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the often extensive intraspecific variation). In effect, a geographically restricted species, limited to Sicilian wa-
link between the markedly keeled and inflated shells
(e.g. A. carinata), and the more typical Alvania-shape
taxa could be hypothesized. It could be articulated and
summarized in the transition A. carinata-A. lactea (via A. about this species is not encouraging: I just know that:
francescoi new species-A. rosariae new species) to more
typical Alvania secies. A parallel trend could be con-
structed: A. tenera and A. cingulata, showing a progres-
sive weakening of the spiral sculpture, the proportional
reduction in the expansion of the body whorl and the
formation of the outer lip thickening. Furthermore,
other interspecific trends, involving various nominal
groups of Alvania, could be constructed when consider-
ing the widely variable shells of most of the species dis-
cussed here. Nowstanding this, I cannot deny that all
these hypothetical links appears tenuous and that these
taxa, sharing a quite inflated and well-expanded body
whorls, a wide, internally smooth aperture, seem some-
what distant from Alvania sensu stricto This point of view Pliocene and the Miocene of Mediterranean basin, re-
could lead to regard them as belonging to an inclusive
taxonomic group (preferably at subgeneric level). Galeo-
dina could serve as the appropriate taxonomic unit. Nev-
ertheless, since I believe that appropriate anatomical
studies (of which there is no exhaustive data-set) should
be used to solve this question, I have preferred a more
open-ended option, placing the discussed species here,
from carinata to tenera, in Alvania sensu lato
The re-analysis of the Neogene-Recent R. tiberiana,
type species of Galeodinopsis, has lead me to reevaluate
the latter taxon as the appropriate genus for grouping
species characterized by a particular teleoconch micro-
sculpture (consisting of very fine spiral threads, formed
by roughly prismatic elements, extending perpendicu-
larly respect from the shell surface, plus the pitted sur- species level, being characterized by sculptural patterns
face on the primary spiral cords, as seen in Manzonia)
and by having a conical Alvania-like shell shape. The
oldest representative of this genus is the European upper
Oligocene R. duboisi. The upper Oligocene M. forami-
nata and M. moulinsi are probably more linked to Man-
zonia sensu lato than to Galeodinopsis while the Recent
Macaronesian M. spreta could be doubtfully regarded as
belonging to Galeodinopsis.
Because of its affinity with Alvania, Galeodinopsis
probably derived from some Oligocene group of that
taxon and could be regarded as a transitional link to
Manzonia. It is interesting that, as indicated by Lozouet
(1998), the genus Alvania had a surprising radiation in
the upper Oligocene, creating a strong diversification.
Furthermore, the Manzonia sensu stricto species, char-
acterized by the quite slender shell with strongly opis-
thocline ribs and very marked spiral cords on the shell
base, seem to be well-established from the European
Neogene, where they are represented by the following
species: M. crassa, M. falunica, M. pontileviensis, and M. toconch II (also observed in G. tiberiana), consisting of
scalaris.
All the discussed species have a multispiral proto-
conch, indicating a planktotrophic larval development,
with the exception of A. cingulata, which is the most
THE NAUTILUS, Vol. 122, No. 1
ters. The reason for its very limited geographical distri-
bution is not certainly solely attributable to its non-
planktotrophic larval development. Our knowledge
● There is no known fossil record . . . is it a very recent
Mediterranean acquisition?
● From a large amount of bulk samples (about 50 liters
from Magnisi and 20 liters from Mondello), I picked
only a single eroded shell! . . . Is it still a living species?
Among species with planktotrophic development dis-
cussed in this report, three show an eastern Atlantic-
Mediterranean distribution: A. carinata, A. lactea, and
A. tenera. Among these, the first two species have a Neo-
gene to Recent distribution, being known from the
spectively, and show a quite extensive east Atlantic dis-
tribution, being commonly recorded from the English
Channel to Morocco. Regarding the third species, living
in Mediterranean and along the Atlantic Morocco and
the Canary Islands coasts, I did not find any Mediterra-
nean or Atlantic fossil records. The extinct species A.
francescoi, A. prusi, and A. rosariae are limited to the
Mediterranean Pleistocene, while Galeodinopsis tiberi-
ana has a Miocene-Pliocene Mediterranean distribution
and lives along the W African coasts from Mauritania to
northern Angola.
In general, the protoconchs of the species reported
here do not indicate any distinguishing taxonomical char-
acters at the supraspecific, and, in most cases, at the
shown by several rissoid species. Among the plank-
totrophic species, the commonest sculptural pattern on
protoconch I (observed in A. carinata, A. francescoi, A.
lactea, A. rosariae, and A. tenera), consisting of fine spiral
lirae and scarce to abundant pimples between them, is
shown by A. cancellata (Da Costa, 1778) (see Giannuzzi-
Savelli et al., 1996, fig. 408b), A. beani (Hanley in
Thorpe, 1844) (see Giannuzzi-Savelli et al., 1996, fig.
412), A. cimex (Linneus, 1758) (see Ponder, 1985,
figs.86C–B), A. cimicoides (Forbes, 1844) (see Bouchet
and Warén, 1993, fig. 1385 and Giannuzzi-Savelli et al.,
1996, fig. 408d), A. dingdensis (Janssen, 1967) (see Pon-
der, 1985, figs. 88F–G), A. geryonia (Nardo, 1847) (see
Giannuzzi-Savelli et al., 1996, fig. 395c), A. hispidula,
Monterosato, 1884 (see Gofas, 1999, fig. 26), A. punctura
(Montagu, 1803) (see Giannuzzi-Savelli et al., 1996, fig.
436), A. stephanensis Lozouet, 1998 (fig. 9D), Crisilla
semistriata (Bouchet and Warén, 1993, fig. 1535), Rissoa
parva (Da Costa, 1778) (see Ponder, 1985, figs. 79B),
and several other species. The sculptural pattern on pro-
1–3 more or less discontinuous, abapical to central, spiral
threads (also formed by short, fused, prosocline seg-
ments close to the beginning of the teleoconch) and tu-
bercles on the remaining surface, is also shown by most
of the above mentioned species and several others. Al-