dejayM's picture

Banded pincer weed

Observed: 17th October 2013 By: dejayM
Biological Recording In ScotlandHighland Biological Recording GroupOrkney Biodiversity Records Centre
dejayM’s reputation in PlantsdejayM’s reputation in PlantsdejayM’s reputation in PlantsdejayM’s reputation in Plants
host (egg Wrack) on rocks
on egg wrack
2cms scale
structure
close
clearly pincered
Ceramium virgatum
Description:

Another simple and very common seaweed, or so it seemed. Cluttering and massing epiphytically at the joints and stems of Egg Wrack (Ascophyllum nodosum) this looks quite brown, is a little brittle and with quite pointed ends. It is distinctly banded.
In the field, I had it pinned down to a Siphon Weed (Polysiphonia - say the expected P.lanosa ) UNTIL I looked in the Binoscope.
It then became a Ceramium and perhaps even C. virgatum. But then, to be certain, I followed up for a proper ID . A mistake!
...
26th Added Picture 6, which shows that Pincer Weed not only clusters at forks and joints but also seems to grow from the bladders themselves. See comments.
EDIT Added a Tag only (20/12.2014) Post origin 17th October 2013

Identifications
Species interactions

No interactions present.

Comments

dejayM's picture

ten minute rule

Origin 20 Oct 2013 - sorted H'link at the bottom
It seems unnecessary to try another ID just to get the ID Panel populated with links.
However, I see others have made it with Red Alga or, simply, Ceramium. I do so wish for the ten minute rule - that is 10 minutes to correct an ID fault! Ne're mind.
........
Even with the naked eye, the bifurcations can be seen and if one squints, the little pincers at the ends of some strands can be discerned.
Through the scope, the whole structure is revealed. Many of the pincers become closed, even overlapping and, whilst there were traces of tiny hairs it seemed pretty hairless, unlike the Siphon Weeds (Polisiphonia).
It seems unusual for this to be found on Egg Wrack (Ascophyllum nodosum), judging by Webmaterial but here it is absolutely prolific - IF I have the ID right!
Separating it from other species of Ceramium namely -
C.botryocarpum
C.pallidum (listed in Scapa Flow
C.secundatum (listed in Orkney)
C.deslongchampsii (listed in Scapa Flow)
C.diaphanum (listed in Scapa Flow),
C.virgatum (listed in Orkney seas)
C.cimbricum (listed in Scapa Flow)
requires stem sections, I cannot easily do that.
Here's someone who obviously could http://macoi.ci.uc.pt/spec_list_detail.php?spec_id=387&searchSpecies=cer...

It is both epilithic and epiphytic.

trudy-russell's picture

now small reds are not my

now small reds are not my speciality however I learnt one key thing from a red seaweed course with Juilet Brodie from the Natural History museum and that is it is commonly accepted that the fine red weed often found attached to ascophylum is polysiphonia lanosa however she has found that it is not actually a polysiphonia at all. She told us that it is in fact Vertebrata lanosa. see page on algal base http://www.algaebase.org/search/species/detail/?species_id=14086 im not sure on the key ID features but guess they are different from the polysiphonias. maybe this will help? or at least further your investigation

Trudy Russell
Marine Advisor
Natural England

To find out about what's going on in the south west check out http://www.ispot.org.uk/forum/8409

dejayM's picture

furthering

Yes Trudy, that's very useful thanks.
SeaSearch has FOUR pages of difficulty (Ceramium/Polysiphonia) - without mention of Vertebrata!

We also find that Polysiphonia lanosa is a pseudonym of Vertebrata lanosa. Under that name (V.lanosa), there seems to be more useful material on the WebThing.
There is a shortage of Microphotos on the web and in the books (except the Searsearch), yet we are told they require a m'scope to separate.

Beyond that, I spent an hour collecting little red 'featherweeds' (my expression) from the strandline today and have some very nice microphotos but cannot identify any but Red Cock's Comb - http://www.ispotnature.org/node/376096
I cannot give up yet!
This site http://www.algaebase.org/search/genus/detail/?genus_id=43020&-session=ab... lists 266 species of Vertebrata "of which 1 [only] has been flagged as currently accepted taxonomically"!
The pdf there looks inviting but only reveals a connection on page 338 (of 902); it is there that Fucus lanosa has one entry. So? Don't bother! But it turns out to be a lovely old book
NATURAL ARRANGEMENT OF BRITISH PLANTS,
ACCORDING TO THEIR RELATIONS TO EACH OTHER
AS POINTED OUT BY
JUSSIEU, DE CANDOLLE, BROWN, &c.

JoC's picture

Ceramium

I think this is a Ceramium. Which species will require further investigation. I will see what I can do...

I was surprised to read that P. lanosa is now V. lanosa, but thanks for the update., Trudy.

Jo

Jo

dejayM's picture

Pincers & grips

Well, that's comforting Jo.
I am now 2 days (about 58%!) more experienced and VERY nearby is an endless source of material - so I will try to get to grips and post more pics.
ð

http://www.bioimages.org.uk/html/r150930.htm
http://www.theseashore.org.uk/theseashore/SpeciesPages/Additional%20Spec...

