The South American spider genera Mesabolivar and Carapoia (Araneae, Pholcidae): new species and a framework for redrawing generic limits Huber, Bernhard A. Zootaxa 2018 2018-03-19 4395 1 1 178 3ZXC5 Huber, 2018 Huber 2018 [151,408,1151,1177] Arachnida Pholcidae Mesabolivar GBIF Animalia Araneae 9 10 Arthropoda species acrensis sp. nov.   Diagnosis.Males are easily distinguished from most known congeners by shape of procursus ( Fig. 14; distinctively widened and strongly curved distal element; very similar in  M. pseudoblechroscelis; compare Fig. 14with figs 5.07–08 in Machado 2011); from two most similar species (  M. pseudoblechroscelis,  M. maraba) also by bulbal process ( Fig. 15; shape of distal structures); from most species (except  M. pseudoblechroscelis,  M. maraba,  M. huambisa) also by armature of male chelicerae ( Figs 18–19; pair of slender apophyses, straight in lateral view), and by shape of epigynum ( Figs 20–21, 32–37; large median depression, lateral margins slightly diverging towards anterior, bordered posteriorly by large pocket; pair of conical lateral processes directed slightly towards posterior - epigynum possibly indistinguishable from  M. maraba,due to variation, see below); from  M. marabaand other putatively close relatives also by female internal genitalia ( Figs 22, 38; elongated pore-plates converging towards posterior) (female of  M. pseudoblechroscelisunknown).   Etymology.The specific name is an adjective derived from the typelocality.    Typematerial. BRAZIL:  Acre: ♂ holotype, 1♀ paratype, UFMG(21497–98), 2♂ 23♀ paratypes, ZFMK(Ar 18942–43), Rio Branco, Reserva Florestal Humaitá ( 9.749°S, 67.666°W), 180 ma.s.l., 28.x.2016(B.A. Huber, L.S. Carvalho).   Other material examined. BRAZIL:  Acre: 1 juv., together with paratypes;  1♀3 juvs in pure ethanol, ZFMK( Br16-309), same data as types.  2♂ 17♀, ZFMK( Ar18944), Rio Branco, Fazenda Experimental Catuaba( 10.08°S, 67.625°W),  225 ma.s.l.,  26–27.x.2016( B.A. Huber, L.S. Carvalho);  2♀in pure ethanol, ZFMK( Br16- 306), same data;  1♂ 8♀, ZFMK( Ar18945), Rio Branco, Fazenda Experimental Catuaba( 10.078°S, 67.619°W),  200 ma.s.l.,  29.x.2016( B.A. Huber, L.S. Carvalho).    Assignedtentatively. BRAZIL:  Acre: 3♂ 10♀2 juvs, ZFMK( Ar18946), Cruzeiro do Sul, forest near airport ( 7.596°S, 72.767°W),  200 ma.s.l.,  30.x.2016( B.A. Huber, L.S. Carvalho, E.O. Machado);  1♀ 1 juv.in pure ethanol, ZFMK( Br16-313), same data.    Amazonas: 3♂ 2♀, ZFMK (Ar 18947), Guajará, forest at Fazenda Colorado, ‘site 2’ ( 7.528°S, 72.655°W), 210–240 ma.s.l., 31.x.2016(B.A. Huber, L.S. Carvalho, E.O. Machado).  Description. Male( holotype) MEASUREMENTS. Total body length 2.3, carapace width 1.05. Distance PME-PME 120 µm, diameter PME 110 µm, distance PME-ALE 80 µm, distance AME-AME 30 µm, diameter AME 45 µm. Sternum width/length: 0.80/ 0.55. Leg 1: 30.1 (7.1 + 0.5 + 7.2 + 13.5 + 1.8), tibia 2: 4.7, tibia 3: 3.4, tibia 4: 5.0; tibia 1 L/d: 76. Femora 1–4 width (at half length): 0.14, 0.15, 0.15, 0.15. COLOR (in ethanol). Carapace ochre-yellow, with barely visible darker median mark, ocular area also slightly darkened; sternum orange; legs ochre to light brown, with indistinct darker rings on femora (subdistally) and tibiae (proximally; subdistal rings barely visible), tips of femora and tibiae lighter; abdomen greenish-gray, with dark internal marks dorsally and laterally, without ventral mark. BODY. Habitus as in Fig. 1; ocular area raised (higher than usual in genus); carapace with distinct median furrow; clypeus slightly swollen and whitish, with sclerotized margin; sternum unmodified. CHELICERAE. With pair of long, slender apophyses, straight in lateral view ( Figs 18–19).   FIGURES 13–17.  Mesabolivar acrensis  sp. n.(13–15, ZFMK Ar 18942) and  M. maraba  sp. n.(16–17, ZFMK Ar 18948). 13– 14. Left male palp, prolateral and retrolateral views. 15–16. Left bulbal processes, prolateral views (arrow points at distinctive sclerotized area). 17. Left procursus, retrolateral view. Abbreviations: b, genital bulb; bp, bulbal process; c, coxa; f, femur; p, procursus, ta, tarsus; ti, tibia; tr, trochanter. Scale lines: 0.5 (13–14, 17), 0.3 (15–16).   FIGURES 18–25.  Mesabolivar acrensis  sp. n.(18–22; ZFMK Ar 18942–43) and  M. maraba  sp. n.(23–25, ZFMK Ar 18948). 18–19. Male chelicerae, frontal and lateral views. 20–21, 23–24. Epigyna, ventral and lateral views. 