The Essex Harbour Porpoise Phocoena phocoena L, 2003 survey
by blows from their tail. Live animals should never be handled. Contact the RSPCA (tel. 0990
555999).
If you find a fresh cetacean corpse, secure the carcass above high water or anchor it securely.
Always wear gloves if handling cetacean corpses and contact the coastguard. Freshly dead animals
are sent for post mortem to the British Museum to establish a cause of death, provide information
on age and reproductive status and tissue samples are analysed for pollutants, heavy metals and
other contaminants.
All sightings and stranding records have been forwarded for inclusion into the national database at
Oxford University. All information is important in building up a picture of our cetacean populations.
Please pass on any sightings information to Mark Iley, Essex Biodiversity Project
Tel. 01621 862975 or marki@essexwt.org.uk
Acknowledgements
The Essex Biodiversity Project is a group of more than 40 nature conservation organisations, statutory
agencies, voluntary interest groups, businesses, community groups and local authorities working
together for the biodiversity of Essex.
The project would like to thank everyone who submitted records, deployed and downloaded the
POD and helped to collate information, particularly Ian Black, Tony Douglas, Tony Haggis, Malcolm
Hardy and Gary Mead - their participation is greatly appreciated.
Ero aphana (Araneae: Mimetidae), a spider new to Essex
PETER HARVEY
32 Lodge Lane, Grays, Essex RM16 2YP
In 2003 two females of the rare pirate spider Ero aphana (Plate 5) were collected new to Essex on
two separate occasions at Anchor Field (TQ591779), a site adjacent to Lakeside Retail Park in
Thurrock, S. Essex. These occurrences were unexpected, and indicate that it is almost certainly
established at the site.
Ero is the only genus of the family Mimetidae found in northern Europe. The metatarsi and tarsi of
the first pairs of legs are armed with a series of long spines alternating with short ones. They spin
no web of their own, but seek out the webs of other spiders. Here they pluck the threads to deceive
the occupant into believing they arc caught in the web, and when it investigates it is attacked,
quickly paralysed and then sucked dry through a small hole in the legs. E. aphana has two pairs of
tubercles on the abdomen, the rear pair being smaller and less widely separated than the related E.
tuberculata, a Nationally Scarce spider with few records in Essex.
Ero aphana was first recorded in Britain in 1974 (Merrett & Snazell 1975). Since 1974 the species
has been recorded from a number of sites in Dorset. It has also been found at Cranes Moor in the
New Forest and as probable juveniles at two other sites in Hampshire, as well as at Chobham
Essex Naturalist (New Series) 21 (2004)
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