Flora en fauna geassocieerd met mosselpopulaties in de Oosterschelde en Voordelta in 2009

In de periode van 5 tot en met 25 augustus 2009 zijn er bemonsteringen uitgevoerd van hangcultuur mosselen, mosselpercelen en MZI’s. In totaal zijn er 30 monsters genomen in de Voordelta en de Oosterschelde. In deze studie zijn 65 exoten geïdentificeerd die in potentie zouden kunnen worden geïntroduceerd met de zuid-noordtransporten van de mosselen. Tevens zijn er monsters genomen van MZIinstallaties, de hangcultures en bodemmosselen in de Oosterschelde en de Voordelta. Van de 116 aangetroffen soorten in de monsters uit de Oosterschelde waren 12 soorten gekenmerkt als exoot. In de MZI’s, die een relatief korte tijd in de Oosterschelde hangen zijn er in absoluut getal niet minder, maar wel andere soorten exoten aangetroffen dan in de bodemcultuur

A New Species of Hansenocaris (Crustacea : Facetotecta) from Tanabe Bay, Japan

A new species of "cypris y" (Crustacea: Facetotecta) is described from Tanabe Bay on the Pacific coast of Japan under the name Hansenocaris furcifera. The nauplius of this new species is "nauplius y type IX" sensu Ito. A possible penis is recognized in the Facetotecta for the first time, represented by an apically bifurcate process on the ventum of the first abdominal somite. External features of various body parts are described in detail based upon observations with a scanning electron microscope. New terms are proposed to describe certain structures

Metabarcoding successfully tracks temporal changes in eukaryotic communities in coastal sediments

Metabarcoding is a method that combines high-throughput DNA sequencing and DNA-based identification. Previously, this method has been successfully used to target spatial variation of eukaryote communities in marine sediments, however, the temporal changes in these communities remain understudied. Here, we follow the temporal changes of the eukaryote communities in Baltic Sea surface sediments collected from two coastal localities during three seasons of two consecutive years. Our study reveals that the structure of the sediment eukaryotic ecosystem was primarily driven by annual and seasonal changes in prevailing environmental conditions, whereas spatial variation was a less significant factor in explaining the variance in eukaryotic communities over time. Therefore, our data suggests that shifts in regional climate regime or large-scale changes in the environment are the overdriving factors in shaping the coastal eukaryotic sediment ecosystems rather than small-scale changes in local environmental conditions or heterogeneity in ecosystem structure. More studies targeting temporal changes are needed to further understand the long-term trends in ecosystem stability and response to climate change. Furthermore, this work contributes to the recent efforts in developing metabarcoding applications for environmental biomonitoring, proving a comprehensive option for traditional monitoring approaches.Peer reviewe

KEANEKARAGAMAN JENIS PAKAN PADA LAMBUNG IKAN SEPAT SIAM (Trichogaster pectoralis) DI RAWA BANJIRAN DESA SEDANG KECAMATAN SUAK TAPEH KABUPATEN BANYUASIN

The research on the diversity of feed types in the snakeskin gouramy hull was carried out in August to Desember in swamp flood, Sedang village, Suak Tapeh subdistrict, Banyuasin District. The method used is a field study with determination of stations carried out by purposive random sampling of 3 stations, namely the Nebong Kuning swamp station, the Poron swamp station and the Banan swamp station. This study aims to determine the diversity of feed types in the Sepat Siam fish hull in swamp flood, Sedang village, Suak Tapeh subdistrict, Banyuasin District. Based on the result of study found the type of feed in the sepat siam fish hull consisted of 2 groups, namely phytoplankton and zooplankton, which consisted of 5 classes namely Bacillariophyceae, Clorophyceae, Cyanophyceae, Crustaceae and Maxillopoda. Based on the diversity index of the type of snakeskin gouramy hull in Nebong Kuning Swamp station, the Poron swamp station and the Banan swamp station are included in the medium category which indicates that the habitat of the aquatic environment in which the snakeskin gouramy live namely swamp flood, Sedang village, Suak Tapeh subdistrict, Banyuasin District quite balanced and moderate ecological pressure. Keywords : Diversity, Feed, Flood Swamp, Hull, Snakeskin Gouram

