MALACOLOGIA, 2004, 46(1): 79-125
PRELIMINARY PHYLOGENETIC STUDY OF BRADYBAENIDAE (GASTROPODA:
STYLOMMATOPHORA: HELICOIDEA)
Min Wu
Hebei University, IHezuolu 1, Baoding 071002, Ciiina;
[email protected]
ABSTRACT
Morphological variation in the terminal genitalia of genera of Bradybaeninae is compared
and discussed. This is the first attempt to study the anatomy of the endemic Chinese
bradybaenids Catiiaica {Pliocattiaica), Pseudiberus (Platypetasus), and l\/letodontia.Apre-
liminary phylogenetic analysis of bradybaenids was performed based on the character
matrix from the present study. The focus was primarily on the terminal genitalia. He/zx
(Helicidae) and Camaena (Camaenidae) were used as outgroups. The results suggest that
several previous taxonomic arrangements for the subdivision of this family, based on the
analyses using shell features and/or superficial anatomy of genital system, are unsuitable.
The cladistic analysis suggests that the use of the subfamily Helicostylinae, sensu lato,
might not be suitable for use as the sister group of the known Bradybaeninae.
Two new endemic genera from western China are described based on the comparison
of the terminal genitalia: Aegistohadra n. gen. and Eueuhadra n. gen. They are monophyl-
etic and are readily distinguished from other bradybaenids by a synapomorphy, the pres-
ence of penial caecum. Nanina delavayana Heude, 1885, is designated as the type species
of Aegistohadra. The type species of Eueuhadra is a new species, E. gonggashanensis.
Key words: Stylommatophora, Helicoidea, Bradybaenidae, China, terminal genitalia,
phylogeny, phylogenetic analysis, new taxa.
INTRODUCTION
The Bradybaenidae (= Bradybaenidae +
Helicostylidae, sensu Schileyko 1991) are a
large group of terrestrial snails widely distrib-
uted in eastern Asia, with one species in Eu-
rope. Historically, more than 150 authors
(Richardson, 1983; Wu, unpublished cata-
logue) have published on Chinese
bradybaenids. However, most work on the
classification of higher taxa of China was
based on shell, not anatomical characters
(Pilsbry, 1888-1894; Möllendorff, 1899;
Dautzenberg, 1914-1915; Bavay &
Dautzenberg, 1900, 1915; Blume, 1925; Ping
& Yen, 1932; Yen, 1939; Zilch, 1940; almost
all previous work). Therefore, knowledge on
the bradybaenid systematics has remained
unsatisfactory.
The monograph by Wiegmann (1900), in
which species from 12 genera and subgenera
are described, was the first study dealing spe-
cifically with the anatomy of bradybaenid geni-
talia. More recently, some malacologists have
made comparative studies of the genital mor-
phology, mainly based on their native
bradybaenid taxa (Schileyko, 1978; Azuma,
1982; literature of Japanese workers, cited by
Nordsieck, 2002; Lee & Kwon, 1993, 1994;
Wu, 2001; Wu & Quo, 2003). Many authors
have focused on the general structures, such
as the size of dart sac, the presence/absence
of a flagellum, and the number of mucous
glands. Schileyko (1978) gave a much more
precise, detailed description of the terminal
genitalia of Russian bradybaenids that in-
cludes the above traditionally described char-
acter and internal dissections of the penis and
dart apparatus. More recently, Nordsieck
(1 987) stated that the bradybaenid groups are
characterized by apomorphies of the genital
organs.
However, similar work covering most en-
demic Chinese bradybaenid taxa, which is
essential for understanding the general
anatomy of bradybaenids and construction of
a sound taxonomic framework, has been lack-
ing.
The present work compares the structure of
the terminal genitalia of some genera of the
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Specimen codes extracted from OCR text.
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