22, 25. Cleared female genitalia, dorsal views. Abbreviations: ep, epigynal pocket; pp, pore plate; v, ‘valve’. Scale lines: 0.5. PALPS. As in Figs 13–14; coxa with conical retrolateral apophysis; trochanter with retrolateral apophysis; femur very large, proximally with retrolateral apophysis and prolateral hump set with short hairs; tarsus with small dorsal processes, with one strong and several regular hairs bent towards dorsal ( Fig. 14); procursus distally widened and strongly curved towards dorsal, with large ventro-distal sclerite separated from proximal part by whitish area; bulbal process with distinctive distal structures ( Fig. 15). LEGS. Without spines and curved hairs, few vertical hairs (i.e. short hairs perpendicular to leg segment); retrolateral trichobothrium on tibia 1 at 2.5%; prolateral trichobothrium present on tibia 1; tarsus 1 with ~25 pseudosegments, distally fairly distinct.  Male(variation). Males from Cruzeiro do Sul and Guajará appear identical in shape to those from Rio Branco, but the light area of the procursus is transparent rather than whitish and the black ventro-distal sclerite is slightly narrower (but the width of this sclerite is variable even among specimens from Rio Branco). Tibia 1 insix males from Rio Branco (incl. holotype): 6.4–9.2 (mean 7.7); in five males from Cruzeiro do Sul and Guajará: 8.8–10.3 (mean 9.6).  Female.In general similar to male ( Fig. 2) but carapace ochre-brown rather than yellow to orange, with larger brown median mark; ocular area slightly lower than in males; dark rings and whitish tips of femora and tibiae more distinct; clypeus less swollen and margin not sclerotized. Tibia 1 in 44 femalesfrom Rio Branco: 3.5–5.1 (mean 4.3). Epigynum as in Figs 20–21and 32–33; anterior plate with large median depression bordered posteriorly by large pocket; pair of conical lateral processes directed slightly towards posterior; posterior plate large, simple. Internal genitalia as in Figs 22, 38, with elongated pore-plates converging towards posterior and distinctive median dark anterior structure.   FIGURES 26–31.  Mesabolivar huambisaHuber, 2000. Left procursi, retrolateral views, and left bulbal processes, prolateral views; from Samiria (type locality) (26, 29, MUSM), Tabatinga (27, 30, ZFMK Ar 18950), and Belém (28, 31, ZFMK Ar 18951). Arrow points at distinctive screw-shaped sclerite. Scale lines: 0.5 (26–28), 0.3 (29–31).   FIGURES 32–47.Female epigyna in ventral and lateral views and cleared female genitalia, dorsal views,  Mesabolivar pseudoblechroscelisgroup (part 1). 32–38.  M. acrensis  sp. n., from Rio Branco (32–33, 38, ZFMK Ar 18943), Cruzeiro do Sul (34–37, ZFMK Ar 18946). 39–41.  M. maraba  sp. n.(ZFMK Ar 18948). 42–47.  M. huambisaHuber, 2000, from Samiria (42– 43, MUSM), Tabatinga (44–45, ZFMK Ar 18950), and Belém (46–47, ZFMK Ar 18951). Females from Cruzeiro do Sul and Guajará tend to have slightly longer and more pointed epigynal processes and slightly narrower median depressions; however, this varies even within localities ( Figs 34–37). As in males, females from Cruzeiro do Sul and Guajará tend to have longer legs: tibia 1 in 11 females: 4.8–5.9 (mean 5.5).  Natural history.The spiders were found close to the ground, in webs that were mostly hidden in the leaf litter, under logs, or in small cavities in the ground. A small part of the domed sheet was visible from outside, and turned into a funnel towards the back, where the spider(s) were hiding. When disturbed, they vibrated rapidly with small amplitude or tried to run away.   Distribution.Known from two localities near Rio Branco and from two localities near Cruzeiro do Sul in Acreand Amazonasstates ( Brazil) ( Fig. 722). 1835975919 [199,1045,1756,1781] Brazil Acre 9 10 1 Acre paratype 1835975913 ZFMK Br Brazil Acre 9 10 1 1 Acre paratype 1835975949 2016-10-26 2016-10-27 2016-10-26 ZFMK B. A. Huber & L. S. Carvalho Brazil Ar 225 -10.08 Fazenda Experimental Catuaba 558 -67.625 Rio Branco 9 10 19 17 2 Acre paratype 1835976030 2016-10-26 2016-10-27 2016-10-26 ZFMK Br Brazil Ar 225 -10.08 Fazenda Experimental Catuaba 558 -67.625 Rio Branco 9 10 2 2 Acre paratype 1835976035 2016-10-29 ZFMK B. A. Huber & L. S. Carvalho Brazil Ar 200 -10.078 Fazenda Experimental Catuaba 77 -67.619 Rio Branco 9 10 9 8 1 Acre paratype 1835976006 2016-10-30 ZFMK B. A. Huber & L. S. Carvalho & E. O. Machado Brazil Assigned 200 -7.596 Cruzeiro do Sul 78 -72.767 Ar 9 10 13 10 3 Acre 1835975921 2016-10-30 ZFMK Br Brazil Assigned 200 -7.596 Cruzeiro do Sul 78 -72.767 Ar 9 10 2 1 Acre