Distribución vertical y horizontal de larvas de Monodaeus couchii frente a la costa sur de Portugal

A strong understanding of larval distribution and abundance is of major value in delineating the location and size of a breeding population of deep-sea species such as Monodaeus couchii. In this study, vertical distribution of the larvae of a brachyuran crab, M. couchii, was assessed during two week-long cruises conducted at the end of January 2006 and 2007 off the South Coast of Portugal. Larvae were collected by oblique plankton hauls with a Longhurst-Hardy Plankton Recorder from the surface to 300 m. Abundance and distribution of zoeae I and II were correlated during both years. For all stages, abundance decreased with depth during the day while it increased with depth at night; the larvae thus displayed reverse diel vertical migration. Abundance of zoeae I and II was correlated with chlorophyll a levels, whereas those of later stages were correlated with neither physical parameters (chlorophyll a, temperature or salinity) nor each other. An ontogenic shift in vertical distribution explained the results; earlier zoeal stages remain in the food-rich upper water column while later stages were not correlated with any physical parameters (i.e. chlorophyll a, salinity or temperature) and migrated to the bottom for settlement.El conocimiento de la distribución y abundancia larval es de vital importancia para comprender la localización y tamaño de la población reproductora adulta en especies abisales como Monodaeus couchii. En este estudio, la distribución vertical de las larvas de un cangrejo braquiuro, M. couchii, se evaluó durante dos campañas de una semana de duración al final de enero de 2006 y 2007, frente a la costa sur de Portugal. Las larvas se recogieron por pescas oblicuas de plancton con un “Longhurst-Hardy Plankton Recorder” (LHPR) desde la superficie hasta 300 m de profundidad. La abundancia y distribución de las zoeas I y II fueron correlacionadas para cada uno de los años de estudio. Para todos los estadios larvares la abundancia disminuyó con la profundidad durante el día, mientras que se incrementó con la profundidad durante la noche, mostrando por tanto un patrón de migración vertical inverso. La abundancia de zoeae I y II se correlacionó con los niveles de clorofila a, mientras que la abundancia de estadios posteriores no mostró correlación alguna con los parámetros físicos (clorofila a, temperatura o salinidad), ni entre sí. Estos resultados indican un cambio ontogénico en la distribución vertical de las larvas; los primeros estadios de zoea permanecen en la zona superficial de la columna de agua rica en alimento, mientras que las ultimas etapas que no mostraron correlación con los parámetros físicos (i.e. clorofila a, salinidad o temperatura) migran a zonas más profundas para el recrutamento

Description of the complete larval development of Lysmata amboinensis (De Man) (Decapoda: Lysmatidae) reared under laboratory conditions

This work was done under the framework of the project PLANTROF (MAR-01.04.02-FEAMP-0001) co-financed by MAR2020, Portugal2020 and European Union. MARE-Polytechnic of Leiria was supported by the Integrated Programme of SR&TD “Smart Valorization of Endogenous Marine Biological Resources Under a Changing Climate”, Portugal (Centro-01-0145-FEDER-000018), co-funded by Centro 2020 programme, Portugal 2020, Portugal, European Union through the European Regional Development Fund. The authors wish to express their sincere thanks to Ricardo Calado for his corrections and suggestions that clearly improve the manuscript.Complete larval morphological descriptions are currently only known for three of the 48 species of genus Lysmata. The present study describes and illustrates the larval development of Lysmata amboinensis (De Man) reared under laboratory conditions. Lysmata amboinensis larval development is composed by a total of ten zoea and a decapodite stage. The first zoeal stage larvae presents sessile eyes, a carapace with a pterigostomial spine and anterio-ventral marginal denticles, a long, slender, and pointed rostrum, an antennal exopod terminally segmented, a pleon with five somites, the fifth one bearing a pair of dorso-lateral spines on the posterior margin, and a triangular shaped telson with 7+7 posterior processes. The decapodite resembles a smaller adult and has extremely long antennas (more than twice the total length of the decapodite), the first two pair of pereiopods with chela, first four pairs of pereiopods with reduced and unsegmented exopods, and fully developed pleopods. The morphological features of L. amboinensis are compared with those currently available for the larval stage of the genus Lysmata.info:eu-repo/semantics/acceptedVersio

