Janthina janthina
(Linnaeus, 1758)
Description:
Dimensions range from 13.1 mm - 43.9 mm high and 17.3 mm - 46.5 mm wide.
Width to height ratio: 01.32:1 ~ 01.06:1
Shell: subglobose-turbinate, variable in shape from trochoid to globose, apex slightly depressed; lightweight, very fragile; small to medium. Exterior colour deep violet to blue-violet , whitish or blueish white near the apex, may have a broad pale band round the columella. About 4 whorls, somewhat rounded, blunt, with irregular weak axial growth lines, following curves of outer lip, and several spiral grooves, more prominent on base; protoconch apex glassy; teleoconch rounded, last whorl angled at periphery. Spire domed. Umbilicate: without or with narrow umbilical slit. Base almost straight to slightly convex. Columella straight, smooth, occasionally reflected and bent at the base. Aperture wide, forming about half an ellipse; outer lip thin, sharp, slightly sinuate centrally.
Distribution:
Worldwide, in tropical and temperate seas. Found in all Australian states, New Zealand, Kermadec Islands, Norfolk Island, Lord Howe Island [Beau,2017:190]; Massachusetts to Uruguay, Gulf of Mexico [Rosenberg et al., 2009: 642]; Mazatlan [Carpenter, 1857:185]]; Zanzibar to Cape of Good Hope and Wales [Reeve, 1858:2]; Saya de Malha Banks, Indian Ocean [Melvill, 1909:84]; All Brazilian coast to Uruguay [Rios, 1985:159]; Ecuador & Peru [Alamo & Valdivieso, 1997:29]; Yemen [Abubakr, 2004:69]; Clipperton Island [Kaiser, 2007:33]
Habitat:
pelagic; found washed up on ocean beaches
Etymology:
[latin] from ianthinus = violet coloured
Type Material:
Syntype: Janthina communis (synonym of J. fragilis renamed by Lamarck); 3 syntypes (only one likely original); NHMG-INVE41376 (formerly NHMG1094/79); no locality (Lamarck stated 'Atlantic Ocean and Mediterranean').
Lectotype/Neotype: Janthina penicephala (designated neotype to fix name usage); no type material in MNHN; near Cape of Good Hope.
Syntype: Janthina affinis; 3 syntypes; NHMUK1972018; no locality; ex Cuming collection.
Syntype: Janthina africana; 3 syntypes; NHMUK1976163; Zanzibar; ex Cuming collection.
Syntype: Janthina balteata; 3 syntypes; NHMUK1976164; Cape of Good Hope; ex Cuming collection.
Syntype: Janthina casta; 3 syntypes; NHMUK1972020; no locality; ex Cuming collection.
Syntype: Janthina caeruleata; 3 syntypes; NHMUK1976162; no locality; ex Cuming collection.
Syntype: Janthina depressa; 2 syntypes; NHMUK1976166; no locality; ex Cuming collection.
Syntype: Janthina fibula; 3 syntypes; NHMUK1976169; no locality; ex Cuming collection.
Syntype: Janthina grandis; 3 syntypes; NHMUK1972019; no locality; ex Cuming collection.
Syntype: Janthina involuta (distorted specimens of J. janthina); 3 syntypes; NHMUK1976165; no locality; ex Cuming collection.
Syntype: Janthina planispirata; 3 syntypes; NHMUK1951.3.14.1-3; Atlantic Ocean; ex Cuming collection.
Syntype: Janthina roseola; 3 syntypes; NHMUK1973003; Nicobar; ex Cuming collection.
Syntype: Janthina smithiae; 3 syntypes; NHMUK1976167; Glamorganshire, UK; ex Cuming collection.
Syntype: Janthina trochoidea; 2 syntypes; NHMUK20130060; no locality; V.W. MacAndrew collection (via G.B. Sowerby, likely ex Cuming).
Syntype: Iodes striulata (all considered J. janthina); 37 syntypes; NHMUK tablets 868-876 (9 tablets); no locality.
Syntype: Iodes striulata var. contorta; 2 syntypes (1 preserved), unusual folded columella; NHMUK tablet 877; no locality. for Janthina janthina (Linnaeus, 1758). [Beu, A. G., 2017]
Reeve, L. A. (1858). Plate I. Fig. 3b.
