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  • The Lusitania Province as a center of diversification: the phylogeny of the genus Microlipophrys (Pisces: Blenniidae)
    Publication . Martínez-Levy, Gabriela A.; Wirtz, Peter; Floeter, S. R.; Almada, V. C.
    The Lusitania Province has been considered a transition zone between the Atlantic northern cold waters and Tropical warm waters. Tropical species have expanded their ranges during warm periods and either retreated during cold periods or survived in local refuges. Successive waves of dispersion into this Province could have favored diversification through geographic isolation. Taxa that remained in this large Province may also have diversified in loco. We analyzed molecular markers of the genus Microlipophrys (family Blenniidae) that confirm the validity of this genus and of the seven recognized species. Microlipophrys and its sister clade apparently originated within Lusitania and dispersed into the tropics at a later stage. (C) 2010 Elsevier Inc. All rights reserved.
  • The fishes of ascension Island, central Atlantic Ocean - new records and an annotated checklist
    Publication . Wirtz, Peter; Bingeman, Jane; Bingeman, John; Fricke, Ronald; Hook, Timothy J.; Young, Jimmy
    A checklist of the fishes of Ascension Island is presented. The species Rhincodon typus, Alopias superciliosus, Isurus oxyrinchus, Carcharhinus obscurus, Galeocerdo cuvier, Sphyrna lewini, Hexanchus griseus, Manta birostris, Gymnothorax vicinus, Hippocampus sp., Epinephelus itajara, Cookeolus japonicus, Apogon pseudomaculatus, Phaeoptyx pigmentaria, Remora albescens, Caranx bartholomaei, Carangoides ruber, Decapterus tabl, Seriola dumerili, Thalassoma sanctaehelenae, Cryptotomus sp., Ruvettus pretiosus, Acanthocybium solandri, Auxis rochei, Auxis thazard, Euthynnus alletteratus, Katsuwonus pelamis, Thunnus alalunga, Thunnus obesus, Xiphias gladius, Istiophorus platypterus, Kajikia albida, Makaira nigricans, Tetrapturus pfluegeri, Hyperoglyphe perciformis, Schedophilus sp., Cantherhines macrocerus, Sphoeroides pachygaster and Diodon eydouxii are recorded for the first time from Ascension Island. We have recognized two previous records as identification errors and indicate 11 other records as doubtful. Including the 40 new records, we now list 173 fish species from Ascension Island, of which 133 might be considered 'coastal fish species'. Eleven of these (8.3%) appear to be endemic to the island and a further 16 species (12%) appear to be shared endemics with St Helena Island.
  • Observations on some interesting coastal Crustacea Decapoda from the Azores, with a key to the genus Eualus Thallwitz, 1892 in the Northeastern Atlantic and the Mediterranean
    Publication . Udekem d'Acoz, Cédric d’; Wirtz, Peter
    Records of several rare or interesting Crustacea Decapoda from the Azores are presented in the present paper. Periclimenes sagittifer and Athanas nitescens are recorded for the first time in the archipelago. Periclimenes sagittifer was found on various hydroids and the antipatharian Antipathes wollastoni, some juveniles being also found amongst algae. Athanas nitescens was encountered free-living and in a shell inhabited by the hermit crab Dardanus calidus. Comparative illustrations are given for Azorean Periclimenes sagittifer and French specimens. New characters are proposed to distinguish Eualus cranchii, E. drachi, E. occultus and E. pusiolus, and a key to Northeastern Atlantic and Mediterranean Eualus species is provided. Azorean specimens of Hippolyte varians prove to be especially small and slender, whilst Azorean Stenopus spinosus may have red, white or even proximally red and distally white antennae. The association between the hermit crab Nematopagurus longicornis and the antipatharian Antipathes wollastoni is recorded for the first time. A possibly undescribed Macropodia species is here recorded and illustrated as Macropodia sp., as only juvenile and damaged adult specimens were found. Azorean Portunus hastatus prove to be much less pubescent than their Mediterranean counterparts, and detailed drawings are given for this common but rarely comprehensively illustrated species.
  • On a collection of hydroids (Cnidaria, Hydrozoa) from the Madeira archipelago
    Publication . Wirtz, Peter
    Hydroids were collected from Madeira and Porto Santo Islands (eastern temperate Atlantic Ocean) by SCUBA diving over a depth range from 0 to 62 m, as well as by two trawls off the city of Funchal, at depths of 60 and 100 m. A preliminary list of 53 identified species from 33 genera and 17 families is given and comments are made on some of them. Eight of them could not be determined to species level because they either lacked gonophores or the medusa stage is necessary for identification. An undescribed species (genus Sertularella) will be described in a separate publication. Additional species have been sent to hydroid specialists, and their identifications are pending.
  • Comment on 'Island biogeography: patterns of marine shallow-water organisms' by Hachich et al., Journal of Biogeography (2015)
    Publication . Ávila, Sérgio P.; Cordeiro, Ricardo; Haroun, Ricardo; Wirtz, Peter
    In a recent article, Hachich et al. ( 2015, Journal of Biogeography, 42, 1871-1882) studied the large-scale biogeographical patterns of the species-area, species-island age and species-isolation relationships associated with marine shallow-water groups ( reef fish, gastropods and seaweeds) from 11 Atlantic archipelagos. We here express our concerns regarding the data accuracy used to compute the different models that tested the null hypothesis of species richness being independent of the selected variables. In our commentary, we focus mainly on the use of out-of-date checklists of gastropod and seaweed species from different archipelagos, but we also point out inaccuracies in some island age estimates and explain our disagreement with the use of the 200 m depth limit for the shallow-water gastropods and seaweeds.
