Category Archives: Crustacea

New year, new field work!

2019 will bring a lot of field work for us at the invertebrate collections – not only do we have our usual activity, but we will also have *FIVE* Norwegian Taxonomy Initiative projects (Artsprosjekt) running!

On a rather windy Tuesday in January, four of us – representing four of these projects – set out with R/V “Hans Brattstrøm”.

Four projects on the hunt for samples! Photo: A.H.S. Tandberg

Our main target for the day was actually not connected to any of the NTI-projects – we were hunting for the helmet jellyfish, Periphylla periphylla. We need fresh specimens that can be preserved in a nice way, so that they can be included in the upcoming new exhibits we are making for our freshly renovated museum. We were also collecting other “charismatic megafauna” that would be suitable for the new exhibits.

We have been getting Periphylla in most of our plankton samples since last summer, so when we decided this was a species we would like to show in our exhibits about the Norwegian Seas, we did not think it would be a big problem to get more.

This is a species that eats other plankton, so normally when we get it, we try to get rid of it as fast as possible; we want to keep the rest of the sample! But we should have known. Don’t ever say out loud you want a specific species – even something very common. Last November, we planned to look specifically for Periphylla, and we brought several extra people along just because of that. But not a single specimen came up in the samples – even when we tried where we “always” get them…

Lurefjorden is famous for being a hotspot for Periphylla – so the odds were in our favor! Map: K. Kongshavn

Wise from Novembers overconfident cruise, this time we planned to call to the lab IF we got anything to preserve. The Plankton-sample did not look too good for Periphylla: we only got a juvenile and some very small babies. So we cast the bottom-trawl out (the smallest and cutest trawl any of us have ever used!), and this sample brought us the jackpot! Several adult Periphylla, and a set of medium-sized ones as well! Back in out preparation-lab an entire size-range of the jelly is getting ready for our museum – be sure to look for it when you come visit us!

We of course wanted to maximize the output of our boat time– so in addition to Periphylla-hunting, we sampled for plankton (also to be used for the upcoming ForBio-course in zooplankton), tested the traps that NorAmph2 will be using to collect amphipods from the superfamily Lysianassoidea, checked the trawl catch carefully for nudibranchs (Sea Slugs of Southern Norway, SSSN) and benthic Hydrozoa (NorHydro), and used a triangular dredge to collect samples from shallow hard-bottom substrate that can be part of either SSSN or the upcoming projects NorHydro (“Norwegian marine benthic Hydrozoa”) or “Invertebrate fauna of marine rocky shallow-water habitats; species mapping and DNA barcoding” (Hardbunnsfauna).

The Hardbunnsfauna project was especially looking for Tunicates that we didn’t already have preserved in ethanol, as we want to start barcoding these once the project begins in earnest (last week of March). We also collected bryozoans, some small calcareous sponges, and (surprise, surprise!) polychaetes.

When it comes to hydrozoans, we were lucky to find several colonies of thecate hydroids from families Campanulariidae and Bougainvilliidae that represent some of the first records for NorHydro. Hydroid colonies growing on red and brown algae were particularly common and will provide a nice baseline against which diversity in other localities will be contrasted.

Different hydroid colonies growing on algae and rocks at the bottom of Lurefjorden. Photo: L. Martell

There were not a lot of sea slugs to be found on this day, but we did get a nice little Cuthona and a Onchidoris.

But what about the Amphipod-traps? Scavengers like Lysianassoidea need some time to realize that there is food around, and then they need to get to it. Our traps have one small opening in one end, but the nice smell of decomposing fish also comes out in the other end of the trap. We therefore normally leave traps out at least 24 hours (or even 48), and at this trip we only had the time to leave them for 7 hours. The collected result was therefore minimal – we even got most of the bait back up. However, knowing that we have a design we can deploy and retrieve from the vessel is very good, and we got to test how the technical details work. It was quite dark when we came to retrieve the traps, so we were very happy to see them! All in all not so bad!

We had a good day at sea, and it will be exciting to see some of our animals displayed in the new exhibits!


If you want to know more about our projects, we are all planning on blogging here as we progress. Additionally you can find more on the

-Anne Helene, Cessa, Luis & Katrine 

Door #20 The Hitchhikers Guide to the Ocean

The sea is for most of its inhabitants a vast place where danger can get to you anywhere. This might be especially true when you are one of those small and mostly harmless species spending your life slowly swimming around, minding your own business (eating and reproducing), somewhere in the upper 200m or so of water. Because there are many big-mouthed and possibly big eyed animals out there that think you might be one of the best things there is to eat.

