The spider families of Britain and Ireland

L. Watson and M.J. Dallwitz

Linyphiidae

Including Microphantidae (= Erigoninae)

Money Spiders.

Morphology. The adult spiders 1.5–3.5 mm long (Erigoninae), or 1.2–6(–7.2) mm long (Linyphiinae); decidedly short-legged (rarely), or with legs of medium length to decidedly long-legged (the Erigoninae being generally relatively short-legged, the Linyphiinae relatively long- and slender-legged, but the legs rarely more than three times the body length). The caput conspicuously lobed, turreted, or with globular swellings (in the males of some Erigoninae, sometimes spectacularly so, e.g. in Walckenaeria spp.), or not conspicuously ornamented with lobes, turrets or globular swellings. The adult spiders with eight eyes. The eyes basically in two horizontal rows of 4 (but in some Erigoninae the pattern is disturbed in that some of the eyes are elevated on lobes. This is spectacularly exemplified in males of Walckenaeria acuminata, where the the caput exhibits a slender elongation bearing the two pairs of medians on its tip, and the laterals on its slightly thickened mid-region); all clear and glassy. The maxillae variable in form, about as long as broad to shorter than broad. The palpal organs of the male of complex structure and enclosed by the specialized, hollowed tarsal segment (the cymbium). The male palps with a well developed paracymbium. The female palps with a claw (in Linyphiinae), or without a claw. Metatarsus IV of the females without a calamistrum. Tarsal claws 3. Tarsus IV without a ventral ‘comb’. The abdomen conspicuously patterned dorsally (in most Linyphiinae), or plain dorsally (in most Erigoninae). The abdomen of the females without a cribellum. The reproductive openings of the females associated with an epigyne.

The adults making snare-webs (conspicuously so in many Linyphiinae), or not making snare-webs (many Erigoninae seeming to be ground-running predators; numerous species of Linyphiidae are highly dispersive, being generally encountered wandering or ballooning rather than in webs); the web-formers constructing horizontal sheet webs (on the ground or in vegetation, those of Linyphiinae often large, but those of Erigoninae often small and perhaps not genuine snares).

Representation in Britain and Ireland. About 270 species in Britain; in about 105 genera, e.g. Centromerus, Entelecara, Erigone, Lepthyphantes, Linyphia, Oedothorax, Porrhomma, Walckenaeria. The traditional tribes (Erigoninae, with about 58 genera) and Linyphiinae (about 46 genera), appear to reflect general morphological and behavioural trends, but have fallen into disfavour in recent times.

Comments. The labium is swollen distally, and the male palp bears a discrete chitinized paracymbium, which is variable in form and attached to the cymbium by a membrane. The chelicerae usually bear stridulating ridges, but have no lateral condyle, and their posterior margins exhibit one or more teeth. This family provides most of the ballooning species, and is responsible for adorning large areas of countryside with shimmering silken mantles.

