- filtered for Great Britain (Mainland)
Images and Species Descriptions
Text and photographs © 2011 Jørgen Lissner
The Spiders of Europe and Greenland
Family: Mimetidae (Pirate Spiders)
Biology: The common name “pirate spiders” refers to them being predatory on other spiders. They spin no web but stalk or ambush their prey. Often the web of a potential prey spider is invaded. Sometimes the prey spider is lured to advance towards the pirate spider, which plucks the thread to imitate a lovesick male. The pirate spider then bites the prey spider, usually in a leg and then sucks it dry through the hole bitten. Pirate spiders are slow moving, perhaps an adaptation not to scare potential prey spiders in the vicinity or maybe to avoid triggering aggressive behaviour such as the pirate spider becomes the prey instead. The European members of the family are characterized by long legs, which often are clearly annulated.
Characters of family: Metatarsi I and II are furnished with a prolateral row of spines. In between the spines there are series of smaller curved spines, which increase in length distally.
Genus: Ero C. L. Koch, 1836
Characters of genus: The species of this genus resemble comb-footed spiders (Theridiidae) due to their globular abdomen, which is higher than long. The abdomen bears one or two pairs of conical tubercles. The dorsal parts of the abdomen are furnished with curved bristle-like hairs. The anterior medial eyes projects on a small tubercle. The distance between the anterior edge of the carapace and the anterior medial eyes (height of clypeus) is about the same as the distance between the anterior and posterior medial eyes. The length of leg I is slightly less than 1⅓ times that of leg IV. The two commonest Danish species of the genus, E. furcata and E. cambridgei, are difficult to separate as they overlap both in general appearance and habitat. The carapaces of the species are light yellowish brown with variable blackish lateral bands, which often reach the margins. I the midline and especially the eye region there are additional irregular blackish markings. Since these markings on the carapace are quite similar for the species, they are not useful for separating the species. The egg sacks of Ero are very characteristic. The more or less egg-shaped sack is about 4 mm in diameter, and made of yellowish brown silk which is surrounded by loosely woven silk of a darker colour giving the sack a woolly appearance. The sack is suspended by a cord of silk about 1-2 cm long, typically fastened to vegetation, including branches and bark of trees. The sacks are not guarded but abandoned by the female, which set out for more prey to be able to produce more egg sacks. Since Ero species are nocturnal, and remain hidden during the daytime, the egg sacks often reveal the presence of the species before specimens are found.
Ero aphana (Walckenaer, 1802)
Description: Abdomen overall whitish with brown spots. There are two pairs of conical tubercles of which the posterior pair usually is slightly larger than the anterior pair. This character separates the species from E. tuberculata in which species the two pairs of tubercles differ clearly in size. Sternum dark with droplet-shaped radiating light markings in posterior half and a larger irregular light marking in the anterior half. Size: Female 2.5-3.2 mm; male 2.4-2.6 mm. Maturity: Both sexes are adult from May to July. Adult females are also encountered in August. Habitat: Bushes and low vegetation in warm places. At the northern limit of its distribution it is mainly found on heather and other low vegetation in heathlands. Further to the south of Europe the species occupy more diverse habitats, including coniferous forest and forest edges where specimens can be swept from the lower the branches of trees and bushes. The species may also be encountered in parks and gardens. Range: Andorra, Austria, Belgium, Bulgaria, Croatia, Czech Republic, Denmark, France (Corsica), France (Mainland), Germany, Great Britain (Mainland), Greece (Crete), Greece (Dodecanese Islands), Greece (Mainland), Hungary, Italy (Mainland), Italy (Sardinia), Liechtenstein, Netherlands, Poland, Portugal (Azores), Portugal (Madeira), Portugal (Mainland), Romania, Russia (Eastern European), Russia (Southern European), Slovakia, Slovenia, Spain (Balearic Islands), Spain (Canary Islands), Spain (Mainland), Switzerland, Ukraine, Yugoslavia (van Helsdingen 2009.1). Global range: Palearctic (St Helena, Queensland, introduced) (Platnick 10.0).
Male.
Female.
Subadult male (id?).
Subadult male (id?).
