitic on Pomatoceros. These tiny gastropods were found chiefly in prawns trawled from near the Hoe.…”

Section: Notes On the Stomach Contentsmentioning

confidence: 96%

The biology of the common prawn,Leander serratusPennant

Forster

1951

J. Mar. Biol. Ass.

View full text Add to dashboard Cite

This work was undertaken at the suggestion of Mr F. S. Russell that little was known about the natural history of even so familiar a species as Leander serratus, the common prawn of the English Channel, which may at times form a valuable natural resource to the inshore fishermen. Attention was therefore chiefly concentrated on its growth rate and breeding biology. In spite of the long breeding season the statistical method of studying growth was adopted when preliminary results appeared successful. By this method additional data could be obtained on distribution and migration. In the closely related genus Crangon, growth has been shown to be retarded under laboratory conditions (Nouvel & van Rysselberge, 1937), so that an experimental study could not be relied on to give a picture of the normal life history. Höglund's recent monograph (1943) has treated Leander squilla in great detail. However, this species differs considerably in size and distribution from L. serratus, and it was felt that a similar study in the Plymouth area would not be mere repetition; in fact the biology of L. squilla itself differs somewhat in the two districts.

show abstract

“…Although not clear, it is probable that Kosuge was assuming that neogastropods had evolved from advanr~ed mesogastropods when he proposed the intermediate position for the heterogast!opods. Fretter and Graham (1949) put forward a cor.vincing, and now classic, argument for transferring the Pyramidellidae from the Prosobranchia to the Opisthobranchia, chiefly on head features, alimentary canal and reproductive habits. However, the specialised ectoparasitic mode of life of pyramidellids has caused numerous structural changes which make anatomical interpretations difficult.…”

Section: Discussionmentioning

confidence: 99%

The anatomy ofGegania valkyriepowell (Mollusca: Hetrogastropoda: Mathildidae) with notes on other heterogastropods

Climo¹

1975

Journal of the Royal Society of New Zealand

View full text Add to dashboard Cite

The animal of Gegania valkyrie Powell (Mathildidae) is described and compared with previous accounts of mathildid animal features. The acrembolic proboscis of Gegania valkyrie is compared with that of Architectonica reevei (Hanley) and Philip pia (Psilaxis) oxytropis A. Adams (Architectonicidae), and these three are compared briefly with ·that of Triphoridae. It is shown that, contrary to most accounts, Architectonica Reeding, Philippia Gray (s.s.) and Psilaxis Woodring all have a central tooth in the radula. The ·origin of the Heterogastropoda is discussed, ann it is suggested that the order is probably best placed in the Opisthobranchia.

show abstract

The Structure and Mode of Life of the Pyramidellidae, Parasitic Opisthobranchs

Cited by 95 publications

References 16 publications

Observations on the opisthobranch mollusc Acteon tornatilis (L.).

Observations on the opisthobranch mollusc Acteon tornatilis (L.).

The biology of the common prawn,Leander serratusPennant

The anatomy ofGegania valkyriepowell (Mollusca: Hetrogastropoda: Mathildidae) with notes on other heterogastropods

Contact Info

Product

Resources

About