An online guide to the Stalked jellyfish (Stauromedusae) found
around the coastal waters of the United Kingdom and Ireland.
Includes notes on their identification, and where and how to find them.

News, accounts and records from around the UK
Please feel free to contribute - e-mail.

Novemeber 2016
It's not everyday that you see a stalked jellyfish that lacks the usual orange, red, green or brown pigment. So when something like this appears on Social Media, it's a real eye opener! This unpigmented specimen of Calvadosia campanulata, was found by Kent Wildlife Trust in Thanet in the summer of 2016, and what a beautiful thing it is.
Please Note - Image copyright Kent Wildlife Trust.

September 2016
WoRMS edited by Dr. Allen Collins. Genus change for Lucernariopsis cruxmelitensis Corbin, 1978 and Lucernariopsis campanulata (Lamouroux, 1815) to Calvadosia.

This follows the publication of Systematics of stalked jellyfishes (Cnidaria: Staurozoa) Lucılia S. Miranda, Yayoi M. Hirano, Claudia E. Mills, Audrey Falconer, David Fenwick, Antonio C. Marques and Allen G. Collins. 2016.

January 2016
 Mounts Bay in Cornwall is now partly a Marine Conservation Zone, this is good news for stauromedusae, but even better news for the marine biodiversity and habitat in the area, all be it providing MCZ status doesn't increase the level of human impact in the area, which is a serious concern given the number of visitors to St. Michael's Mount and its good access for marine groups etc. who might want to use the MCZ as an outdoor classroom. All we can hope is that the area can be managed appropriately and go back to human impact levels pre. the rMCZ evidence gathering process, or less. All stakeholders need to come together to achieve this, and I'm glad to say that tourism and visitor numbers to the Mount isn't really an issue. I'm personally hoping that sustainable potting for shellfish will be allowed in the MCZ, crabs do a lot of damage to the reef systems which might be further broken up by storms. We need the reefs to conserve stalked jellyfish / stauromedusae.

September 2015

15.09.15 A ripe male Calvadosia campanulata was found at Constantine Beach, North Cornwall, specimen produced sperm on being kept in a dark fridge. For image set see Species account for Lurcernariopsis campanulata.

January 2015

06.01.15 Stauromedusae and turbidity monitoring of Penzance Harbour by ECOSPAN ENVIRONMENTAL LTD, has turned up a very rare twin-headed specimen of Haliclystus octoradiatus (click for larger image) at Albert Pier reef. David Fenwick, who was present when it was found stated, this is the likely to be the first reported specimen of a twin-headed Haliclystus octoradiatus, so well done Greg Lingard of ECOSPAN for finding it. Twin-headed stalked jellyfish are very rare indeed and probably less than a dozen have ever been reported in stauromedusae of the past 200 years.

On the occurrence of twin-headed specimens
of stauromedusae by David Fenwick

Happy New Year Everyone

November 2014

24.11.14 Ecospan Environmental start monitoring stauromedusae at Albert Pier Reef, Penzance, Cornwall; and at a control site at Great Hogus reef, near Marazion. Monitoring takes the form of 20 minute timed surveys by two people in three pools at each site. Monitoring to take place in the same three pools on a regular basis until March 2015. This is taking place to ensure stauromedusae, a protected species, and their habitat, are monitored closely during the capital dredge of Penzance Harbour, which is situated close-by.

23.11.14 26 Stalked Jellyfish found in the Marazion part of the Mounts Bay rMCZ. 14 Calvadosia campanulata, 4 Calvadosia cruxmelitensis and 8 Haliclystus octoradiatus.

11.11.14. The first Haliclystus octoradiatus of the forthcoming season was found in a middleshore pool at Albert Reef, Penzance, Cornwall. Carol Tucker.

10.11.14 Author of this website meets with the Project Manager of the Isles of Scilly Link Project to discuss the protection of habitat important for three UKBAP species of stauromedusae close to Penzance Harbour, Penzance, Cornwall; which is to be dredged. I am pleased to say that monitoring of turbidity and the stauromedusae habitat is now planned and will be carried out throughout the project. Here I must thank all involved including Cornwall County Council, Mace Group and Peter Madsen Rederi A/S, the dredging contractors. Four species of stauromedusae are protected by legislation in the UK, and by the NERC Act 2006, which protects UKBAP / S41 listed species.