Keanekaragaman Plankton di Perairan Desa Rigaih, Kecamatan Setia Bakti, Kabupaten Aceh Jaya

Plankton sangat berpengaruh terhadap keanekaragaman hidup biota karena memegang peranan sebagai komponen utama rantai makanan. Penelitian ini dilakukan untuk mengetahui keanekaragaman dan jenis-jenis plankton di perairan Desa Rigaih. Penelitian dimulai pada tanggal 10-03-2021 sampai dengan 10-04-2021. Penentuan stasiun menggunakan metode purposive sampling yang terdiri dari 4 (empat) stasiun pengamatan. Pengambilan sampel air menggunakan plankton net. Hasil penelitian menunjukkan bahwa keanekaragaman plankton terdapat perbedaan di setiap stasiun. Fitoplankton paling banyak ditemukan pada Kelas Bacillariophyceae sebanyak 11 jenis yaitu Hemiaulus sp., Chaetoceros sp., Coscinodiscrus sp., Detonula sp., Guinardia sp., Grammatophora sp. Leptocylindrus sp 1., Leptocylindrus sp 2., Rhizosolenia sp 1., Rhizosolenia sp 2., dan Stephanapyxis sp. Fitoplankton paling sedikit adalah Kelas Dynophyceae sebanyak 1 spesies yaitu Peridinium sp., dan Kelas Cyanophyceae sebanyak 3 spesies yaitu Certiium sp., Oscillatoria sp., dan Trichodesmium sp. Zooplankton terbanyak ditemukan pada Kelas Crustacea yaitu 2 spesies antara lain Nauplius sp dan Acartia sp. Kelas Cepepoda sebanyak 2 spesies yaitu Oithona sp., dan Calanus sp. Zooplankton paling sedkit adalah Kelas Maxillopoda sebanyak 1 spesies yaitu Cylopoid sp. Parameter kualitas perairan di Desa Rigaih memiliki suhu berkisar 25,1-280C, kecerahan 16,1 -18,2 m, pH 5,8 -7,8, oksigen terlarut 6,29- 9,23 Mg/L, dan salinitas berkisar 30,0 -32,0 ppt sehingga plankton dapat hidup dan berkembang secara baik

Systematic sequencing of mRNA from the Antarctic krill (Euphausia superba) and first tissue specific transcriptional signature

BACKGROUND: Little is known about the genome sequences of Euphausiacea (krill) although these crustaceans are abundant components of the pelagic ecosystems in all oceans and used for aquaculture and pharmaceutical industry. This study reports the results of an expressed sequence tag (EST) sequencing project from different tissues of Euphausia superba (the Antarctic krill). RESULTS: We have constructed and sequenced five cDNA libraries from different Antarctic krill tissues: head, abdomen, thoracopods and photophores. We have identified 1.770 high-quality ESTs which were assembled into 216 overlapping clusters and 801 singletons resulting in a total of 1.017 non-redundant sequences. Quantitative RT-PCR analysis was performed to quantify and validate the expression levels of ten genes presenting different EST countings in krill tissues. In addition, bioinformatic screening of the non-redundant E. superba sequences identified 69 microsatellite containing ESTs. Clusters, consensuses and related similarity and gene ontology searches were organized in a dedicated E. superba database http://krill.cribi.unipd.it. CONCLUSION: We defined the first tissue transcriptional signatures of E. superba based on functional categorization among the examined tissues. The analyses of annotated transcripts showed a higher similarity with genes from insects with respect to Malacostraca possibly as an effect of the limited number of Malacostraca sequences in the public databases. Our catalogue provides for the first time a genomic tool to investigate the biology of the Antarctic krill

Struktur Komunitas Perifiton pada Makroalga Ulva Lactuca di Perairan Pantai Ulee Lheue, Banda Aceh