JoC's picture

Following up

Following up is never a mistake - but it can be time consuming...
Ceramium: the one common factor seems to be the curled pincer apices combined with the striped appearance, so the genus is usually clear. Ceramium species are unusually morphologically variable. The cortical spines formed by some species are diagnostic, but this one seems spineless. In 1993 Maggs and Hommersand*** said that the non-spiny species were in a state of chaos in the British Isles and elsewhere. In those happy days of the 1990s I think we put them all in a ‘C. rubrum complex’. But having followed up your post, I now know better!
Current available field keys I have seen distinguish between plants which are fully corticated (axes covered with tiny cells as I think this specimen is) and those corticated only at the nodes.
In 2002 Maggs et al * said “Four fully corticated non-spiny species of Ceramium are currently recognized in the British Isles, all formerly confused under the illegitimate name Ceramium rubrum (Hudson) C. Agardh. Each of the four fully corticated species can be identified by morphological features, in particular the number of axial segments between branches.” However, I don’t have access to the full paper, so I don’t know what these are, but I think the 4 species proposed are C virgatum, C. pallidum C. secundatum and C. botryocarpum.
Another on-line source ** “Ceramium pallidum can be readily distinguished from the other species by its morphology (regular branching every 6-9 segments produces a fan-shaped pattern, together with strongly inrolled apices.). Ceramium virgatum differs from C. botryocarpum and C. secundatum by its irregular branching (every 10-18 segments) and the last two species can be separated anatomically by the number of periaxial cells (6–7 vs. 7–8 cells; Maggs and Hommersand, 1993)”.
When C. virgatum was known as C. nodulosum, Maggs & Hammersand *** said it was epiphytic on perennial algae and also epilithic.
So the choice is yours: on the evidence available I favour C. virgatum, but don’t let that influence you…
* C. Maggs, B.Ward, L. McIvor, C. Evans, J. Rueness and M. Stanhope. 2002 Molecular analyses elucidate the taxonomy of fully corticated, nonspiny species of Ceramium (Ceramiaceae, Rhodophyta) in the British Isles. Phycologia. Volume 41, Issue 4 (July 2002)
** CP DNA-RFLP in Ceramium (RHODOPHYTA):INTRASPECIFIC POLYMORPHISM AND SPECIES-LEVEL PHYLOGENY. Wattier, Davidson, Ward and Maggs. American Journal of Botany 88(7): 1209–1213. 2001
*** Maggs, C. & Hommersand, M. 1993. Volume 1 Rhodophyta; part 3a Ceramiales. HMSO

Jo

dejayM's picture

Second thoughts

That's a very thorough response Jo. Like you I was pretty convinced, less so now that I have spent more time alone with it.
What puzzles me is that I found it, in relatively huge swathes, attached to Egg Wrack/Knotted Wrack (Ascophylum nodosum), which seems to be rarely mentioned as a host, for anything other than Vertebrata/Polysiphonia.
If we assume that experts know best (we ought to) then Vertebrata lanosa is where we should go; the evidence, generally, is supportive to that end.

So, I WAS going to ID it as Ceramium rubrum, but this link, http://www.seaweed.ie/descriptions/Ceramium_virgatum.php always a very helpful site, appears to solve that difficulty by suggesting that Ceramium rubrum and Ceramium virgatum are also as one, that is C.virgatum.
All in all, I prefer to remain on the case and will hold off the ID for a while - there is no hurry to complete this particular journey.

JoC's picture

Thinking time is never wasted!

So take your time on this one.
Jo

Jo

dejayM's picture

Some certainty

I wanted to close this on a final note of acceptance - that it is (as Trudy intimated) Vertebrata lanosa.
BUT I am now certain that the pictures in her link are really NOT of the same.
If one compares my Picture 6 (via original) with ANY of the ones shown in >>THIS<< I think there is some doubt.
I need to collect some more and key it right out. Like Jo., I am inclined, still, to consider it Ceramium [virgatum]

dejayM's picture

Pincer grip

14 months on. What on earth can this be? So many convincing photos. So much information about THE epiphyte on egg wrack. So little confidence beyond JoC. I'm worried about the future of seaweeds in iSpot! See >>A SEAWEED PROJECT UK<<The shore here is thick with this, it is common, prolific and laden with ID features.
Can it be Ceramium virgatum? Yes, it could. But does that occur prolifically on egg wrack? No!

JoC's picture

epiphyte ID

The phrase " Ceramium virgatum, for example, is almost ubiquitous as an epiphyte" occurs often in the literature. I don,t see why it should not be found on Ascophyllum. However, any red seaweed on A. nodosum is usually id'd as P. lanosa. Whoever thought to look closer?

Jo

dejayM's picture

and back again

More information has come to light. I posted a picture 'in another place' and a well known 'expert' says (of it) "Branching interval range correct for C. virgatum"
I have added a picture which shows a rehydrated portion, so shows it to be previously somewhat desiccated - I think it loses colour quite quickly when dry.

JoC's picture

C. virgatum

It seems we are agreed on the species; will you post the id?

Jo

dejayM's picture

Long trail

Why have I marked it as 'It might be this'?. Well I'd say it is difficult to be certain of anything where 'minor' marine algae is concerned. I have more than enough books, yet I have ordered another today♪; I know how to use the web to advantage; I am a subscriber to a pretty impressive closed group of like-minded, yet diversely-thinking phycologogists; I lean on one of the VERY few people in iSpot who is prepared to be firm, advisory and is usually correct! And yet, yet, I could be more confident!
However, I have proposed C.virgatum because it has been suggested by an expert, another real one and I need to learn to trust real experts!
However, I think this particular post has run its course, so I will use my recently developed forensic approach to make a new one featuring the same alga and see if I cannot be As sure as I can be

http://www.nhbs.com/title/157360/green-seaweeds-of-britain-and-ireland