The Arnold Berliner Award 2014

The Arnold Berliner Award (Thatje 2012) was established as part of the 100-year anniversary of Naturwissenschaften and was first awarded in 2013 (Fig. 1, Thatje 2013). With this editorial, it is my great pleasure to announce this year’s recipient of the award, Florian Karolyi from the University of Vienna

Larval stages of Chorismus tuberculatus (Decapoda: Caridea: Hippolytidae) from the south-western Atlantic Ocean

Larval development of Capitulum mitella (Cirripedia: Pedunculata) comprises six nauplius stages and a cyprid. Unilobed labrum, a larval trait of pedunculate and chthamalid barnacles, bears two groups of slender hairs and two pairs of strong teeth on the distal labral margin, and a pair of teeth on the lateral labral margin. Frontolateral horns extended under the anterior cephalic shield margin are diagnostic features through all nauplius stages. The posterior border of the cephalic shield bears a pair of distal cephalic shield spines in nauplius stages II and III, and a pair of long posterior shield spines in nauplius stages IV, V and VI. A hispid seta is consistently found at the fourth group of the antennal endopodite through stages II–VI. The dorsal thoracic spine, abdominal process and the paired posterior shield spines have numerous small spines. Morphological features such as the cephalic shield, labrum, abdominal process, antennules, antennae and mandibles in all nauplius and cyprid stages are illustrated and described. In this species, the numerical setations of the antennule are found to be beneficial for intra-specific identification of barnacle nauplius stages without the need for dissection.<br/

Comparison of heat-shock responses between the hydrothermal vent shrimp Rimicaris exoculata and the related coastal shrimp Palaemonetes varians

The deep-sea vent shrimp Rimicaris exoculata is believed to occur at the hot end of the hydrothermal biotope in order to provide essential elements to its epibiosis. Because it is found close to hot venting water, R. exoculata lives in a highly fluctuating environment where temperature (2–40 °C in the swarms) can exceed its critical maximal temperature (33–38.5 ± 2 °C). In order to understand how this vent shrimp copes with hyperthermia, we compared its molecular heat stress response following an acute but non-lethal heat-shock (1 h at 30 °C) with that of its monophyletic shallow-water relative, the shrimp Palaemonetes varians, known to frequently undergo prolonged exposure at temperatures up to 30 °C in its natural environment during summer. We isolated four isoforms of heat-shock proteins 70 (HSP70) in R. exoculata (2 constitutive and 2 inducible isoforms) and two isoforms in P. varians (1 constitutive and 1 inducible isoform) and quantitatively compared their magnitude of induction at mRNA level, using real-time PCR, in the case of experimentally heat-stressed shrimps, with respect to control (unstressed) animals. Here, we report the first quantification of the expression of multiple hsp70 genes following heat stress in a deep-sea vent species living at 2300 m depth. Our results show a strong increase of hsp70 inducible genes in the vent shrimp (not, vert, similar 400-fold) compared to the coastal shrimp (not, vert, similar 15-fold). We therefore propose that, the highly inducible molecular response observed in R. exoculata may contribute to the ability of this species to tolerate thermal extremes

Metabolic rate and growth in the temperate bivalve Mercenaria mercenaria at a biogeographic limit, from the English Channel

Metabolism and growth rate of the hard clam, Mercenaria mercenaria, were investigated in a population invasive to Southampton Water, southern England. An individual metabolic model expressed as a function of soft tissue dry mass was fitted to data of 18 individuals (log (VO2) = −1.952 + 0.543 • log (DM); F1,16 = 201.18, P &lt; 0.001, r2 = 0.926). A von Bertalanffy growth function was fitted to 227 size-at-age data pairs of 18 individuals (Ht = 80.13 • (1 − e−0.149 • (t−0.542)); r2 = 0.927). Individual age-specific somatic production was calculated, demonstrating increase with age to a maximum of 3.88 kJ y−1 at ten years old followed by decrease, and individual age-specific annual respiration was calculated, demonstrating asymptotic increase with age to 231.37 kJ y−1 at 30 years old. Results found here lie within the physiological tolerances reported across the biogeographical range, suggesting that the species' biogeographical limitation in the UK to Southampton Water results from ecological rather than physiological factors

Relación filogenética de los Cumacea (Crustacea: Peracarida) y variabilidad genética de dos especies antárticas de la familia Leuconidae