Illustrations. • Labula, Lepthyphantes, Linyphia, Microlinyphia, Neriene. 139, Neriene radiata (Clerck): a, female; b, male; c, palpus of the male. 140, Neriene montana, or deGeer: a, female; b, male; c, palpus of the male. 141, Linyphia hortensis Sundevall: a, female; b, male; c, palpus of the male. 142, Microlinyphia pusilla (Sundevall), being Blackwall's Linyphia fuliginea: a, female; b, a variety of the female; c, male; d, palpus of the male. 143, Neriene peltata (Wider), this being Bristowe's assignment of Linyphia rubea Bl.: a, female; b, male; c, palpus of the male. 144, Lepthyphantes minutus (Bl.): a, female; b, male; c, palpus of the male. 145, Labulla thoracica (Wider), this being Linyphia cauta Bl.: a, female; b, male; c, palpus of the male. From Blackwall (1864). • Linyphia triangularis. Linyphia triangularis (Clerck): a, female; b, male; c, eyes; d, maxillae and labium; e, chelicera of the male; f, palpus of the male. From Blackwall (1864). • Neriene peltata and N. clathrata. 161, Neriene peltata (Wider)?: female. This being Blackwall's illustration of L. albula (Camb.), which Bristowe assigned to Linyphia peltata. 167, Neriene clathrata (Sund.), being Neriene marginata Bl.: a, female; b, male; c, palpus of the male; A, front view of the cephalothorax and chelicerae, and under-side showing the chelicerae, maxillae and labium. From Blackwall (1864). • Megalepthyphantes nebulosus, Lepthyphantes tenuis, and L. zimmermanni. 146, Megalepthyphantes nebulosus (Sund.): a, female; b, male; c, palpus of the male. 152, Lepthyphantes tenuis (Bl.): a, female; b, male; c; palpus of the male. 153, Lepthyphantes zimmermanni Bertkau: a, female; b, male; c, palpus of the male. From Blackwall (1864). • Lephthyphantes minutus and L. obscurus. 144, Lephthyphantes minutus (Bl.): a, female; b, male; c, the palpus of the male. 162, Lepthyphantes obscurus (Bl.): a, male; b, the palpus of the male. From Blackwall (1864). • Lephthyphantes alacris, L. ericaeus, and L. flavipes. 157, Lephthyphantes alacris (Bl.): a, female; b, male; c, the palpus of the male; d, a variety of the female. 159, Lepthyphantes ericaeus (Bl.): a, female; b, male; c, palpus of the male. 166, Lepthyphantes flavipes (Bl,): a, female; b, male; c, the palpus of the male. From Blackwall (1864). • Drapetisca socialis and Bolyphantes luteolus. 147, Drapetisca socialis (Sund.): a, female; b, male; c, palpus of the male. 149, Bolyphantes luteolus (Bl.): a, female; b, male; c, palpus of the male; d, the cephalothorax in profile. From Blackwall (1864). • Floronia bucculenta and Tapinopa longidens. 150, Tapinopa longidens (Wider): a, female; b, male; c, palpus of the male; d, the abdomen of the female, in profile. 151, Floronia bucculenta (Clerck): a, female; b, male; c, the palpus of the male; d, the abdomen of the female in profile. From Blackwall (1864). • Kaestneria pullata?. 164, Kaestneria pullata (Camb.)? This is Blackwall’s illustration of a female of Linyphia tenella Bl., as cautiously interpreted by Bristowe (the type lost). • Bathyphantes gracilis and B. nigrinus. 156, Bathyphantes nigrinus (Westr.): a, female; b, male; c, the palpus of the male (the illustrations representing Linyphia pulla Bl.). 163, Bathyphantes gracilis (Bl.): a, male; b, its palpus.165, B. gracilis (Bl.), another male and its palpus: the specimen figured representing L. circumspecta Bl., now reduced to synonymy. From Blackwall (1864). • Helophora insignis. 160, Helophora insignis (Bl.): a, female; b, male; c, palpus of the male; d, cephalothorax and abdomen in profile. From Blackwall (1864). • Centromerita bicolor. 168, Centromerita bicolor (Bl.): a, female; b, male; c, palpus of the male. From Blackwall (1864). • Porrhomma errans and Porrhomma pygmaeum. 170, Porrhomma errans (Bl.): a, the palpus of the male; b, male; c, female. 177, Porrhomma pygmaeum (Bl.): a, male; b, female; c, palpus of the male. From Blackwall (1864). • Microneta viaria and Meioneta rurestris. 171, Microneta viaria (Bl.): a, palpus of the male; b, male. 172, Meioneta rurestris (C.L. Koch): a, palpus of the male; b, female; c, male (this illustration representing Neriene gracilis Bl., reduced to synonymy). 178, Meioneta rurestris (C.L. Koch): a, male; b, female; c, palpus of the male (this representing N. flavipes Bl., reduced to synonymy). From Blackwall (1864). • Gnathonarium dentatum, Tiso vagans and Tmeticus affinis. 173, Tiso vagans(Bl.): a and b, two views of the palpus of the male; c, male; d, female. 174, Gnathonarium dentatum (Wid.): a, palpus of the male; b, front view of the cephalothorax and chelicerae; d, male. 175, Tmeticus affinis (Bl.): a, male; b, female; c, front view of the cephalothorax and chelicerae; d, the palpus of the male. From Blackwall (1864). • Hypomma bituberculatum and Hypomma cornutum. 