Guillermo San Martín

Phylogeny of Syllidae (Polychaeta) based on morphological data

The phylogeny of Syllidae is assessed in two parsimony analyses of 107 morphological characters. The first analysis included one species of each of the 71 genera of the Syllidae, as well as members of other close families. In the second analysis, 23 poorly known genera were excluded. Character information is based on the examination of available types, additional non‐types and newly collected material. Syllidae, except Bollandia Glasby, 1994 is monophyletic. Both analyses supported three of the four traditional subfamilies (Exogoninae, Syllinae and Autolytinae) as monophyletic, whereas Eusyllinae was clearly a polyphyletic group. The genera Anoplosyllis Claparède, 1868, Astreptosyllis Kudenov & Dorsey, 1982 , Streptosyllis Webster & Benedict, 1884, Streptospinigera Kudenov, 1983 and SyllidesÖrsted, 1845 comprise a well‐supported monophyletic group, which we classified as a new subfamily: Anoplosyllinae n. subfam. Our results indicated high levels of homoplasy in the morphological characteristics that traditionally used to differentiate groups, such as the fusion of palps and the presence of nuchal epaulettes. Considering the reproductive modes, schizogamy has appeared twice in the family as the derived condition evolving from epigamy, and Exogoninae may be divided into two monophyletic groups based on the brood system.

Systematics and evolution of syllids (Annelida, Syllidae)

A large, combined phylogenetic analysis (including morphological and molecular data from 18S rDNA, 16S rDNA and cytochrome c oxidase subunit I), with the highest number of species and genera of Syllidae studied to date (213 terminals), is examined. The data were explored with different parameters and optimality criteria (parsimony, likelihood, and bayesian inference). The monophyly of Syllidae and most of the traditional subfamilies is supported. The subfamily Eusyllinae is polyphyletic, as currently delineated, but it is herein reorganized and its diagnosis modified to be a valid group. Additional well supported clades arise. The phylogenetic relationships of the well known and established genera, as well as several enigmatic genera (e.g. Anguillosyllis, Paraopisthosyllis and Parahaplosyllis), the position of which in syllid taxonomy was uncertain or dubious to date, are clarified. The results corroborate previous hypotheses about the evolution of the reproductive and brooding modes. Within Syllinae, the nature of the stolon is phylogenetically informative. The classification of the whole family is revised and discussed on the basis of this phylogenetic hypothesis.

New symbiotic associations involving Syllidae (Annelida: Polychaeta), with taxonomic and biological remarks on Pionosyllis magnifica and Syllis cf. armillaris

Several new symbiotic associations involving Syllidae (Annelida: Polychaeta) are reported. The number of known host sponge species infested by Haplosyllis spongicola is updated to 36, with seven hosts being reported for the first time (i.e. Aplysina corrugata, Aplysina sp., Cliona sp., Cliona viridis, Phorbas tenacior, one sponge from Iran, one sponge from Cambodia). Two infestation patterns (a few worms per host cm 3 in temperate waters and 10s or 100s in tropical waters) are identified. The taxonomic and ecological characteristics of the species are discussed. Five associations occurring between four syllid worms and decapod crustaccans are fully reported for the first time. Syllis cf. armillaris, S. ferrani and S. pontxioi occurred inside gastropod shells occupied by hermit crabs as well as Pionosyllis magnifica, which was also found inside the branchial chambers of the giant crab Paralithodes camtschatica. The description of Pionosyllis magnifica is emended on the basis of the new specimens found, while some taxonomic remarks on Syllis cf. armillaris are given. In addition, further evidence of sexual (P. magnifica) and asexual (S. cf. armillaris) reproduction in symbiotic syllids is provided.

Inter-population variability and character description in the sponge-associated Haplosyllis spongicola complex (Polychaeta: Syllidae)

Haplosyllis spongicola is probably the most representative symbiotic syllid harboured by sponges and has been widely reported from tropical, subtropical and temperate seas. Its external morphology seems to be very well adapted for its life-style, with all chaetae being simple and having two small teeth and a large main fang. However, the species has been the subject of a long-lasting taxonomic controversy, which gave rise to more than 15 synonymies, with hundreds of records worldwide. The present paper is based on the study of more than 28 populations obtained from around the world. These populations have been carefully analysed using different approaches (morphometry, morphology and biology). As a consequence, the existence of a pseudo-sibling species-complex within the so-called cosmopolitan H. spongicolahas been revealed. The most relevant characters (as well as their variability) that will allow a future identification of the species involved in the complex are fully described, illustrated and analysed.

“Sedentary” polychaetes of the Livingston Island shelf (South Shetlands, Antarctica), with the description of a new species

Abstract The taxonomic results of examining the “sedentary” families of polychaetes collected during the Spanish cruise “Bentart 94” off Livingston Island, South Shetland Islands, Antarctica, are presented. Most of the identified species are endemic to Antarctic and sub-Antarctic areas, but some cosmopolitan species are also present. A total of 4,022 specimens have been examined, belonging to 44 species, 42 genera and 15 families. Maldanidae and Terebellidae were the most important families in number of species, and Asychis amphiglypta, Maldane sarsi antarctica and Amphitrite kerguelensis in number of individuals. Melinna arnaudi, a new species belonging to the family Ampharetidae, is described, and Phisia rubrolineata and Aricidea (Allia) oculata are recorded for the first time since their original description.

