Author Archives: katrine

Door #10: Old Stoneface

Today’s critter is a Lithodes maja, or Northern stone crab (Trollkrabbe in Norwegian). They live in depths between 80-500 meters, where they feed on algae, bottom dwelling animals, and of scavenging. They are much smaller than their relatives the King crab (Paralithdodes camtschaticus), reaching up to 150 mm across the carapace.

Despite the name, they are not true crabs – Brachyura, but rather Anomurans: “As decapods (meaning ten-legged), anomurans have ten pereiopods (legs), but the last pair of these is reduced in size, and often hidden inside the gill chamber (under the carapace) to be used for cleaning the gills. Since this arrangement is very rare in true crabs (for example, the small family Hexapodidae), a “crab” with only eight visible pereiopods is generally an anomuran.” (Wikipedia)

Hello, there! Shake hands? Photo: H. Hektoen

Martin encountered this one when participating on this year’s final MAREANO survey in the Barents Sea. MAREANO has been working on mapping the depth and topography, sediment composition, contaminants, biotopes and habitats through a combination of video stations and physical sampling of sediments and animals in Norwegian waters since 2006.

A cruise typically lasts between 10 and 20 days, and for most years MAREANO has had 2-3 cruises. The amount of stations and collected material is staggering!

The pile of samples halfway through the cruise Photo: M. Hektoen

A bucket of beam trawl collected material – sponges and Munida (squat lobsters) are dominant, together with our friend from the picture above. Photo: M. Hektoen

Below is a map over the “full stations”, the stations that also include physical samples of biological material from grab, sled and trawl. These samples are split into fractions, some to be further processed by MAREANO, whilst others are bulk fixated without further analysis. The MAREANO-identified animals and unsorted fractions from these stations are deposited at the University Museum once MAREANO is done with them. We then continue to process them; decide which samples are significant, sort the unsorted fractions, implement material into the museum collections, and make it available for further research. For the interactive maps, go here.

Screenshot from mareano.no showing the bottom stations per year.

-Martin & Katrine

Door #9: Delving into the DNA

From the pre-PCR lab

The four PCR-machines lined up

We are very fortunate in that we have a modern DNA lab available «just down the street» from us, as the University Museum is part of the shared Biodiversity laboratories (BDL) structure.

The BDL is a formalized cooperation between three research groups at Dept. of Biology (Marine biodiversity, Geomicrobiology and the EECRG), and two of the research groups at the University Museum. One of the senior engineers if this lab is a Museum employee, and from time to time we are also able to hire in other collaborators for specific projects.

Pipetting samples onto one of the plates that we fill with DNA-extracts

For the past couple of months we’ve had a technician – Morten – working on resolving some of the challenges that we run into when we work on COI barcoding of marine invertebrates.

Unlike many of the other groups that this method works exceedingly well for (like the Diptera), we are experiencing difficulties in obtaining DNA barcodes from a significant proportion of our samples.

We are currently focussing particularly on the Polychaeta (bristle worms), as this is the group we have submitted the majority of samples from in both our major barcoding projects: MIWA (Marine Invertebrates of Western Africa) and NorBOL (Norwegian Barcode of Life).

Morten has been working on obtaining DNA from the more problematic species, by troubleshooting and tinkering on various aspects of the ways we extract and amplify genes.

Basically there are more or less standardized ways of obtaining DNA, and these methods normally works well. Unfortunately (for various reasons) this is not always the case, and this is where we have to alter the protocols to see if we can find a way to retrieve the sample DNA from the specimens.

So far it looks quite promising; we’ve been able to fill in some of the most important “blanks” in our datasets – and we’re not done yet!

– Morten & Katrine

Door #8: One jar –> many, many vials

Sorting the Crustacean samples from our

Marine Invertebrates of Western Africa Project (MIWA)

Most work is more fun when working together. It also makes for better science to cooperate – and the easiest way to cooperate on taxonomy is to sit at the same lab for some time – to be able to look at the same specimens and see the same details that should be examined. This is the plan for the amphipods from the MIWA-project. Ania Jażdżewska from the University of Łódź in Poland is visiting our lab for an extended week of collaboration with me in a mini-workshop on the amphipod samples.

