Porrhomma cavernicola ( Keyserling, 1886 )

Růžička, Vlastimil, 2018, A review of the spider genus Porrhomma (Araneae, Linyphiidae), Zootaxa 4481 (1), pp. 1-75 : 22-24

Porrhomma cavernicola ( Keyserling, 1886)

Figs. 17A–F .

Linyphia incerta Emerton, 1875 — Emerton (1875): p. 280, Plate I, Figs. 13–21 (descr. ♂ ♀); preoccupied, replaced by Roewer (1942); examined by Miller (2005).

Willibaldia cavernicola Keyserling, 1886 — Keyserling (1886): p. 123, Tab. XV, Fig. 204 (descr. ♀); transferred by Roewer (1942); examined by Miller (2005).

Troglohyphantes cavernicolus — Crosby (1905): p. 368, Figs. 20–22 (descr. ♂); examined by Miller (2005).

Porrhomma incertum — Berland (1931): p. 384.

P. cavernicola — Roewer (1942): p. 603.

P. emertoni Roewer, 1942 — Roewer (1942): p. 603; replacement name for Linyphia incerta ; synonymised by Miller (2005).

P. cavernicola — Miller (2005): p. 428, Figs. 1–26 (redescr. ♂ ♀); synonymy.

Material examined. USA: Alabama, Limestone County, Spence Cave , 19 Aug 1965, 1 Ƌ 1 ♀, leg. S. Peck . Arkansas, Washington County, Devil’s Den State Park, Devil’s Den Cave , 28–31 May 1979, 4 Ƌ 7 ♀, leg. S. & J. Peck . Georgia, Bartow County, Kingston Saltpeter Cave , 13 Jul 1967, 1 Ƌ 3 ♀, leg. J.R. Holsinger, S. Peck, A. Fiske & R. Baroody . Illinois, Jo Daviess County, Angoma Farm Cave , 14 Nov 1965, 5 ♀, leg. S. Peck . Indiana, Lawrence County, Spring Mill State Park, Donaldson Cave , 10 Nov 1934, 2 ♀, leg. D.C. Lowrie. Orange County, Elrod Cave , 8 Aug 1964, 1 Ƌ, leg. T.C. Barr & S. Peck . Iowa, Jaskson County, Maquoketa Caves State Park, Barrea Cave , 1 Nov 1965, leg. S. Peck . Maryland, Washington County, Snively Cave, 4 Apr 1971, 2 Ƌ 1 ♀, leg. A. Norden. Misssouri, Stone County , Marvel Cave , 2 Apr 1959, 1 Ƌ 1 ♀, leg. T.C. Barr . Tennessee, Hawkins County, Sensabaugh Saltpeter Cave , 15 Apr 1967, 2 Ƌ 1 ♀, leg. J.R . Holsinger. Virginia, Augusta County, Madison Cave , 23 Aug 1958, 1 ♀, leg. T.C. Barr ; Gilea County, Clover Hollow Cave , 27 Jan 1962, 2 ♀, leg. J.R. Holsinger ; Tazewell County, Gully Cave (4 mi. SE Pounding Hill), 24 Jul 1974, 4 ♀, leg. J.R. Holsinger & D.C . Culver. West Virginia, Greenbrier County, Branford Cave , 10 Aug 1958, 1 ♀, leg. T.C. Barr ( AMNH) .

Diagnosis. The troglomorphic features—depigmentation, reduced eyes ( Fig. 17A ), and elongated legs (Mt I/ CW = 1.46)—separate this species from the other species occurring in North America ( P. convexum , P. terrestre , and P. nekolai ). Males of P. cavernicola ( Fig. 17B ) and P. microcavense are easily identified by the sickle-shaped and extremely thick AP. P. cavernicola is native in North America, P. microcavense in Europe.

Description. ♀ (from Devil’s Den Cave, Arkansas, U.S.A., 28–31 May 1979). Carapace yellow-brown, 0.79 mm wide, PME–PME = 6 ( Fig. 17A ). Abdomen greyish-yellow. Fe I–II with one or two dorsal spines, Fe I with one or two prolateral spines. Ti I with one prolateral spine, Ti I–II with one retrolateral spine. Tm Mt I = 0.48, Mt I/CW = 1.46.

