Mesabolivar iguazu Huber, 2000

Huber, Bernhard A., 2018, The South American spider genera Mesabolivar and Carapoia (Araneae, Pholcidae): new species and a framework for redrawing generic limits, Zootaxa 4395 (1), pp. 1-178 : 96-98

Mesabolivar iguazu Huber, 2000

Figs 382–383 , 408–410 , 437–438

Mesabolivar iguazu Huber, 2000: 215 ; figs 138, 830–839 (♂ ♀, Argentina, Brazil). Huber 2014: 139 (except specimens from Puerto Libertad and Arroyo Uruguay km 30; see M. chapeco ).

Diagnosis. (amendments; see Huber 2000). Distinguished from similar congeners ( M. uruguayensis , M. chapeco , M. yucuma ) by long proximal processes on male chelicerae (Huber 2000: fig. 834; similar in M. chapeco , where the distal apophyses are much less prominent in lateral view); also by male procursus ( Figs 408–410 ; distinctive distal sclerotized and membranous elements), and by shape of epigynum ( Figs 437–438 and Huber 2000: figs 837– 838; anterior plate with pair of processes and pocket at posterior margin; similar M. charrua and M. yucuma ).

Type material. ARGENTINA: Misiones: ♂ holotype, AMNH, Parque Nacional Iguazú [25.66°S, 54.47°W], 206 m a.s.l., palm forest, 8.xii.1990 – 6.i.1991 (S. & J. Peck).

New records. ARGENTINA: Misiones: 5♂ 18♀, MACN ( Ar 19974), Parque Nacional Iguazú, Área Cataratas [25°40.7’S, 54°26.9’W], 4.ix.1963 (collector not given) ; 7♂ 6♀, MACN ( Ar 4313), same locality, xi.1954 (Schiapelli, De Carlo) ; 1♂, MACN ( Ar 20052), same locality, 16.viii.1959 (Nuñez) ; 1♂ 1♀, MACN ( Ar 20016), same locality, 13.i.1966 (Galiano) ; 1♀, ZIMG (II-28332), same locality, 1.iii.2012 (G. Rubio) . 1♀, MACN ( Ar 20088), Parque Nacional Iguazú, Área Cataratas, Sendero Macuco, 15.vii.1993 (M. di Vitteti) ; 1♂, MACN ( Ar 20086), same locality, 8–15.ii.1995 (M.J. Ramirez) ; 1♂ 2♀, MACN ( Ar 22113–15), same locality, 18–21.i.2005 (C. Grismado et al.) . 1♂ 1♀, ZIMG (II-28333–34), same locality, 24.ii.2012 (P. Michalik) . 1♀ 2 juvs, MACN (Ar 4017), Parque Nacional Iguazú , x.1950 (Schiapelli, De Carlo) ; 4♂ 2♀, MACN ( Ar 20077), same locality, 8– 15.ii.1995 (M.J. Ramirez) ; 1♂, MACN ( Ar 20107), same locality, vii.1983 (P.A. Goloboff) ; 2♂ 2♀, MACN ( Ar 20079), same locality, vii.1985 (M. Ramirez) . 1♀, MACN (Ar 20096), Parque Nacional Iguazú, Palmital, 5 km W Yacuí [25°40’S, 54°12’W], 8–15.ii.1995 (M.J. Ramirez) . 1♀, MACN (separated from Ar 20049), Parque Nacional Iguazú, Ruta National 101 y Arroyo Yacuí [25°40.8’S, 54°10.1’W, 230 m], i.1966 (Galiano) . 1♂, ZIMG (28335), Parque Nacional Iguazú, “ Apepu ”, 29.ii.2012 (collector not given) . 1♂, MACN (separated from Ar 19971), Parque Provincial Cruce Caballero , NE San Pedro [~ 26.5°S, 54°W, 500 m], 27–29.x.1995 (M. Ramirez) . 1♂, MACN (Ar 20091), Parque Provincial Uruguaí [25°52’S, 54°34’W, 200 m], Refugio Caá-Porá, 3 km W Deseado , 14– 15.ii.1995 (M. Ramirez) . 1♂, MACN (Ar 4314), Departamento Frontera, San Antonio [26°03’S, 53°44’W, 530 m], Refugio Piñalitos , ix.1954 (Schiapelli, De Carlo) . 1♂, MACN ( Ar 4046), Departamento Frontera, Tobuna [26°28’S, 53°53’W, 580 m], ii.1952 (M. Partridge).