181, Hypomma cornutum (Bl.): a, male; b, female; c, side view of the cephalothorax and chelicera; d, and e, two views of the palpus of the male. 182, Hypomma bituberculatum (Wid.): a, male; b, female; c, palpus of the male; d, side view of the cephalothorax and chelicera; e, front view of the cephalothorax and chelicerae. From Blackwall (1864). • Gongylidium rufipes. 180, Gongylidium rufipes (Sund.): a, female; b, male; c and d, two views of the palpus of the male. From Blackwall (1864 - his Neriene munda Bl.). • Gongylidiellum vivum?. 179, Gongylidiellum vivum (Camb.)?: male, and its palpus. From Blackwall (1864. His Neriene parva Bl., tentatively referred to G. vivum by Bristowe). • Leptorhoptrum robustum. 176, Leptorhoptrum robustum (Westr.): male and its palpus. From Blackwall (1864. Labelled by him Neriene huthwaiti Camb., which was referred by Bristowe to Phaulothrix huthwaiti, which is now listed under L. robustum.). • Oedothorax apicatus. 183, Oedothorax apicatus (Bl.): a, male; b, profile of the cephalothorax; c, the palpus of the male. From Blackwall (1864). • Oedothorax fuscus and Oedothorax agrestis. 189, Oedothorax fuscus (Bl.): a, male; b, female; c-e, three views of the palpus of the male. 190, Oedothorax agrestis (Bl.): a, male; b, female; c-e, three views of the palpus of the male From Blackwall (1864. See the next image for more details of the male palps). • Oedothorax fuscus cf. O. agrestis, male palps. D and E, Blackwall's (1864) drawings of the male palp of Oedothorax agrestis (Bl.) and Oedothorax fuscus (Bl.), respectively, showing undersides (a), outside profiles (b) and upper-sides (c). • Oedothorax gibbosus. 192, Oedothorax gibbosus (Bl.), male: a, cephalothorax and chelicera; b and c, two views of the palpus of the male. From Blackwall (1864; labelled by him tuberosus Bl., which is now regarded as a synonym of gibbosus Bl.). • Dicymbium nigrum. 185, Dicymbium nigrum (Bl.): a, male; b, female, c and d, two views of the palpus of the male; e, the cephalothorax in profile. From Blackwall (1864). • Gonatium rubellum and Gonatium rubens. 184, Gonatium rubens (Bl.): a, female; b, male; c, one of the first pair of legs of the male; d and e, two views of the male palpus. 194, Gonatium rubellum (Bl.): a, male; b and d, two views of the palpus of the male; c, female. From Blackwall (1864). • Hylyphantes graminicola and Sintula corniger. 186, Hylyphantes graminicola (Sund.): a, sede view of cephalothorax and chelicera; b, female; c, male; d and e, two views of the palpus of the male. 187, Sintula corniger (Bl.): a, male; b and c, two views of its palpus. (From Blackwall (1864). • Erigone atra or E. longipalpis?. Erigone atra Bl. or E. longipalpis (Sund.). 188a, male; 188b, female; 188c, front view of the cephalothorax and chelicerae; d and e, two views of the palpus of the male. Ca-Cc, the palpus of the male: upper-side (Ca), under-side (Cb) and outside profile (Cc). Blackwall (1864) labelled these illustrations Neriene longipalpis Sund., of which he regarded his own Erigone atra Bl. a synonym. Erigone atra Bl. and E. longipalpis (Sund.) are accepted as separate species by authorities subsequent to Bristowe, but it may be impossible to determine from these pictures which of them Blackwall actually drew. • Poeciloneta variegata. 195, Poeciloneta variegata Bl.: a, female; b, male; c, the palpus of the male. From Blackwall (1864, illustrated by him under the pseudonym Neriene variegata Bl.). • Macrargus rufus and Saaristoa abnormis. 200, Saaristoa abnormis (Bl.): a. male; b, the palpus of the male. 201, Macrargus rufus (Wid.): a, female; b, male; c, the palpus of the male. From Blackwall (1864, with M. rufus illustrated by him under the synonym Neriene rubripes Bl.). • Stemonyphantes lineatus. 193, Stemonyphantes lineatus (Linn.): a, male; b, female; c, the palpus of the male. From Blackwall (1864, labelled by him with the synonym Neriene trilineata Koch). • Walckenaeria acuminata. 203, Walckenaeria acuminata Bl.: a, male; b, female; c, front view of the male cephalothorax and chelicerae; d, side view of the male cephalothorax; e, side view of the cephalothorax of the female; f, chelicerae, maxillae, labium and sternum of the female; g, front view of the cephalothorax and chelicerae of the female; h and i, two views of the palpus of the male. From Blackwall (1864). • Walckenaeria cuspidata and Walckenaeria vigilax. 191, Walckenaeria vigilax (Bl.): a, male; b and c, two views of the palpus of the male. 204, Walckenaeria cuspidata Bl.: a, female; b, male; c, the palpus of the male; d, the male cephalothorax and chelicera in side view (showing the hair-tufted, cusp-like projection in front of the posterior median eyes). From Blackwall (1864). • Walckenaeria monoceros and Walckenaeria unicornis. 