Hyperiella antarctica with Spongiobranchaea australis. Photo: C Havermans, AWI.

For the small pelagic (living in the open ocean and not close to the sea floor) amphipods in the suborder Hyperiidea this is one of the dangers of everyday life. The genus Hyperiella can be found in the Southern Ocean, and one of their main predators are the icefishes (Nototheniidae). So what do you do when you are a small and quite tasty animal that is not a very fast swimmer and there are a lot of fishes out there to eat you?

Don´t panic!

Hyperiella antarctica with Spongiobranchaea australis (a and b) and Hyperiella dilatata with Clione limacina antarctica (c). Figure 2 Havermans et al 2018.

Two of the three Hyperiella-species have found a quite ingenious solution. They hitchhike with a group of other small slow-swimming pelagic animals – pteropods. Pteropods (from the greek “wing-foot”) are sea snails (gastropods). Hyperiella australis pics up a life with Spongiobranchaea australis, and Hyperiella dilatata hangs out with Clione limacina antarctica. Both pteropods are from the group we call Sea Angels (Gymnosomata), and in a way they are saving angels for the amphipods: the ice fish don´t eat these strange couples. Why?

It seems the pteropods have developed a chemical protection against predation. They obviously taste extremely bad, for observations of icefish trying to eat the hitchhiking amphipods together with the pteropods result in them both being spit out again. Most times, the fish would see what it thought was good food, and then swim away when they discovered what they were almost eating. Not so very strange, then, that Hyperiella are holding on to their colleagues for their life!

 

 

Clione limacina antarctica. Photo C Havermans, AWI.

It might not be hitchhiking after all, but rather kidnapping – or brute force. The amphipods hold on to the pteropods with their to-three hindmost pairs of legs, and keep the sea angel on their back – much like a backpack. Observations are that they are repositioning them there all the time – almost like kids running with bumpy backpacks on the way to school. They don´t even let go when the researchers preserve them!

Hyperiella antarctica with Spongiobranchaea australis backpack. Photo: C Havermans, AWI

What this treatment do to the pteropods we still don´t know. But it does not seem they are able to eat very much when being held hostage as chemical defence-backpacks. That may not be the biggest problem in a short time-scale – their Arctic relatives have been shown to survive almost a year without food. What happens when they really get hungry we do not know. The amphipods are still able to feed, even though the pteropods can be up to 50% of the amphipod size. Maybe the pteropods do some of the swimming for the amphipods?

This behaviour is much more common close to the coast than in the open sea: close to the McMurdo area, 75% of the Hyperiella were seen hitching with a pteropod. Now we know that this pairing can be found in the open sea, and maybe is it more common that we think. It is not the first thing we have looked for so far when examining samples. When the University Museum of Bergen joins the Norwegian Polar Institute and the Institute of Marine Research to the Southern Ocean in the austral autumn this coming March, we will make a special effort to search for such collaborators.

Anne Helene


Literature

Havermans C, Hagen W, Zeidler W, Held C, Auel H 2018. A survival pack for escaping predation in the open ocean: amphipod-pteropod associations in the Southern Ocean. Marine Biodiversity https://doi.org/10.1007/s12526-018-0916-3

McClintock JB, Janssen J 1990. Pteropod abduction as a chemical defence in a pelagic Antarctic amphipod. Nature 346:424-426.

 

 

Door #9: To catch an Amphipod

As many of you might have read earlier in this blog, the projects NorAmph and Hypno have been regularly sampling in Hjeltefjorden for the past year. As a part of my master thesis, I was lucky to be able to come with! My thesis will be about amphipods and their seasonal variety in Hjeltefjorden, which is super exiting!

The RP-sled used for the sampling.

For each time we go out, we sample with a RP-sled, a WP3 plankton net and we collect CTD data. The samples from the RP-sled will be used for my thesis and other projects if we find something interesting. During the last year we collected samples 9 times, which has given us some great days out at sea!

During these cruises we have had lots of fun! We have had cake, snacks and regularly done yoga on deck! We have been mostly lucky with the weather (except for our original cruise day in February, which had to be moved due to lots of wind, which you can read about here: Solskinnstokt)

 

A great view from our February cruise, with a clear blue sky and no wind! (Photo: K. Kongshavn)

We have been mostly lucky in getting great samples!