05.11.14 Thirteen Calvadosia campanulata found at Albert Pier Reef, Penzance, Cornwall. Most condensed on the lowershore and close to low water, but a couple smaller individuals in middleshore pools. Weather, showery with bright spells, south / south westerly wind for some time and average land temps higher than normal. David Fenwick.

Lat. / Long. Exif GPS IDF data
50.120335°N 5.530027°W
50.120443°N 5.52978°W
50.120257°N 5.529877°W
50.120553°N 5.529843°W
50.120553°N 5.529843°W
50.120307°N 5.530043°W
50.120335°N 5.530027°W
50.120238°N 5.530213°W
50.120078°N 5.529948°W
50.120117°N 5.53006°W
50.120482°N 5.530327°W
50.120498°N 5.530432°W
50.120552°N 5.530502°W

October 2014

11.10.14 Approx. twenty Calvadosia campanulata found at 2nd Barrier, Orkney. Penny Martin.

September 2014

Numerous reports now being received for Calvadosia campanulata, Craterolophus convolvulus and Haliclystus octoradiatus, the new season appears to have begun.

27.09.14 One Craterolophus convolvulus and one Calvadosia campanulata found in a lowershore pool near Godrevy Point, Gwithian, Cornwall. David Fenwick.

11.09.14 Unusually shaped Craterolophus convolvulus discovered by Rob Durrant. Image ©Rob Durrant.

10.09.14 Two Calvadosia campanulata found in pools at west Fistral, Newquay, Cornwall. One specimen found on Ceramium another on Sea lettuce. David Fenwick.
50.413182°N 5.105612°W
50.413135°N 5.105167°W

10.09.14 Haliclystus octoradiatus and Calvadosia campanulata found at Hele Bay, North Devon. Janice Whittington.

08.09.14 12 Haliclystus octoradiatus and 4 Craterolophus convolvulus found in pool west of the lifeboat station at Sennen Cove, Cornwall.

August 2014

13.08.14 One Calvadosia campanulata found on reef at eastern edge of Newton's Cove, Weymouth, Dorset. Carol Tucker.

July 2014

29.07.14 One juvenile Haliclystus octoradiatus found in main lowershore gulley at Battery Rocks, Penzance, Cornwall. Conditions sunny, a lot of decaying red and green algae at site.

28.07.14 Three Haliclystus octoradiatus found in lowershore pool south of Mousehole Harbour. Specimens were found in the same pool and were approx. 5mm, 10mm and 20mm dia.. Conditions overcast, light showers, sunny spells later in day. Algae not decaying in pools.

Article -
Notes on stauromedusae at Port Erin and other
reported Isle of Man sites. David Fenwick. 2014.
A search for Depastrum cyathiforme.

Have just produced a map outlining recording dates and records of Depastrum cyathiforme for the UK and Ireland, as there are no records currently on the NBN Gateway. (author). So many old records, the last record for the species to date was for Lundy in 1951. Anyone up for the challenge of finding the species?

Distribution map of Depastrum cyathiforme

Also see - Species Account for Depastrum cyathiforme

May 2014

General decline in records for Haliclystus octoradiatus and Calvadosia cruxmelitensis from South Cornwall, because of seasonality of stauromedusae, must also be noted that May has been quite a sunny month.

April 2014

27.04.14 Article "On the occurence of twin-headed specimens of stauromedusae." added to Stauromeduisae UK.

11.04.14 Orkney Islands. Haliclystus auricula. 2nd Barrier. Specimens found whilst snorkelling, found on Ulva, Cladophora rupestris and Osmundea hybrida. Penny Martin.

04.04.2014. Cornwall. Albert Pier Reef, Penzance. SW4777830415. 5 specimens. 2 Haliclystus octoradiatus and 3 Calvadosia cruxmelitensis. All but one specimen in lowershore pools on the low tide mark. Carol Tucker.

03.04.2014. Cornwall. Fistral Beach, Newquay. 2 specimens. Two Haliclystus octoradiatus found on algae Cystoseira, by Matt Slater, during a Shoresearch event at the beach. Matt Slater (Marine Awareness Officer) Cornwall Wildlife Trust.