  • Heteromysis sabelliphila sp. nov. (Mysida, Mysidae, Heteromysinae) in facultative association with sabellids from the Cape Verde Islands (subtropical N.E. Atlantic)
    Publication . Wittmann, Karl J.; Wirtz, Peter
    A survey of crustaceans associated with benthic invertebrates in near-shore habitats at islands of the Cape Verde archipelago yielded a new species belonging to the genus Heteromysis, subgenus Olivemysis: H. sabelliphila sp. nov. shows a non-obligatory association with the sabellid polychaete Branchiomma nigromaculatum only during the night. This is the first documented mysid-polychaete association. The mysids apparently took particles collected by the polychaete, suggesting a kleptoparasitic interspecific relationship. A set of three specifically modified setae on the antennular trunk is shared by the new species with two Heteromysis species from Madeira (subtropical N. E. Atlantic), suggesting a close morphological relationship within the subgenus Olivemysis: with H. wirtzi, commensal of the sea anemone Telmatactis cricoides, and with H. dardani, commensal of the hermit crab Dardanus calidus. A key to the Heteromysinae of the E. Atlantic and Mediterranean is given.
  • A new species of Corcyrogobius (Teleostei: Gobiidae) from Ile de Ngor, Senegal
    Publication . Kovacic, Marcelo; Wirtz, Peter; Schliewen, Ulrich K.
    Corcyrogobius pulcher sp. nov. is described from off Ile de Ngor. Dakar, Senegal. Corcyrogobius pulcher is distinguished from its two congeners by having the rear edge of the jaws ending posteriorly below mideye, second dorsal fin 1/9, pectoral fin rays 17, pelvic fins oval or truncated posteriorly, scales in lateral series 26-27, anterior oculoscapular head canal with pore beta, suborbital row b of sensory papillae anteriorly beginning below vertical of posterior edge of eye, dark vertical caudal bar, branchiostegal membrane without intense dark spot, cheek with two oblique whitish stripes, the first going from the eye downwards and forward to the posterior jaws, the second on the preopercular, alternating with brown oblique stripe going from behind the eye downwards and forward across the cheek. Furthermore, mitochondrial COI-barcoding data unambiguously support the species-level distinctiveness of the three Corcyrogobius species. A key to the species of Corcyrogobius is provided.
  • New records of marine invertebrates from Ascension Island (central Atlantic)
    Publication . Brown, J.; Downes, K.; Mrowicki, R.J.; Nolan, E.L.; Richardson, A.J.; Swinnen, F.; Wirtz, Peter
    The sea anemone Telmatactis forskalii, the zoanthid Isaurus tuberculatus, the nemertine Baseodiscus delineatus, the echinoderms Ophiocoma wendtii and Mithrodia clavigera, the molluscs Colubraria canariensis, Glyphepithema turtoni, Tonna pennata, Trivia candidula, Melanella eburnea, Melanella n.sp., Echineulima leucophaes, Stylocheilus striatus, Limaria hians, Pteria hirundo and Callistoctopus macropus, and the crustaceans Tetraclitella sp., Oxynaspis celata, Thor amboinensis and Parribacus antarcticus are recorded from Ascension Island for the first time. A new depth record is given for the sea anemone Telmatactis cricoides. An undescribed shrimp species of the genus Lysmata and the shrimp Lysmata moorei were observed to clean fish at night.
  • New records of marine invertebrates from the coast of Senegal
    Publication . Wirtz, Peter
    During dives at the coast of Senegal, in the vicini-ty of NGor Island, several marine invertebrate species were observed that apparently have not yet been recorded from this area.
  • Restructuring of the ‘Macaronesia’ biogeographic unit: a marine multi-taxon biogeographical approach
    Publication . Freitas, Rui; Romeiras, Maria; Silva, Luís; Cordeiro, Ricardo; Madeira, Patrícia; González, José Antonio; Wirtz, Peter; Falcón, Jesús M.; Brito, Alberto; Floeter, Sergio R.; Afonso, Pedro; Porteiro, Filipe; Viera-Rodríguez, María Ascensión; Neto, Ana Isabel; Haroun, Ricardo; Farminhão, João N. M.; Rebelo, Ana Cristina; Baptista, Lara; Melo, Carlos S.; Martínez, Alejandro; Núñez, Jorge; Berning, Björn; Johnson, Markes E.; Ávila, Sérgio P.
    The Azores, Madeira, Selvagens, Canary Islands and Cabo Verde are commonly united under the term "Macaronesia". This study investigates the coherency and validity of Macaronesia as a biogeographic unit using six marine groups with very different dispersal abilities: coastal fishes, echinoderms, gastropod molluscs, brachyuran decapod crustaceans, polychaete annelids, and macroalgae. We found no support for the current concept of Macaronesia as a coherent marine biogeographic unit. All marine groups studied suggest the exclusion of Cabo Verde from the remaining Macaronesian archipelagos and thus, Cabo Verde should be given the status of a biogeographic subprovince within the West African Transition province. We propose to redefine the Lusitanian biogeographical province, in which we include four ecoregions: the South European Atlantic Shelf, the Saharan Upwelling, the Azores, and a new ecoregion herein named Webbnesia, which comprises the archipelagos of Madeira, Selvagens and the Canary Islands.