Vol. 92 (1)
January 31, 1978
The Nautilus 41
A NEW GENUS OF OPERCULATE LAND SNAILS
FROM HISPANIOLA WITH COMMENTS ON
THE STATUS OF FAMILY ANNULARIIDAE
Fred G. Thompson
Florida State Museum
University of Florida
Gainsville, Florida 32611
Hispaniola is inhabited by many exquisite land
animals. It has an especially rich and diverse
gastropod fauna. Although much has been written
about Hispaniolan mollusks, large geographic areas
remain virtually unexplored for land snails and
many new forms remain to be described. During
the past two years I spent about eight months in
the field in the Dominican Republic and made ex-
tensive collections of land snails from most areas of
the country.
The physiography of Hispaniola is complex. It
consists of many mountain ranges, ridges, and
isolated hills, all of which combine to form a mosaic
of faunal regions. The Cordillera Central consists
mostly of igneous and metamorphic rocks, and
calciphyllic families of land snails, such as the
Urocoptidae and Annulariidae, are conspicuously
absent. Elsewhere, to the north, east, and south,
calcareous substrates predominate. In these areas
some hills and mountain ranges have a high degree
of molluscan endemism. One such mountain ridge
in Puerto Plata Province is inhabited by a most
unusual land snail, whose transparent shell with
high fragile ribs cause it to resemble a giant
snowflake. It is one of the most striking terrestrial
operculates to have been discovered. The trans-
parent, high ribs of the shell is an adaptation for a
cryptic existence on an exposed limestone surface.
The snail is highly unnoticeable because of the
blurred image that is created by its sculpture. This
delicate, ornate sculpture is unrivaled by any other
known species of "cyclostomid," although similar
ornamentation occurs in some members of the
pupinid genus Geothauma from Borneo.
The snail described herein is a member of the
family Annulariidae and the subfamily An-
nulariinae as defined by Henderson and Bartsch
(1920) Controversy exists over the availability of
the generic name Annularia Schumacher, 1817 as
opposed to Choanopoma Pfeiffer, 1848 and An-
nulariidae as opposed to Chondropomidae or
Pomatiasidae (see Henderson and Bartsch, 1920;
Baker, 1924a: 2-3, Solem, 1960: 419-420; 1961: 192-
194). This case is currently before the international
Commission on Zoological Nomenclature. For pur-
poses of this paper I tentatively accept Dall's (1905:
298) type species designation of Turbo lineina Lin-
naeus for Annularia. Annulariidae Henderson and
Bartsch (1920: 54) has page priority over Chon-
dropomi-(dae) Henderson and Bartsch (1920: 59). I
arbitrarily follow the subfamily division proposed
by Henderson and Bartsch (1920) and Baker
(1924a). Later authors, who criticized Henderson
and Bartsch 's classification, did not provide more
useful alternatives. For reasons given below I con-
sider the neotropical Annulariidae and the Old
World Pomatiasidae to be separate families.
Licinae Pfeiffer, 1858 was the first family-group
taxon name used for the neotropical "cyclostomes."
Except for occasional use in the mid-nineteenth
century the name went unmentioned in the
primary literature until Golikov and Starabogatov
(1975) resurrected it as the family name Licinidae.
The name Licinidae Pfeiffer is a nomen oblitum
because of this great time lapse and thus is not
available for use (ICZN Article 23, b).
Field work relating to this study was supported
by the National Geographic Society, Council for
Research, and the Florida State Museum. I am
grateful to officials of both organizations for the
support they have given me. Dr. Joseph Rosewater
(USNM) and Dr. Charlotte Patterson (UMMZ) kind-
ly loaned to me dried specimens of Cistulops and
Ti-osc.hehnndex from which radulae were extracted
BioStor
