Category Archives: Field work

Door #18: A photosynthetic animal

You may already be confused with the title, but you did read it well! Animals can do photosynthesis and most incredibly some species are more efficient than plants or algae. Yet, this achievement is not for all; you must be special, you must be unique…, you must be a sapsucking slug!

Ercolania sp. feeding inside algae (Photo: M. Malaquias)

This is a process named kleptoplasty (= chloroplast symbiosis; see Door #2 of this calendar series) where the slug while feeding from the plant tissue does not digest the chloroplasts but instead migrate these organelles to specific parts of the body where they remain active producing sugars that become available to the slug.

There are two species of sapsucking slugs with a remarkable life-history. The spectacular and rare tropical species Ercolania endophytophaga and E. kencolesi both only known from Australia do not retain chloroplasts as other species do, but they do feed on algae, however, only on a very special kind – the green grape-algae of the Order Siphonocladales. These are syncytial algae made of massive single cell grape-shaped structures which the animal pierce to move in and leave inside until “green-matter” is available.

detail of Ercolania sp. inside algae (Photo: M. Malaquias)

I was very fortunate to find one of this slugs back in January 2014 in southern Mozambique. Usually one has to collect a large quantity of algae to carefully search through later on in the lab and hope for the best! However, in that afternoon while sampling in a beautiful shallow tidal tropical reef in Paindane sluggishly looking at a facies of a “grape-alga” growing over a boulder I suddenly notice a tiny animal moving gently inside the algae. I grabbed a few bunches of algae into my sampling jar to look at later on…, and voilà… I was rewarded with a few specimens of one of this spectacular and difficult slugs most probably an undescribed species, the first from the Indian Ocean.

Ercolania sp. after removal from algae (Photo: M. Malaquias)

-Manuel

Door #14: A world of colour and slime

Welcome to the world of Nudibranchs!

Flabellina rubrolineata (Mozambique) Photo: M. Malaquias

The nudibranchs are among the most beautiful animals in our seas. The palette of colours, shapes, and adaptations depicted by this group of gastropod molluscs has no parallel. Some species have no more than few millimetres where others can reach nearly half a meter. Some have a smooth skin, others are covered with long and delicate appendices.

Chromodoris boucheti (Mozambique) Photo: M. Malaquias

Phillidia ocellata (Mozambique) Photo: M. Malaquias

Most are benthic, but some are pelagic drifting with the oceanic currents. Nudibranchs feed on sponges, bryozoans, crustaceans, and cnidarians and even can incorporate in their tissues nematocysts sequestered from their prey which they use in self-defence. Probably, the most striking feature of these gastropods is the lack of a shell and presence of bright colours. These colours are usually a warning signal indicating the presence of deterrent chemicals some of them with pH values as low as 1 or 2. Some of these chemicals are biologically active and have been investigated for the treatment of several types of cancer diseases.

Flabellina pedata (Norway) Photo: M. Malaquias

Polycera quadrilineata (Norway) Photo: M. Malaquias

-Manuel

Door #12: Plankton sampling with a vertebrate view!

HYPNO participating on an Arctic cruise by the Institute of Marine Research on RV Helmer Hanssen 17 Aug – 7 Sep 2015.

Most of the pelagic hydrozoans for HYPNO are collected with simple plankton nets, in the case of this Arctic cruise the double one you see in the picture. The net is towed vertically from above the bottom to the surface, bringing with it a representative sample of plankton – inclusive hydromedusae and siphonophores – from the entire water column. Standard plankton nets are generally lowered and retrieved at a speed of ~0.5 ms^-1.

This particular station in the Arctic basin was over 2000 m deep, which means that a single tow takes more than an hour to complete. Sometimes waiting for the sample to come up can get a bit tedious – not at this station, though! With this beauty turning up right outside the hangar opening, the wait didn’t feel long at all!

-Aino

Door #11: Just a white blob?

Colobocephalus costellatus repainted from M. Sars (T.R. Oskars)

When researching small, obscure sea slugs you are bound to run into surprises. Partly because it often takes a long time between discovery and identification, and also because a lot of the really interesting stuff is first revealed when new methods become widely available.