Lots of exciting material to get our hands on! (photo: AH Tandberg)

But sometimes not so lucky…

It is not easy to be a happy master student when the codend is almost empty… (Photo: AH Tandberg)

In October we had our last cruise, which was a great end to a year of sampling! We were not as lucky with the weather this time, but the samples look very nice. We also had cake to celebrate the last cruise day!

A great view in Hjeltefjorden (Photo: C. Østensvig)

Coffee breaks on deck are always important! (Photo: AH Tandberg)

It is somewhat sad to be done with the sampling, but with all the material collected, it is time to hit the lab! With all the samples, I sort out and identify all the amphipods I find. So far, I have found lots of cool amphipods, and I am starting to see some patterns in the material.

Here are some of the Amphipods I have found. All photos: K. Kongshavn

My work in the lab is far from done, and I am excited to look for new cool amphipods and hopefully find something interesting in their seasonal variation.

-Christine

Door # 8: The DNA-barcode identification machine

In a previous blog post I explained briefly how DNA-sequences are produced for the DNA-barcode library. Now I will show how the BOLD database can be utilized to identify species from sequences.

Some of the equipment used to produce DNA-sequences in our lab.

Say you have access to a lab that can produce DNA-sequences and you have a sample of a crab you cannot identify because some of the key characters are on body parts that have been broken and lost. You produce a DNA-sequence from the “barcode-gene” and open the identification engine in BOLDSYSTEMS.org.

Internet start window for the BOLD identification engine where you paste your unknown DNA sequence into the bottom blank window. (Click on picture to expand)

Having submitted your query to BOLD, you wait for some seconds for results. In this example BOLD returned the following window.

Example of results from a query to the BOLD identification engine. (Click on picture to expand)

The results window lists the top matches in terms of sequence similarity, and in this case we have 100 % similarity match with the crab Atelecyclus rotundatus. There is also an option to display the results as a TREE BASED IDENTIFICATION. When clicking on the option tab, the closest hits are clustered in a so-called Neighbour Joining Tree. In the window below you see parts of the tree where our unknown DNA-sequence has been joined to a group of other sequences in BOLD that have been deposited as Atelecyclus rotundatus barcodes by other biodiversity labs.

Part of TREE BASED IDENTIFICATION of an unknown DNA sequence (in red). We see that the unknown clusters with with other sequence of Atelecyclus rotundatus. The nearest neighbour branch is Atelecyclus undecimdentatus. (Click on picture to enlarge.)

The species page for Atelecyclus rotundatus gives us more information about this crab and about its records in BOLD.

Species page for the individual we identified with the BOLD identification engine. (Click picture to enlarge.)

If in fact your sequence was produced from an unknown crab, this identification seems convincing. But sometimes you should think twice about search results, and this will be the topic of a future blog post.

-Endre

Door # 6: The key to the question

We often say that without knowing the species you examine, you really can’t know a lot about whatever it is you are examining. But how do you get from knowing for example “this is an amphipod” to knowing “this is Amphilochoides serratipes”?

Three different Amphilochidae from Iceland

Most researchers would usually stop at the “this is an amphipod”-stage, and many specialists  would call it a day at “this amphipod belongs to the familily Amphilochidae”. but then there are the one or two researchers who have gone on to specialise in this family (I think there are three of us in the world at the moment).

But finally – those days are over!
As a special gift on this Nicholaus-day when all German colleagues get a special gift from St Nicholaus (who is Father Christmas) we present to all of you – regardless of nationality or faith:

The interactive and illustrated key to the NorthEast Atlantic species of Amphilochidae

The key is a product of a collaboration between the NorAmph-project and the German-lead IceAGE project that examines benthic animals around Iceland, and the technical production and web-hosting of the key is from the Norwegian Taxonomy Initiative (Artsprosjekt) (who – we have to say – also have financed the NorAmph-project!) Hurrah for a great collaboration!

Figure 14 from Tandberg et al

You might still wonder what an Amphilochid amphipod is?

The family Amphilochidae are amphipods that are quite small (1-6mm in length) and quite stout. They are not extremely good swimmers, though much of that can be from their small size – and from their short appendages. They can be found all over the world, and are common at many depths in our cold waters. Even though they are small and easily overlooked, they sometimes occur in relatively large numbers, and can contribute significantly to both the biomass and diversity of a sample. They have been found on hydrothermal vents at the southern part of the Mid-Atlantic ridge, and some have been found as loose associates of other invertebrates.

