Category Archives: Current projects

Door #23: How far away can a quill worm get?

Hyalinoecia tubicola from the North Sea (by K. Kongshavn).

Hyalinoecia tubicola from the North Sea (by K. Kongshavn).

Quill worms belong to the annelid family Onuphidae and are called like that because of their unique tubes. The tubes are secreted by their inhabitants and are very light and rigid, resembling a quill, the basal part of a bird’s feather used for writing. Quill worms are epibenthic creatures capable of crawling on the surface of the sea floor carrying their tubes along. Their anterior feet are modified, strengthened and enlarged, bearing thick and stout bristles. These anterior feet are used for locomotion.

Quill worms are widely distributed in the ocean inhabiting mostly slope depths down to 2000 m. Being large in body size (up to 10-20 cm long), they can be quite abundant in some areas. Meyer et al. (2016) reported Hyalinoecia artifex reaching up to 70 ind./m2 in the Baltimore Canyon at 400 m water depth. Another quill worm, H. tubicola, which is very common in Norwegian waters, reached up to 272 ind./m2 at 365 m offshore of Chesapeake Bay (Wigley & Emery 1967).

Quill worms are believed to be motile scavengers. Baited monster camera experiments performed at 2000 m deep site in Baja California demonstrated that Hyalinoecia worms can accumulate in hundreds of specimens five hours after the bait (rotten fish) has been deployed (Dayton & Hessler 1972). Myer et al. (2016) analyzed the stable isotope content in Hyalinoecia artifex tissues confirming its secondary consumer status. Their results supported earlier observations on the gut content of the same species by Gaston (1987) showing the presence of the remains of various benthic invertebrates.

Video 1. Quill worm Hyalinoecia tubicola moving inside its tube (by K. Kongshavn).

 

Video 2. Quill worm Hyalinoecia tubicola protruding from the tube opening. Three antennae and a pair of palps are seen on the head. The first two pairs of feet are enlarged and strengthened (by K. Kongshavn).

 


Dayton, P.K., Hessler, R.R., 1972. Role of biological disturbance in maintaining diversity in the deep sea. Deep-Sea Research 19: 199–208.

Meyer, K.S., Wagner, J.K.S., Ball, B., Turner, P.J., Young, C.M., Van Dover, C.L. 2016. Hyalinoecia artifex: Field notes on a charismatic and abundant epifaunal polychaete on the US Atlantic continental margin. Invertebrate Biology 135: 211–224. doi:10.1111/ivb.12132

Gaston, G.R. 1987. Benthic polychaeta of the Middle Atlantic Bight: feeding and distribution. Marine Ecology Progress Series 36: 251–262.

Wigley, R.L., Emery, K.O. 1967. Benthic animals, particularly Hyalinoecia (Annelida) and Ophiomusium (Echinodermata), in sea-bottom photographs from the continental slope. In: Deep-Sea Photography. Hersey JB, ed., pp. 235–250. John Hopkins Press, Baltimore.

-Nataliya

Door #19: Going back to the roots

Last year we had a calendar post about the Heart of the Museum – our type collections.

To recap, a species’ type is “…the objective standard of reference for the application of zoological names. When a new species or subspecies is described, the specimen(s) on which the author based his/her description become the type(s) (Article 72.1). In this way names are linked to type specimens, which can be referred to later if there is doubt over the interpretation of that name.

Consequently types are sometimes referred to as “onomatophores” which means name bearers.”

International Commission on Zoological Nomenclature (IZN)

The location – sampling site – from which the type specimen is described is known as the type locality.

Michael Sars (image from Wikimedia)

Michael Sars (image from Wikimedia)

As you have probably noticed, polychaetes (bristle worms) are a focus group in our lab, and several species have type localities close by.

The biologist and theologian Michael Sars (1805-1869) lived in the Bergen region for many years.  He was a prolific taxonomist, naming 277 species of marine taxa according to the World Register of Marine Species (WoRMS).

 

Consequently there are quite a few species that have their type locality within easy daytrip-distance by ship for us.

On the hunt with R/V "Hans Brattstrøm"

On the hunt with R/V “Hans Brattstrøm”

cover

One such locality is Glesvær, where Michael Sars described several new species in his work of 1835:  Beskrivelser og Iagttagelser over nogle mærkelige eller nye i Havet ved den Bergenske Kyst levende Dyr af Polypernes, Acalephernes, Radiaternes, Annelidernes og Molluskernes Classer* (“Descriptions and Observations of some strange or new animals found off the coast of Bergen, belonging to the Classes …”).