In 2011 a team of researchers from the Invertebrates collection were sampling specimens in Aurlandsfjorden for the Invertebrate collections and range data for the Norwegian Biodiversity Information Centre (Artsdatabanken). Among other interesting critters they found a 2 mm long white blob. While not initially impressive this small blob turned out to be the enigmatic cephalaspidean sea slug Colobocephalus costellatus (Cephalaspidea: Heterobranchia) described by Michael Sars from Drøbak in 1870. At the time of its re-discovery it was thought that this species, which is unique for Norway, had not been seen or collected since M. Sars first laid hands on it 145 years ago (more (in Norwegian) here). However, you continuously discover more information in the course of scientific work. During their work on the enigmatic slug Lena Ohnheiser and Manuel Malaquias found in the literature that the species had in fact been discovered a couple of times since 1870, first by Georg Ossian Sars in Haugesund some years after his father, and more recently by Tore Høisæter of Bio UIB in Korsfjorden outside Bergen.

Still, no in-depth analyses have been done on this species since M. Sars until Nils Hjalmar Odhner of the Swedish Natural History Museum drew the animal from the side showing some of the organs of the mantle cavity.

Most authors have had real difficulties to place this slug within the cephalaspids, and M. Sars even thought is possible that the slug might not be an opisthobranch. Some placed it within Diaphanidae based only on the globular shell, a family that has been poorly defined and often used as a “dump taxon” for species that hare hard to place. Yet others thought it might even be the same as the equally enigmatic Colpodaspis pusilla, which has been suggested to be a philinid sea slug (flat slugs digging around in mud and sand).

What was unique about the most recent find was that this was the first time it was collected alive and photographed with high magnification. The material was also so fresh that Lena and Manuel could dissect the animal and study its internal organs. In their 2014 paper “The family Diaphanidae (Gastropoda: Heterobranchia: Cephalaspidea) in Europe, with a redescription of the enigmatic species Colobocephalus costellatus M. Sars, 1870” they tried to resolve the relationships between these globe shelled slugs. What they found was that Diaphanidae was likely not a real grouping of species, containing at least three distinct groups, where one group was Colobocephalus and Colpodaspis, which were closely related to each other, but also quite distinct.

Colobocephalus costellatus M. Sars, 1870. Photo: Lena Ohnheiser, CC-BY-SA. Also featured on http://www.artsdatabanken.no/File/1292

Another new development with the sampling in Aurlandsfjorden was that the slugs were preserved in alcohol rather than formalin. Formalin is good for preserving the morphology of animals, but it destroys DNA. On the other hand, alcohol is perfect for preserving DNA. This lead to C. costellatus to be included in a 2015 DNA based phylogenetic analysis of cephalaspidean sea slugs.

Modified Tree from Oskars et al. (2015)

This resulted in that the slug was found to be indeed an Opisthobranchia, and as Lena and Manuel thought, Colobocephalus and Colpodaspis were placed in their own family, Colpodaspididae. Whereas the traditional “Diaphanidae” was split apart. Even weirder was the sea slugs that were shown to be the closest relatives of Colpodaspididae, which were neither the philinids or the diaphanids. The closest relatives turned out to be slugs that are equally as weird and unique as Colpodaspididae, namely the swimming and brightly colored Gastropteridae (sometimes called Flapping dingbats) and the Philinoglossidae, which are tiny wormlike slugs that live in between sand grains.

*Cousin Meeting*
– “You sure we are related?”
– “Well, the scientists seem to think so. I see no reason to waste a good party!”

So it took 145 years from its discovery before Colobocephalus became properly studied and its family ties revealed, but it is still mysterious as we do not know much about their ecology or diet.

Suggested reading:

Colobocephalus costellatus: http://www.biodiversity.no/Pages/149747

Colpodaspis pusilla: http://www.biodiversity.no/Pages/149766

Philinoglossa helgolandica: http://www.biodiversity.no/Pages/149915

Høisæter, T. (2009). Distribution of marine, benthic, shell bearing gastropods along the Norwegian coast. Fauna norvegica, 28.

