Contributions to the taxonomy of Sabellidae (Polychaeta)

The genus Potamilla Malmgren is particularly characterized by dorsal lips which lack any radiolar midrib; Pseudopotamilla Bush by compound radiolar eyes, dorsal collar lappets and flanges alongside the bases of the most dorsal radioles; Demonax Kinberg by a wide dorsal collar gap and companion setae with big heads and narrow blades; and Potamethus Chamberlin by an elongated first segment, enlarged ventral sacs, very long shafts to the thoracic uncini, and inferior abdominal setae much shorter than the superior ones. Perkinsiana gen. nov . lacks most of these characters, but the type species 'Potamilla' rubra Langerhans is remarkable in having red blood. It bores into limestone abundantly off S Wales and is here redescribed. Oriopsis hynensis sp. nov . from SW Ireland has a smooth collar set low on the first segment, with its ventral margin entire and free from the apex of the peristome. The new name Demonax langerhansi is proposed for Sabella (Potamilla) incerta Langerhans non Demonax incertus Kinberg.     

New fan worm genera and species (Polychaeta, Sabellidae, Fabriciinae) from the western Pacific, and cladistic relationships among genera

Five new species are described from among the genera Fabriciola Friedrich, 1939 (one species from Okinawa), Novafabricia Fitzhugh, 1990 (two species from Australia and Papua New Guinea, respectively), and two new monotypic genera, Brifacia gen. n. (Australia), and Pseudoaugeneriella gen. n. (Okinawa). All species are known only from the intertidal. Fabriciola rubra sp. n. is a member of the species complex with red peristomial and pygidial eyes, inferior thoracic flagellate setae, and abdominal pin-head setae. Novafabricia labrus sp. n., and N. exiguus sp. n., are distinguished from other species based on the distribution of inferior thoracic pseudospatulate setae. Brifacia metastellaris sp. n., resembles Fabricia stellaris (Müller, 1774) with regard to anterior peristomial ring collar construction and distribution of pseudospatulate setae, but differs in having abdominal uncini with relatively short manubria. Pseudoaugeneriella unirama sp. n., most closely resembles species of Augeneriella Banse, 1956 in general form, but has unbranched vascularized ventral filamentous appendages. Revised keys to fabriciin genera and selected species are provided. Cladistic relationships of these new genera and species to other Fabriciinae are examined and the status of some characters are reviewed. Whereas previous analyses have supported a monophyletic Augeneriella on the basis of branched, vascularized ventral filamentous appendages, present results show Augeneriella paraphyletic relative to Fabricia Blainville, 1828, Novafabricia, Fabricinuda Fitzhugh, 1990 Parafabricia Fitzhugh, 1992 and Brifacia. Similarly, some topologies show Novafabricia, which has only been defined by the presence of poorly developed dorsal lips, to be paraphyletic relative to Fabricia, Fabricinuda, Parafabricia, and Brifacia. The cladistic analyses do, however, support recognition of Brifacia and Pseudoaugeneriella. With the addition of Brifacia, the presence of unbranched, vascularized appendages is plesiomorphic for the Fabriciinae, which has not been previously hypothesized.     

The genera <Emphasis Type="Italic">Bispira</Emphasis> Krøyer, 1856 and <Emphasis Type="Italic">Stylomma</Emphasis> Knight-Jones, 1997 (Polychaeta,Sabellidae): systematic revision,relationships with close related taxa and new species from Australia

A cladistic analysis undertaken to test monophyly of Bispira and Stylomma (including new species of both genera) and to ascertain relationships with related taxa reveals that Bispira is paraphyletic without the inclusion of Pseudobranchiomma and Branchiomma, and that Stylomma is monophyletic due to the presence of a structure on the dorsal basal flanges which has never been described before. New species of Bispira and Stylomma from Australia are described. Bispira serrata n. sp., differs from the other species of the genus in having serrated radiolar flanges whereas all other Bispira species have smooth flanges or lack them, and also by the shape of the thoracic and abdominal uncini, which are short-handled and have 2–3 rows of big teeth above the main fang, instead of having medium-sized handles and small, numerous rows of teeth over the main fang. Stylomma juani n. sp., is characterized by the presence of serrated radiolar flanges and unpaired compound eyes along the branchial radioles, whereas other species in the genus have smooth radiolar flanges and subterminal compound radiolar eyes. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Handling editor: K. Martens     

