The systematics of Lobophora (Dictyotales,Phaeophyceae) in the western Atlantic and eastern Pacific oceans: eight new species

Lobophora is a common tropical to temperate genus of brown algae found in a plethora of habitats including shallow and deep‐water coral reefs, rocky shores, mangroves, seagrass beds, and rhodoliths beds. Recent molecular studies have revealed that Lobophora species diversity has been severely underestimated. Current estimates of the species numbers range from 100 to 140 species with a suggested center of diversity in the Central Indo‐Pacific. This study used three molecular markers (cox3, rbcL, psbA), different single‐marker species delimitation methods (GMYC, ABGD, PTP), and morphological evidence to evaluate Lobophora species diversity in the Western Atlantic and the Eastern Pacific oceans. Cox3 provided the greatest number of primary species hypotheses(PSH), followed by rbcL and then psbA. GMYC species delimitation analysis was the most conservative across all three markers, followed by PTP, and then ABGD. The most informative diagnostic morphological characters were thallus thickness and number of cell layers in both the medulla and the dorsal/ventral cortices. Following a consensus approach, 14 distinct Lobophora species were identified in the Western Atlantic and five in the Eastern Pacific. Eight new species from these two oceans were herein described: L. adpressa sp. nov., L. cocoensis sp. nov., L. colombiana sp. nov., L. crispata sp. nov., L. delicata sp. nov., L. dispersa sp. nov., L. panamensis sp. nov., and L. tortugensis sp. nov. This study showed that the best approach to confidently identify Lobophora species is to analyze DNA sequences (preferably cox3 and rbcL) followed by comparative morphological and geographical assessment.     

A revision of the genus Cryptonemia (Halymeniaceae,Rhodophyta) in Bermuda,western Atlantic Ocean,including five new species and C. bermudensis (Collins & M. Howe) comb. nov.

Cryptonemia specimens collected in Bermuda over the past two decades were analysed using gene sequences encoding the large subunit of the nuclear ribosomal DNA and the large subunit of RuBisCO as genetic markers to elucidate their phylogenetic positions. They were additionally subjected to morphological assessment and compared with historical collections from the islands. Six species are presently found in the flora including C. bermudensis comb. nov., based on Halymenia bermudensis, and the following five new species: C. abyssalis, C. antricola, C. atrocostalis, C. lacunicola and C. perparva. Of the eight species known in the western Atlantic flora prior to this study, none is found in Bermuda. Specimens reported in the islands in the 1900s attributed to C. crenulata and C. luxurians are representative of the new species, C. antricola and C. atrocostalis, respectively.     

PHYLOGENETIC RELATIONSHIPS WITHIN THE GENUS HYPNEA (GIGARTINALES,RHODOPHYTA), WITH A DESCRIPTION OF H. CAESPITOSA SP. NOV.1

Species discrimination within the gigartinalean red algal genus Hypnea has been controversial. To help resolve the controversy and explore phylogeny within the genus, we determined rbcL sequences from 30 specimens of 23 species within the genus, cox1 from 22 specimens of 10 species, and psaA from 16 species. We describe H. caespitosa as a new species characterized by a relatively slender main axis; a pulvinate growth habit with entangled, anastomosing, and subulate uppermost branches; and unilaterally borne tetrasporangial sori. The new species occurs in the warm waters of Malaysia, the Philippines, and Singapore. The phylogenetic trees of rbcL, psaA, and cox1 sequences showed a distant relationship of H. caespitosa to H. pannosa J. Agardh from Baja California and the marked differentiation from other similar species. The rbcL + psaA tree supported monophyly of the genus with high bootstrap values and posterior probabilities. The analysis revealed three clades within the genus, corresponding to three sections, namely, Virgatae, Spinuligerae, and Pulvinatae first recognized by J. G. Agardh. Exceptions were H. japonica T. Tanaka in Pulvinatae and H. spinella (C. Agardh) Kütz. in Spinuligerae.     