The polychaete Amphicteis gunneri (Ampharetidae) is one of these species. It was first described by Michael Sars as Amphitrite gunneri (the species name is an homage to Johan Ernst Gunnerus (1718-1773) who was an active scientist within botany and zoology,  as well as the bishop in Trondheim, and one of the founders of Det Kongelige Norske Videnskapers Selskap) in the publication above. Here are his original illustrations of the species:

gunneri

Amphicteis gunneri by M. Sars (1835)

We have previously submitted several specimens of Amphicteis gunneri for DNA-barcoding through the NorBOL-project – and found that specimens that according to the keys in the literature should all come out nicely as A. gunneri in fact end up in several barcode-based groupings (BINs), meaning that they genetically different from each other. Then we need to unravel which one is the true A. gunneri, and decide what to do with the others. In such cases, material from type localities is invaluable. By sending in specimens identified by resident taxonomists as A. gunneri from the type locality, we hope to figure out which BIN represent A. gunneri, and which represent potentially new species.

We were also able to photograph live specimens showing the nice coloration of this worm. Fixed specimens lose this colour and become uniformly yellow/white (no dots).

Amphicteis gunneri collected at type locality. Photo: K.Kongshavn

Amphicteis gunneri collected at type locality. Photo: K.Kongshavn

*Thanks to the excellent Biodiversity Heritage Library, this publication can be found in full text online, accessible for everyone – go here to see it. The Flickr stream of BHL is also an excellent source of amazing illustrations, you can find that here.

-Tom & Katrine

Door # 18: MSc completed

Congratulations to Jenni, our (former!) master student, who presented her MSc project last Friday!

She has been working on the phylogenetic systematics and evolution of a genus of small marine gastropods called Phanerophthalmus, and she’s done an impressive amount of work.

Phanerophthalmus crawling on seagrass. Photo: M. Malaquias

Phanerophthalmus crawling on seagrass. Photo: M. Malaquias

 

The project was titled
Systematics, biogeography, and trophic ecology of the genus
Phanerophthalmus A. Adams, 1850 (Mollusca, Cephalaspidea, Haminoeidae) in
the Indo-West Pacific, and was supervised by Manuel Malaquias.

Celebrating our freshly minted MSC with coffee, cakes and bubbles

Celebrating our freshly minted MSC (second from the left in top photo) with coffee, cake and bubbles!

We wish you all the best, Jenni!

Door #17: New master student

Polina

Polina

Polina Borisova, a first year master student from the Zoological Department of the Moscow State University (Russia), is coming to the Invertebrate Collections of the University Museum of Bergen with a 1-month research visit in January 2017.

Polina is going to work on the bristle worms from the family Lumbrineridae studying the collection from West Africa and Norway. Her project is jointly supervised by Dr. Nataliya Budaeva from the University Museum of Bergen and Dr. Alexander Tzetlin from the Moscow University.

Various Lumbrineridae from West Africa, scale 1 mm (Photos from BOLD).

Various Lumbrineridae from West Africa, scale 1 mm (Photos from BOLD).

Lumbrineridae are the worms with relatively poor external morphology but complex jaw apparatus. The structure of jaws has been traditionally used in the systematics of the family in the generic diagnoses. Polina is utilizing the methods of microCT to study the jaws of lumbrinerids in 3D.

Jaws of Scoletoma fragilis from the White Sea scanned using microCT showing ventral solid mandibles, forceps-like maxillae I and denticulate maxillae II and II, carriers of maxillae are omitted (Photo: P. Borisova)

Jaws of Scoletoma fragilis from the White Sea scanned using microCT showing ventral solid mandibles, forceps-like maxillae I and denticulate maxillae II and II, carriers of maxillae are omitted (Photo: P. Borisova)

Polina is also going to sequence several genetic markers to reconstruct the first molecular phylogeny of the family. This will allow testing the current hypothesis on the intergeneric relationships within Lumbrineridae and will aid in tracing the evolution of jaws within the family.

-Nataliya & Polina

Door #16: Chaetoderma nitidulum- a spiny, shiny mollusc

Molluscs come in a variety of shapes and sizes, but some of the least known are perhaps the Aplacophora, or shell-less molluscs. Instead of a shell, these worm-shaped molluscs have a cuticle covered in calcareous spicules, or sclerites, that give them a beautiful, glistening appearance!