But before a visitor can come, preparations are necessary. So for the last 6 weeks I have been sorting all the ethanol-samples of our west-african crustaceans into separate orders (isopods, tanaidaceans, cumaceans, decapoda), and the amphipods (also an order) have been sorted to family.

: Ground zero: a jar of unsorted sample.

: Biodiversity in a dish! (photo: K. Kongshavn)

: Zooming in… there are many, many animals in this particular sample! (photo: K. Kongshavn)

: Spot the amphipods? (photo: K. Kongshavn)

: The samples are first sorted into the main groups (usually Crustacea, Polychaeta, Mollusca, Echinodermata and the multi-purpose category “Varia”) (photo: K. Kongshavn)

: The jars marked Crustacea are then turned over to the people who work on the various crustacean groups (Photo:A.H. Tandberg)

: From subphylum (Crustacea) to families and beyond (Photo:A.H. Tandberg)

: They then sort it further… (Photo:A.H. Tandberg)

: Here are the groups Anne Helene uses when sorting (Photo:A.H. Tandberg)

: Eventually we have a pile of vials sorted to family (or order, or species…) level (Photo:A.H. Tandberg)

98 samples have been split into 629 smaller vials – ready to be further examined when Ania comes.

We promise a follow-up on what this brings of fun science!

-Anne Helene

Door #7: Shrimp and salad

Hippolyte varians Leach, 1814 in sea lettuce, Ulva lactuca

This small shrimp can be found on the shore in small ponds at low tide. The species was recorded from Western Norway already in the early 19 hundreds by research curators in Bergens Museum (Appellöf, 1906; Grieg, 1927). Interestingly, as also observed by Appellöf (1906:page 124) individuals of this the species appear in many contrasting colour variants due to the ability of the the body to mimic the colours in the environment. The Norwegian name of Hippolyte varians is «sjøgressreke», which refers to its association with sea grass meadows (Zostera marina), in which a green body colour would seem to be an appropriate camouflage appearance. The specimen on this picture was caught in the littoral at the island Turøy amongst sea lettuce, Ulva lactuca. We see that there is a good colour match between the shrimp and the lettuce.

However, reddish, pink, brownish, black or even white colours have been are observed in other environments and it seems that at night time the shrimp may take a rest from the camouflage by attaining a transparent whitish blue appearance as shown by Moen’s picture here.

Knowledge about the distribution and biology of Hippolyte varians is summarised by C. d’Udekem d’Acoz.

References

Appellöf, A. 1906. Die Dekapoden Crustaceen. Meeresfauna von Bergen 2(3): 113-238.

Grieg, J.A. 1927. Decapoda Crustacea from the west coast of Norway and the North Atlantic. Bergens Museums Aarbok 7:1-53.

Udekem d’Acoz, C. (1996). The genus Hippolyte Leach, 1814 (Crustacea: Decapoda: Caridea: Hippolytidae) in the east Atlantic Ocean and the Mediterranean Sea, with a checklist of all species in the genus. Zoologische Verhandelingen (Leiden) 303: 1-133.

-Endre

Door #6: Associated Amphipods

Amphipods are a group of small crustaceans where most of the species we know are benthic (bottom dwelling) and marine. But within the benthic habitat there are many niches, and one of the more intriguing is the many ways of living on or inside another benthic animal. A few species become parasitic (feeding on their host), but for the most species living like this, it does not look like eating the host is the main objective. In these cases we term the amphipods as “associated with a host”.

To document some of these associations, I have had a wonderful cooperation with an amazing underwater photographer this year. Lill Haugen has photographed amphipods associated with hydroids, and sampled the amphipods afterwards for us. Documenting this kind of association is almost impossible without the help of divers – if we are lucky enough to sample a hydroid with our normal sampling gear, the amphipods fall off. It is not easy spotting these small animals for a diver either, but Lill says that it becomes easier with practice.

An amphipod family at home. Photo by Lill Haugen, all rights reserved

This photo is from the Oslofjord, at 25 m depth. With the photos from Lill we are able to say that this particular amphipod (from the family Stenothoidae) looks like it keeps the hydroid as a family home. The parents sit on the “stem” of the hydroid, and their children sit on the tentacles of the “flower”. This might be both to provide extra protection and food for the amphipod-children. The adult amphipods are 5mm long, their children 3mm.