Lobophora (Dictyotales) Species Richness,Ecology and Biogeography Across the North-Eastern Atlantic Archipelagos and Description of Two New Species1

The brown alga Lobophora (Dictyotales, Phaeophyceae) is an important macroalga in the North-eastern Atlantic archipelagos (i.e., Macaronesia). Notably in the Canaries it can dominate benthic assemblages. While the genus has been the subject of several ecological studies in the Canaries, no study has yet been conducted to assess species-level diversity of Lobophora in Macaronesia. We reassessed the diversity of Lobophora in Macaronesia, reporting the presence of seven species (L. caboverdeana sp. nov., L. canariensis, L. dagamae sp. nov., L. delicata, L. dispersa, L. littlerorum, and L. schneideri). Lobophora spp. from Macaronesia are morphologically and ecologically distinguishable. In the Canaries, L. schneideri dominates the photophilic assemblages from the intertidal to 20-30 m depth. Lobophora dagamae sp. nov. grows in less illuminated shallow habitats, and replaces L. schneideri from 30 to ~80 m. Lobophora canariensis also has a wide vertical distribution, from the intertidal to deep waters, while L. delicata, L. dispersa and L. littlerorum grow in shallow waters. The dominance of species with an upright habit versus prostrate or crustose species may be mediated by the pressure of herbivores. Four species have an amphi-Atlantic distribution: L. littlerorum, L. canariensis, L. delicata, and L. schneideri. Lobophora schneideri and L. delicata are furthermore distributed in the Mediterranean Sea. By sampling a pivotal region in the Atlantic, this study significantly improves our knowledge of Lobophora biogeography in the Atlantic Ocean. Macaronesia constitutes a species–poor region for Lobophora where no diversification events occurred, and a region of overlap between the Greater Caribbean and the Indo-Pacific.     

Diversity,Ecology, Biogeography,and Evolution of the Prevalent Brown Algal Genus Lobophora in the Greater Caribbean Sea,Including the Description of Five New Species1

Distributed in tropical and warm-temperate waters worldwide, Lobophora species are found across the Greater Caribbean (i.e., Caribbean sensu stricto, Gulf of Mexico, Florida, the Bahamas, and Bermuda). We presently discuss the diversity, ecology, biogeography, and evolution of the Greater Caribbean Lobophora species based on previous studies and an extensive number of samples collected across the eastern, southern, and to a lesser extent western Caribbean. A total of 18 Lobophora species are now documented from the Greater Caribbean, of which five are newly described (L. agardhii sp. nov., L. dickiei sp. nov., L. lamourouxii sp. nov., L. richardii sp. nov., and L. setchellii sp. nov.). Within the Greater Caribbean, the eastern Caribbean and the Central Province are the most diverse ecoregion and province (16 spp.), respectively. Observed distribution patterns indicate that Lobophora species from the Greater Caribbean have climate affinities (i.e., warm-temperate vs. tropical affinities). In total, 11 Lobophora species exclusively occur in the Greater Caribbean; six are present in the western Atlantic; two in the Indo-Pacific; and one in the eastern Pacific. Biogeographic analyses support that no speciation occurred across the Isthmus of Panama, and that the Greater Caribbean acted as a recipient region for species from the Indo-Pacific and as a region of diversification as well as a donor region to the North-eastern Atlantic. The Greater Caribbean is not an evolutionary dead end for Lobophora, but instead generates and exports diversity. Present results illustrate how sampling based on DNA identification is reshaping biogeographic patterns, as we know them.     