Phylogenetic hypotheses for the peracarid order Cumacea are scarce and have not provided a solution to the full extent. In the present study, a fragment of the mitochondrial 16S rDNA was used to erect a phylogenetic hypothesis for three cumacean families, Diastylidae, Bodotriidae and Leuconidae, along with intra-family relationships of the latter. The Cumacea resolved monophyletic with tanaids and isopods as outgroup taxa. The Diastylidae were the only family with good support for monophyly. The genus Leucon resolved paraphyletic, whereas the subgenus Crymoleucon was monophyletic. Furthermore, the genetic structure was analysed for two leuconid species, Leucon antarcticus Zimmer, 1907 and L. intermedius Mühlenhardt-Siegel, 1996, from the Weddell Sea and the Ross Sea. The two species showed different patterns of intraspecific genetic variability. In contrast to L. intermedius, a bimodal distribution of pairwise genetic distances was observed for L. antarcticus, which is correlated with geographical and depth distributions between the Ross Sea and the Weddell Sea. Although a clear evaluation of cryptic speciation in these species requires additional work on more specimens from more geographic regions and broader depth ranges, differences shown in the sequences of 16S rDNA can only be explained by genetic separation of populations between the Weddell Sea and the Ross Sea for an extended period of time.Las hipótesis filogenéticas para los peracáridos del orden Cumacea son escasas y no han proporcionado una solución definitiva. En el presente estudio se utilizó un fragmento del rDNA 16S mitocondrial para formular una hipótesis filogenética para tres familias de cumáceos, Diastylidae, Bodotriidae y Leuconidae. Además se han analizado las relaciones intrafamiliares de esta última. Los cumáceos es un grupo monofilético con tanaidáceos e isópodos como taxones externos. De las tres familias analizadas, los Diastylidae fueron la única con buen apoyo para la monofilia. El género Leucon se resolvió parafilético mientras que el subgénero Crymoleucon fue monofilético. Además, se analizó la estructura genética de dos especies de leucónidos Leucon antarcticus Zimmer, 1907 y L. intermedius Mühlenhardt-Siegel, 1996 del mar de Weddell y el mar de Ross respectivamente. Ambas especies mostraron diferentes patrones de variabilidad genética intraespecífica. A diferencia de L. intermedius, para L. antarcticus se observó una distribución bimodal del mismatch distribution, que se correlaciona con las distribuciones geográficas y de profundidad entre el mar de Ross y el mar de Weddell. Aunque una evaluación clara de la especiación críptica en estas especies requiere trabajo adicional con más especímenes de más regiones geográficas y rangos de profundidad más amplios, las diferencias que se muestran en las secuencias del rDNA 16S solo pueden explicarse por la separación genética de poblaciones entre el mar de Weddell y el mar de Ross durante un período de tiempo prolongad

Egg development, hatching rhythm and moult patterns in Paralomos spinosissima (Decapoda: Anomura: Paguroidea: Lithodidae) from South Georgia waters (Southern Ocean)

Larval release, hatching rhythms and moult patterns were examined in a captive population of the subantarctic lithodid, Paralomis spinosissima from the South Georgia and Shag Rocks region. Larvae hatched throughout the year with the majority of females starting to release larvae at the end of the austral summer and beginning of autumn. Larval release continued over a period of up to 9 weeks with high variability in the numbers that hatched each day. A similar seasonal pattern to hatching was evident in the moulting of females. Intermoult period for two adult females (CL = 63 and 85 mm) ranged from 894 to 1,120 days while an intermoult period for males was estimated to be in excess of 832 days. The results are consistent with other species of Paralomis and are discussed in relation to physiological and environmental adaptations to the cold-water conditions south of the Antarctic Convergence

Las centollas colonizan la Antartida

Es conocido que en Antartida no viven cangrejos. El hallazgo en los ultimo años de centolla podria estar anunciando la futura conquista de la Antartida por los cangrejos

The effect of high hydrostatic pressure acclimation on acute temperature tolerance and phospholipid fatty acid composition in the shallow-water shrimp Palaemon varians

Extant deep-sea fauna, including hydrothermal vent endemics such as bresiliid shrimp, are descended from shallow-water ancestors. Previous studies have demonstrated the capacity of shallow-water shrimp to acclimate to hydrostatic pressure representative of the vent environment. It has been proposed that this hyperbaric acclimation depends in part on shifts in phospholipid fatty acid composition to maintain biomembrane function. These shifts are also predicted to reduce critical temperature tolerance, potentially limiting the possibility of direct colonisation of the hydrothermal vent environment. Here, we present evidence that acclimation to high hydrostatic pressure (10MPa≈1000m water depth) decreases acute temperature tolerance from 30.2°C to 27.1°C in the shallow-water shrimp Palaemon varians acclimated to 10°C. Statistically significant shifts in phospholipid fatty acid composition occurred during exposure to high hydrostatic pressure, suggesting that homeoviscous modifications support shifts in environmental tolerances during hyperbaric acclimation. Despite the reduction in temperature tolerance, P.varians retains sufficient thermal scope to tolerate the thermal regime in the hydrothermal vent environment, allowing for the possibility of direct deep-sea hydrothermal vent colonisation by shallow-water shrimp

Adaptations to hydrothermal vent life in Kiwa tyleri, a new species of yeti crab from the East Scotia Ridge, Antarctica

Hydrothermal vents in the Southern Ocean are the physiologically most isolated chemosynthetic environments known. Here, we describe Kiwa tyleri sp. nov., the first species of yeti crab known from the Southern Ocean. Kiwa tyleri belongs to the family Kiwaidae and is the visually dominant macrofauna of two known vent sites situated on the northern and southern segments of the East Scotia Ridge (ESR). The species is known to depend on primary productivity by chemosynthetic bacteria and resides at the warm-eurythermal vent environment for most of its life; its short-range distribution away from vents (few metres) is physiologically constrained by the stable, cold waters of the surrounding Southern Ocean. Kiwa tylerihas been shown to present differential life history adaptations in response to this contrasting thermal environment. Morphological adaptations specific to life in warm-eurythermal waters, as found on – or in close proximity of – vent chimneys, are discussed in comparison with adaptations seen in the other two known members of the family (K. hirsuta, K. puravida), which show a preference for low temperature chemosynthetic environments