Also – they are quite cute, don’t you think?  Good luck with the identification!

-Anne Helene

Literature:

Brix S et. al. 2018. Amphipod family distributions around Iceland. ZooKeys 731: 1-53. doi: 10.3897/zookeys.731.19854

Tandberg AHS, Vader W 2018. On a new species of Amphilochus from deep and cold Atlantic waters, with a note on the genus Amphilochopsis (Amphipoda, Gammaridea; Amphilochidae). ZooKeys 731: 103-134. doi: 10.3897/zookeys.731.19899

Guest researcher: Marla

Marla, who has been visiting several times to work on our amphipod collections, sent us this “travelogue” from her longest stay. In her own words:

I am a third year PhD student, and my project is shared between the University of Southampton at the National Oceanography centre and the Natural History Museum in London. I am supervised by Dr Tammy Horton (NOC), Dr Andrew Gates (NOC), Dr Phil Fenberg (UoS), Dr Miranda Lowe (NHM), and Dr Andrea Waschenbach (NHM).

I spent 8 glorious weeks in Bergen working with the invertebrate collections at the Department of Natural History of the University Museum of Bergen (UiB) together with the wonderful Anne Helene Tandberg and Endre Willassen. Also a massive thank you to Katrine Kongshavn, Morten Stokkan, Jon Kongsrud, Luis Felipe Martell Hernández, Aino Hosia, Tom Alvestad, Nataliya Budaeva, Manuel Malaquias, Louise Lindbloom, and Kenneth Meland for your help in the lab and support with my project and lunchtime conversations!

I arrived to Bergen mid- September just in time for the 2017 UCI Road World Championships! As a huge fan (and very amateur road cyclist) this was such a bonus to have the chance to see it. The race took over the town, and one late afternoon Anne Helene and I climbed half-way up Mount Fløyen to watch the men’s Time Trial. The sun was out, the streets were packed, atmosphere was electric and we had prime seats–I couldn’t wait to see Chris Frome (GB) and Tom Dumoulin (NL) cycling in action.  It was a fantastic afternoon!

Anne Helene and I enjoying the afternoon UCI race from our prime viewing spot

The classic road graffiti to show support to the cyclists. Here Tom Dumoulin is forever immortalized on Mount Fløyen.

Tom Dumoulin won first place in the men’s Time Trial, Chris Froome took third.

Back in the lab…

I was working with amphipods from the family Phoxocephalidae from the Western African Waters, focussing particularly on the amphipods from the sub-family Harpiniinae [crustacea; Amphipoda; Phoxocephalidae; Harpiniinae]. Phoxocephalid amphipods are highly speciose and abundant in deep sea sediments globally. Species identity is critical to understanding mechanisms driving observed biodiversity patterns and to asses community change. The aim of the project while in Bergen was to use both DNA barcoding and traditional morphological taxonomic approaches in order to create a robust library of Phoxocephalidae species from the poorly known West African waters. Large scale projects such as Marine Invertebrates of West Africa (MIWA) provide the perfect opportunity for collaborative work! More about the MIWA-project can be found here.

The MIWA project submitted over 2700 tissue samples from over 600 morphospecies for DNA barcode sequencing, including Crustaceans, Echinoderms, Molluscs and Polychaetes. Out of these, 45 samples were from the family Phoxocephalidae, the target taxa. Working with Dr Anne Helene Tandberg and Prof Endre Willassen, the sequenced MIWA Phoxcephalid voucher specimens were dissected and mounted as permanent microscope slides to morphologically score them. Later, the phylogenetic analysis based on all molecular and morphological characters will be compared. Each appendage was photographed on the modular (Leica CTR6000) microscope and the images were stacked, resulting in incredible photos!

Harpinia abyssi P7. Photo: M. Spencer

As a result of some of this work, we think that we have identified 4 new species to the genus of Basuto. The genus was previously monotypic, with the type-locality in South Africa. Now we are awaiting the holotypes and paratypes to arrive so that we can compare. Together with Anne Helene, Endre Willassen and Tammy Horton, I am currently writing my first publication, formally describing these specimens as new species. Stay tuned for further updates!