03.04.14. Cornwall. Battery Rocks, Penzance. SW47722976. 17 specimens. 15 Haliclystus octoradiatus and 2 Calvadosia cruxmelitensis. Good weather conditions, thin cloud, light winds. Specimens only found on Chondrus crispus, only found in the middle section of the main gully that divides the reef and despite there being suitable habitat and algae elsewhere on the reef. One of the two Calvadosia cruxmelitensis, a small specimen, was found on Chondrus crispus at Chimney Rocks, just west of Battery Rocks. Chimney Rocks, SW47562979, was not searched for stauromedusae. All specimens photographed and geotagged. The area around Battery and Chimney Rocks suffered extensive damage from storms during the winter of 2013/14. Damage to the lowershore by comtemporary wave quarrying was quite obvious at Battery Rocks. The last storm was given the name the Valentine's Storm and waves up to 90 feet high were recorded in the area. The same area was surveyed on 09.04.13, 9 specimens were found, the included 8 Haliclystus octoradiatus and 1 Calvadosia cruxmelitensis, the survey was conducted in quite poor conditions. See record below. David Fenwick.

02.04.14. Cornwall. Long Rock, near Penzance. SW49753092. 48 specimens. 7 Calvadosia cruxmelitensis and 41 Haliclystus octoradiatus. Lowershore reef mostly on Chondrus crispus, Gracilaria gracilis and other species of red algae. 6 specimens seen feeding. Pools seen to be drainining into one another as other good stalked jellyfish sites in the bay. There was considerable storm damage and sediment removal from beach during 2013/14 storms, especially the Valentine Storm. Gracilaria gracilis is now recolonising and Haliclystus octoradiatus is taking advantage of this and moving further up the shore, where there was once sand. No stauromedusae were observed on the west side of Long Rock reef, or its Eelgrass bed, there is though, extensive damage to the habitat. David Fenwick. See details of record.

March 2014

31.03.14. Cornwall. Reefs east of St. Michael's Mount Causeway, Marazion. Approx. 70 specimens. 6:1 Calvadosia cruxmelitensis to Haliclystus octoradiatus. 1 Calvadosia campanulata observed at SW 518 302, which was millimetres from a Calvadosia cruxmelitensis. Both UK species of Lucernariopsis. No individual records kept of other species. Stalked jellyfish were mainly observed in front of Marazion Harbour, SW51893039; and east of St. Michael's Mount causeway, SW51723018. David Fenwick, Carol Tucker and Dr. Keith Hiscock of the Marine Biological Association.

29.03.14. Cornwall. Reef east of St. Michael's Mount Causeway, Marazion. 21 specimens, including 1 Craterolophus convolvulus and 1 Calvadosia campanulata during PANACHE shore survey and training session. Matt Slater (Marine Awareness Officer) Cornwall Wildlife Trust.

19.03.14. Cornwall. Top Tieb, Marazion. 61 specimens. 45 Calvadosia cruxmelitensis, 15 Haliclystus octoradiatus and 1 Craterolophus convolvulus. Lowershore; mostly on Gracilaria gracilis, in stoney and sandy bottomed pools. Site profile.

18.03.14. Cornwall. Shore below Marazion Harbour, Marazion. 48 specimens. 28 Calvadosia cruxmelitensis and 20 Haliclystus octoradiatus. Lowershore; on a small area of shore in front of Marazion Harbour. Site profile.

16.03.14. Cornwall. Little London, Marazion. SW 5263 3028.
21 specimens. 1 juvenile 4mm dia. Craterolophus convolvulus, 6 Calvadosia cruxmelitensis and 14 Haliclystus octoradiatus. Largely on narrow band of Chondrus crispus covered reef in pools close to or at the low water mark. David Fenwick. Site profile.

15.03.2014. Cornwall. The Greeb, Perranuthnoe. SW5333329292; and Boat Cove. 20 specimens. 18 Haliclystus octoradiatus and two juvenile Lucernaria cruxmelitensis. Numbers present could indicate a smack, or large congregation of Haliclystus octoradiatus in the area. The highest frequency of Haliclystus octoradiatus was on the lowershore on the low tide line, the specimens here were also larger than those further up the shore. The site would seem to be extremely good for stauromedusae, lots of currents created by The Greeb, good levels of Chondrus crispus in pools running down to the lowershore in line with The Greeb, other algae species present were quite suitable. Could be quite an important site despite it being quite exposed. More than twenty specimens would have been recorded if it wasn't for the need to photograph and get GPS data for each individual specimen. Time might have been best spent calculating frequency and number of specimens per ten meter square. The Greeb falls within the proposed Mounts Bay Marine Conservation Zone. David Fenwick. Site profile.