New species, observations, and a list of new records of brown algae (Phaeophyceae) from the Hawaiian Islands

Two new species of brown algae (Phaeophyceae), Padina moffittiana Abbott et Huisman, sp. nov. and Cutleria irregularis Abbott et Huisman, sp. nov., are described from the Hawaiian Islands (between 19°04′N, 155°35′W and 28°25′N, 178°20′W). In addition, the new combination Cutleria canariensis is proposed for Aglaozonia canariensis. New observations are presented on Nereia intricata Yamada, a species described 67 years ago and known only from its type specimen. New records of a further 14 species are given for the Hawaiian Islands. These 17 taxa bring the total number of species of brown algae recorded for the Hawaiian Islands to 55, an increase of 28%. Of the 15 new records, two are recent ‘accidental’ introductions: Dictyota flabellata (Collins) Setchell et Gardner and Sargassum muticum (Yendo) Fensholt from California. Six records are notable because of their great distances from previously known collections: Nereia intricata Yamada from the Ryukyu Is., Japan; Discosporangium mesarthrocarpum (Meneghini) Hauck, from the Adriatic, Mediterranean, warm Atlantic and southern Australia; Distromium flabellatum Womersley, Spatoglossum macrodontum J. Agardh, and Sporochnus moorei Harvey, from Australia; Desmarestia ligulata (Lightfoot) Lamouroux from temperate and colder waters in the Pacific and Atlantic. A comparison with some Japanese species of Padina confirms that Padina japonica Yamada should be subsumed with Padina sanctae‐crucis Børgesen, as proposed earlier.     

Cladosiphon takenoensis sp. nov. (Ectocarpales s.l., Phaeophyceae) from Japan

The new brown algal species Cladosiphon takenoensis H. Kawai (Chordariaceae, Ectocarpales s.l.) is described from Takeno, Hyogo, Japan based on morphology and DNA sequences. The species is a spring annual, growing on subtidal rocks at more or less exposed sites. It resembles C. umezakii in its gross morphology, and the two often grow together, but is distinguishable from C. umezakii in having a more hairy appearance. Cladosiphon takenoensis has a slimy, cylindrical, multiaxial and sympodial erect thallus, branching once to twice, and is provided with long assimilatory filaments (up to 1.8 mm long, composed of up to 100 cells). Unilocular zoidangia are formed on the basal part of assimilatory filaments. The species is genetically most related to C. umezakii and has the same basic thallus structures, but differs from C. umezakii and other Cladosiphon species in lacking phaeophycean hairs and plurilocular zoidangia of the assimilatory filaments. DNA sequences of the mitochondrial cox1 and cox3, chloroplast atpB, psaA, psbA and rbcL genes and the nuclear rDNA ITS2 region support the distinctness of the species. The genus Cladosiphon was paraphyletic in our analyses because the clades of C. okamuranus/C. zosterae and C. takenoensis/C. umezakii were split by Mesogloia vermiculata. However, since the genus‐level taxonomy of Chordariaceae needs considerable revision, we suspend the genus‐level taxonomy of the new species, and tentatively describe it as C. takenoensis.     

Tinocladia sanrikuensis sp. nov. (Ectocarpales s.l., Phaeophyceae) from Japan

The new species Tinocladia sanrikuensis sp. nov. H.Kawai, K.Takeuchi & T.Hanyuda (Ectocarpales s.l., Phaeophyceae) is described from the Pacific coast of the Tohoku region, northern Japan based on morphology and DNA sequences. The species is a spring–summer annual growing on lower intertidal to upper subtidal rocks and cobbles on relatively protected sites. T. sanrikuensis has a slimy, cylindrical, multiaxial erect thallus, slightly hollow when fully developed, branching once to twice, and resembles T. crassa in gross morphology. The erect thalli are composed of a dense medullary layer, long subcortical filaments, and assimilatory filaments of 11–35 cells, up to 425 μm long and curved in the upper portion. Unilocular zoidangia are formed on the basal part of assimilatory filaments. The species is genetically most closely related to T. crassa and has the same basic thallus structures but differs in having thinner and longer assimilatory filaments. DNA sequences of the mitochondrial cox1 and cox3, chloroplast atpB, psaA, psbA and rbcL genes support the distinctness of this species.     