A revision of Sabella, Bispira and Stylomma (Polychaeta: Sabellidae)

Sabella is rediagnosed to include only species that have spiralled fascicles of abdominal chaetae, first thoracic shield with straight anterior border and radioles that lack composite eyes and flanges. Spirographis spallanzanii is synonymous with Sabella penicillus . The type of the genus is discussed and a neotype designated. The only other species retained in Sabella are S. pavonina and S. discifera ( = Branchiomma linaresi , once misplaced in Megalomma , but abdominal fascicles of Megalomma form transverse rows). Most species formerly placed in Sabella are transferred to Bispira , having C-shaped fascicles of abdominal chaetae, first thoracic shield with a 'W-shaped anterior border and, in most species, radioles with paired composite eyes and flanges. Bispira , with B. volutacornis as the type species, is rediagnosed to include B. crassicomis, B. fabricii, B. melanostigma, B. tricyclia, B. viola, B. manicata, B. poricfera, B, mariae, B. elegans, B. brunnea, B. guinensis, B. secusolutus, B. wireni, B. oatesiana, B. spirobranchia, B. pacifica, B. monroi , and B. turneri , many of which are described fully for the first time. Only five of these form bispiral crowns (bispirality is useful only specifically and occurs in other genera) and one, B. tricyclia , has a unispiral crown. Sabella palmata Quatrefages, the type of Stylomma is redescribed and its synonyms discussed. This genus has abdominal fascicles like those of Bispira , but radiolar eyes like those of Megalomma . The relative advantages of chaetal arrangement and eye position are discussed.     

Snowflakes and feather-dusters – some challenges for soft-bottom fanworm systematics

The present study highlights paraphyly within traditional soft-bottom sabellin fanworm taxa. Two forms of the sabellid radiolar crown are recognised. The `snowflake' crown style comprises three pairs of radioles only, with few pinnules alternating along the length of the radioles and longest mid-radiole. The `feather-duster' crown style comprises few to many pairs of radioles, with numerous paired pinnules of relatively even length. Cladistic analyses revealed two new groups, whose respective members were assigned previously to Euchone and Jasmineira. These are pending revision and naming. Phylogenetic nomenclature is proposed as a more informative alternative to traditional Linnean nomenclature.     

Ontogenetic variations in characters of Euchone analis (Krøyer, 1856) (Polychaeta, Sabellidae, Sabellinae) from Spitsbergen, and new assignments of Oriopsis ingelorae Plate, 1995 and O. liefdefjordensis Plate, 1995

Euchone analis, the type species of its genus, was collected in high densities and in different size classes from Kongsfjorden, west Spitsbergen. This material has provided the basis for an investigation of the size dependence of characters. Almost all characters used in diagnoses were highly variable, especially the number of abdominal chaetigers forming the anal depression and the shape of the depression. The only relatively constant features are the number of chaetigers anterior to the anal depression and the branchial crown‐to‐body length ratio. A branchial skeleton extension of the radiolar appendages of the dorsal lips was found for the first time within Euchone, and this character has been added to the diagnosis of Euchone. Oriopsis liefdefjordensis and small specimens of E. analis agree in all characters, and O. liefdefjordensis is proposed to be a junior synonym of E. analis. Characters found in O. ingelorae are in accordance with those described for Chone, and we propose assigning O. ingelorae to this genus. The significance of ontogenetic character variations in the Sabellidae is discussed.     

