ARQ - Life and Marine Sciences
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- Acoetidae (Annelida, Polychaeta) from the Iberian Peninsula, Madeira and Canary islands, with description of a new speciesPublication . Palmero, Ana M.; Martínez, Alejandro; Brito, María del Carmen; Núñez, JorgeSix species of acoetid polychaetes are reported from the Iberian Peninsula and Macaronesia: Euarche tubifex Ehlers, 1887, Euarche cristata Núñez, n. sp., Eupanthalis kinbergi McIntosh, 1876, Eupolyodontes gulo (Grube, 1855), Polyodontes maxillosus (Ranzani, 1817), and Panthalis oerstedi (Kinberg, 1856). Material was collected during several sublittoral benthic surveys. Descriptions, figures, and a key for the six species are included. The new species Euarche cristata is characterized by its prostomium with cristate or serrated posterior margin.
- Acoustic tag retention of the Mediterranean slipper lobster Scyllarides latus (Latreille, 1802) in the AzoresPublication . Schmiing, Mara; Afonso, PedroMoulting, growth and retention of externally attached acoustic tags were studied in ten Mediterranean slipper lobsters, Scyllarides latus (Latreille, 1802). Animals were kept in a cage at 20 m depth in Faial Island, Azores, over a period of nine months. No negative effects of tag attachment on moult or behaviour were detected, but a negative effect on growth cannot be excluded. Moulting was correlated with ambient water temperature and resulted in an increase of approximately 7% in mean size and 17% in mean weight. The results demonstrate that the use of externally attached acoustic transmitters in this species is adequate for medium-term movement studies but not for longer-term annual studies, due to the rate of molting.
- Additions to a bibliography of the fauna of São Tomé e Príncipe and the island of Annobon, Gulf of Guinea. AddendumPublication . Gascoigne, AngusMais 182 documentos sobre a fauna de três das quatro ilhas no Golfo de Guiné (Príncipe, São Tomé e Annobon) são apresentados.
- Additions to the Azorean lichen flora.Publication . Aptroot, André; Rodrigues, António F.Ongoing lichenological research in the Azores yielded records of 38 new species for the lichen flora of the Archipelago: Agonimia papillata (O. Eriksson) Diederich & Aptroot, Amandinea lecideina (Mayrh. & Poelt) Scheid. & Mayrh., Arthonia ilicinella Nyl., Arthonia muscigena Th. Fr., Arthonia stellaris Kremp., Bacidia canariensis Erichsen, Buellia dives (Th. Fr.) Th. Fr., Caloplaca canariensis (Follman & Poelt) Breuss, Cliostomum flavidulum Hafellner & Kalb, Collema crispum (Huds.) Weber ex Wigg., Dimelaena radiata (Tuck.) Hale & W. Culb., Lecania hutchinsiae (Nyl.) A.L. Sm., Lecanora cenisia Ach., Lecanora hagenii (Ach.) Ach., Lecanora leprosa Fée, Lecanora orosthea (Ach.) Ach., Lecanora pulicaris (Pers.) Ach., Lecanora strobilina (Spreng.) Kieffer, Leptogium teretiusculum (Flörke) Arnold, Ochrolechia androgyna (Hoffm.) Arnold, Opegrapha calcarea Sm., Opegrapha herbarum Mont., Opegrapha multipuncta Coppins & P. James, Opegrapha niveoatra (Borr.) J.R. Laundon, Opegrapha prosodea Ach., Opegrapha varia Pers., Parmelinopsis minarum (Vainio) Elix & Hale, Pertusaria amarescens Nyl., Pertusaria lactea (L.) Arnold, Phaeographis smithii (Leight.) de Lesd., Phlyctis argena (Spreng.) Flot., Placidium squamulosum (Ach.) Breuss, Pyrrhospora quernea (Dicks.) Körb., Pyxine subcinerea Stirt., Ramalina lusitanica H. Magn., Rinod, Thelidium pyrenophorum (Ach.) Mudd, Verrucaria hydrela Ach. and Waynea adscendens V.J. Rico. The species Agonimia papillata, Caloplaca canariensis, Lecanora leprosa, and Pyxine subcinerea do not occur in continental Europe. The first species is also reported here from La Palma (Canary Islands).