Basuto specimen pereopod 5. Photo: M. Spencer

Basuto specimen Mandible, Photo: M. Spencer

At work in the DNA lab

Working with Anne Helene within the molecular biology labs at the University of Bergen, I had the chance to develop taxon specific primers and PCR conditions for the Harpiniinae MIWA specimens which were not successfully sequenced with the Universal primers. As a starting point, an additional 13 MIWA specimens had tissue extracted for DNA, and then dissected and permanent slides were made in order to morphologically score them. Each appendage was photographed and the images stacked. The primers and PCR conditions are a work in progress; however, this was a very successful trip resulting in a lot of data to analyse!

I also had the chance to explore the fantastic city of Bergen! I absolutely loved my time spent here- I generated a lot of data and learned so many new skills and new insight into my PhD project. Win-win! I look forward to returning again one day.

-Marla

The amphipods around Iceland – fresh special issue

IceAGE stations with amphipods. Red stations are analysed in the special issue. Fig 1 from Brix et al 2018

As the IceAGE-project presents their amphipod results in a special issue of ZooKeys, the invertebrate collections are represented with co-authors in 4 of the 6 papers. All papers in the special issue are of course Open Access.

Endre, Anne Helene and IceAGE-collaborators Anne-Nina and Amy have examined the Rhachotropis species (family Eusiroidea) from Norwegian and Icelandic waters, using material both from NorAmph and IceAGE. We see possible cryptic species, and we described to separate populations (and Arctic and one North Atlantic) of Rhachotropis aculeata.

Rhachotropis aff. palporum from IceAGE material. Fig 4G in Lörz et al, photographer: AHS Tandberg

Anne Helene has worked with Wim Vader from Tromsø Museum on Amphilochidae. The new species Amphilochus anoculus is formally described, and amphipod identifiers working with North-Atlantic material will be happy fo find a key to all Amphilochidae in the area. These minute and fragile animals are often lumped as family only, but the times for that are now over…

Key to the Amphilochidae from North Atlantic waters. Fig 14 from Tandberg & Vader 2018

Neighbour Joining tree of COI-sequences from IceAGE. The coloured lines on the side show possible interesting regions for further studies. Fig. 2 from Jazdzewska et al 2018

A paper on DNA fingerprinting of Icelandic amphipods is presented by Ania (who visited us two years ago to work on Phoxocephalid amphipods) and 10 coauthors. This study gives a very nice material to compare with the NorAmph barcodes, and some of the interesting results are discussed in the two first papers.

A summary-paper on the amphipod-families around Iceland (Brix et al) gives an overview of both biogeography and ecology of the amphipods in this area. This paper also presents faunistic data on Amphilochidae from the earlier BioIce project, where researchers from Bergen, Trondheim and Reykjavik sampled Icelandic waters.

Anne Helene

 

 

Literature:

Brix S, Lörz A-N, Jazdzweska AM, Hughes LE, Tandberg AHS, Pabis K, Stransky B, Krapp-Schickel T, Sorbe JC, Hendrycks E, Vader W, Frutos I, Horton T, Jazdzewski K, Peart R, Beermann J, Coleman CO, Buhl-Mortensen L, Corbari L, Havermans C, Tato R, Campean AJ (2018) Amphipod family distributions around Iceland. ZooKeys 731: 1-53 doi:10.3897/zookeys.731.19854

Jazszewska AM, Corbari L, Driskell A, Frutos I, Havermans C, Hendrycks E, Hughes L, Lörz A-N, Stransky B, Tandberg AHS, Vader W, Brix S (2018) A genetic fingerprint of Amphipoda from Icelandic waters – the baseline for further biodiversity and biogeography studies. ZooKeys 731: 55-73 doi:10.3897/zookeys.731.19913

Lörz A-N, Tandberg AHS, Willassen E, Driskell A (2018) Rhachotropis (Eusiroidea, Amphipoda) from the North East Atlantic. ZooKeys 731: 75-101 doi:10.3897/zookeys.731.19814

Tandberg AHS, Vader W (2018) On a new species of Amphilochus from deep and cold Atlantic waters, with a note on the genus Amphilochopsis (Amphipoda, Gammaridea, Amphilochidae). ZooKeys 731: 103-134 doi:10.3897/zookeys.731.19899

When amphipodologists meet.

It generally happens every two years. The event may be seen as a natural phenomenon – or maybe rather  a cultural phenomenon. I am sure it looks strange if observed from outside the community. A lot of people of all ages and affiliations meet up in places most of us usually did not even know existed, and we have the best week of our work-year.