A new species of Heterosentis Van Cleave, 1931 (Acanthocephala, Arhythmacanthidae), a parasite of pinguipedid fishes in the southwest Atlantic

A new species of arhythmacanthid acanthocephalan, Heterosentis martini n. sp., parasitic in the Argentinean sandperch Pseudopercis semifasciata (Cuvier) (Perciformes, Pinguipedidae) from the coasts of Argentina is described. Heterosentis martini n. sp. differs from all congeneric species by having 10 longitudinal rows of hooks in the proboscis, each with 7-8 hooks, consisting of 1 medium apical and 3 larger sub-apical hooks with root, and 3-4 smaller, basal, curved hooks with rudimentary roots and spines in both ventral and dorsal regions of the body. The most similar species, Heterosentis heteracanthus (Linstow, 1896) Van Cleave, 1931, and Heterosentis brasiliensis Vieira, Felizardo and Luque, 2009, also have 10 longitudinal rows of hooks, but H. heteracanthus differs from the new species by having only 3-5 (more frequently 4) hooks in each row, with only the anterior hook large and bearing a developed root. Heterosentis brasiliensis differs from the new species by possessing 2 sub-apical hooks in each row (instead of 3), similar body length but shorter proboscis, and trunk spines restricted to the ventral surface of body.     

Orbiniidae polychaetes (Polychaeta: Scolecida) from Coiba Island, eastern Pacific of Panama, with description of a new species

Santa Cruz and El Gambute, two mangrove systems with associated tidal flats, were sampled in Coiba National Park, Coiba Island, Pacific of Panama. At each site, two samplings were done at low, middle and high intertidal levels in February and November of 1997. A new orbiniid species were found: Orbinia oligopapillata n. sp. is characterized by having 15-16 thoracic chaetigers with four or five rows of uncini and up to three papilliform postchaetal processes on neuropodial lobes by the abdominal parapodia bearing flail-tipped neurochaetae, and by the presence on anterior-most abdominal chaetigers of interramal cirri and a low number of subpodial and stomach papillae. A specimen belonging to genus Leitoscoloplos Day, 1977 is described as "Leitoscoloplos sp.", characterized by the lateral pouches on its abdominal chaetigers, a unique case for the family because these brooding structures have only been previously cited in two species of Scoloplos. Naineris sp. is characterized by the number of its thoracic chaetigers, branchiae, uncini and bilobed abdominal neuropodia with protruding aciculae.     

Two new species of an atypical group of Pseudobranchiomma Jones (Polychaeta: Sabellidae)

The genus Pseudobranchiomma Jones, 1962 can be divided into three groups: (A) those with paired serrated flanges along all or most of the crown radioles, as in the type species P. emersoni Jones, 1962; (B) those with such flanges only on the distal parts of the radioles; (C) those with flanges reduced or absent (without serrations) as in two new species described here from Florida and Italy. Group C also contains Pseudobranchiomma longa (Kinberg, 1867), P. punctata (Treadwell, 1906) and P. minima (Nogueira & Knight-Jones, 2002). Lists of species (and their synonyms) in the other two groups are given, and scissiparity, thoracic length, chaetal arrangements and types of radiolar eyes are discussed.     

New Fabriciola species (Polychaeta, Sabellidae, Fabriciinae) from the eastern Atlantic, with a description of sperm and spermathecal ultrastructure

New species in the genus Fabriciola Friedrich are described. Fabriciola is defined by a single synapomorphy, the presence of non-vascularized, ventral filamentous appendages. Otherwise the genus is variable, with differences among species in chaetae, eyes, and peristomial organization. The new species, Fabriciola flammula, F. liguronis and F. parvus , reflect this heterogeneity. Fabriciola liguronis has spermathecae in the radiolar crown of females, the first record of these structures in Fabriciola , but F. flammula and F. parvus lack spermathecae. Sperm ultrastructure in all three species share apomorphies with other fabriciins, but vary in other respects. Fabriciola may be paraphyletic, but material of the type species F. spongicola (Southern, 1921) has been unobtainable so far, and detailed study of this species is required to define the genus Fabriciola adequately.     

