THERIDIIDAE SUNDEVALL, 1833

Agnarsson, Ingi, 2004, Morphological phylogeny of cobweb spiders and their relatives (Araneae, Araneoidea, Theridiidae), Zoological Journal of the Linnean Society 141 (4), pp. 447-626 : 465

THERIDIIDAE SUNDEVALL, 1833 : CLADE 53

The monophyly of Theridiidae receives strong support in this study. Unambiguous synapomorphies on this cladogram include: male palpal tibia distally broadened (14, Fig. 4E ), paracymbium lost (29, Fig. 92A- M ), bulb-cymbium lock mechanism (31, Fig. 31F ), alveolus flush on mesial cymbial margin (41, Fig. 92D–I, M ), MA containing loop of sperm duct (72, Figs 90F , 91A ), MA, tegulum membrane (73), a distal hood on MA (78, Fig. 31F ), retromarginal cheliceral teeth lost (110, Fig. 5F , several reversals), abdominal suprapedicellate apodemes weakly sclerotized and fairly smooth (165, Figs 4F , 63H , 82E, F ), highly flattened anterior PLS AG spigots (215, Figs 11B , 78B ), PMS mAP nubbins lost (220, Figs 18F, G , 25C, D ), exactly two PMS AC spigots (222, Fig. 18G ). Notable ambiguous synapomorphies are a nonrebordered labium (134, Fig. 5A , DELTRAN, also in Synotaxus ), and highly flattened posterior PLS AG spigots (216, ACCTRAN, not in Dipoena ).

Figures

Figure 4. Dipoena nigra, male. A–D, palp. A, mesial. B, ventral. C, ectal. D, ventral close; the scaly texture of the tegulum is unique to this species among the taxa explored here. E, apical view of tibia and base of palpus; note broad tibial tip (14-1), compared to the extremely narrow base which connects to the much broader patella (arrow). F, area above pedicel on abdomen. G, epiandrous gland spigots. Scale bars: A–F, 50 Mm; G, 20 Mm.

Figure 5. Dipoena nigra. A, female labium; the triangular shape is a synapomorphy of Hadrotarsinae (136-1). B, tip of male chelicera; note plumate hairs (121-1). C, D, male prosoma. C, front view, the short cheliceral paturon (arrow) is a synapomorphy of Hadrotarsinae (117-1). D, side view of the elevated prosoma (124-1). E, female prosoma side view, less elevated than in male; note also the short and thick segments of the palp. F, female cheliceral fang, both promargin (106-1) and retromargin (110-1) without teeth. G, tip of male fourth tarsus. Scale bars: A, B, 50 Mm; C–E, 100 Mm; F, G, 10 Mm.

Figure 11. Achaearanea tepidariorum. A, male SPR and nubbins. B, female PLS. C, D, female palpal claw, showing semi palmate condition (177-2). E, F, female fourth tarsus. E, theridiid tarsal comb (193-1). F, individual setae of the tarsal comb with longitudinal grooves (194-1), and hooked comb condition (195-1). Scale bars: A, E, F, 100 mm; B, C, 50 mm; D, 10 mm.

Figure 18. Anelosimus eximius. A, tip of cymbium of the expanded palp; note depressed tip (arrow), the light sclerotization of the cymbial tip is a synapomorphy of Anelosimus (26-1). B, male SPR; curvy rows (159-1) are characteristic of some Anelosimus. C, the much less pronounced female picks. D, male SPR area; note also proprioreceptic setae (PR, left arrow points toward a dorsal (11 o’clock) proprioreceptor, 163-1). E, female spinnerets. F, female PLS and PMS. G, male PMS. Scale bars: A–D, 50 Mm; E–G, 20 Mm.

Figure 25. Anelosimus studiosus, female. A, spinnerets. B, ALS. C, PLS. D, PMS. E, colular setae (arrow); note absence of colulus (172-1). F, cheliceral teeth. Scale bars: A, E, F, 100 Mm; B–D, 20 Mm.

Figure 31. Argyrodes, male palps. A–F, A. argyrodes. A, mesial. B, ventral. C, ectal. D, embolic division; note complex interactions of C, embolus. E, close look at the embolus and C. F, the BC-lock system; a hood on the MA tip (78-1) fits the hook on the cymbium (33-0). G, A. elevatus tibia; note trichobothria. two retrolateral (vertical arrows, 18-1) and a single prolateral (horizontal arrow, 19-1). Scale bars: A–C, 100 mm; D–G, 50 mm.

Figure 63. Phoroncidia sp. A–C, female. A, epigynum. B, spinnerets; note sclerotized ring around them (202-1). C, close-up of spinnerets. D-H, male. D, spinnerets. E, fourth tarsus. F, leg I; short and sturdy legs are typical for the genus. G, colular setae. H, abdominal apodeme. I, tip of female palpal tarsus, claw absent (176-1). Scale bars: A, 20 Mm. B, F, 100 Mm. C, D, 10 Mm. E, G-I, 50 Mm.

Figure 78. Theridion longipedatum. A–D, spinnerets. A, all. B, PMS. C, ALS; note unusual presence of two major ampullate spigots (MAP), no doubt teratological, as other specimens inspected had a single MAP, see e.g. D. D, male left field, arrows indicate AG scars (nonfunctional triplet, 219-0). E, female fourth tarsal comb. F, cheliceral promarginal teeth (arrows, 106-1). G, anterior part of male prosoma; note basal protrusions on chelicera (arrow, 115-1), a feature of many Theridion spp. and also, e.g. Coleosoma. Scale bars: A, D, G, 100 Mm. B, C, E, 20 Mm. F, 50 Mm.

Figure 82. Theridula opulenta. A, epiandrous gland spigots. B-F, female. B, epigynum. C, spinnerets. D, PLS and PMS. E, area around pedicel on abdomen. F, abdomen surface; note abundance of sclerotized depressions, possibly apodemes (arrows). Scale bars: A, B, D, 20 Mm. C, F, 50 Mm. E, 100 Mm.

Figure 90. Theridiid palps. A, Anelosimus sp. nov. (Tanzania). B, ditto, sperm duct trajectory. C, Anelosimus vittatus. D, ditto, sperm duct trajectory. E, indicating loops of A. vittatus sperm duct trajectory. F, G, Episinus angulatus (Blackwall) (redrawn from Knoflach, 1993). H, Carniella schwendingeri Knoflach (redrawn from Knoflach, 1996). Trichobothria omitted in F–H.

Figure 91. Schematic illustrations of theridiid palps. A, Argyrodes argyrodes (redrawn from Saaristo, 1978). B, ditto. C, Anelosimus eximius. D, A. eximius expanded palp. E, Theridion pictum (redrawn from Levi & Levi, 1962). F, T. pictum, expanded palp. G, Enoplognatha gemina Bosmans & Van Keer [redrawn from Levy, 1998, sub E. mandibularis (Lucas)]. H, Coleosoma floridanum, expanded palp, ventral. I, ditto, dorsal. Trichobothria omitted in A, D and E.

Figure 92. Schematic illustrations of palpal cymbia. A, Argiope argentata. B, Tetragnatha extensa. C, Nesticus reclusus. D, Steatoda americana. E, Argyrodes argyrodes. F, Anelosimus studiosus. G, Thymoites sp. H, Anelosimus vittatus. I, Ameridion nr. petrum. J, Euryopis sp. K, Thwaitesia sp. L, Selkirkiella alboguttata. M, Spintharus flavidus. Note that trichobothria are omitted in G, H and M.