Distribution
as listed in source literature
Linnaeus, C (1758).
pp: 772.
Péron, F. &Freycinet, L. (1807).
Shown in text as Janthina penicephala F. Péron & Lesueur, 1807
Plate XXXI. Fig. 4.
Lamarck, J. B. P. A. de M. de (1816).
Plate 456. Fig. 1b.
Plate 456. Fig. 1a.
Adams, A. & Reeve, L. A. (1850a).
Shown in text as Ianthina planispirata A. Adams & Reeve, 1850
Plate XI. Fig. 10.
pp: 54.
Shell discoidal, with a depressed, plano-convex spire; whorls somewhat sharply rounded at the periphery; aperture rather broad, slightly sinuate anteriorly; deep violet in colour, paler toward the apex
Carpenter, P. P. (1857).
Shown in text as Ianthina striulata P. P. Carpenter, 1857
pp: 185-186.
Very similar to I. fragilis; with the nucleus not very obliquely placed; with four whorls, globose, with a flattened apex, and without sutures. The first whorls are beautifully adorned with sharp concentric ridges (lirulae), later showing lines of growth. Spiral lines are more or less distinct; with a distinct median angle. Upper side very pale, lower side violaceous. Columella extremely thin, bearing a sharp fold, more or less twisted at the base. Outer lip more or less sinuated, with an angular sinus. Inner lip scarcely projecting, extremely thin.
Reeve, L. A. (1858).
Shown in text as Ianthina caeruleata Reeve, 1858
Plate II. Fig. 7b.
Plate II. Fig. 7b.
Shell depressed-turbinate, with a small spire; whorls sloping-convex, obliquely and somewhat coarsely plicate-striate, densely and finely malleate-striate spirally; deep blue-violet, whitish towards the apex, with a broad pale band around the columella; columella nearly straight, closely reflexed; aperture transverse, sinuate at the middle
Reeve, L. A. (1858).
Shown in text as Ianthina smithiae Reeve, 1858
Plate III. Fig. 15b.
Plate III. Fig. 15a.
Shell depressed-ovate, with a short spire; whorls somewhat narrow, crosswise striated, scarcely angled; periphery of the last whorl violet, the spire and area around the columella whitish; columella slightly reflexed.
Reeve, L. A. (1858).
Shown in text as Ianthina casta Reeve, 1858
Plate I. Fig. 4b.
pp: 2.
Shell depressed-turbinate; whorls broadly sloping, then somewhat narrowly rounded, encircled throughout with fine impressed striae; purplish-violet, bluish-white toward the apex; columella arched, reflexed; aperture transverse, slightly sinuate in the middle
Plate I. Fig. 4a.
Reeve, L. A. (1858).
Shown in text as Ianthina involuta Reeve, 1858
Plate III. Fig. 12b.
Plate III. Fig. 12a.
Shell ovate-conic; whorls obliquely and somewhat coarsely striated, convex, the last whorl slightly involute near the aperture; upper surface violet-tinged white, opaque, lower surface bluish; with spiral grooves and paired striae; columella short; aperture suborbicular with a continuous margin.
Reeve, L. A. (1858).
Shown in text as Ianthina roseola Reeve, 1858
Plate I. Fig. 1b.
pp: 1.
Plate I. Fig. 1a.
Reeve, L. A. (1858).
Shown in text as Ianthina planispirata A. Adams & Reeve, 1850
Plate II. Fig. 9a.
Plate II. Fig. 9b.
Shell depressed; whorls sloping-convex, then somewhat sharply rounded, obliquely and coarsely plicate-striate; bluish-white, purplish-violet at the periphery; columella arched, somewhat dilated and reflexed; aperture transverse, sinuate in the middle.
Reeve, L. A. (1858).
Shown in text as Janthina fragilis Lamarck, 1801
Plate II. Fig. 6a.
Plate II. Fig. 6b.
Shell depressed-conical; whorls somewhat flat-sloping; with minute oblique and impressed spiral striae, decussated throughout; violet-whitish above, deep violet below; columella nearly straight
Reeve, L. A. (1858).
Shown in text as Ianthina depressa Reeve, 1858
Plate III. Fig. 14a.
Plate II. Fig. 14b.