The research about community structure of periphyton on macroalgae Ulva lactuca has been done in coastal waters Ulee Lheue, Banda Aceh. The purpose of this research was to know the periphyton community structure consisting of abundance, diversity index, evenness index, and dominance index, and calculate the area covered macroalgae Ulva lactuca. The research has been started from February until March 2016. The results showed that perifiton on macroalgae Ulva lactuca consists of classes Bacillariophyceae (13 species), class Chrysophyceae (1 species), class Cyanophyceae (3 species), class Dinophyceae (1 species), class Gastropoda (1 species), class Malacostraca (4 species), class Maxillopoda (2 species), class Pyramimonadophyceae (1 species), and class Ophiuroidea (1 species). Abundance of perifiton is 51.390-139.220 ind/cm2 where each observation site has a cover of macroalgae Ulva lactuca were classified as very good category. Bacillariophyceae class dominated in every site with coverage 56.809 ind/cm2. Perifiton diversity index ranged from 1,87 to 2,36 were classified category, evenness index ranged from 0,70 to 0,86 relatively high category, while the dominance index ranged from 0,12 to 0,23 relatively low category. Based on the values obtained, the community structure of periphyton on macroalgae Ulva lactuca in coastal waters Ulee Lheue ecological pressure indicates a moderately low level of dominance and the community was in stable condition.  Telah dilakukan penelitian mengenai struktur komunitas perifiton pada makroalga Ulva lactuca di perairan pantai Ulee Lheue, Banda Aceh. Penelitian ini bertujuan untuk mengetahui struktur komunitas perifiton yang terdiri dari kelimpahan, indeks keanekaragaman, indeks keseragaman, dan indeks dominansi, serta menghitung luas tutupan makroalga Ulva lactuca. Penelitian ini dilakukan pada bulan Februari-Maret 2016. Hasil penelitian menunjukan bahwa perifiton pada makroalga Ulva lactuca terdiri dari kelas Bacillariophyceae (13 spesies), kelas Chrysophyceae (1 spesies), kelas Cyanophyceae (3 spesies), kelas Dinophyceae (1 spesies), kelas Gastropoda (1 spesies), kelas Malacostraca (4 spesies), kelas Maxillopoda (1 spesies), kelas Pyramimonadophyceae (1 spesies), dan kelas Ophiuroidea (1 spesies). Kelimpahan perifiton yaitu 51.390-139.220 ind/cm2, dimana setiap titik pengamatan memiliki tutupan makroalga Ulva lactuca yang tergolong kategori sangat baik. Kelas Bacillariophyceae mendominasi di setiap titik pengamatan dengan jumlah rata-rata 56.809 ind/cm2. Indeks keanekaragaman perifiton berkisar 1,87-2,36 tergolong kategori sedang, indeks keseragaman berkisar 0,70-0,86 tergolong kategori tinggi, sedangkan indeks dominansi berkisar 0,12-0,23 tergolong kategori rendah. Berdasarkan nilai yang diperoleh, struktur komunitas perifiton pada makroalga Ulva lactuca di perairan pantai Ulee Lheue menunjukan tekanan ekologi yang sedang dengan tingkat dominansi rendah dan komunitas berada dalam kondisi stabi

Widespread Wolbachia infection in terrestrial isopods and other crustaceans

Wolbachia bacteria are obligate intracellular alpha-Proteobacteria of arthropods and nematodes. Although widespread among isopod crustaceans, they have seldom been found in non-isopod crustacean species. Here, we report Wolbachia infection in fourteen new crustacean species. Our results extend the range of Wolbachia infections in terrestrial isopods and amphipods (class Malacostraca). We report the occurrence of two different Wolbachia strains in two host species (a terrestrial isopod and an amphipod). Moreover, the discovery of Wolbachia in the goose barnacle Lepas anatifera (subclass Thecostraca) establishes Wolbachia infection in class Maxillopoda. The new bacterial strains are closely related to B-supergroup Wolbachia strains previously reported from crustacean hosts. Our results suggest that Wolbachia infection may be much more widespread in crustaceans than previously thought. The presence of related Wolbachia strains in highly divergent crustacean hosts suggests that Wolbachia endosymbionts can naturally adapt to a wide range of crustacean hosts. Given the ability of isopod Wolbachia strains to induce feminization of genetic males or cytoplasmic incompatibility, we speculate that manipulation of crustacean-borne Wolbachia bacteria might represent potential tools for controlling crustacean species of commercial interest and crustacean or insect disease vectors.This research was funded by a European Research Council Starting Grant (FP7/2007-2013 grant 260729 EndoSexDet) to RC and a Comité Mixte de Coopération Universitaire Franco-Tunisien grant to DB and FCC