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Records of the Australian Museum (2017) Vol. 69 
other specimens. Traces of the axial ridgelets are visible on 
almost all specimens, but they are much better preserved 
on some than on others, and on well-preserved specimens 
from Kaawa Creek, southwest Auckland, New Zealand 
(Opoitian, Zanclean) and, in particular, on specimens from 
Grange Burn Formation (also Zanclean) at Muddy Creek, 
near Hamilton in western Victoria, Australia, quite high, 
thin lamellae are preserved. The protoconch has not been 
observed, despite careful searching of all available material. 
A supposed protoconch on the holotype of Eunaticina 
abyssalis (Simone, 2014: 586, figs 101—J) is actually the 
broken and corroded apex of the Janthina teleoconch (Fig. 
25G). The teleoconch of J. typica is thin, brittle and calcitic, 
apart from an interior white aragonitic layer, most obvious on 
the columella, and chalky in many specimens. Most freshly 
exposed specimens also have a distinctive pale brownish 
coloration, reflecting their calcitic composition. Because of 
the calcitic composition, even small, pale brown fragments 
of shell bearing axial ridgelets are diagnostic of Janthina 
in many Pliocene outcrops. Finlay (1931: 5) claimed that 
a few New Zealand specimens still showed “traces ... of 
the characteristic dark bluish-violet colour”, but the writer 
has not observed colour on any specimens, and other New 
Zealand paleontologists consulted also have not observed it. 
The diagnostic spiral folds are widest and most prominent 
at the periphery in most specimens, and grade into lower, 
narrower and more closely spaced ones on the sutural ramp 
and on the base, except for the wide one generated by the 
sinus, which on most specimens is almost twice as wide as 
one peripheral fold. 
Considerable variation is observed in most characters. The 
spire is significantly lower in small than in large specimens, 
as in Janthina chavani and J. janthina , although the weak 
allometrical growth in spire height observed in J. chavani is 
not obvious in J. typica. The two specimens observed from 
Santa Maria Island and the drawings published by Bronn 
(1861: pi. 19, fig. 3) and Mayer (1864a, b: pi. 6, fig. 41) 
show specimens that would not be surprising to find among 
samples collected in New Zealand or southern Australia. 
The six specimens observed from the material of Meco et 
al. (2015,2016) from La Esfinge, Gran Canaria Island (Figs 
25N, Q-R, T) are rather fragile, but most are well-preserved, 
with low to moderately high spires and relatively weak 
sculpture, but are not as weakly sculptured as the holotype 
of Eunaticina abyssalis (Simone, 2014) and provide a 
good basis for understanding the variation that might be 
expected in the Santa Maria Island population. The two 
smallest specimens from Gran Canaria are internal moulds, 
lacking shell. The total range of variation is no greater 
than is observed between widely separated populations of 
living Janthina species. Some consistent differences are 
observed between Australian and New Zealand collections, 
attributed solely to differences in preservation. Specimens 
from Grange Burn Formation (Kalimnan Australian Stage, 
Zanclean) at Muddy Creek and its tributary Grange Burn, 
near Hamilton, western Victoria, Australia (Figs 25A-C, 
L) are easily removed from weakly consolidated sediment 
and are much the best-preserved in the world. However, 
the material from La Esfinge, Gran Canaria Island, and the 
neotype of Hartungia typica are reasonably well-preserved. 
Almost all others observed have the axial ridgelets abraded to 
some extent, and most others are at least a little distorted— 
some dramatically so. Fine details are more consistently 
preserved in southern Australian than in New Zealand 
material, and most New Zealand specimens from localities 
other than Kaawa Creek are slightly to severely crushed. 
The few New Zealand Messinian specimens are all either 
very poorly preserved internal moulds of crushed shells 
or are very incomplete. Most Japanese specimens also are 
crushed and many are internal moulds only, although a few 
are excellently preserved (e.g., Tomida & Itoigawa, 1982: 
pi. 19, figs 1-3; Tomida & Kitao, 2002: fig. 2). Specimens 
from the Azores, Canary Islands, Japan, Australia and New 
Zealand are so similar that there is little doubt they are 
conspecific, displaying less variation than is observed in the 
living population of Janthina janthina. 
Chavan’s (1951: 135, fig. 1) pen drawing of the holotype 
of Acryhia (Hartungia) chouberti illustrated the sculpture 
diagrammatically. The identity of this specimen was resolved 
when Ludbrook (1978: pi. 12, figs 17-19) published 
photographs of Chavan’s holotype (Figs 24J-K, O) rather 
than of the poor plaster casts available previously, although 
the specimen has not been whitened before photography 
and focus is not ideal. The casts in MNHN and GNS are of 
a specimen with almost no sculpture, likely made from the 
paratype internal mould mentioned by Chavan rather than 
from the holotype. Ludbrook’s (1978: pi. 12, figs 17-19) 
illustrations reveal that the holotype has prominent spiral 
folds all over, including unusually prominent ones on the 
sutural ramp, and falls within the range of variation of 
Janthina typica. Ludbrook (1978: 121) cautiously concluded 
that “while there may be good reason to suspect that the 
Australian and New Zealand material is identifiable at 
the species level with the Azores Hartungia typica and its 
synonym Janthina hartungi”, she thought that could not be 
confirmed because of the lack of authentic Azores material 
for comparison. Now that this has been resolved, the writer 
sees no reason to doubt that fossil Janthina species had the 
same cosmopolitan geographical ranges as living Janthina 
species, and that Heligmope dennanti, “Turbo” postulatus, 
Acrybia chouberti , Hartungia elegans and Eunaticina 
abyssalis are all synonyms of Janthina typica. 
It is unfortunate not to retain Georg Hartung’s name. He 
collected the fossils described by Bronn (1861) and some 
of those described by Mayer (1864a, b). Pinto & Bouheiry 
(2007) provided an account of Hartung’s research in the 
Azores, Madeira and Canary Islands and his extensive 
collaboration with Charles Lyell. 
Time range. Messinian-early Piacenzian (latest Miocene- 
early late Pliocene); c. 7-3.0 Ma, to judge from its range in 
New Zealand (Kapitean-Waipipian Stages; Messinian-early 
Piacenzian; Cooper, 2004: fig. 13.1). This time range is 
confirmed less precisely in Japan and southern Australia. 