The very first species of aplacophoran mollusc, Chaetoderma nitidulum, was collected from the Swedish west coast and described by the Swedish taxonomist Sven Lovén in 1844. At the time, it was not even known what animal group the new, strange animal belonged to. It had spicules– could it be related to the spiny sea urchins? It had a worm-like body– could it be related to other worm-shaped animals? It would be almost 50 years before it was conclusively recognized as part of Mollusca. Since then, many more species have been discovered, and today close to 500 species of aplacophoran molluscs have been described.

A specimen of Chaetoderma nitidulum from the Norwegian West Coast Photo: N. Mikkelsen

A specimen of Chaetoderma nitidulum from the Norwegian West Coast Photo: N. Mikkelsen

Chaetoderma nitidulum is known today as one of the common aplacophoran molluscs in the East Atlantic, with a distribution from the Svalbard archipelago in the north, to the British Isles in the south. However, taxonomist have been debating the identity of Chaetoderma nitidulum since shortly after it was described. Some researchers have suggested that it could in fact consist of up to six different species. Other researchers have synonymized it with other species, or suggested that it is not a separate species, but only part of a larger species which has a distribution that spans the entire North Atlantic.

The shape, size and the patterns on the calcareous sclerites covering the body of the aplacophoran molluscs is unique to each species, making it one of the most important characters we have to distinguish between different species.

Calcareous clerites from Chaetoderma nitidulum. Photo: N. Mikkelsen

Calcareous clerites from Chaetoderma nitidulum. Photo: N. Mikkelsen

Looking at the sclerites through the microscope equipped with a cross-polarizing filter gives us a shiny, colorful view of the sclerites. The light shines with different colors depending on the thickness of the sclerites, helping us get a good view of the structure of the sclerites.

Sclerites from Chaetoderma nitidulum viewed under cross-polarized light. Photo: N. Mikkelsen

Sclerites from Chaetoderma nitidulum viewed under cross-polarized light. Photo: N. Mikkelsen

We have recently investigated specimens of Chaetoderma nitidulum from different localities from the entire distribution range of the species. Our investigations have revealed a lot of variation between the specimens, both in the calcareous sclerites and in DNA sequences, separating the specimens into at least two different groups. Could it be that Chaetoderma nitidulum actually represents more than one species?

-Nina

Door #12: All aboard the jelly cruise!

Travelling alone through the water column may be a dangerous business: reaching the final destination is not always guaranteed, the risk of being eaten is high, and even finding food may prove a difficult task… which is why several animals choose to travel comfortably on or inside jellyfish and siphonophores!

Jellyfish are commonly involved in relationships of parasitism and phoresis (i. e., when one organism is mechanically transported by another without any further physiological dependence), and many examples have been observed of these interactions around the world. For instance, it’s not unusual to find hyperiid amphipods and sea-spiders –as well as lobster and crab larvae – piggybacking on the surface of large and tiny jellyfish, and while it’s still not clear whether or not all these passengers feed on their means of transportation, real parasitism and jelly-feeding has been confirmed for at least some of them. Jellyfish may also transport parasitic worms to their final hosts (like the nematode you see in the pictures), acting as carriers of parasites towards fish and mammals, and sometimes, eventually reaching humans as well!

Euphysa aurata medusa with parasitic nematode larva. Korsfjord, February 2016. Credit: Aino Hosia.

Euphysa aurata medusa with parasitic nematode larva. Korsfjord, February 2016. Credit: Aino Hosia.

A close-up of 2 showing the parasite embedded in the mesoglea (jelly) of the host. Credit: Aino Hosia.

A close-up of 2 showing the parasite embedded in the mesoglea (jelly) of the host. Credit: Aino Hosia.

Euphysa aurata medusa with crustacean ectosymbiont. Raunefjord, December 2016. Credit: Luis Martell

Euphysa aurata medusa with crustacean ectosymbiont. Raunefjord, December 2016. Credit: Luis Martell

These two hydromedusae of Euphysa aurata were collected this year in the fjords south of Bergen, and are only an example of jellyfish harboring other animals in this area. The species is a common and widespread jellyfish around here, but its role in the transmission of parasites and transportation of small crustaceans has never been explored. It might well be that, together with its gelatinous relatives, E. aurata will prove to be involved in many more biological interactions than we previously thought!

Luis Martell

Door #10: Siphonophores

Today, I thought I’d introduce to you to a cool group of animals that is ubiquitous in the oceans (including the Norwegian seas), but unfamiliar to most people. Siphonophores (“kolonimaneter” in Norwegian) belong to cnidarians, a group that includes corals, anemones, hydroids and jellyfish, and is characterized by the presence of stinging cells used in prey capture. All siphonophores are predatory, and use their stinging tentacles to catch small crustaceans or, in the case of some species, even small fish.