A new genus of Syllidae (Polychaeta) from Western Australia

During a study carried out on the subfamily Exogoninae (Syllidae) from Australia, several specimens of a new genus and species were found in samples of dead coral substrate from Western Australia. They have long palps, fused except for a terminal notch, long median and two short lateral antennae, a single pair of short tentacular cirri, and short dorsal cirri, somewhat longer than the parapodial lobes. These characters resemble those of the genus Exogone Örsted, 1845. However, all these appendages are articulated. The chaetae are very similar to those of several species of Syllis Lamarck, 1818, having coarse spines on the margin of compound chaetal blades and truncated dorsal simple chaetae. Furthermore, the pharynx begins in chaetiger 3, posterior to the peristomium, as in many species of the genus Syllis; this condition does not occur in any described species of Exogone. The new genus is provisionally proposed to belong to the subfamily Syllinae, although it has some characters typical of the Exogoninae. Examination under the SEM shows another peculiar feature, the nuchal organs are distinctly laterally located. Within the Syllinae, only Paratyposyllis Hartmann-Schröder, 1962 has a single pair of tentacular cirri, but in that genus, the palps are only basally fused.

On the finding of a mass occurrence of Serpula narconensis Baird, 1885 (Polychaeta, Serpulidae) in South Georgia (Antarctica)

Abstract A new “reef ” of the serpulid polychaete Serpula narconensis Baird, 1885 is reported from the South Georgia Island shelf. This particular mass occurrence is the second serpulid “reef” reported in the Antarctic region. Its location, at 91- to 105-m depth, is very different from those serpulid reefs previously reported, usually sited at intertidal zone or at low depth, and this may be one of the largest, if not the largest, serpulid reef in the world.

Syllidae (Annelida: Polychaeta: Phyllodocida) from the Chausey Archipelago (English Channel, France), with a description of two new species of the Exogoninae Prosphaerosyllis

Specimens of Syllidae (Polychaeta) were collected from a coarse sediment habitat in the intertidal zone of the Chausey Archipelago (English Channel, France). Twenty-one species of Syllidae were identified in this zone, including two new species, which are described herein. Prosphaerosyllis chauseyensis, n. sp. is characterized by a distinct digitiform papilla on antennae, tentacular and dorsal cirri, and by the presence of two sizes of dermal papillae without any specific arrangement. Prosphaerosyllis laubieri, n. sp. is a minute sized species with dorsal cirri similar throughout the body and with small, scattered papillae on the dorsum and ventrum, which are longer and numerous on the palps. One species was reported for the first time in the north-east Atlantic (Parapionosyllis brevicirra) and six were new for both France and the English Channel (Prosphaerosyllis giandoi, Sphaerosyllis glandulata, Sphaerosyllis taylori, Streptosyllis campoyi, Syllis licheri, and Syllis pontxioi).

Re-description of some enigmatic genera of Syllidae (Phyllodocida: Polychaeta)

Several type series of unusual and poorly known genera of Syllidae have been examined. New diagnoses for the following genera and re-descriptions of their type species are provided: Anguillosyllis , Clavisyllis , Lamellisyllis and Nuchalosyllis ; Brachysyllis , previously synonymized with Dioplosyllis , is herein considered to be a valid taxon. The species Brachysyllis infuscata is also re-described. Three genera are considered to be non-valid taxa: Braniella , synonymous with Anguillosyllis ; Alluaudella , synonymous with Odontosyllis ; and Exogonella , synonymous with Parexogone . Their type species herein are re-described and assigned to their corresponding valid genus. Finally, Exogonoides is considered nomina dubia since its relationships with other syllids could not be established. Keys to species of Anguillosyllis and Brachysyllis are also included.

Description and life-history traits of a new species of Proceraea with larvae infecting Abietinaria turgida (Polychaeta, Syllidae & hydrozoa, sertulariidae)

Abstract A new species of the genus Proceraea (Polychaeta, Syllidae, Autolytinae), P. rzhavskyi, is described. Many specimens of this species at different stages of development were found within the hydrothecae and mucous tubes attached to colonies of the sertulariian hydrozoan Abietinaria turgida (Clark, 1867) at the coast of Mednyy Island, the Commander Islands, Northwest Pacific, 5–12 m depth, in August Larvae and juveniles are present within the hydrothecae from very early stages of development, which appears to be direct. This is the first report of a polychaete with symbiotic larval stages and free-living adults. The smallest specimens have a yolk, a single pair of eyes, and a tuft of short cilia at the apical part of prostomium, but lack setae. As larvae grow, the yolk and the tuft of cilia disappear. Setae and dorsal cirri appear on several anterior segments, the pharynx develops, and juveniles start feeding upon the host. Finally, they occupy the entire cavity of the hydrothecae. A conspicuous tubular addition to the hydrotheca is formed distally as a result of infestation. Upon reaching 10–11 setigers, the juveniles leave the hydrotheca, build mucous tubes attached to the stem or branches of the colony and continue their growth up to the adult stage. The proventriculus and the teeth of the trepan are formed when the worms leave the hydrothecae. Unlike Autolytus all the stages lack ciliary bands on the body. A female stolon (sacconereis) was examined. Proceraea rzhavskyi differs from closely related species, P. okadai and P. mukaishimus, in structure of the trepan and length of head appendages and nuchal epaulettes.