205, Walckenaeria monoceros (Wider): a, male; b, the male cephalothorax and chelicera in side view; c, the palpus of the male. 207, Walckenaeria unicornis Camb.: a, male; b, female; c, cephalothorax and chelicera of the male in side view; d, the palpus of the male; e, front view of the cephalothorax and chelicerae of the male (cf. c), showing the characteristic, apically bifurcated protuberance in front of the posterior median eyes. From Blackwall (1864). • Walckenaeria obtusa. 208, Walckenaeria obtusa Bl.: a, male; b, its cephalothorax and chelicera in side view; c and d, two views of the male palpus. From Blackwall (1864). • Leptothrix hardyi and Monocephalus fuscipes. 206, Leptothrix hardyi (Bl.): a, male; b, the palpus of the male; c, side view of the cephalothorax and chelicera. 209, Monocephalus fuscipes: a, male; b, side view of the cephalothorax and chelicera; c and d, two views of the palpus of the male. From Blackwall (1864). • Entelecara flavipes and Pelecopsis parallela. 211, Pelecopsis parallela (Wider): a, male; b, female; c, side view of the cephalothorax and abdomen; d, front view of cephalothorax, caput and chelicerae; e, the palpus of the male. 213, Entelecara flavipes (Bl.): a, male; b, female; c and d, two views of the palpus of the male; e and e', front and side views of the cephalothorax, caput and chelicerae. From Blackwall (1864). • Lophomma punctatum. 210, Lophomma punctatum (Bl.): a, female; b, male; c, side view of the cephalothorax and chelicera; d and e, two views of the palpus of the male. From Blackwall (1864). • Cnephalocotes obscurus. 212, Cnephalocotes obscurus (Bl.): a, male; b and d, two views of the palpus of the male; c, side view of the cephalothorax and chelicera. From Blackwall (1864). • Troxochrus scabriculus. 216, Troxochrus scabriculus (Westr.): a, male; b, female; c, side view of the cephalothorax; d, front view of the cephalothorax, caput and chelicerae; e and f, two views of the palpus of the male. From Blackwall (1864). • Erigonella hiemalis. 217, Erigonella hiemalis (Bl.): a, male; b, female; c and d, two side views of the cephalothorax, caput and chelicerae; e and f, two views of the palpus of the male. From Blackwall (1864). • Dismodicus bifrons. 218, Dismodicus bifrons (Bl.): a, male; b, female; c, the cephalothorax, caput and chelicerae in side view; d and e, two views of the palpus of the male. From Blackwall (1864). • Baryphyma pratense. 222, Baryphyma pratense (Bl.): a, male; b, female; c and d, two views of the palpus of the male; e, side view of the cephalothorax, caput and chelicerae. From Blackwall (1864). • Araeoncus humilis and Diplocephalus cristatus. 223, Araeoncus humilis (Bl.): a, male; b and b', the cephalothorax, caput and chelicerae, in side view and from the front, respectively; c and d, two views of the palpus of the male. 224, Diplocephalus cristatus (Bl.): a, male; b, side view of the cephalothorax, caput and chelicera; c and d, two views of the palpus of the male. From Blackwall (1864). • Diplocephalus picinus. 228. Diplocephalus picinus (Bl.): a, male; b, side view of the cephalothorax and chelicera; c and d, two views of the palpus of the male. From Blackwall (1864). • Ceratinella brevis. 221, Ceratinella brevis (Wider): a, male; b, female; c, side view of the abdomen, cephalothorax, caput, chelicera and maxilla; d and e, two views of the palpus of the male. From Blackwall (1864; this being his representation of Walckenaeria depressa Bl., which is now reduced to synonymy). • Pelecopsis nemoralis and Trichopterna thorelli. 229, Trichopterna thorelli (Westr.): a, male; b, side view of its cephalothorax and caput. 230, Pelecopsis nemoralis (Bl.): a, male; b, side view of its cephalothorax and caput; c and d, two views of the palpus of the male. From Blackwall (1864; with Fig. 229 representing Walckenaeria fastigata Bl., reduced to synonymy). • Peponocranium ludicrum. 231, Peponocranium ludicrum (Cambr.): a, female; b, male; c and d, two views of the palpus of the male; e and f, front and lateral views, respectively, of the cephalothorax, caput and chelicerae. From Blackwall (1864). • Savignya frontata. 232, Savignya frontata (Bl.): a, male; b and c, front and side views, respectively, of its cephalothorax, caput and chelicerae; d and e, two views of the palpus of the male. From Blackwall (1864). • Trichoncus saxicolus. 226. Trichoncus saxicolus (Camb.): a, male; b, female; c, d, and d’, three views of the palpus of the male; e, side view of the cephalothorax and chelicera. From Blackwall (1864). • Pocadicnemis pumila. 227, Pocadicnemis pumila (Bl.): a, male; b, side view of the cephalothorax and chelicera; c and d, two views of the palpus of the male. From Blackwall (1864).