Shell depressed-turbinate, with a short, flattened spire; whorls sloping and convex, obliquely folded and wrinkled, conspicuously grooved and striated spirally, with irregular, somewhat wavy striae; upper surface pale violet-white, somewhat opaque; underside semitransparent violet; columella twisted and pressed in; aperture transverse, scarcely notched
Reeve, L. A. (1858).
Shown in text as Ianthina grandis Reeve, 1858
Plate I. Fig. 3b.
Plate I. Fig. 3a.
pp: 2.
Shell subglobose-turbinate, with a slightly depressed apex; whorls swollen, rounded, sloping from the sutures, the last whorl descending gradually; obliquely striated, with a few flexuous grooves crossed spirally by fine lines; deep violet in colour, whitish near the apex; columella very finely recurved, then sinuously twisted
Reeve, L. A. (1858).
Shown in text as Ianthina balteata Reeve, 1858
Plate III. Fig. 11a.
Plate III. Fig. 11b.
Shell depressed-turbinate, with a small spire; whorls sloping-convex, concentrically folded and wrinkled, with spiral striations; upper surface violet-tinged white, underside blue, with a conspicuous white band around the columella; columella deep violet; aperture transverse, slightly sinuate in the middle
Reeve, L. A. (1858).
Shown in text as Ianthina affinis Reeve, 1858
Plate I. Fig. 2a.
Plate I. Fig. 2b.
pp: 1.
Reeve, L. A. (1858).
Shown in text as Ianthina africana Reeve, 1858
pp: 8b. Plate II.
Plate II. Fig. 8b.
Shell subglobose-turbinate, ventricose, with a somewhat blunt apex; whorls sloping-convex, then somewhat angulate, with superficial spiral grooves and striae; bluish-white above, purplish-violet below; columella reflexed, arcuately produced; lip moderately broadly sinuate.
Reeve, L. A. (1858).
Shown in text as Janthina communis Lamarck, 1822
Plate I. Fig. 5b.
Plate I. Fig. 1a.
pp: 2.
Shell depressed-semi-globose, flattened beneath; whorls sloping-convex, somewhat coarsely cross-striated; whitish above, purplish-violet below, whitish around the columella; columella somewhat twisted and reflexed; aperture transverse, slightly sinuate in the middle
Reeve, L. A. (1858).
Shown in text as Ianthina britannica Forbes & Hanley, 1852
Plate III. Fig. 13b.
Plate III. Fig. 113a.
Shell turbinated, somewhat ventricose; whorls coarsely cross-striated, sloping above, then rounded and slightly angled; deep purple-violet in colour, becoming paler toward the apex; columella straight; margin thinly reflected and twisted; aperture somewhat square, broadly notched in the middle.
Reeve, L. A. (1858).
Shown in text as Ianthina trochoidea Reeve, 1858
Plate II. Fig. 10a.
Plate II. Fig. 10b.
Shell pyramidally conical, somewhat solid; whorls sloping-convex, the last whorl angled, flattened-concave at the base, with crossed striations; sutures somewhat rough. Bluish-white overall, purplish-violet at the base; columella slightly reflexed and somewhat twisted; aperture sinuate at the angle.
Tryon, G.W. (1887).
Shown in text as Ianthina fragilis Lamarck, 1801, Ianthina planispirata A. Adams & Reeve, 1850, Ianthina britannica Forbes & Hanley, 1852, Janthina rotundata Dillwyn, 1840, Ianthina trochoidea Reeve, 1858
Plate 9. Fig. 94.
Plate 9. Fig. 99.
I. communis, Lam. (fig. 99)
Plate 9. Fig. 100.
Ianthina britannica Forbes & Hanley, 1852,
Macpherson, J.H. & Gabriel, C.J. (1962).
pp: 121. Fig. 145.
Wilson, B.R. (1993).
pp: 379. Fig. 36a-b.
Beechey, D. (2008).
pp: Janthina janthina. Fig. 2.
Putty Beach, Kilcare, NSW (C.362501)
pp: Janthina janthina. Fig. 1.
Putty Beach, Kilcare, NSW (C.362501)
Beu, A. G. (2017).
pp: 123. Plate 2. Fig. A.
Janthina janthina (Linnaeus)
GNS RM4442, two specimens, beach, Takou Bay, Northland, New Zealand
Alf, A., Brenzinger, B., Haszprunar, G., Schrödl, M. & Schwabe, E. (2020).
