Zootaxa, Taxonomy of Serpulidae (Annelida ... - Magnolia Press

Introduction
The family Serpulidae is a discrete group of sedentary calcareous tubeworms within the large clade Sabellida,
which shares a presence of radiolar crown and separation of the body into thoracic and abdominal regions, as
divergence from the usually rather uniformly segmented motile polychaete form. The views on the
relationships within Serpulidae have undergone many changes over the years (see Kupriyanova et al. 2006 for
the details). The Serpulidae Rafinesque, 1815 had been traditionally divided into subfamilies Serpulinae
Rafinesque, 1815 (although probably in most papers attributed to MacLeay, 1840) and Spirorbinae
Chamberlin, 1919 until Rioja (1923) established the subfamily Filograninae. Pillai (1960) included 5
brackish-water serpulid genera in the subfamily Ficopomatinae but ten Hove & Weerdenburg (1978) revised
the group and placed all its genera in the genus Ficopomatus. Uchida (1978) created 11 sub-families and
numerous new genera, but his scheme, strongly criticized by ten Hove (1984) has not been accepted widely.
Pillai (1970) elevated Spirorbinae to the family Spirorbidae, but later a number of authors suggested that
Spirorbidae are more closely related to Serpulinae than to Filograninae (ten Hove 1984, Fitzhugh 1989, Smith
1991, Rouse & Fitzhugh 1994) and that the maintenance of the family Spirorbidae is not justified. Recent
phylogenetic analyses confirmed the position of Spirorbinae as a subfamily of Serpulidae (Kupriyanova 2003,
Kupriyanova et al. 2006, Lehrke et al. 2007, Kupriyanova & Rouse 2008). Ten Hove (1984) regarded the
Filograninae as paraphyletic and a morphology-based cladistic analysis of some Serpulidae (Kupriyanova
2003) supported his conclusions. Moreover, the most recent phylogenetic analyses of Serpulidae using 18S
ribosomal DNA (Lehrke et al. 2007) and another using combined molecular and morphological data
(Kupriyanova et al. 2006) suggested that both traditionally formulated sub-families Serpulinae and
Filograninae are not monophyletic. Kupriyanova et al. (2006) refrained from revising the serpulid
classification and suggested that a major revision of serpulid taxonomy is needed based on more genera than
used in their study.
The major obstacle to a comprehensive phylogenetic analysis of the Serpulidae remains the state of its
alpha taxonomy. It is almost proverbial to say that serpulid taxonomy is very confused and most currently
recognized serpulid genera have long and convoluted taxonomic histories. Within Serpulidae, specific
identification has traditionally been based on a combination of characters such as morphology of the
operculum and opercular peduncle (if present), degree of development of the collar and thoracic membranes,
structure of collar chaetae and tube and, to a lesser degree, structure of chaetae and uncini. Serpulid genera
have been described on the basis of unique characters or on unique combinations of characters (even on
absence of characters) rather than on presence of shared derived characters. Although traditionally only few
characters have been used in serpulid taxonomy, variability of these characters remains largely unstudied.
There have been very few reviews of serpulid taxonomy. The very first revision (Mörch 1863) was
followed by early reviews by Saint-Joseph (1894), Bush (1905), and Pixell (1912, 1913). Chamberlin (1919)
gave a key to the serpulid genera without attempting to revise the family, and so did Southward (1963), half a
century later. Fauchald (1977) compiled a list of generic diagnoses and a key to genera for all polychaetes,
including serpulids and spirorbids. In addition to the Spirorbidae, he acknowledged 331 species of serpulids,
divided into 3 sub-families; the Serpulinae with 44 genera, the Filograninae with 5 genera, and the
Ficopomatinae with 5 genera. Of these 54 genera, 22 were monotypic and another 13 had only 2 species.
Uchida (1978) provided a systematic review of the group with a description of new species and new genera,
but gave no key. He mentioned only 233 species, as compared to the 331 of Fauchald (1977). Of the 61 genera
distinguished by Uchida (1978), 26 were monotypic, and 15 had only two species. No attempts to review
Serpulidae have been made ever since and now, thirty years later, Fauchald (1977) still remains the most
commonly used source of information on the generic composition of serpulids. During the last three decades
serpulid taxonomy underwent significant changes, with numerous taxa being synonymized, older diagnoses
emended and extended, new species described and about 10 genera added.
TAXONOMY OF SERPULIDS: STATE OF AFFAIRS
Zootaxa 2036 © 2009 Magnolia Press · 5