Delineation of Two Sibling Red Algal Species,Gracilaria Gracilis and Gracilaria Dura (Gracilariales,Rhodophyta), Using Multiple DNA Markers: Resurrection of the Species G. Dura Previously Described in the Northern Atlantic 200 Years Ago1

Molecular markers belonging to the three different genomes, mitochondrial (cox2‐cox3 spacer), plastid (rbcL), and nuclear (internal transcribed spacer [ITS] 2 region), were used to compare samples of the two morphologically related species Gracilaria gracilis (Stackh.) Steentoft, L. M. Irvine et Farnham and G. dura (C. Agardh) J. Agardh collected along Atlantic coasts. In northern Europe, the distinction between these two species is ambiguous, and they are currently recognized under the single name of G. gracilis. The low but congruent patterns of genetic divergence observed for markers of the three genomic compartments highly suggest that these two taxa correspond effectively to two different genetic entities as previously described 200 years ago, based on morphological traits. However, thanks to the combination of different DNA markers, occurrence of “incongruent” cytotypes (i.e., mitotypes of G. dura associated with chlorotypes of G. gracilis) in individuals collected from Brittany, suggests interspecific hybridization between the two sibling species studied.     

Phylogeography of the freshwater red alga Sirodotia (Batrachospermales,Rhodophyta) in Brazil

Considering the lack of knowledge on genetic variation on members of the freshwater red algal of the order Batrachospermales in tropical regions, phylogeographic patterns in Sirodotia populations were investigated using two mitochondrial regions: the cox2‐3 spacer and partial cox1 gene (barcode). Individuals identified as Sirodotia delicatula were analyzed from 14 stream segments across its distribution in Brazil. Phylogenetic analyses based on the ribulose‐1,5‐bisphosphate carboxylase/oxygenase large sub‐unit gene showed three clades, one representing S. delicatula, from all locations in southeastern Brazil and other regions from Brazil. The remaining samples formed two clades, which were highly divergent and distantly positioned from those of S. delicatula: 2.5–2.7% and 3.4–3.7%. This level of variation would warrant the species split of these taxa from mid‐western Brazil. A total of eight cox2‐3 spacer and nine cox1 haplotypes were observed among the 122 individuals studied. One location had two cox2‐3 haplotypes and three locations had two cox1 haplotypes; all others had a single dominant haplotype each. The existence of high intraspecific genetic variation among individuals of distinct locations (several haplotypes), but little variation within a location seems to be a pattern for the Batrachospermales. Haplotype networks showed low variation among the haplotypes from southeastern Brazil (10 locations with divergence of 0.3–1.1% for cox2‐3, 0.1–0.3% for cox1) and high variation among the haplotypes from the mid‐west region (four locations, 4.0–9.3% for cox2‐3, 6.2–8.4% for cox1). Thus, the present data clearly suggest the existence of cryptic species in Sirodotia in Brazil.     

A NEW AGAROPHYTE SPECIES,GELIDIUM EUCORNEUM SP. NOV. (GELIDIALES,RHODOPHYTA), BASED ON MOLECULAR AND MORPHOLOGICAL DATA1

Gelidium is an economically and ecologically important agar‐producing genus. Although the taxonomy of Gelidium has been the focus of many published studies, there is still a need to reevaluate species‐level diversity. Herein, we describe Gelidium eucorneum sp. nov. based on specimens collected off Geojedo on the southern coast of Korea. G. eucorneum is distinguished by cartilaginous thalli with brush‐like haptera, rhizoidal filaments concentrated in the medulla, and globose cytocarps that are horned with multiple determinate branchlets. The species occurs in wave‐exposed intertidal sites, sometimes in association with other mat‐forming algae. Phylogenetic analyses (rbcL, psaA, and cox1) reveal that G. eucorneum is unique and clearly distinct from other species of the genus. The clade containing Gelidium vagum and Acanthopeltis longiramulosa was resolved as a sister group to G. eucorneum. We suggest that the diverse morphologies of G. eucorneum, G. vagum, and Acanthopeltis developed from a common ancestor in East Asian waters. This study shows that even in well‐studied areas, more agarophyte species are to be added to the world inventory of red algae.     

Systematic revision of the genus Phycodrys (Delesseriaceae,Rhodophyta) from New Zealand,with the descriptions of three new species,P. novae-zelandiae sp. nov., P. franiae sp. nov. and P. adamsiae sp. nov.