- Additions to the lichen flora found on Cryptomeria japonica D. Don, in the Azores.Publication . Rodrigues, António F.; Aptroot, André; Freitas, Maria do Carmo; Sousa, Eva; Rodrigues, Carla; Amaral, Ana Sofia; Vieira, Bruno; Soares, PaulaTwenty-nine lichens species were reported in samples from Azorean Cryptomeria japonica forests. One species, Ramalina peruviana Ach., is newly recorded for the Macaronesian Region. On Cryptomeria japonica, seven new lichen records were found for the Azores: Parmotrema bangii (Vain.) Hale, Pyrrospora quernea (Dickson) Körber, Pyxine subcinerea Stirt., Ramalina implectens Nyl., Ramalina peruviana Ach., Usnea dasaea Stirton and Usnea esperantiana P. Clerc.The species Ramalina peruviana Ach., is rare within the Macaronesian Region.
- Age and growth of the alfonsino Beryx decadactylus (Cuvier, 1829) from the Azores, Madeira and Canary Islands, based on historical dataPublication . Krug, Helena; Carvalho, Dalila; González, José A.Age and growth of the alfonsino Beryx decadactylus from the Azores, Madeira and Canary Islands were studied based on otolith readings. Alfonsino otoliths are thin and show clear annual growth rings. Specimens ranged in size from 21.0 to 50.0 cm fork length (aged 2 to 10 years) in the Azores, 20.0 to 45.0 cm fork length (1 to 11 years) in Madeira, and 21.0 to 44.0 cm fork length (0 to 9 years) in the Canary Islands. No significant differences in growth parameters were found between males and females in any of the three archipelagos. [...].
- Age and growth of the Atlantic chub mackerel Scomber colias Gmelin, 1789 off Madeira IslandPublication . Vasconcelos, Joana; Dias, Manuel A.; Faria, GraçaThe Atlantic chub mackerel, Scomber colias Gmelin, 1789, is one of the main fisheries resources of Madeira Island. It is caught by a small and coastal purse-seine fleet that traditionally operates around the island. From January 2002 to December 2003, monthly samples of chub mackerel were collected from landings by this commercial fishing fleet. A total of 2212 sagitta otoliths were extracted for age readings from 1068 males (17.4-41.7 cm total length, TL), 1066 females (18.0-41.2 cm TL) and 78 undetermined (13.0-26.8 cm TL). A single reader aged the fishes using surface-read whole otoliths aiming to build annual age-length keys. Age readings precision and reader consistency were assessed by using the average percentage error index (APE ≤ 1.52). Ages were validated up to 4 years using marginal analyses. Estimated mean lengths at age and length von Bertalanffy growth curve parameters, estimated by non-linear methods, showed no significant differences (p>0.05) between sexes (L∞=50.08 cm TL, k=0.252 yr-1 and t0=-1.339 yr; males and females combined). Length-weight relationships were estimated aiming to convert growth in length to growth in weight. No differences between sexes were found in length-weight parameters (P>0.05). For sexes combined, total weight (TW, g) = 0.00218.LT 3.40 and the estimated asymptotic weight, W∞=1523.7 g.