Earlier studies have shown that amphipods of the family Stenothoidae often associate with molluscs – we have found several different species living inside bivalves (shells). Other amphipods might associate with other crustaceans such as crabs, or with sponges, anemones or snails (gastropoda).

For most amphipod species we know nothing about their life-history and possible associations. But the more we examine them, the more we learn..

Door #5: A (so far) undescribed species of bristle worm

Diopatra sp. Photo: M. Hektoen

Pictured above is a cute polychaete (bristle worm) from the genus Diopatra. It was collected in Mauritania, and has been photographed using Scanning Electon Microscopy (SEM). Although I ended up describing 9 new species of Diopatra worms in my master’s thesis, many worms were still left undescribed, this is one of those.

-Martin

Door #4: A cushioned star

This gorgeous sea star was first described by O.F. Müller in 1776. He gave it a species name fitting the characteristic appearance of the animal (Lat. Pulvillus= pillow, cushion). The common names in both English – Red Cushion Star- and Norwegian – Sypute – also reflect on this. Though most commonly red like the specimen pictured below, they can also be yellow-white. The white protrusions on the upper side the are gills. It lives at 10-300 meters depth, where it is often seen feeding on the coral Alcyonium digitatum. This particular specimen was collected during the course in marine faunistics this fall, in a locality just outside our field station close to Bergen.

Strangely enough, considering how common, conspicuous and wide-spread the species is, it has not been barcoded very frequently in BOLD – our specimen here will be the fifth in total to be submitted..!

Screen shot from a search in BOLD for the species

Screen shot from a search in BOLD for Porania pulvillus

-Katrine

Door #3: Prepare to be HYPNOtized

One of this year’s new projects at the Invertebrate collections is HYPNO – Hydrozoan pelagic diversity in Norway, funded by the Norwegian Taxonomy Initiative.

A selection of photos depicting some of the species encountered so far in the project

Hydrozoa are a class of cnidarians, the pelagic representatives of which include hydromedusae as well as colonial siphonophores and porpitids. They are thus “cousins” to the more familiar larger scyphozoan jellyfish such as the moon jelly or the lion’s mane jelly. The size of pelagic hydrozoans ranges from small medusae of less than 1 mm to siphonophore colonies reaching several meters in length. They are mostly predators that use their tentacles and stinging cells to catch other zooplankton or even fish larvae. Most of the time they go largely unnoticed by the public, but at times they can form blooms and deplete zooplankton as well as cause problems for aquaculture and fisheries or sting bathers.

The aim of HYPNO is to chart, document and DNA-barcode the diversity of hydromedusae and siphonophores occurring in Norway. Gelatinous zooplankton, including hydrozoans, has been generally less studied than their crustacean counterparts, and we know less about their diversity. This is due to several challenges in studying them. First of all, many pelagic hydrozoans, particularly the colonial siphonophores, are very fragile and often damaged during sampling with standard plankton nets. This can make it difficult to identify them. Secondly, preserving hydromedusae and siphonophores for later work is problematic. For morphological studies, they are best preserved in formalin, since most other fixatives used for zooplankton -including ethanol- cause distortion and shrinkage of their gelatinous bodies, rendering the animals impossible to identify. Formalin fixation, however, hinders further genetic work.

To overcome these practical problems, HYPNO uses gentle collection methods to obtain specimens in good condition. Collected samples are immediately examined for hydrozoans, and the live animals are identified and documented with photos before they are fixed in ethanol for DNA barcoding of CO1 and 16S sequences.

So far, HYPNO has participated on two cruises by the Institute of Marine Research: to the North Sea and Skagerrak on RV Johan Hjort 24 Apr – 4 May 2015 and to the Arctic Ocean and Fram Strait on RV Helmer Hanssen 17 Aug – 7 Sep 2015. So far, 34 species have been photographed and sampled for DNA. Here is a selection of pictures depicting some of the species encountered during these surveys.

You can read more about HYPNO at http://data.artsdatabanken.no/Pages/168312.

-Aino

Door #2: The Leaf Sheep Sea Slug

Costasiella (Pruvot-Fol, 1951) or Leaf Sheep Sea Slugs recently gained a lot of attention online, due to many of the species resembling cute green cartoon sheep, but there is much more to them than just their cute appearances.