BRAZIL: Paraná: 29♂ 15♀, ZFMK (Ar 19181), Foz do Iguaçu National Park (25.63– 25.69°S, 54.43– 54.44°W), 200–230 m a.s.l., 31.x.2014 (B.A. Huber, L.S. Carvalho) ; 1♂ 2♀ 1 juv. in pure ethanol, ZFMK (Br 14- 205), same data . 17♂ 15♀ 3 juvs, ZFMK (Ar 19182–83), Foz do Iguaçu National Park, near Céu Azul (25.130°S, 53.823°W to 25.149°S, 53.807°W), 620–690 m a.s.l., 2.xi.2014 (B.A. Huber, L.S. Carvalho) ; 2♀ in pure ethanol, ZFMK (Br 14-208), same data .

Description (amendments; see Huber 2000). Tibia 1 in 65 newly examined males: 7.6–12.1 (mean 10.5). Femora 2 and 3 in some males clearly wider than other femora, in others barely wider (e.g., diameters of femora in small male: 0.19, 0.21, 0.21, 0.19; in large male: 0.30, 0.37, 0.35, 0.31). Legs densely covered with short hair, tibiae dorsally with single row of long hairs. Prolateral trichobothrium present on tibia 1. Proximal cheliceral processes vary slightly in diameter (even among specimens from a single collecting event) but are consistently long.

Females in general similar to males but all femora same diameter; tibia 1 in 50 females: 5.6–9.3 (mean 7.6). Epigynum humps vary slightly in shape (in lateral view), even within samples from a single collecting event.

Natural history. The spiders were found in domed webs close to the ground. When disturbed, they started swinging with large amplitude and ran back into the protective shelter.

Distribution. Known from several localities in the Iguazu Falls area ( Argentina, Brazil) ( Fig. 737 ).

Figures

FIGURES378–389. Live specimens,Mesabolivar iguazugroup.378–379.M.chapeco sp. n., male and female from Chapecó. 380–381. M. yucuma sp. n., male and female from Turvo. 382–383. M. iguazu Huber, 2000, males from Iguaçú. 384–385. M. charruaMachado etal., 2013, male andfemale from Serra Geral. 386–387.M.catarinensis sp. n., male and female from Serra Geral.388–389. M. bicuspis sp. n., male and female from St. Hilaire/Lange.

FIGURES408–418. Mesabolivar iguazuHuber, 2000(408–410, ZFMK Ar 19181) and M.argentinensis(Mello-Leitão, 1938) (411–418, MACN Ar 32453). 408–414. Left procursi, prolateral, dorsal, and retrolateral views (412: prolateral, slightly dorsal view). 415–416. Male chelicerae, frontal and lateral views. 417–418. Epigynum, ventral and lateral views. Scale lines: 0.2 (408–414; all procursi at same scale), 0.3 (415–416), 0.5 (417–418).

FIGURES 433–446. Female epigyna in ventral and lateral views and cleared female genitalia in dorsal views, Mesabolivar iguazu group. 433.M. chapeco sp. n. (ZFMK Ar 19175). 434–436. M.yucuma sp. n. (ZFMK Ar 19176). 437–438. M.iguazu Huber, 2000 (ZFMK Ar 19181). 439–440. M. charrua Machado et al., 2013 (ZFMK Ar 19184). 441–442. M. argentinensis (Mello-Leitão, 1938) (MACN Ar 20050). 443–445. M. catarinensis sp. n. (ZFMK Ar 19189). 446. M. bicuspis sp. n. (ZFMK Ar 19194).

FIGURES 736–737. Known distribution of the Mesabolivar iguazu group. TL, type locality. “?”: dubious northern records of M. uruguayensis in Machado et al. (2013) (cf. Huber 2015:60).