Lipkea ruspoliana Vogt, 1886 (Cnidaria: Staurozoa) in Portugal: the contribution of citizen science to range extension and taxonomic discussion of rare species

Citizen science online platforms are increasingly making important sources of biological information available at the click of a button, allowing the interaction of volunteers and scientists to report and identify the world's diversity. In this work, we combined the data available in citizen science platforms (iNaturalist and GelAvista) and the effort and collaboration of a diverse team of scuba-divers, scientists, and underwater photographers to report for the first time the presence of the stauromedusa Lipkea (Cnidaria: Staurozoa) in Portugal. Based on DNA (COI and 16S), we identified the species as Lipkearuspoliana. However, the marginal lappets of some Portuguese specimens are similar to those of Lipkeasturdzii, a species described based on a single specimen in 1893 and never reported again. These results suggest that L.sturdzii is a synonym of L.ruspoliana, although further taxon and habitat sampling for genetic studies and investigations of intraspecific morphological variation are necessary. In addition, we provided data on species ecology, reviewed the records of Staurozoa from Portugal, and mapped the world geographic distribution of Lipkea. Staurozoa is a cryptic group of cnidarians, and Lipkea seems to be a particularly rare genus. Citizen science has proved to be a valuable contribution to studies on the group, enabling biological discussions that otherwise would be more challenging.BIOMARES20212023; UID/MAR/04292/2018/2019; BiodivAMP Grant FA_06_2017_045; BiodivRestore ERA-NET Cofund (GA N°101003777); POCI-01-0247-FEDER-033889info:eu-repo/semantics/publishedVersio

Decapod crustacean larval community structure of the submarine canyon off Blanes (NW Mediterranean Sea)

Decapod crustacean fisheries play a crucial role on the northwestern Mediterranean coast due to their high commercial value. Although knowledge of larval ecology and recruitment dynamics of these species is essential to establish a sustainable fisheries management, they are still poorly known. In this paper, we describe the composition, abundance and distribution of decapod crustacean larvae in the submarine canyon off Blanes (northwestern Mediterranean Sea) during summer thermal stratification conditions. Samples were collected in September 2011 with a multi-net system and a 60-cm bongo net at 22 stations with bottom depths of between 100 and 1800 m. A total of 635 larvae from 60 genera were identified. The most relevant taxa were Aristeus antennatus (7.93 individuals/1000 m3), the family Sergestidae (7.24) and Alpheus glaber (6.78). These three taxa were dominant (>20% of total decapod larvae) at more than half of the stations. Decapod larval communities were found to be richer and more diverse at the canyon head, a finding which could be explained by the higher retention rates when compared with the upstream and downstream walls and the canyon axis.Las pesquerías de crustáceos decápodos juegan un papel crucial en la costa del Mediterráneo noroccidental debido a su alto valor comercial. Aunque la información sobre la ecología larvaria y las dinámicas de reclutamiento de estas especies es esencial para establecer una gestión sostenible de estas pesquerías, estos aspectos son aún poco conocidos. En este estudio, se describe la composición, abundancia y distribución de las larvas de crustáceos decápodos en el cañón submarino de Blanes (Mediterráneo noroccidental) durante las condiciones de estratificación térmica estival. Las muestras fueron tomadas en septiembre de 2011 con un sistema multi-red y una red bongo de 60 cm de diámetro en 22 estaciones con fondos de entre 100 y 1800 m de profundidad. Un total de 635 larvas de 60 géneros fueron identificadas. Los taxones más relevantes fueron Aristeus antennatus (7.93 individuos/1000 m3), la familia Sergestidae (7.24) y Alpheus glaber (6.78). Estos tres taxones fueron dominantes (>20% del total de larvas de decápodos) en más de la mitad de las estaciones. Se encontró que las comunidades larvarias de decápodos son más ricas y diversas en la cabecera del cañón, lo cual podría explicarse por los altos índices de retención que presenta esta zona en comparación con las paredes del cañón y su eje.info:eu-repo/semantics/publishedVersio

Estructura de la comunidad larvaria de crustáceos decápodos del cañón submarino de Blanes (Mediterráneo noroccidental)