Regular sheep vs Leaf Sheep Sea Slugs (ill: T.R. Oskars)

Within Heterobranchia (sea slugs and land snails) they fall within the Saccoglossa, or sap sucking sea slugs, which feed by sucking out the cell contents of algae. Some of the species within this group simply digest the entire cell straight away, whereas some have the unique ability to retain some of the cellular components from the algae in a functional state within their body, a process called kleptoplasty (plastid stealing).

Costasiella is one of these plastid thieves, who retain the chloroplasts of the algae and can use them to fix carbon trough photosynthesis, an ability that is unique for saccoglossans amongst animals, leading to the often being referred to as “crawling leafs”. The plastids can aid the slug to survive for extended periods without food, and even if the slugs are thought to benefit from the products of the plastids, in dark conditions they also seems to work just as well as emergency rations, making even the main role of the plastids questionable. In addition precisely how these slugs can retain the functional chloroplasts in their body is still unknown; however the leading theory was for a long time that Costasiella also stole genes for managing the plastids from the cell nucleus of the algae (horizontal gene transfer). Such genes have however not yet been found in the genome of Costasiella, but has been found in its saccoglossan cousin Elysia chlorotica who can in addition pass these genes on to their offspring. The chloroplasts are however not inherited by the next generation of Costasiella or E. chlorotica, so the young have to go out and find their own before they can be true “crawling leafs”. In addition to being cute ambassadors of slimy slugs, Costasiella is also a little mystery.

Suggested reading:

Christa, G., Gould, S. B., Franken, J., Vleugels, M., Karmeinski, D., Händeler, K., … & Wägele, H. (2014). Functional kleptoplasty in a limapontioidean genus: phylogeny, food preferences and photosynthesis in Costasiella, with a focus on C. ocellifera (Gastropoda: Sacoglossa). Journal of Molluscan Studies, 80(5), 499-507.

Christa, G., de Vries, J., Jahns, P., & Gould, S. B. (2014). Switching off photosynthesis: the dark side of sacoglossan slugs. Communicative & integrative biology, 7(1), 20132493-3.

Schwartz, J. A., Curtis, N. E., & Pierce, S. K. (2014). FISH labeling reveals a horizontally transferred algal (Vaucheria litorea) nuclear gene on a sea slug (Elysia chlorotica) chromosome. The Biological Bulletin, 227(3), 300-312.

de Vries, J., Christa, G., & Gould, S. B. (2014). Plastid survival in the cytosol of animal cells. Trends in plant science, 19(6), 347-350.

de Vries, J., Rauch, C., Christa, G., & Gould, S. B. (2014). A sea slug’s guide to plastid symbiosis. Acta Societatis Botanicorum Poloniae, 83(4)

-Trond

Door #1: A day at sea

Welcome to our marine invertebrates December calendar! In Norway it is very common for children to have a Advent calendar of some sort to help shorten the wait towards Christmas.

We’ve decided to run with the idea here on the blog, giving you a tidbit about our work every day from December 1st to 24th.

We hope you’ll join us on our little venture – we can guarantee a varied selection of topics!

All the posts will be gathered under the Category 2015 December calendar

First out is a tale of sampling in the sleet…!

The scientific collections are the backbone of all the research performed at the University Museum – as it is at any museum. They hold treasures collected through the entire lifetime of a museum, and most times a collection was the reason for the establishment of a proper museum. The University Museum of Bergen is one of the oldest natural history collections in Norway, and we have grand collections.

But a collection needs to live – to be added to and to be used of – and this was the reason that bright and early Monday morning Katrine and Anne Helene were ready to go to sea. Our goal was to make a jumpstart at Anne Helenes new project about Amphipods (more about that in a later blog), and to take a grab (or two) of sandy seafloor to look for bristle worms (Polychaeta).

It is always a risk planning on a cruise in the very end of November, but this time the weather was on our side. Our plan – “go out and grab animals, sandy bottom is nice” – was cooked up in the spur of the moment when we got an offer for boat time late Friday afternoon (someone else had to change their plans in the last minute), and maybe that was why everything went so smoothly? Going out collecting benthic animals (those that live on the seafloor) is one of our favourite things, and so we didn’t need much prodding.

The grab and sledge performed beautifully, and now is the time for sorting and photographing live animals before adding them to the collection. Be sure to follow their story through later blogs – they will show up in the categories NorAmph and NorBOL, and maybe somewhere else as well?