Epigynum with translucent ducts and spermathecae ( Fig. 17C ). Ascending parts of the ducts are curved twice. Ducts reach deep into the abdomen ( Figs. 17D–F ).

Ƌ (together with female). Embolus of middle length with a narrow velum. The sickle-shaped AP is extremely thick ( Fig. 17B ).

Ecology. Exclusively in caves.

Global distribution. North America after Miller (2005) and this article. See Fig. 18 .

Figures

FIGURE 1. Porrhomma cambridgei from Jenišovice-Zalažany, Mravín, Czechia. Female habitus. Scale bar, 0.1 mm.

FIGURE 2. A–B, Porrhomma pygmaeum, male palp. A, retrolateral view. B, prolateral view. Abbreviations: AP, anterior process of the embolic plate; DSA, distal suprategular apophysis; E, embolus; EM, embolic membrane; EP, embolic plate; PA, posterior apex of the embolic plate; PT-OP, protegulum, outer process; PT-IM, protegulum, inner membrane; ST, subtegulum; T, tegulum. Scale bar, 50 µm.

FIGURE 3. A–B, Porrhomma microphthalmum, male palp. A, retrolateral view. B, prolateral view. Abbreviations as in Fig. 2. V, velum. Scale bar, 50 µm.

FIGURE 4. Porrhomma microps. Female vulva coloured by chlorazol black, dorsal view. Abbreviations: A, appendix; MS, main sack; SL, side loop of the copulatory duct. Scale bar, 0.1 mm.

FIGURE 5. A–C, female vulva, lateral view. A, Porrhomma pygmaeum. B, Porrhomma microcavense. C, Porrhomma microps. Scale bars, 0.1 mm.

FIGURE 6. A–F, Porrhomma altaica new species from Altai Mts., Azutau Ridge. A, ♂ carapace, frontal view. B, embolic section. C, epigynum. D–F, vulva, ventral, caudal and dorsal. Abbreviations: A, appendix; AP, anterior process of the embolic plate; E, embolus; MS, main sack; PA, posterior apex of the embolic plate; V, velum. Scale bars, 0.1 mm.

FIGURE 7. Porrhomma altaica new species from Altai Mts., Gor’ky Belok Mt. Ridge, male palp. Scale bar, 0.1 mm.

FIGURE 8. Global distribution of Porrhomma altaica new species.

FIGURE 13. A–F, Porrhomma cambridgei from Horka nad Moravou, Czechia; except B, Jenišovice-Zalažany, Mravín, Czechia. A, ♀ carapace, frontal view. B, embolic section. C, epigynum. D–F, vulva, ventral, caudal and dorsal. Scale bars, 0.1 mm.

FIGURE 14. Global distribution of Porrhomma cambridgei.

FIGURE 15. A–F, Porrhomma campbelli from Stožec-Dobrá, Czechia; except B, Harrachov, Czechia. A, ♀ carapace, frontal view. B, embolic section. C, epigynum. D–F, vulva, ventral, caudal and dorsal. Scale bars, 0.1 mm.

FIGURE 16. Global distribution of Porrhomma campbelli.

FIGURE 17. A–F, Porrhomma cavernicola from Devil’s Den Cave, Arkansas. A, ♀ carapace, frontal view. B, embolic section. C, epigynum. D–F, vulva, ventral, caudal and dorsal. Scale bars, 0.1 mm.

FIGURE 18. Global distribution of Porrhomma cavernicola.

FIGURE 19. A–F, Porrhomma convexum from Teplice nad Bečvou, Czechia; except B, Pec pod Sněžkou, Czechia. A, ♀ carapace, frontal view. B, embolic section. C, epigynum. D–F, vulva, ventral, caudal and dorsal. Scale bars, 0.1 mm.

FIGURE 20. Global distribution of Porrhomma convexum.

FIGURE 21. A–F, Porrhomma egeria from Sloup, Czechia. A, ♀ carapace, frontal view. B, embolic section. C, epigynum. D– F, vulva, ventral, caudal and dorsal. Scale bars, 0.1 mm.

FIGURE 22. Global distribution of Porrhomma egeria.