Happy friends meeting in Trapani. (all photos: AH Tandberg)

Happy friends meeting in Trapani. (all photos: AH Tandberg)

The bi-annual International Colloquium on Amphipoda (ICA) is without doubt the scientific meeting I look most forward to.  Every time. The fun, the science, the amphipods, the friendships, the coffee, the familiar banter, the late nights and early mornings, the discussions – all in an atmosphere of friendship.

The Polish Amphipod-t-shirt edition 2017. (photo: AH Tandberg)

The Polish Amphipod-t-shirt edition 2017. (photo: AH Tandberg)

The first day of any ICA could be mistaken for a family-gathering – or the opening credits of any film about best friends. The room resounds of “oh – finally – there you are!”, “how are the kids/grandkids?”, “I missed you this last hour! Thought maybe you got lost since you weren’t here immediately” and not least “Come, let me give you that hug I promised!” Ten minutes later everybody will be organised by the large Polish group for some gathering or fun – and the rest of us are trying to find out how we can get one of the cool group-t-shirts the Łodz-group have concocted this year. Or maybe we should rather go for one of the other cool t-shirts picturing amphipods?

We do talk amphipods, of course. The incredible variety of the group (of animals – as well as people) opens up for a wide spectre of research-questions and approaches, and meetings allow time to learn from each other, get inspired, start new collaborations and share samples and ideas.

Most important: the science of amphipods. Loads of interesting talks and posters! (all photos: AH Tandberg)

Most important: the science of amphipods. Loads of interesting talks and posters! (all photos: AH Tandberg)

 

Those getting to the poster-session fast enough win the crochet amphipods... (photo: AH Tandberg)

Those getting to the poster-session fast enough win the crochet amphipods… (photo: AH Tandberg)

This years ICA was held in Trapani, Sicily – where prof Sabrina LoBrutto on a short one year notice had organised the meeting. The three days we met were packed with more than 60 talks, more than 60 posters and loads and loads of happy amphidologists. With the University situated right across the road from the beach, and a lunch hour long enough for both a coffee and a swim/sample search the friendly atmosphere stretched to drying towels on the railings of the university-hall and sea-salted hairstyles for many after lunch.

Keeping the atmosphere friendly: Beach, coffee and icecreams (all photos: AH Tandberg)

Keeping the atmosphere friendly: Beach, coffee and icecreams (all photos: AH Tandberg)

 

The scientifically helpful Japanese amphipod t-shirt. (now the rest of you should notice the morphological differences between the families). (photo: AH Tandberg)

The scientifically helpful Japanese amphipod t-shirt. (now the rest of you should notice the morphological differences between the families). (photo: AH Tandberg)

We always try to publish the Amphipod Newsletter to coincide with the ICA. You can download the newsletter both from the World Amphipoda Database and the Biodiversity Heritage Library (both places also have back-issues available for downloads). One of the features of the newsletter is a bibliography of amphipod-related literature, and a list of new taxa. Since last AN we have 79 new species, 14 new genera and 12 new families! Every AN includes an interview with one of the amphipodologists – this year you can get to know Wolfgang Zeidler and his Hyperiidea better.

The next ICA? In two years we meet in Dijon, France! I am already excited – and maybe there will be mustard-coloured t-shirts in honour of the location (or burgundy-coloured t-shirts)?  What I know already, is that it is going to be like meeting family.

Anne Helene

Evolutionary history of cave shrimps

Machumvi Ndogo - preparing for a dive in the dark

Machumvi Ndogo – preparing for a dive in the dark

In 2008 UiB colleagues Kenneth Meland and Endre Willassen surveyed karst caves in Zanzibar together with Hajj M. Hajj in search for aquatic crustacea. Many of these localities have so-called anchialine conditions in which marine water penetrates inland and can mix more or less with fresh ground water.

 

Atyid shrimps were sampled in salt water about 300 m inland from the coast.

Atyid shrimps were sampled in salt water about 300 m inland from the coast.

One of these sites had three species of small shrimps of the family Atyidae. The phylogenetic relationships of these shrimps have now been analysed by an international team of “cave men” based on full mitochondrial genome sequencing performed at the University of the Balears.

Molecular clock estimates date the relationship of the Zanzibarian species to other known species in the Atlantic and Indo-pacific  to the Cretaceous period.

Shrimps from Osine Cave

Shrimps from Osine Cave

The paper is available from this link:

https://www.nature.com/articles/s41598-017-03107-y

Species divergence history of the study group.

Species divergence history of the study group. Click for details.