Abdominal markings, subadult male (id?).
Subadult male (id?).
Subadult male (id?).
Female.
Female, abdominal markings.
Female.
Female.
Female, abdominal markings.
Ero cambridgei Kulczynski, 1911
Description: Very similar to E. furcata. The ground colour of the abdomen is the same as the light parts of the carapace. However, most parts are mottled with whitish, reddish-brown and blackish brown spots. The whitish spots form a reticular pattern. Abdomen has one pair of rather small tubercles. Sternum is brown with an arrow-shaped marking in midline. Size: Female 3.2-3.6 mm; male 2.5-2.8 mm. Maturity: Females all year, males in autumn and spring. Habitat: Low vegetation of various habitats. Perhaps found in slightly more humid conditions than E. furcata but quite often the two species are found together. Range: Austria, Belgium, Czech Republic, Denmark, Finland, France (Mainland), Germany, Great Britain (Mainland), Great Britain (Northern Ireland), Greece (Dodecanese Islands), Greece (Mainland), Hungary, Ireland, Italy (Mainland), Latvia, Netherlands, Poland, Russia (Central European), Russia (Eastern European), Russia (Northern European), Russia (NW. European), Slovakia, Spain (Canary Islands), Sweden, Switzerland (van Helsdingen 2009.1). Global range: Palearctic (Platnick 10.0).
Male.
Male.
Male.
Ero furcata (Villers, 1789)
Description: Very similar to E. cambridgeiin overall appearance, including abdominal markings. However, the area in front of the anterior tubercles is often darker in this species. Abdomen has one pair of rather small tubercles. Sternum is brown with a lighter marking in midline that branch off to sides at rear. Size: Female 3.0-3.4 mm; male 2.4-2.6 mm. Maturity: Females all year, males in summer and autumn. Habitat: Low vegetation of various habitats. Perhaps found in slightly drier conditions than E. cambridgei but quite often the two species are found together. Range: Austria, Belarus, Belgium, Bosnia/Herzegowina, Bulgaria, Croatia, Czech Republic, Denmark, Estonia, Finland, France (Corsica), France (Mainland), Germany, Great Britain (Channel Islands), Great Britain (Mainland), Great Britain (Northern Ireland), Greece (Mainland), Hungary, Ireland, Italy (Mainland), Latvia, Liechtenstein, Lithuania, Moldova, Netherlands, Norway (Mainland), Poland, Portugal (Azores), Portugal (Mainland), Romania, Russia (Central European), Russia (Eastern European), Russia (Kaliningrad Region), Russia (Northern European), Russia (NW. European), Slovakia, Slovenia, Spain (Canary Islands), Spain (Mainland), Sweden, Switzerland, Ukraine, Yugoslavia (van Helsdingen 2009.1). Global range: Palearctic (Platnick 10.0).
Female.
Female.
Female.
Female.
Female.
Female.
Female.
Female abdominal markings.
Female.
Female abdominal markings.
Female.
Female.
Eggsack backlighted, showing content of three eggs.
Eggsack.
Subadult female.
Subadult female.
Subadult female, abdominal markings.
Ero tuberculata (De Geer, 1778)
Range: Austria, Belgium, Bulgaria, Croatia, Czech Republic, Denmark, Estonia, Finland, France (Corsica), France (Mainland), Germany, Great Britain (Mainland), Greece (Dodecanese Islands), Hungary, Italy (Mainland), Liechtenstein, Netherlands, Poland, Portugal (Madeira), Portugal (Mainland), Romania, Russia (Central European), Russia (Eastern European), Slovakia, Slovenia, Spain (Balearic Islands), Spain (Canary Islands), Spain (Mainland), Switzerland, Ukraine, Yugoslavia (van Helsdingen 2009.1). Global range: Palearctic (Platnick 10.0).
Female.
Female.
Female.
Female.
Female.
Female.
Female.
Female.
Female.
Female, metatarsus I with curved spines characteristic of the genus.
Female.
Eggsack.
Eggsack, backlighted showing content of ca. 8 eggs.
Female, abdominal markings.
Female, abdominal markings.
Female.
Female venter.
Female venter.