The most (or only) familiar siphonophore for the majority of people is probably the highly venomous Portuguese Man O’War (Physalia physalis), which can be spotted floating on the surface of the ocean or stranded on beaches. However, it is not really representative of the group as a whole, as most siphonophores live in the water column of the open ocean rather than its surface. There are around 200 described species of siphonophores.

The most fascinating feature of siphonophores is their peculiar body plan. While siphonophores may appear to be a single animal, they are in fact a colony of physiologically connected and genetically identical but morphologically diverse individuals called zooids that have specialized to carry out different tasks for the colony. Siphonophores belong to the class Hydrozoa (“polyppdyr” in Norwegian), which covers two basic body plans: the polyp/hydroid and the medusa.

Schematic of a physonect siphonophore. From http://www.siphonophores.org (CC-by-nc-sa)

Schematic of a physonect siphonophore. From http://www.siphonophores.org (CC-by-nc-sa)

The various zooids comprising a siphonophore colony can also be divided into these main groups. For example, the zooids used for swimming, called nectophores, are medusoid, while the feeding zooids, or gastrozooids, are polyp-like. The siphonophore colony can also include specialized defensive, protective and reproductive zooids. All the zooids forming a colony arise by budding from a single fertilized egg. The different zooids are specialized to the degree that they cannot function as individual animals any more, and are only able to perform their specific tasks as parts of the siphonophore colony.

Anterior nectophore, posterior nectophore and eudoxid of the calycophoran siphonophore Dimophyes arctica – a common species in Norwegian waters. Photos by Aino Hosia (cc-by-sa)

Anterior nectophore, posterior nectophore and eudoxid of the calycophoran siphonophore Dimophyes arctica – a common species in Norwegian waters. Photos by Aino Hosia (cc-by-sa)

The zooids, for example the swimming nectophores, vary in appearance between species, and can be used for species identification. In addition, the various types of zooids in the colony are arranged in a strict species specific pattern, providing the intact colonies of each species with their particular appearance. While the individual zooids are generally small, millimeters to centimeters in size, some siphonophore species, like Praya dubia, may have colonies that reach 40 m in length! Siphonophore colonies generally have a zone of one or more (up to several dozen) swimming nectophores at the front, used to pull the colony through water. Behind this nectosome is the siphosome, which contains the feeding, reproductive and other zooids in a repeating pattern, each iteration of which is called a cormidium. In some species (suborder Calycophorae), these cormidia are released as small free-living reproductive colonies called eudoxids. Unfortunately, siphonophore colonies are extremely fragile and tend to fall apart during standard plankton sampling with nets, leaving behind a bewildering array of small bits and pieces – part of the reason they are relatively poorly known to most people.

Colony of physonect siphonophore Physophora hydrostatica, aka hula skirt siphonophore. Photo by Aino Hosia (cc-by-sa)

Colony of physonect siphonophore Physophora hydrostatica, aka hula skirt siphonophore. Photo by Aino Hosia (cc-by-sa)

Intact siphonophore colonies are beautiful, but often utterly alien in appearance. It is interesting to consider where to draw the line between an individual and a colony. While we as individuals have specialized organs to carry out our various bodily functions, siphonophore colonies are made up of specialized interdependent individuals or zooids similarly carrying out their specific tasks.

As part of project HYPNO we are charting the diversity of pelagic hydrozoans, including siphonophores, in Norway. There are ~15 species observed in Norwegian waters, and some, particularly Dimophyes arctica, Lensia conoidea and Nanomia sp. are extremely common components of marine plankton. However, siphonophores are primarily noticed when they become a nuisance: For example, mass occurrences of Muggiaea atlantica and Apolemia uvaria have in the past killed large numbers of farmed fish in Norway, with resulting losses to aquaculture companies.

– Aino (HYPNO)

Intrigued by siphonophores? For more information, visit e.g. http://www.siphonophores.org/  by Casey Dunn.

Door #9: Research stay of Juan Moles

Juan working at the Museum

Juan working at the Museum

During my stay at the University Museum of Bergen I have been working on the diversity and systematics of Antarctic philine snails. Most of the samples were collected during different cruises on board of the RV Polarstern in the Eastern Weddell Sea, Bouvet Island, and South Shetland Islands (West Antarctica). I photographed all specimens and then clipped them for the DNA analysis (see pictures).