Two species of Phycodrys, Phycodrys quercifolia (Bory) Skottsberg and Phycodrys profunda E.Y.Dawson were previously recorded from New Zealand. However, an examination of Phycodrys collections from the New Zealand region showed that all were morphologically different from P. quercifolia (Type locality: the Falkland Islands) and P. profunda (Type locality: CA, USA). RbcL sequence analyses established that the New Zealand Phycodrys species formed a natural assemblage within the genus, consisting of three new species: P. novae-zelandiae sp. nov., P. franiae sp. nov. and P. adamsiae sp. nov. Phycodrys novae-zelandiae is the largest of the three, up to 20 cm in height, with a distinct midrib and multicellular, opposite to subopposite lateral macroscopic veins. It has entirely monostromatic blades except near the midrib and veins, and its procarp contains a three-celled sterile group one (st1) and a one-celled sterile group two (st2). Phycodrys franiae was previously treated as a cryptic species among herbarium collections of P. ‘quercifolia’. It is smaller (4–11 cm high) with weakly developed midribs and veins, the blade is tristromatic throughout, except at the growing margins, and the procarp consists of a four-celled st1 and a two–three-celled st2. Phycodrys adamsiae, previously reported as P. profunda, is a small decumbent or prostrate plant, 1–8 cm long, with a midrib and inconspicuous lateral veins. The blades are tristromatic with serrated margins, two–four-celled surface spines and multicellular marginal holdfasts that differ from those of Californian specimens. The tetrasporangia are borne on marginal bladelets. Phylogenetic analyses place the New Zealand species in a separate group that is distantly removed from most other Phycodrys species.     

GRACILARIA VERMICULOPHYLLA (RHODOPHYTA,GRACILARIALES) IN THE VIRGINIA COASTAL BAYS,USA: COX1 ANALYSIS REVEALS HIGH GENETIC RICHNESS OF AN INTRODUCED MACROALGA

Gracilaria vermiculophylla (Ohmi) Papenfuss is an invasive alga that is native to Southeast Asia and has invaded many estuaries in North America and Europe. It is difficult to differentiate G. vermiculophylla from native forms using morphology and therefore molecular techniques are needed. In this study, we used three molecular markers (rbcL, cox2‐cox3 spacer, cox1) to identify G. vermiculophylla at several locations in the western Atlantic. RbcL and cox2‐cox3 spacer markers confirmed the presence of G. vermiculophylla on the east coast of the USA from Massachusetts to South Carolina. We used a 507 base pair region of cox1 mtDNA to (i) verify the widespread distribution of G. vermiculophylla in the Virginia (VA) coastal bays and (ii) determine the intraspecific diversity of these algae. Cox1 haplotype richness in the VA coastal bays was much higher than that previously found in other invaded locations, as well as some native locations. This difference is likely attributed to the more intensive sampling design used in this study, which was able to detect richness created by multiple, diverse introductions. On the basis of our results, we recommend that future studies take differences in sampling design into account when comparing haplotype richness and diversity between native and non‐native studies in the literature.     

Collections from the mesophytic zone off Bermuda reveal three species of Kallymeniaceae (Gigartinales,Rhodophyta) in genera with transoceanic distributions

A molecular survey of red algae collected by technical divers and submersibles from 90 m in the mesophotic zone off the coast of Bermuda revealed three species assignable to the Kallymeniaceae. Two of the species are representative of recently described genera centered in the western Pacific in Australia and New Zealand, Austrokallymenia and Psaromenia and the third from the Mediterranean Sea and the eastern Atlantic, Nothokallymenia. A phylogenetic analysis of concatenated mitochondrial (COI‐5P) and chloroplast (rbcL) genes, as well as morphological characteristics, revealed that two are shown to be new species with distant closest relatives (N. erosa and Psaromenia septentrionalis), while the third represents a deep water western Atlantic species now moved to an Australasian genus (A. westii).     

