A review of the spider genus Porrhomma (Araneae, Linyphiidae) Author Růžička, Vlastimil text Zootaxa 2018 2018-09-14 4481 1 1 75 journal article 29177 10.11646/zootaxa.4481.1.1 ac892ad5-037a-4486-9fdb-3082b98cbf49 1175-5326 1454736 BFC4982D-BB84-4141-BDFD-203F23CD1585 Porrhomma nekolai new species Figs. 38A–F , 39 . Male holotype , RUSSIA : Chukotka Autonomous Okrug, Christ Bay, env. of Egvekinot Town , SE slope, under stones, 15 Jul 1988 , leg. Yu. M. Marusik ( ZMMU ) . Paratypes : 1 ♀ , with same data as for holotype ; 1 ♂ 3 ♀ , Egvekinot Town , S slope, stony habitats in mountain tundra, 15 Jul 1988 , leg. Yu. M. Marusik ; 1 ♀ , Chukotka Autonomous Okrug, Amguema River, 67°03'N , 178°58'W , stony habitats, 22 Jul 1988 , leg. Yu. M . Marusik ; 1 ♂ 1 ♀ , Magadan Area , Duchka River , env. of Magadan , 13 Sep 1986 , leg. Yu. M. Marusik ( ZMMU ) . ♀ , CANADA : Yukon Territory , Kluane Lake , Cultus Bay , 61°11'N , 138°20'W , 1650 m a.s.l. , 10–23 Jul 1993 , leg. Yu. M. Marusik ( CNC ) . Ƌ, USA, Iowa , Delaware County, Elk River East , ca 7 km WSW of Colesburg , 42.6284°N , 91.9209°W , 13 July 1998 , leg. V. Růžička ( NMP , No. P 6A 6384). Ƌ, USA , Iowa , Delaware County , Backbone Cave , July , 45 yds from end, u. wood ( AMNH ) . FIGURE 36. A–F, Porrhomma montanum from Lanžhot, Czechia. A, ♀ carapace, frontal view. B, embolic section. C, epigynum. D–F, vulva, ventral, caudal and dorsal. Scale bars, 0.1 mm. FIGURE 37. Global distribution of Porrhomma montanum . Etymology. The species is named after Jeffrey C. Nekola (University of New Mexico , Albuquerque, USA ). Diagnosis. A large group of species is characterised by embolus of middle length and S-shaped ascending parts of copulatory ducts: P. borgesi , P. cambridgei , P. convexum , P. errans , P. nekolai , P. oblitum , P. pygmaeum and P. rosenhaueri . P. nekolai new species can be distinguished from all these species by the following combination of characters: large species (CW> 0.70), eyes reduced (PME–PME 1.7–2.0), legs very long (Mt I/CW> 1.3). Description. Male holotype (from Chukotka , Christ Bay, Egvekinot Town, 15 Jul 1988 ). Carapace yellowbrown, 1.10 mm long, 0.77 mm wide, eyes reduced, PME–PME = 1.7 ( Fig. 38A ). Abdomen greyish-yellow. Fe I with one dorsal and one prolateral spine. Ti I with one prolateral spine, Ti I–II with one retrolateral spine. Mt I/CW = 1.43.

Fe	Pt	Ti	Mt	Ta	Tm Mt
I	1.24	0.30	1.12	1.10	0.77	0.57
II	1.17	0.29	1.00	0.98	0.66	0.56
III	0.98	0.23	0.81	0.83	0.53	0.45
IV	1.21	0.28	1.17	1.11	0.68	–

Embolus of middle length with a narrow velum. AP has the form of a bird head, it is slender, narrowed ( Fig. 38B ). Male paratype (from Iowa, Delaware County, Elk River East , 13 July 1998 ): A palp ( Fig. 39 ). Female paratype (together with holotype ): carapace 0.78 mm wide, PME–PME = 1.8, Tm Mt I = 0.60, Mt I/ CW = 1.31. Ascending parts of the ducts are S-shaped. Spermathecae are formed behind the ascending part of the ducts ( Figs. 38C–F ). Variation. Ƌ ♀ . Carapace 0.71–0.78 mm wide, PME–PME = 1.6–2.0, Tm Mt I = 0.58–0.61, Mt I/CW = 1.31– 1.47 (N = 4). Comments. I recorded my first male under stones in Iowa , in 1998. I was accompanied by Jeffrey C. Nekola, an author of the concept of algific talus slopes as palaeorefugia ( Nekola 1999 ). In collections of the AMNH, I found the second male, collected in a cave, also in Iowa . Later, I obtained the material from Yukon Territory and Chukotka Peninsula, collected by Yuri M. Marusik during the research of spiders in stony habitats ( Marusik 2004 ). I decided to choose a complete pair from Chukotka for the description. Ecology. Specimens from Chukotka and Yukon Territory were collected in stony habitats. In Iowa , one male was collected in algific talus slope developed in limestone and one in a cave. It is in coincidence with the knowledge that lithobiontic species colonise more cold habitats (such as freezing scree slopes and caves) in warmer parts of their distribution area ( Růžička 1990 , 2011 ; Růžička et al. 2012 ). Global distribution. North-East Asia; Nearctic: from Yukon Territory to Iowa . See Fig. 40 .