Gosliner, T. M. (1989). Revision of the Gastropteridae (Opisthobranchia: Cephalaspidea) with descriptions of a new genus and six new species. The Veliger, 32(4), 333-381.

Odhner, N.H. (1939) Opisthobranchiate Mollusca from the western and northern coasts of Norway. Kongelige Norske Videnskabers Selskabs Skrifter, 1939, 1–92.

Ohnheiser, L. T., & Malaquias, M. A. E. (2014). The family Diaphanidae (Gastropoda: Heterobranchia: Cephalaspidea) in Europe, with a redescription of the enigmatic species Colobocephalus costellatus M. Sars, 1870. Zootaxa, 3774(6), 501-522.

Oskars, T. R., Bouchet, P., & Malaquias, M. A. E. (2015). A new phylogeny of the Cephalaspidea (Gastropoda: Heterobranchia) based on expanded taxon sampling and gene markers. Molecular phylogenetics and evolution, 89, 130-150.

Sars, M. (1870) Bidrag til Kundskab om Christianiafjordens fauna. II. Nyt Magazin for Naturvidenkaberne, 172–225.

-Trond

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 #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 #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 #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?

: Our ride – R/V Hans Brattstøm – coming to pick us up in the morning

: A odd, bright light in the sky was observed

: The RP-sledge, used for collecting epibenthic fauna

: Decanting the RP-sample

: A plucky Pagurus prideux

: Hunting for animals

: Picking, picking

: Snapshot of a sample

: Hippasteria phryngiana

: Threathening clouds…time to head back!

Katrine and Anne Helene

Make sure to check back tomorrow to see what is behind Door #2…!

Greeting from the Faunistics course!

Today’s cutest catch – he’s a Rossia cephalopod

I’ve spent both last week and the current one at the UiB field station – Espegrend – together with an enthusiastic bunch of marine biology master students and their teachers.

Espegrend

I am mainly here to collect animals for NorBOL, but it’s hard to resist the temptation to join in on the course itself every now and again – whether in the field or in the lab!

Lots and lots of litterature

The baseline for the course is that the students will get to look at all sorts of freshly collected animals from various habitats and learn to identify them.

Kelp tank

Identified samples – at the end of each day, the students present the animals that they have studied that day to their classmates.

Whilst doing so, they acquaint themselves with the different keys and terminology used to identify the critters, learn which species are associated with which habitats, and get practical experience of how to collect and treat samples of various kind (you would for example use a different kind of gear to collect on a muddy substrate than on a rocky slope).

So it is a busy couple of weeks, with lots to learn.

Work on deck

Sponge-ID

First day in the field, Henrik is demonstrating

Incoming sample!

Tomorrow is the final day of collecting (it will be “parasite day”, which means a trawl to collect fish and various other animals likely to have parasites on (or in!) them.

Today we have focused on sponges, yesterday it was zooplankton, Monday was polychaetes – and so it goes!

Here are some of the animals that we have been working on:

: Aplysia punctata, sea hare

: Close-up of a Munida

: Acesta excavata, a fancy bivalve

: Leptasterias mulleri

: Flabellina gracilis

: A parasitic isopod in the genus Aega

: Limaria hians

: A snail in the family Naticidae, we’re not sure of the species yet.

The weather last week was…interesting, as was the absolute downpour a student and I went out in Monday morning – but today was simply a beautiful day for field work!

Stormy weather! Thankfully it passed after the first week. The map is from the really cool page earth.nullschool.net

Much, much nicer weather

As well as (re)presenting the Museum (yes, we do other things than the exhibitions, and ye-ees, we are interested in new students!), I gave a presentation of NorBOL and the work we are doing on marine animals last week (so far it is only animals, we will start with the marine macro algae the coming spring). I have been collecting quite a few new species that are to be barcoded from what the students work on, as well as supplementing what we have. In addition I will bring back some nice (but so far unidentified) samples to the Museum that we will continue to work on.

And who knows – maybe I have recruited some future collaborators?