A molecular evaluation of the Liagoraceae sensu lato (Nemaliales,Rhodophyta) in Bermuda including Liagora nesophila sp. nov. and Yamadaella grassyi sp. nov.

We have undertaken a comprehensive, molecular‐assisted alpha‐taxonomic examination of the rhodophyte family Liagoraceae sensu lato, a group that has not previously been targeted for molecular studies in the western Atlantic. Sequence data from three molecular markers indicate that in Bermuda alone there are 10 species in nine different genera. These include the addition of three genera to the flora — Hommersandiophycus, Trichogloeopsis, and Yamadaella. Liagora pectinata, a species with a type locality in Bermuda, is phylogenetically allied with Indo‐Pacific species of Hommersandiophycus, and the species historically reported as L. ceranoides for the islands is morphologically and genetically distinct from that taxon, and is herein described as L. nesophila sp. nov. Molecular sequence data have also uncovered the Indo‐Pacific L. mannarensis in Bermuda, a long‐distance new western Atlantic record. DNA sequences of Trichogloeopsis pedicellata from the type locality (Bahamas) match with local specimens demonstrating its presence in Bermuda. We described Yamadaella grassyi sp. nov. from Bermuda, a species phylogenetically and morphologically distinct from the generitype, Y. caenomyce of the Indo‐Pacific. Our data also indicated a single species each of Ganonema, Gloiocallis, Helminthocladia, Titanophycus, and Trichogloea in the flora.     

rbcL gene sequences reveal relationships among north-east Pacific species of Porphyra (Bangiales, Rhodophyta) and a new species, P. aestivalis

Phylogenetic analyses of the rbcL (chloroplast Rubisco large subunit) gene from 23 newly sequenced species of Porphyra, primarily from the north‐east Pacific, one Bangia and previously published sequences from both genera resolve relationships among most species of Porphyra and reveal five clades of species with Porphyra‐type morphologies among a number of Bangia lineages: (1) P. papenfussii V. Krishnam; (2) P. mumfordii S. C. Lindstrom et K. M. Cole and P. rediviva Stiller et Waaland together with a group of north Atlantic species, including the type of the genus, P. purpurea (Wahl‐enb.) C. Agardh; (3) P. cuneiformis (Setch. et Hus) V. Krishnam., P. occidentalis Setch. et Hus, P. schizo‐phylla Hollenb., and P. variegata (Kjellm.) Kjellm. and their Atlantic sibling species, all distromatic; (4) P. aestivalis sp. nov. and its north Atlantic sibling, P. birdiae C. D. Neefus et A. C. Mathieson; and (5) a speciose clade containing both Pacific and Atlantic representatives. Close relationships are confirmed between sibling species previously identified by iso‐zymes, morphology and chromosomal features. The morphologically similar dioecious P. pseudolanceolata V. Krishnam., P. conwayae (S. C. Lindstrom et K. M. Cole) stat. nov., and P. lanceolata (Setch. et Hus) G. M. Smith occur in a strongly supported subclade in clade 5 together with the monoecious P. fallax S. C. Lindstrom et K. M. Cole. Results presented here highlight the need for intensive taxon sampling and for examination of different parts of the genome to understand more fully relationships among species and higher level taxa in the Bangiales.     

Genetic and morphological variation in an ecosystem engineer,Lithophyllum byssoides (Corallinales,Rhodophyta)

Lithophyllum byssoides is a common coralline alga in the intertidal zone of Mediterranean coasts, where it produces biogenic concretions housing a high algal and invertebrate biodiversity. This species is an ecosystem engineer and is considered a target for conservation efforts, but designing effective conservation strategies currently is impossible due to lack of information about its population structure. The morphological and molecular variation of L. byssoides was investigated using morphoanatomy and DNA sequences (psbA and cox2,3) obtained from populations at 15 localities on the Italian and Croatian coasts. Lithophyllum byssoides exhibited a high number of haplotypes (31 psbA haplotypes and 24 cox2,3 haplotypes) in the central Mediterranean. The psbA and cox2,3 phylogenies were congruent and showed seven lineages. For most of these clades, the distribution was limited to one or a few localities, but one of them (clade 7) was widespread across the central Mediterranean, spanning the main biogeographic boundaries recognized in this area. The central Mediterranean populations formed a lineage separate from Atlantic samples; psbA pair‐wise divergences suggested that recognition of Atlantic and Mediterranean L. byssoides as different species may be appropriate. The central Mediterranean haplotype patterns of L. byssoides were interpreted as resulting from past climatic events in the hydrogeological history of the Mediterranean Sea. The high haplotype diversity and the restricted spatial distribution of the seven lineages suggest that individual populations should be managed as independent units.     