Morphology,Morphogenesis and Small Subunit rRNA Gene Sequence of a Soil Hypotrichous Ciliate,Perisincirra paucicirrata (Ciliophora,Kahliellidae), from the Shoreline of the Yellow River,North China

The morphology, morphogenesis, and 18S rRNA gene sequence of a soil hypotrichous ciliate Perisincirra paucicirrata, isolated from north China, were investigated. Perisincirra paucicirrata differs from its congeners in: (1) having a body length to width ratio in vivo of 4:1, (2) its adoral zone occupying between 15% and 25% of the total body length, and (3) the presence of two parabuccal cirri, three left (with 10–16 cirri each) and two right marginal rows (with 14–24 cirri each), and three dorsal kineties. Our study offers a first attempt to begin to map the morphogenetic processes of the genus, which are mainly characterised by the following: the formation of four frontal ventral transverse anlagens for each daughter cell, with the proter's anlage I originating from the reorganised anterior part of the parental paroral; the paroral and endoral anlage developed from the reorganised old endoral and do not contribute the first frontal cirrus; the frontoventral transverse anlage I contributing the left frontal cirrus; anlage II generating the middle frontal and the buccal cirri; anlage III developing the right frontal cirrus and the anterior parabuccal cirrus; and anlage IV contributing the posterior parabuccal cirrus. As an additional contribution, we judge that the inner one or the two right rows of P. kahli and P. longicirrata are marginal rows. Phylogenetic analysis based on SSU rDNA sequences suggests that Perisincirra is related to sporadotrichids, but provides no credible evidence for its taxonomic position.     

Neotropical Monogenoidea. 33. Three new species of Ancistrohaptor n. g. (Dactylogyridae,Ancyrocephalinae) on Triportheus spp. (Teleostei,Characidae) from Brazil,with checklists of ancyrocephalines recorded from neotropical characiform fishes

Three new species of Ancistrohaptor n. g. are described from the gills of three species of Triportheus (Characidae) collected from the environs of Manaus, Amazonas, Brazil: A. falcatum n. sp. from T. elongatus; and A. falciferum n. sp. and A. falcunculum n. sp. from T. angulatus, T. albus and T. elongatus. Ancistrohaptor n. g. is proposed for species possessing overlapping gonads, a dextral or dextroventral vaginal aperture, a coiled (counter-clockwise) male copulatory organ, two accessory pieces in the copulatory complex, and a haptor armed with two pairs of anchors (ventral anchor with elongate shaft), dorsal and ventral bars and 14 hooks; hook pair 1 (ventral) anterior to ventral bar, pairs 2–4 (ventral) lying bilaterally anterior to ventral anchor bases, pair 5 (ventral) associated with distal end of ventral anchor shafts, and pairs 6 and 7 (dorsal) bilateral about midway along haptoral length. Parasite-host and host-parasite lists of the Ancyrocephalinae from neotropical Characiformes are provided.     

Morphology and infraciliature of three species of Metaurostylopsis (Ciliophora, Stichotrichia): M. songi n. sp., M. salina n. sp., and M. marina (Kahl 1932) from sediments, saline ponds, and coastal waters

Two new urostylid ciliates, Metaurostylopsis songi n. sp. and Metaurostylopsis salina n. sp. and Metaurostylopsis marina (Kahl 1932) are investigated using live observation and protargol impregnation. These species were isolated in Korea from intertidal sediments, saline ponds, and coastal waters. Metaurostylopsis songi is in vivo about 120 microm x 25 microm, has a slenderly ellipsoidal body, colorless cortical granules in rows on ventral and dorsal body sides, about 54 macronuclear nodules, 28-47 adoral membranelles, five frontal, two or three frontoterminal and six or seven transverse cirri, and 9-12 midventral cirral pairs followed posteriorly by 1-3 single cirri. In vivo M. salina is about 60 microm x 25 microm, has a pyriform body, colorless cortical granules irregularly arranged, about 45 macronuclear nodules, 18-23 adoral membranelles, three frontal, three to five frontoterminal and two to five transverse cirri, and four or five midventral cirral pairs followed posteriorly by five to seven single cirri. Both species have three marginal cirral rows on each body side and 3 long dorsal kineties. The Korean specimens of M. marina match the Chinese population in all main features. Metaurostylopsis songi differs from M. marina by the more slender body, the number of frontal cirri (invariably five vs. four), and the arrangement of cortical granules (in rows on dorsal and ventral cortex vs. only along dorsal kineties and anterior body margin). Metaurostylopsis salina differs from its congeners by the distinctly smaller size, the pyriform body shape, the scattered cortical granules (vs. in rows), and number of frontal cirri. It differs from M. marina also by the number of midventral cirral pairs (four or five vs. seven to 11).     

