Friday mystery object #296 answer

Last week I gave you this lovely little shell to try your hand at identifying:

mystery296

It’s a specimen that was given to the Dead Zoo recently by a regular contributor to the collections and it’s particularly interesting because it might be the first record of this species in Ireland (this is currently being researched for publication by the donor, so I won’t give away too much detail).

What I will say is that this is one of the reasons species identifications can be very important, since our understanding of how species move around has implications for various aspects of society and you don’t want to make decisions based on bad information. If you don’t know what I mean by that, I’ll give you some examples.

Zebra mussels arrived in Ireland in the 1990s from the Black and Caspian Seas and they’ve bred prolifically. They altered freshwater ecosystems by filtering out plankton that other species depend on for survival and they form hard-to-remove clusters that foul boat hulls and block drainage and cooling pipes. They’re in North America too, and in 15 years they are estimated to have cost hydroelectric and water treatment plants somewhere in the region of $267 million to remove or defend against. It’s cheaper to defend against them than to remove them and fix the problems they cause, so you need to know what you’re dealing with.

Retrieval of zebra mussel-encrusted Vector Averaging Current Meter near Michigan City, IN. Lake Michigan, June 1999. Photo by M. McCormick, NOAA, Great Lakes Environmental Research Laboratory

Retrieval of zebra mussel-encrusted Vector Averaging Current Meter near Michigan City, IN. Lake Michigan, June 1999. Photo by M. McCormick, NOAA, Great Lakes Environmental Research Laboratory

Signal crayfish are another freshwater invasive species, this time from America, that have caused havoc in Europe because they are linked to the dreaded Crayfish plague (I kid you not). The American crayfish are resistant to this fungal(ish) disease, but they act as hosts and carriers. Ireland is the last country in Europe to be free of the invasive crayfish, but are constantly alert to the dangers they can pose to the native species.

Signal crayfish by David Perez, 2009

Signal crayfish by David Perez, 2009

I should say that the many introduced species aren’t actually all that problematic. I’ve not heard that Little Owls (introduced by the Victorians for the cuteness) or Ring-necked Parakeets (escapees from aviaries) have had any significant impact in the UK. Still, it’s interesting to know when species turn up somewhere, especially if it reflects a change in the environment that may have other impacts.

Little Owl by Arturo Nikolai, 2008

Little Owl by Arturo Nikolai, 2008

Noble False Widow spiders were a harmless addition to the UK fauna back in 1879, that were quietly tucked down in Devon until the changing climate gave them the conditions to move further north. Now they’re up as far as Liverpool thanks to our warmer winters. Similar patterns are seen for a variety of Mediterranean species, demonstrating how we can track changes in our environment by keeping track of where and when certain species are found – but if you don’t get the species right, you don’t have good data. That’s part of why we have museums in the first place, to lodge ‘voucher’ specimens of recorded species so identifications can be double checked in the future.

Steatoda nobilis, Forest Hill, London, by Paolo Viscardi, 2014

Noble False Widow

Of course, I’m sure that you all appreciate the importance of getting identifications correct, since here you are reading my blog which tends to be all about identification! For those of you who recognised the mystery object as a scallop of some sort I tip my hat, but to Daniel Jones I offer congratulations – this is indeed a Calico Scallop Argopecten gibbus (Linnaeus, 1767) which is, as Joe Vans suggested, a juvenile. Normally these are found on the Atlantic coast of America. Well done! I’ll let you know more about the specimen when the paper is published.

More interesting dead stuff to come next Friday…

Friday mystery object #296

This week I’ve been in the USA couriering a loan back from the stunning Corning Museum of Glass (I’ll write about that sometime soon). However, that means I’ve had limited access to specimens for this week’s mystery object and I’m restricted to what I’ve got on my phone. Fortunately, I have this non-vertebrate mystery object for you to try your hand at identifying to species:

mystery296

It’s quite a cool specimen and I’ll tell you why next week! Have fun!

Friday mystery object #255 answer

Last Friday I gave you this rather interesting looking object to identify, preferably using a rhyme:

wpid-img_20150626_095757-1_20150626095918070.jpg

Believe it or not the photographs show either side of the same object – on one side it just looks like a rugose lump and on the other it shows a rather nice natural spiral.

Aside from some great humorous comments by 4utu and Henrik Nielsen, there were some of you who worked out that this is the operculum from a marine snail and even managed to explain that in rhyme – so very well done to Barbara, Chris and especially Lee Post who upped the ante by writing a full verse:

oh purr Q lum from foreign shores
possibly from a near ites door
side door -back door does not exist
main door -strong door , built to resist

Flick Baker went a step further (taxonomically) by identifying that this operculum is from a snail in the genus Turbo with the rhyme: “Gives your engine serious puff, even when she’s running rough“.

Green Turban Shell (Turbo marmoratus) showing aperture closed by the operculum

Green Turban Shell (Turbo marmoratus) showing aperture closed by the operculum

More specifically, this operculum is from the South African Turban Shell Turbo sarmaticus Linnaeus, 1758.

The operculum is a part of many snails that is often forgotten about – it forms a protective trapdoor that the snail closes behind itself when it retreats inside its shell (‘operculum’ means ‘cover’ or ‘lid’ in Latin). This trapdoor helps prevent desiccation in land snails and helps protect against predators in marine snails.

When the animal dies the operculum will often fall off as the body of the animal decays or is eaten, so often it won’t find its way into a museum collection with the rest of the shell. However, opercula can be quite distinctive and are sometimes more useful for identifying a species than the rest of the shell – a handy point to remember.

Friday mystery object #199 answer

On Friday I gave you this rather beautiful object to identify,which came to light during our mollusc Bioblitz last week:

mystery199

It turns out that it didn’t prove much of a challenge and was identified to species level in no time. So well done to Kevin, Anna Pike, @benharvey1 and Carlos Grau!

In fact, Carlos went a step further than identifying the specimen and told the very story I was planning to tell in this post. It’s great to hear stories like this about specimens or species, so I’ll share it with you in Carlos’ words:

This picture immediately brought back memories of my old seashell-collecting guide I had when I was about 12 and haven’t looked at for years and years (I will look for it next time I’m at my parent’s). The book said that this species was considered so valuable that fakes were made in rice paste by Chinese artisans, and that the counterfeits are now more rare and valuable than the actual shell! I remember finding that bit of information amazing.

It’s been so long I had to Google the book, it’s “Guide to Seashells of the World” by R. Tucker Abbott.

The animal is… Continue reading

Friday mystery object #130 answer

On Friday I gave you this specimen to identify:

I thought that some of you might find it a bit tricky, since this is a shell from a group of animals that aren’t that familiar to most people.

Barbara Powell was the first to spot what this shell came from and her identification was supported by Dave Godfrey, Julie Doyle and henstridgesj. It’s a   Continue reading