14.03.2014. Cornwall. Great Hogus reef, Marazion. SW513305. 8 specimens. Two Calvadosia cruxmelitensis and six Haliclystus octoradiatus found in pools on the reef. See "Great Hogus site profile" for further details of the site and stauromedusae records. David Fenwick. Site profile.

07.03.2014. Cornwall. Sennen Cove, West Cornwall. 4 specimens. Searched for Craterolophus convolvulus, none were found, not even in the usual pools, this isn't surprising given the recent storms and the exposed nature of the site. It wasn't too long ago when images were beamed around the world of waves crashing over the cliff at Sennen Cove. Three Haliclystus octoradiatus were found, in pools on the lowershore, under the outer harbour wall, where it is more sheltered. SW3508026432. Another Haliclystus octoradiatus was found in a middleshore pool on Corallina officinalis just north of the lifeboat station. SW3515726395. It is amazing how these animals have survived storms like the Valentine Storm at this location. David Fenwick.

03.03.2014. Cornwall. 20 specimens on Eelgrass bed, east of St. Michael's Mount causeway, Marazion, Cornwall; a site within the proposed Marine Conservation Zone, MCZ. Site visit was to assess level of damage to the Eelgrass bed after extremely severe and frequent winter storms. Site was found to be battered but largely intact, compared with Long Rock Eelgrass bed, which has been devastated.

12 Haliclystus octoradiatus, 5 Calvadosia campanulata and 3 Calvadosia cruxmelitensis were found at the site, all specimens were found within a 10m x 10m square at SW5173330200.

19 of the 20 specimens were found on Chondrus crispus that occurs on rocks in shallow pools on the Eegrass bed. A single specimen of Haliclystus octoradiatus was found on Polyides rotundus, Goat tang.

Of the Haliclystus octoradiatus specimens found, two were large and fully mature, and others were approximately 10mm in diameter across the bell.

One Calvadosia cruxmelitensis specimen was 6mm diameter across the bell, the others 11mm and 13mm dia.. All of the typical colour and the Maltese Cross arrangement of nematocysts was clearly seen. The smallest specimen was determined microscopically.

Two medium-sized Calvadosia campanulata specimens were found, another was of approx. 10mm diameter across the bell and there were two 4mm diameter specimens. The latter appeared to be Calvadosia campanulata on site, because of their intense red colour, one was taken for microscopic determination, which confirmed this species.

All the species here were found in an around of considerable water movement, from west to east across St. Michael's Mount Causeway, but site was guarded by a low outcrop of rock. The most significant thing about this record is that during the past seven days only three Haliclystus octoradiatus have been found at Albert Pier Reef after a long period of recent storms, this is a low number for the site. Calvadosia cruxmelitensis was not recorded at the site which is unusual. Similarly two days previous to this record, Long Rock Eelgrass bed was found to have been severely damaged by storms, and the storms may have reduced the size of the bed by up to 50%, there were no stauromedusae records.

Considering all the unusual amounts of storm damage and low numbers of stauromedusae currently in Mounts Bay, it appears that the Eelgrass bed and habitat at St Michael's Mount causeway has largely been protected from southerly and south-westerly winds and storms, and as a result, provided a protected haven for Stalked jellyfish.

This is a longer than normal account due to the fact that the site falls within the proposed Mounts Bay Marine Conservation Zone. David Fenwick.

02.03.2004. Cornwall. Site visit to Long Rock, Penzance, to assess level of damage to the Eelgrass bed after severe and frequent winter storms. Eelgrass bed has been severely damaged and reduced by up to 50%. What affect this will have on the local population of stauromedusae is unknown! Cornwall Wildlife Trust plan to snorkel over the bed and map the extent of the damage during the summer. David Fenwick.

01.03.2014. Cornwall. Site visit to Albert Pier Reef, Penzance to assess site for damage after recent severe and frequent storms. Erosion of seafloor in places, and deposition of sediment across the reef, more on the lowershore than the middleshore, which supports most stuaromedusae species. Reduced numbers of stauromedusae in pools because ''all'' species of algae have been cropped short by storms. Three medium sized, approx. 10mm Haliclystus octoradiatus were found, but more would have been expected at this time of year. Calvadosia cruxmelitensis appeared to be absent, very unusual for this site, which is a good site for the species because of the frequency of Chondrus crispus and Corallina officinalis. David Fenwick.