Morphology and small subunit rDNA phylogeny of a new soil ciliate, Bistichella variabilis n. sp. (Ciliophora, Stichotrichia)

We isolated a new ciliate, Bistichella variabilis n. sp., from slightly saline soil of the Yellow River Delta in China and studied it using live observation, protargol staining, and small subunit (SSU) rRNA gene sequencing. Bistichella variabilis is elongated ellipsoidal and about 220 × 70 μm in vivo, with a variable number and arrangement of cirri- ventral row VI mostly very short, but a long row observed also in one specimen, and an extra row occasionally exists besides the left or the right marginal row. Bistichella variabilis differs from all congeners except Bistichella buitkampi (Foissner, 1982) in the macronuclear pattern (four vs. two or many nodules); and from B. buitkampi by the usual oblique arrangement of transverse cirri (vs. perpendicular); and the ventral row VI mostly restricted in the posterior quarter of the cell (vs. long and stretching to the anterior quarter). Phylogenetic analyses of SSU rDNA sequences indicated that B. variabilis grouped with the clade of Orthoamphisiella breviseries and Uroleptoides magnigranulosus with high support values. Despite their distinct differences in morphology, these three species have sequence similarities of 99.5-99.7%. Nonetheless, it is still premature to assign Bistichella together with Uroleptoides to the family Orthoamphisiellidae because of the taxonomic uncertainties and undersampling.     

Martinssonia elongata gen. et sp.n., a crustacean-like euarthropod from the Upper Cambrian 'Orsten' of Sweden

A tiny arthropod, with five growth stages, is described. Three of the instars are metanauplius-like larvae, having unsegmented bodies and four pairs of appendages. The largest stage, with a length of about 1.5 mm, may still be immature. Its body is divided into three tagmata. The cephalon, including five appendiculate segments, h a projecting forehead with a rostral spine and a small shield with a joint between fourth and fifth segments. Eyes are absent. The trunk is composed of seven annular segments, the anterior two with appendages. The caudal end is a long pleotelson-like segment with the anus on its ventral surface. There are seven pairs of appendages: uniramous antennulae, composed of few tubular podomeres; four pairs of biramous postantennular, almost homeomorphic cephalic appendages; two pairs on the trunk, the anterior pair being similar to the cephalic appendages except for the exopodite, the posterior being much smaller, uniramous and apparently rudimentary. Martinssonia was probably benthic, feeding on detritic particles which it stirred up from the bottom. Besides various crustacean-like features, the new form reveals structures different from Crustacea as well as from all other known arthropodan groups. Martinssonia presumably is a descendant of an euarthropodan group, originating from the crustacean branch long before reaching the eucrustacean level of evolution.     

The metatrochophore of a deep-sea hydrothermal vent vestimentiferan (Polychaeta: Siboglinidae)

Vestimentiferans (Siboglinidae, Polychaeta) live as juveniles and adults in an obligate mutualistic association with thiotrophic bacteria. Since their development is aposymbiotic, metatrochophores of vestimentiferans from the East Pacific Rise colonizing deep-sea hydrothermal vents are infected with the specific symbiont, develop the trophosome, and reduce their digestive system. To gain insight into the anatomy and ultrastructure and to compare this stage with metatrochophores from other siboglinids, we serial sectioned and reconstructed three specimens using light and transmission electron microscopy. The metatrochophore was composed of a prostomium, a small peristomium, two chaetigers (or two chaetigers and one additional segment without chaetae), and a minute pygidium. A digestive system and an intraepidermal nervous system were developed. Larval organs such as the prototroch, the neurotroch, and an apical organ were present, along with juvenile/adult organs such as tentacles, uncini, pyriform glands, and the anlage of the nephridial organ. We propose that in vestimentiferans, the vestimentum is the head arising from the prostomium, peristomium, and the anterior part of the first chaetiger. In frenulates, in contrast, the head is composed on the one hand of the cephalic lobe arising from the prostomium and on the other of the forepart developing from the peristomium and the anterior part of the first chaetiger. In frenulates the muscular septum between the forepart and trunk develops later than the first two chaetigers. Since this septum has no counterpart in vestimentiferans, the forepart-trunk border of frenulates is not considered homologous with the vestimentum-trunk border in vestimentiferans. The obturacular region in vestimentiferans does not appear to be a body region but rather the head appendages arising from the first chaetiger. In contrast, the tentacles in frenulates are prostomial head appendages. In both taxa, the trunk is the posterior part of the first chaetiger, and the opisthosoma is the following chaetigers and the pygidium. Comparisons with other polychaetes suggest that two larval segments are autapomorphic for the monophyletic Siboglinidae.     