 

 

 

 

 

I was able to work at the DNA lab with excellent resources for DNA extraction, amplification, purification, and sequencing.

I am indebted to Louise Lindblom who helped me at the beginning of my crusade there. After a first barcoding of all the material we identified six clades, from which we selected a maximum of three specimens to further sequence the ribosomal genes 16S and 28S and the nuclear gene codifying for the Histone 3.

The first phylogenetic tree with all partitions resulted in the finding of novel clades that now deserve further investigation.

Prof. Manuel António E. Malaquias and his PhD Student Trond Oskars helped me dissecting the material for anatomical analyses. Important taxonomical characters were those related to the male reproductive system, the digestive tract as well, and the shell. After the dissections and drawings of the main parts I prepared the hard structures such as the radula, the shell, and the gizzard plates for Scanning Electron Microscopy (SEM) as well as some soft structures after critical point drying. I could photograph all these material at the same facilities of the museum being helped by Irene and Katrine. After the two months of work, I ended up having huge amount of anatomical and molecular data that deserves further processing. See a picture of the radula and a gizzard plate:

Moreover, I was able to join the student diving club and make several dives to get to know the local flora and fauna. I could even collect some other heterobranch slugs for the barcoding project of the museum. See a couple of pictures of the nudibranch Limacia clavigera and Onchidoris muricata.

Overall, Bergen is a nice city to visit surrounded by nice mountains, good (but not cheap) beers, beautiful fjords, and nice people. I hope I can come back with a postdoctoral position to further enjoy the country and meet more Viking descendants.

-Juan

Door # 6: Stuffed Syllid

Todays calendar critter is a Trypanosyllis sp. – a undescribed species from the genera Trypanosyllis in the family Syllidae. It most closely resembles a species described from the Mediterranean Sea. The Norwegian species is common in coral rubble, and has been assumed to be the same species as the one described from the Mediterranean. Genetic work reveals that these two are in fact separate species, and thus the Norwegian one is a new species awaiting formal description and naming. (If you read Norwegian, you can learn more about how species are described and named here: Slik gir vi navn til nye arter).

A new species of Trypanosyllis, collected in Sletvik, Norway. Photo by Arne Nygren. CC-by-sa

A new species of Trypanosyllis, collected in Sletvik, Norway. Photo by Arne Nygren. CC-by-sa

This specimen was collected, identified and photographed by Arne Nygren during our field work in Sletvik as part of his work on cryptic polychate species in Norway.

Syllids have opted for a rather fascinating way of ensuring high fertilization rates; something called epitoky: they asexually produce a special individual – the epitokous individual – from their bodies, and release this to go swimming in search of a mate. In the photo you can see that the female reproductive body (epitoke) is filled with orange eggs and has its own set of eyes, close to the middle of the animal. This section will break away from the mother animal and swim away in search of a male reproductive body to reproduce with. The mother animal will then grow a new female reproductive body.

-Arne & Katrine

Door #5: A visit from Mario

The collections have many guest researchers come here to work on our material, and one of our most frequent guests of lately has been Mario, who makes the long trip from Colombia to study both the West African material that we have from the MIWA-project, and to work on Nordic material. We asked him to make a contribution to the blog, and got the folllowing:

Mario in the Lab

Mario in the lab

For October – November visit.

For my third time in the Museum, I have found, as always, very good company from my colleagues in the lab: Katrine, Nataliya, Jon and Tom. Deep morphology and molecular method discussions over very good coffee were the “breaks” between periods of hard work at the microscope.

This time, I take to my home two papers close to completion; one about species of the genus Pista (Terebellidae) with additional information to what I found during my last visit in January. The second paper is about species in the subfamily Polycirrinae (Terebellide) from the West coast of Africa.

The idea is combine drawings, digital photos of specimens with methyl-green staining pattern and SEM pictures, as well as molecular information that will hopefully help us separate species and make better estimates of the region’s biodiversity.

Field work - somewhat cold and windy

Field work – somewhat cold and windy

 

The visit – which was without snow and with only a few showers of rain in Bergen (!), though with some very cold and windy moments at the Marine Station of the University of Trondheim – and sharing time with recognized polychaetologist as Fred Pleijel, Torkild Bakken, Eivind Oug, and Arne Nygren, was as spectacular as to know the Aurora Borealis.

Aurora borealis and a hooded tropical visitor. Photo: K.Kongshavn

Aurora borealis and a (hooded) tropical visitor. Photo: K.Kongshavn