Etheliaceae fam. nov. (Gigartinales,Rhodophyta), with a clarification of the generitype of Ethelia and the addition of six novel species from warm waters

Based upon COI‐5P, LSU rDNA, and rbcL sequence data and morphological characteristics, six new members of the noncalcified crustose genus of red algae Ethelia are described in a new family, Etheliaceae (Gigartinales), sister to the recently described Ptilocladiopsidaceae. The novel species are described from subtropical to tropical Atlantic and Indo‐Pacific Ocean basins; E. mucronata sp. nov. and E. denizotii sp. nov. from southern and northern Western Australia respectively, E. wilcei sp. nov. from the Cocos (Keeling) Islands of Australia, E. suluensis sp. nov. from the Philippines, E. umbricola sp. nov. from Bermuda and E. kraftii sp. nov. from Lord Howe Island, Australia. The generitype, Ethelia biradiata, originally reported from the Seychelles, Indian Ocean, is added to the Western Australian flora.     

Urstylidae – a new family of abyssal isopods (Crustacea: Asellota) and its phylogenetic implications

We report three new species of isopod crustaceans that belong to a rare higher taxon of asellote Isopoda. This taxon does not fit into current classifications. The isopods occurred in abyssal soft sediments, near manganese nodules, and in the vicinity of hydrothermal vents. Given their wide spatial occurrence across the Atlantic and Pacific Oceans, a cosmopolitan distribution is assumed. A cladistic analysis revealed a close relationship with the Macrostylidae, a common representative of the deep‐sea macrofauna. Analyses of character evolution across the Janiroidea showed sufficient synapomorphies to justify the erection of U rstylis gen. nov. and the new family Urstylidae based on the three new species. All taxa are described in this paper. Urstylidae is characterized, amongst other apomorphies, by an elongate habitus with spade‐like head; uropods are long, styliform; one pleonite is free; antennal merus and carpus are relatively short; the first pereopod is carpo‐propodosubchelate, and more robust and shorter than pereopod II. Several characters, such as the pereopods’ posterior scale‐like claw that basally encloses the distal sensilla may be interpreted as ancestral when compared to the situation in the highly derived Macrostylidae. © 2014 The Linnean Society of London     

ALGAE FROM CABO FRIO UPWELLING AREA. 2. GELIDIOCOLAX PUSTULATA (GELIDIACEAE,RHODOPHYTA): AN UNUSUAL NEW PUTATIVE PARASITIC SPECIES1

A new species of Gelidiocolax Gardner, G. pustulata Oliveira and Yoneshigue, is described in the tropical western Atlantic from Brazil. The species usually grows on the basal portion of the main axis of Pterocladia capillacea (Gmelin) Bornet et Thuret. Abundant material was collected mainly from November to March at Cabo Frio Island, in the northeast part of the State of Rio de Janeiro, a marine area well known for its upwelling. Infection by the putative parasite seems to damage the host tissue, stimulating the development of a “gall-like” structure that leads to the outgrowth of adventitious branches. The new species has the vegetative features and reproductive structures of the genus Gelidiocolax. It can be distinguished from the other Gelidiocolax species mainly on the basis of its position on the host, size of pustula, the tetrasporangia and the development of spermatangia. Studies of this new taxon support the placement of Gelidiocolax in the Gelidiaceae and not the Choreocolacaceae, as has been suggested in the literature.