Phyxelididae Lehtinen 1967
Creators: name: Griswold, Charles E.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Phyxelididae

description: Phyxelididae Lehtinen, 1967
Amaurobiidae Phyxelidinae Lehtinen, 1967: 328. Griswold, 1990. Elevated from subfamily of Amaurobiidae to family and placed as sister group of Titanoecidae by Griswold et al., 1999: 59. Discussion in Griswold et al., 2005: 35.
Diagnosis: Entelegyne, cribellate spiders with thorn-like setae located probasally on both the female and male palpal femora (Figs. 9, 53, 54), a calamistrum that originates medially on the female metatarsus IV (Figs. 8, 50), PMS paracribellar spigots that encircle the spinneret margin anteriorly and that are crowded together such that the bases are laterally flattened (Griswold et al., 2005, fig. 46C) and male metatarsus I modified with apparent clasping structures (Figs. 27, 28, 56–61).
Synapomophies: Synapomorphies for the family implied by the phylogenetic analysis of Griswold, Ramírez, Coddington and Platnick (2005) were thorn-like setae located probasally on both the female and male palpal femora, a calamistrum that originates medially on the female metatarsus IV, PMS paracribellar spigots that encircle the spinneret margin anteriorly and that are crowded together such that the bases are laterally flattened, and male metatarsus I modified with apparent clasping structures. In their analysis (Griswold et al., 2005), further synapomorphies united the tribes Phyxelidini and Vidoleini: a bilaterally divided chilum and branched median tracheae. Other potential synapomorphies uniting Phyxelidini and Vidoleini include epiandrous spigots separated into two bunches (Griswold et el., 2005, figs. 160A, B) and a conspicuous, enlarged, dark seta arising laterally from the tip of the PLS (Fig. 14). Vytfutia have an entire chilum (Fig. 4) and lack epiandrous spigots and also lack enlarged, dark seta arising laterally from the tip of the PLS (Figs. 12, 13).
Description: (Phyxelididae) Eight eyes in two nearly straight rows (Figs. 1-4, 26, 34), canoeshaped tapeta (Fig. 2), chilum entire (Vytfutiini, Fig. 4) or divided (Phyxelidini, Vidoleini); endite with apical serrula; sternum shield-shaped, posteriorly blunt to pointed (Figs. 21, 29, 32), labium free (Figs. 29, 33); tarsal trichobothria absent, with only a single, subapical trichobothrium on metatarsi, multiple dorsal trichobothria on tibiae, trichobothria with transverse ridges, tarsal organ capsulate with round orifice; setae plumose (Figs. 52, 53, 55), rarely (Malaika) also with feathery scales; palpal femora of both sexes with probasal thorns comprising enlarged setal bases and/or thickened setae (Figs. 9, 53, 54); femora to metatarsi of legs with spines (Figs. 10, 11) in most species (Vytfutia halandrefana sp. nov. have reduced spination); trochanters shorter than coxae (Figs. 21), trochanters unnotched or with very weak concavity (Figs. 5, 6), autospasy at coxa – trochanter joint; males of most species with metatarsus I modified (Figs. 27, 28, 56–61), median concavity typically retrolateral in African and Eurasian genera, but prolateral in Malagasy clade (Ambohima, Manampoka and Rahavavy), only leg I modified in most genera, legs I and II modified in Ambohima and Manampoka; leg tarsi with three claws, serrate accessory setae, claw tufts and scopulae absent (Figs. 52, 55); female palp with toothed claw (Fig. 9); metatarsi III and IV apical preening combs present (Vidoleini) or absent (Phyxelidini, Vytfutiini); calamistrum linear, originating near middle of metatarsus IV (Figs. 8, 50), calamistral setae with multiple rows of teeth or smooth (Fig. 51); lateral tracheae simple, medians simple (Vytfutiini, some Phyxelidini) or with few to many branches (Phyxelidini, Vidoleini); pedicel with lorum transversely divided (Fig. 7), epiandrous spigots grouped into two lateral bunches (Phyxelidini, Vidoleini) or absent (Vytfutiini); cribellum divided (Figs. 1213) with two fields of uniformly distributed strobilate cribellate spigots; spinnerets described in Griswold et al., 2005 (figs. 46-50) female ALS with one (Vytfutiini) or two (Phxelidini and Vidoliini) MAP spigots at the inner edge and field PI spigots with round base margins, these interspersed with tartipores; female PMS with numerous (12—30) PC spigots encircling anterior margin, PC spigot bases elongate, pressed together and flattened, each PC spigot surmounted by a single strobilate shaft, spigot cuticle ridged; one large mAP spigot with nubbin and tartipore posteriad to this, posteriorly several AC and one to four CY spigots; male PMS with PC spigots replaced by encircling row of nubbins, large median tartipore and nubbin that replaces mAP spigot; female PLS with domed apical segment, with stout, curved seta apicolaterally (Phxelidini and Vidoleini), absent from Vytfutiini; with apical MS spigot, MS flanking PC or AC spigots present or absent, field of several AC and 2 or more mesal CY spigots; males lack CY spigots, MS spigot replaced by large nubbin; anal tubercle small, simple, with slender setae (Fig. 13); male palpal tibia with dorsoapical process (D or DTA) (Figs. 16, 38, 47), sclerotized (Phyxelidini, Vytfutiini) or partly sclerotized and partly hyaline (Vidoleini), additional RTA present in Vytfutia (Figs. 17, 37, 46); cymbium without trichobothria or chemosensory scopulae; male palpal bulbs diverse, Vytfutiini and Phyxelidini with conductor (C) and median apophysis (MA), the latter lacking in Ambohima, Vidoleini with three to five conical tegular processes of dubious homology; female epigyna simple, without teeth, with median (ML) and lateral (LL) lobes separate or fused (Vytfutiini, Figs. 18, 23, 24, 39, 41, 48); vulva entelegyne, of various conformations, fertilization ducts (FD) located posterioriorly (Fig. 19); webs cribellate, may be substrate limited and radiate from retreat (Griswold et al., 2005, figs. 202 A, B, E, F), or form aerial sheets (Griswold, Wood and Carmichael, 2012, fig. 2 A), spiders walk on or hang beneath webs (Griswold, Wood and Carmichael, 2012, figs 2 B, 5), cribellate silk carding type II form (carding leg braced with mobile leg IV), at least Phyxelidini wrap prey after bite with slow alternating movements of legs IV; cribellate band (studied in Phyxelida) entire, cribellar fibrils cylindrical with nodules, axial fibers and reserve warp present (Griswold et al., 2005, figs. 121A–C).
description: Published as part of Griswold, Charles E., 2022, The Lace Web Spider Genus Vytfutia Deeleman-Reinhold (Araneae, Phyxelididae) in the Indo-Pacific Region, pp. 329-355 in Proceedings of the California Academy of Sciences 67 (14) on pages 331-332, DOI: 10.5281/zenodo.11513175