<Emphasis Type="Italic">Petasiger islandicus</Emphasis> n. sp. (Digenea: Echinostomatidae) in the horned grebe <Emphasis Type="Italic">Podiceps auritus</Emphasis> (L.) (Aves: Podicipedidae) from Iceland

Petasiger islandicus n. sp. is described and figured from a demographically isolated population of the horned grebe Podiceps auritus auritus (L.) in Lake Myvatn (Iceland). This new species belongs to the group of species with 19 collar spines which possess a large elongate-oval cirrus-sac, well-developed pars prostatica and massive bulb-like cirrus. Within this group, P. islandicus appears most similar to P. oschmarini Kostadinova & Gibson, 1998, a form with similar body dimensions described from the same host, but differs in having a larger head collar, collar spines, oral sucker, pharynx, testes and sucker-width ratio, and a smaller cirrus-sac, cirrus and eggs. Two Nearctic species resemble P. islandicus in general morphology but differ as follows: P. pseudoneocomense Bravo-Hollis, 1969 has a larger body and collar width, notably shorter collar spines, smaller testes and sucker-width ratio, and a shorter but much wider cirrus-sac which is also smaller relative to the ventral sucker and almost entirely anterior to it; and P. caribbensis Nassi, 1980 has a smaller body, shorter collar spines and a seminal vesicle which is small in relation to the cirrus-sac, vitelline fields reaching anteriorly to the level of the genital pore and the intestinal bifurcation is located more anteriorly.     

Monogeneans from Clarias (Siluriformes, Clariidae) in Cameroon. II. Description of three new species of Birgiellus n gen (Dactylogyridea, Ancyrocephalidae) in the Nyong Basin

A study of monogenean gill parasites from three species of the genus Clarias Scopoli, 1777 (Clariidae), namely Clarias camerunensis L?nnberg, 1895, C. jaensis Boulenger, 1909 and C. pachynema Boulenger, 1903, from the Nyong Basin (Cameroon) revealed the presence of three new monogenean species of the new genus Birgiellus, namely Birgiellus mutatus n. sp. from C. pachynema, B. calaris n. sp. from C. jaensis and B. kellensis n. sp. from C. camerunensis. The genus Birgiellus differs from the genus Quadriacanthus by the morphology of the ventral bar composed of a single piece (two distinct in Quadriacanthus) and the size of the uncinuli IV, which are not much different from the others (longest in Quadriacanthus). Birgiellus calaris differs from B. mutatus by its ventral anchors longer and larger, the morphology of the ventral bar with a short incision between the two branches, and a long and trapezoid handle, the size of the sclerotised structures of the male and female copulatory organs, the larger thickness of the hook in the male accessory piece, the latter having also a heel. Birgiellus kellensis is closer to B. calaris but can be distinguished by the small size of its dorsal and ventral anchors, its transverse bars, male copulatory organ, and the accessory piece, which also has not a heel but a secondary blade. According to the clause 8.5.2 of the International Zoological Code of Nomenclature (1999) the genus Birgiellus and the species B. mutatus and B. calaris, respectively, replace Claridectes, C. clarisa and C. alacris previously described by Birgi (1987), but whose specimens were not deposited in a museum. All the three taxa described exhibit a strict (oioxenous) host specificity.