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Monterosato: Acinus cingulatus, 2, Messina, 1014); SE
Sicily, Siracusa, Peninsula of Magnisi, south side, detritus
from the beach, 1 sh., coll Garilli, 6/2006
Habitat: Unknown. It is noteworthy that sandy and
Posidonia bottoms prevail in the south side of the Mag-
nisi Peninsula (from where I collected the beached shell
in Figure 24), while an almost paralic (pre-lagoon) envi-
ronment (with Cerastoderma, Cerithium, and Gibbula
spp., on a finely sandy bottom) and a rocky bottom with
algae characterize the north and east sides.
Distribution: Its distribution appears to be limited to
Sicily, with particular regard to the eastern coast, from
Messina to Magnisi. It was recorded from Palermo by
Monterosato (1872; 1875; 1878; 1884a; 1884b), who very
likely followed the citations of Philippi (1844) and
Weinkauff (1885). The latter author, who indicated Mon-
dello (the beach near Palermo), also cited Ognina (Cata-
nia) in eastern Sicily. To my knowledge, no fossil record
of this species exists.
Remarks: This is a very rare, practically unknown spe-
cies (see Van Aartsen, 1982a). Its identification has tra-
ditionally been quite problematic, above all after the
misidentification by Piani (1979, figs.2–3), who illus-
trated a juvenile shell of Alvania carinata (Da Costa,
1778) under the name Galeodina cingulata (Philippi,
1836). The shell figured by Giannuzzi-Savelli et al. (1996,
fig. 499), under the name Alvania (Alvania) cingulata
(Philippi, 1836), is a subadult of A. carinata.
My identification is based on three shells (one from
the type locality, two from ZMB ex Monterosato coll.,
labelled as Acinus cingulatus), which agree well with the
original description by Philippi (1836; see also 1844:
128). A few diagnostic characters allow for its correct
identification: the primary cingulated sculpture with
raised cords, numbering 10–11 on the last whorl; the
secondary axial pattern formed by very narrow ribs cross-
ing the cords; the large ovate aperture; and the internally
smooth outer lip, slightly thickened near its edge.
As Philippi (1844) noted, Alvania cingulata may be
compared with A. tenera, especially with the slender
morph of the latter species (see Figure 78). Alvania te-
nera has a smaller shell (usually not over 2.2 mm in
height) with more raised cords (numbering 12–14 on the
last whorl), and almost lamella-like ribs, which occur just
on the interspaces between the cords (see discussion of
A. tenera). Furthermore, A. cingulata has a paucispiral
protoconch.
In addition, Nordsieck (1972) and Van Aartsen (1982)
considered this species as belonging to Galeodina. How-
ever, the similarity between Alvania cingulata and A.
carinata (type species of Galeodina) is superficial. Sev-
eral differences separate the two: A. cingulata has a less
inflated last whorl bearing less numerous cords and lack-
ing varices, its outer lip lacks a varicose thickness, and its in width (2.8 mm in holotype). Protoconch conical, mul-
spiral sculpture does not markedly dominate over axial as
in the typical A. carinata. The latter species also has a
multispiral protoconch.
THE NAUTILUS, Vol. 122, No. 1
Monterosato (1884a and 1884b) included this species
in his genus Acinus (synonym of Alvania according to
Ponder, 1985), creating a link with the type species Al-
vania cimex (Linnaeus, 1758) (which is also the type
species of Alvania, see Ponder, 1985: 36), mainly based
on coloration. In reality, the similarity between the two
species is limited to the color pattern of the shell and the
nodular sculpture. Strong differences indicate that A.
cingulata and A. cimex could be distant relatives, the
latter having a more sturdy shell with a coarser sculpture
(with subequal axial and spiral), and a proportionally
smaller aperture provided with an internally denticulate
outer lip. The concept of A. cingulata as expressed by
Monterosato (1884b: p. 62) seems to be applicable to an
interesting Alvania sp. (from the lower Pleistocene of
southern Italy, Reggio Calabria, Musalà, 19 shs, F95A,
coll., Figures 27–29) rather than to the original descrip-
tion by Philippi. The non-planktotrophic (see the pau-
cispiral protoconch in Figure 29) Alvania sp., illustrated
here, showing only a moderate similarity with the teleo-
conch sculpture of A. cingulata, has the characteristic
general shape of A. cimex, with which it shares the ap-
ertural features, including the denticulations on the inner
part of the outer lip. Furthermore Monterosato himself
determined the shells I have illustrated in Figures 15–23
as A. cingulata.
In 1968, Nordsieck cited A. cingulata as Cingula
(Onoba) cingulata. In reality, a vague similarity with
some Cingula Fleming, 1828 or (more specifically)
Onoba H. and A. Adams, 1852, species exists; e.g. Onoba
(O.) carpenteri (Weinkauff) (see Ponder, 1985: fig.
114a), bears a similar spiral sculpture. Anyway, the genus
Onoba is characterized by usually elongate shell with a
proportionally smaller and more rounded aperture. Its
included species, usually lacking the axial sculpture, may
have a much weaker axial pattern or this may consist of
delicate ribs, which become obsolete towards the sutures
(see Bouchet and Warén, 1993: figs. 1508–1509, 1514–
1515). In addition, the protoconch sculpture apparent on
some non-planktotrophic Onoba species resembles that
of A. cingulata, in having few, very fine spiral widely
spaced threads. This kind of sculpture is also seen in
Alvania (e.g. A. subsoluta (Aradas, 1847), see Bouchet
and Warén, 1993, fig. 1458). Cingula species appear to
be less similar to A. cingulata in having a thick outer lip
and lacking any axial sculptural pattern.
A certain similarity exists with Alvania watsoni (Wat-
son, 1873) from Madeira (see Ponder, 1985: fig. 102c–d),
with which A. cingulata shares the general shell shape,
characterized by an inflated last whorl provided with a
large, ovate aperture.
Alvania francescoi new species
(Figures 30–43)
Description: Shell small, sturdy, conical-ovate, reach-
ing 4.8 mm in height (4.3 mm in holotype) and 3.1 mm
tispiral with partially immersed nucleus and convex