Porrhomma, Simon, 1884

Růžička, Vlastimil, 2018, A review of the spider genus Porrhomma (Araneae, Linyphiidae), Zootaxa 4481 (1), pp. 1-75 : 33-35

Porrhomma magnum Tanasevitch, 2012

Figs. 27A–F .

Porrhomma magnum Tanasevitch, 2012 — Tanasevitch (2012): p. 369, Figs. 1–14 , 23 , 24 (descr. ♂ ♀).

Material examined. Paratypes, 1 Ƌ 3 ♀, RUSSIA: Krasnoyarsk Area, West Sayan Mts., 30–40 km S of Aradan Village, Oyskiy Mt. Ridge , 1700 m a.s.l., 8 Jul 1993, leg. D. Logunov ( ZMMU, Ta-7684).

Diagnosis. Among four species of the magnum -group, P. magnum and P. longjiangense have developed eyes with black rings around. P. magnum can be distinguished from P. longjiangense by very small eyes ( Fig. 27A ) and Fe III–IV with one dorsal spine.

Description. ♀ (paratype from West Sayan Mts., Russia, 8 Jul 1993). Carapace yellow-brown, 1.02 mm wide, eyes very small, PME–PME = 2.4 ( Fig. 27A ). Abdomen greyish-yellow. Fe I–IV with one dorsal spine, Fe I with two prolateral spines. Ti I with one prolateral spine, Ti I–II with one retrolateral spine. Tm Mt I = 0.39, Mt I/CW = 1.16.

Epigynum with lateral wings ( Fig. 27C ). Copulatory ducts are very long, the most complicated in the genus, spermathecae are situated between ascending and descending parts of copulatory ducts ( Figs. 27D–F ).

Ƌ (together with female). The AP is shorter than wide, with a concave upper edge, the space between AP and PA very narrow. Embolus very long with a broad velum. Velum without a pigmented spot ( Fig. 27B ).

Variation. Ƌ ♀. Carapace 1.00– 1.35 mm wide. Tm Mt I = 0.34–0.39, Mt I/CW = 1.11–1.35 (n = 4).

Ecology. Recorded in mountainous tundra.

Global distribution. Mountains of southern Siberia , Russia and Kazakhstan after Tanasevitch (2012). See Fig. 28 .

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 23. A–F, Porrhomma errans from Chrast, Czechia. A, ♀ carapace, frontal view. B, embolic section. C, epigynum. D– F, vulva, ventral, caudal and dorsal. Scale bars, 0.1 mm.

FIGURE 24. Global distribution of Porrhomma errans.

FIGURE 27. A–F, Porrhomma magnum from West Sayan Mts., Russia. 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; MS, main sack; V, velum. Scale bars, 0.1 mm.

FIGURE 28. Global distribution of Porrhomma magnum.