- Age and growth of the blue jack mackerel, Trachurus picturatus Bowdich, 1825 (Pisces: Teleostei) off Madeira archipelago.Publication . Vasconcelos, Joana; Alves, Adriana; Gouveia, Elisabete; Faria, GraçaBetween 1984 and 1986, 630 pairs of sagitta otoliths were collected to determine the age and growth of the blue jack mackerel, Trachurus picturatus from Madeiran waters. The oldest specimen in this study was nine years old and the largest was 46 cm of total length (TL). The parameters of the von Bertalanffy growth curve were estimated for the whole period studied for all fish (L∞=42.32 cm, k=0.161 year-1, t0= -2.563 year; r2=0.743) for males (L∞=39.57 cm, k=0.194 year-1, t0=-2.282 year; r2=0.722) and for females (L∞=49.78 cm, k=0.114 year-1, t0=-3.052 year; r2 = 0.747). There was no significant differences in mean lengths (t–test, p>0,05) and in the von Bertalanffy growth curves (Ftest, p>0,05) between sexes. The validity of otolith readings for estimating age and growth was supported by results from backcalculation method. No significant differences were found in the Bertalanffy growth curves between direct reading of otoliths and backcalculation. Growth parameters estimated from backcalculated sizes-at-age were: for both sexes, L∞=48.28 cm, k=0.135 year-1, t0=-2.898 year and r2=0.999; for males, L∞=44.79 cm, k=0.143 year-1, t0=-3.207 year, r2=0.999; and females, L∞=44.63 cm, k=0.163 year-1, t0=-2.430 year, r2=0.999. The relationship between length and weight was calculated for all fish (Wt=0.00764Lt3.05746; r2=0.951), for males (Wt=0.01271Lt2.90807; r2=0.915) and for females (Wt=0.00604Lt3.12613; r2=0.948).
- Age and growth of the pink dentex Dentex gibbosus (Rafinesque, 1810) caught off the Madeira ArchipelagoPublication . Alves, Adriana; Vasconcelos, JoanaA total of 146 otoliths were extracted for age readings from 68 females (23.2-90.1 cm TL), 76 males (22.0-81.3 cm TL) and 2 undetermined (30.3-38.0 cm TL), between April 2004 and December 2007. The maximum age obtained from whole otoliths was 11 years. Differences in the growth rhythms were observed between the sexes (females: L∞=134.4, K=0.092 and t0=−0.406; males: L∞=135.9, K=0.078 and t0=−0.894; and all fish were: L∞=149.8, K=0.078 and t0=−0.784). Pink dentex attain 50% of their maximum theoretical length during their fourth year of life. The weight-length relationship (W = q Lfb) were determined separately for each sex and for all fish: for females q=0.01094 and b=3.033, for males q=0.10002 and b=3.047 and for all, q=0.01027 and b=3.046. According to the F-test, there were no significant differences between the weight-length relations obtained for females and males (F-test, F=2.2526, p=0.06646).
- Age and growth of the red porgy, Pagrus pagrus (Linnaeus, 1758) (Pisces: Sparidae), in Azorean watersPublication . Serafim, Maria Paula P.; Krug, HelenaAs espécies demersais dos Açores têm sido objecto de diversos estudos desde 1982 com vista à avaliação deste recurso. Este trabalho consistiu no estudo do crescimento de uma destas espécies, o Pagrus pagrus, através da observação dos otólitos e pela análise de frequências de comprimento. Para a estimação dos parâmetros da curva de crescimento de von Bertalanffy, em comprimento, foram utilizados três métodos, dois directos e um indirecto. A contagem dos anéis dos otólitos efectuou-se por dois processos diferentes: observação dos otólitos inteiros e observação de secções transversais finas. Os resultados de ambos os procedimentos foram coincidentes entre si. Os dois métodos directos usados para estimação dos parâmetros de crescimento a partir das estruturas duras (otólitos): cálculo directo e rectrócalculo, deram resultados semelhantes, Lt=103.0(1-e0.061(t+1.7)), e Lt=104.6(1-e-0.066(t+0.7)), respectivamente. A curva de crescimento, Lt = 102.7(1- e0.067(t+1.0)), semelhante às anteriores, foi obtida pelo método de estimação indirecta dos parâmetros de crescimento pela análise das frequências de comprimento através do programa MULTIFAN. Em todas as funções obtidas, o valor de crescimento assimptótico foi muito elevado quando comparado com o comprimento máximo observado (Lmax obs = 71 cm), e com outros estudos semelhantes. Este facto poderá ter resultado de uma amostragem incompleta nas classes etárias mais velhas. Pelos resultados obtidos pode-se afirmar que esta espécie apresenta um crescimento mais lento, e um ciclo de vida mais curto, comparativamente ao verificado no costa leste da América do Norte.