January 2014

21.01.2014. Cornwall. A Coral weed, Corallina officinalis, sample was looked at using a stereo microscope. The sample was taken on 20.01.14 from a middleshore pool at Albert Reef, Penzance, Cornwall. SW4777830415. The sample was taken to identify marine microfauna, it was found to contain a 4mm long specimen of Calvadosia cruxmelitensis. David Fenwick.

20.01.2014. Cornwall. Albert Reef, Penzance, Cornwall. SW4777830415.
One mature Calvadosia cruxmelitensis found on red algae Calliblepharis jubata, another mature Calvadosia cruxmelitensis on brown algae Sargassum muticum. Four juvenile Haliclystus octoradiatus, one on red algae Calliblepharis jubata and three on Sargassum muticum. Good conditions for searching, little wind, surprised to find any Stalked jellyfish at all after recent stormy weather. Storms have caused some damage to habitat, algae have been well cropped, and a lot of sediment washed into rockpools. Stalked jellyfish were sporadic in rockpools across the reef rather than being in predictable and usual rockpools. Camera used Pentax WG-III. David Fenwick.

June 2013

02.06.2013. Cornwall. Haliclystus auricula, recorded in good numbers by Penny Martin from east side of 2nd Barrier 58, 53.0 N 02 54.4 W. Orkney Islands. Record confirmed by Marco Faasse and David Fenwick. See images of Haliclystus auricula.

April 2013

09.04.2013. Cornwall. Battery Rocks, Penzance, Cornwall.
A site survey was carried out at Battery Rocks on the 9th April 2013 in relation to the proposed dredging at Pezance Harbour. Despite bad weather, eight Haliclystus octoradiatus and one Calvadosia cruxmelitensis were found, mostly in the main gulley running east to west across the lowershore. Species were found mainly on Chondrus crispus but other algal species involved. Haliclystus octoradiatus also found in lowershore coralline pools.

Haliclystus octoradiatus
1- SW4774029802 on Chondrus crispus
2- SW4772729793 on Chondrus crispus
3- SW4772829777 on Chondrus crispus
4- SW4772829775 on Gastroclonium ovatum
5- SW4771429783 on Chondrus crispus
6- SW4771729787 on Palmaria palmata
7- SW4772029793 on Chondrus crispus
8- SW4771629852 on Calliblepharis ?

Calvadosia cruxmelitensis
1- SW4772729801 on Chondrus crispus

1. No stauromedusae observed on Sargassum muticum.
2. Stauromedusae not as high up the shore as previously observed at site, might be related to recent strong SE winds.
3. Haliclystus octoradiatus widespread across search area.
4. Despite lack of pools on the eastern side of the search area, which mainly consists of gulleys with Fucus serratus. There was a lot of suitable red algal species for stauromedusae, species such as Chondrus crispus, observed just beyond the low tide mark.
5. There were no small Haliclystus octoradiatus found on the Ceramium species that fringe some of the middleshore pools. Amounts of Ceramium sp. seen were less than normal.
David Fenwick.

March 2013

30.03.2013. Cornwall. Long Rock, Penzance. Cornwall. SW4983030920. Just one 10mm diameter Haliclystus octoradiatus found. Surprisingly only one stalked jellyfish found. SE winds have had a huge effect on sediments over the entire eelgrass bed lots of changes to the habtat. Lots of dessication of eelgrass, where the eelgrass has been exposed to elements. Submerged eelgrass doing well in certain areas considering the weather conditions. David Fenwick.

February 2012

09.02.12. Cornwall. Battery Rocks, Penzance, Cornwall.
A 10m long lowershore pool provided the following records by David Fenwick.

1 x Calvadosia cruxmelitensis, St John's stalked jellyfish SW4769929759, on Chondrus crispus.
1 x Haliclystus octoradiatus SW4769829757.
2 x Haliclystus octoradiatus SW4771129761 on Chondrus crispus.
1 x Haliclystus octoradiatus SW4769529757 - on bedrock of a rockpool.

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Stauromedusae Stalked jellyfish News Accounts Records Recording UK