Decapod crustacean fisheries play a crucial role on the northwestern Mediterranean coast due to their high commercial value. Although knowledge of larval ecology and recruitment dynamics of these species is essential to establish a sustainable fisheries management, they are still poorly known. In this paper, we describe the composition, abundance and distribution of decapod crustacean larvae in the submarine canyon off Blanes (northwestern Mediterranean Sea) during summer thermal stratification conditions. Samples were collected in September 2011 with a multi-net system and a 60-cm bongo net at 22 stations with bottom depths of between 100 and 1800 m. A total of 635 larvae from 60 genera were identified. The most relevant taxa were Aristeus antennatus (7.93 individuals/1000 m3), the family Sergestidae (7.24) and Alpheus glaber (6.78). These three taxa were dominant ( > 20% of total decapod larvae) at more than half of the stations. Decapod larval communities were found to be richer and more diverse at the canyon head, a finding which could be explained by the higher retention rates when compared with the upstream and downstream walls and the canyon axis.Las pesquerías de crustáceos decápodos juegan un papel crucial en la costa del Mediterráneo noroccidental debido a su alto valor comercial. Aunque la información sobre la ecología larvaria y las dinámicas de reclutamiento de estas especies es esencial para establecer una gestión sostenible de estas pesquerías, estos aspectos son aún poco conocidos. En este estudio, se describe la composición, abundancia y distribución de las larvas de crustáceos decápodos en el cañón submarino de Blanes (Mediterráneo noroccidental) durante las condiciones de estratificación térmica estival. Las muestras fueron tomadas en septiembre de 2011 con un sistema multi-red y una red bongo de 60 cm de diámetro en 22 estaciones con fondos de entre 100 y 1800 m de profundidad. Un total de 635 larvas de 60 géneros fueron identificadas. Los taxones más relevantes fueron Aristeus antennatus (7.93 individuos/1000 m3), la familia Sergestidae (7.24) y Alpheus glaber (6.78). Estos tres taxones fueron dominantes ( > 20% del total de larvas de decápodos) en más de la mitad de las estaciones. Se encontró que las comunidades larvarias de decápodos son más ricas y diversas en la cabecera del cañón, lo cual podría explicarse por los altos índices de retención que presenta esta zona en comparación con las paredes del cañón y su eje

First record of Palaemon macrodactylus Rathbun, 1902 (Decapoda, Palaemonidae) in the western Mediterranean

The Mediterranean Sea is one of the world’s hotspots for marine bio-invasions. Most invasions are first documented based on an initial record of occasional adult captures. However, reports of larval stages could indicate that there is an adult population that is reproducing and therefore well established in the area. The spread of the oriental shrimp, Palaemon macrodactylus, from its native estuarine waters of southeast Asia to new regions worldwide is well documented. We report the first record of this species in the Mediterranean based on the presence of its larval stages in plankton samples. Decapod larvae were collected in five offshore plankton surveys performed off the Balearic Islands (western Mediterranean), and zoeae III and VI of the oriental shrimp were found among them. Taking into account the duration of the successive developmental stages, and the hydrodynamic characteristics of the study area, these larvae were most probably spawned by adult populations not yet documented. The larvae were found in marine waters despite the fact that adults usually inhabit brackish waters. Our study is a good example of how plankton studies can help to detect larval stages of invasive species before the adult populations are detectedPublicado

Complete larval development of the crab Ilia nucleus (Linnaeus, 1758) (Decapoda, Brachyura, Leucosiidae) reared under laboratory conditions

The complete larval development of the crab Ilia nucleus (Linnaeus, 1758) reared under laboratory conditions was obtained. The four zoeal stages and the megalopa are described and illustrated in detail. The larval features observed in I. nucleus fit into the characteristics of the family proposed by Rice (1980) for the zoeal stages and by Quintana (1986) for the megalopa. The morphological characters of larval stages of I. nucleus are compared with previous descriptions, and with those of other known larvae of Leucosiidae (only for subfamilies Ebaliinae and Leucosiinae). The present work supports the hypothesis that the subfamily Ebaliinae is a heterogeneous group. For the correct identification of a zoeal stage of a leucosiid crab, besides counting the number of setae on maxilliped exopods, the antennule as well as the pereiopods development should be used as additional characters