Mesabolivar baianus, Huber, 2018

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 : 43-45

Mesabolivar baianus sp. n.

Figs 140 , 153–155 , 160–164 , 191–193

Mesabolivar caipora: Huber 2015: 7 , figs 24–25, 55–56 (misidentified females; see Notes below).

Mesabolivar togatus: Astrin et al. 2006: 444 (misidentified specimens from Taiobeiras only; see Notes below).

Diagnosis. Distinguished from most known congeners by armature of male chelicerae ( Figs 153–155 ; two pairs of frontal apophyses, one oblique pair distally and one strongly projecting pair proximally), by shape of procursus ( Figs 160–161 ; in general as in M. togatus , but membranous dorsal flap more distinct: arrow in Fig. 160 ), and shape of epigynum ( Figs 162, 164 ; in lateral view like M. togatus , cf. Huber 2000: fig. 862; oval anterior plate with posterior margin divided into three lobes by whitish membrane); from the very similar M. togatus by details of distal cheliceral apophyses (smaller angle between outer margins in frontal view; clearly visible in lateral view; compare Figs 150–155 ), and by shapes of lobes on anterior epigynal plate (median lobe narrower; lateral lobes wider; compare Figs 156, 157 and 162, 164 ).

Etymology. The specific name is an adjective derived from the type locality.

Type material. BRAZIL: Bahia: ♂ holotype, 1♀ paratype, MNRJ (14309), 11♂ 11♀ paratypes, ZFMK (Ar 19031), Reserva Biológica de Una, ‘site 2’ (15°10.6’S, 39°03.5’W), ~ 50–100 m a.s.l., 4.x.2011 (B.A. Huber, A. Pérez-González, M. Alves Dias).

Other material examined. BRAZIL: Bahia: 2♂ 4♀, ZFMK ( Ar 19032), same locality but ‘site 1’ (15°11.0’S, 39°04.7’W), ~ 70–100 m a.s.l., 4.x.2011 (B.A. Huber, A. Pérez-González, M. Alves Dias) ; 2♀ 5 juvs in pure ethanol, ZFMK (Br 11-171), same data, ‘sites 1 & 2’ . 2♂ 2♀, ZFMK (Ar 19033), Reserva Ecológica da Michelin , ‘site 1’ (13°49.3’S, 39°11.9’W), ~ 140 m a.s.l., 5.x.2011 (B.A. Huber, A. Pérez-González, M. Alves Dias) ; 6♂ 10♀, ZFMK ( Ar 19034), same locality but ‘site 2’ (13°50.5’S, 39°14.5’W), ~ 140 m a.s.l., 6.x.2011 (B.A. Huber, A. Pérez-González, M. Alves Dias) ; 2♀ in pure ethanol, ZFMK (Br 11-190), same data ; 2♂ 1♀ in pure ethanol, ZFMK (Br 11-194), same data but ‘sites 1 & 2’ . 2♂, ZFMK ( Ar 19035), near Santa Teresinha, Reserva Jequitibá (12°52.19’S, 39°28.65’W), 530 m a.s.l., 13.v.2015 (B.A. Huber, L.S. Carvalho) . 6♂ 11♀, ZFMK (Ar 19036), Parque Nacional do Pau Brasil , ‘site 1’ (16°28.2’S, 39°16.8’W), ~ 65 m a.s.l., 30.ix.2011 (B.A. Huber, A. Pérez- González, M. Alves Dias) ; 6♂ 12♀, ZFMK ( Ar 19037), same locality but ‘site 2’ (outside park limits) (16°25.7’S, 39°21.1’W), ~ 60 m a.s.l., 1.x.2011 (B.A. Huber, A. Pérez-González, M. Alves Dias) ; 3♂ 3♀ in pure ethanol, ZFMK (Br 11-155), same data .

Assigned tentatively. BRAZIL: Bahia: 8♂ 3♀, ZFMK (Ar 19038), Reserva Particular do Patrimônio Natural Serra Bonita (15°23.3’–23.4’S, 39°33.7’–34.0’W), ~ 750–850 m a.s.l., 2–3.x.2011 (B.A. Huber, A. Pérez- González, M. Alves Dias) ; 2♂ 1♀ in pure ethanol, ZFMK (Br 11-163), same data . 10♀, ZFMK (Ar 12620) (erroneously assigned to M. caipora in Huber 2015 ), Mata de São João , building (12°27.7’S, 38°15.5’W), ~ 100 m a.s.l., 8.x.2011 (B.A. Huber, A. Pérez-González, M. Alves Dias).

Minas Gerais: 2♂ 1♀ in pure ethanol, ZFMK (G004), Taiobeiras [15.8°S, 42.22°W], iv.2002 (A.J. Santos).

Description. Male (holotype)

MEASUREMENTS. Total body length 4.8, carapace width 1.4. Distance PME-PME 160 µm, diameter PME 190 µm, distance PME-ALE 160 µm, distance AME-AME 30 µm, diameter AME 65 µm. Sternum width/length: 1.2/ 0.7. Leg 1: 71.3 (17.5 + 0.8 + 16.8 + 32.9 + 3.3), tibia 2: 12.0, tibia 3: 7.1, tibia 4: 11.2; tibia 1 L/d: 93. Femora 1– 4 width (at half length): 0.22, 0.24, 0.31, 0.22.

COLOR (in ethanol). Carapace ochre to light brown, with large dark brown median mark including posterior part of ocular area; sternum ochre-yellow; legs brown, tips of femora and tibiae lighter, indistinct darker rings on femora (subdistally) and tibiae (proximally and subdistally); abdomen greenish gray, dorsally and laterally densely covered with dark bluish marks, ventrally with light brown plate in front of gonopore, very indistinct plate in front of spinnerets.

BODY. Habitus as in Fig. 140 , very similar to M. togatus (cf. Huber 2000: figs 851–852); ocular area raised; carapace with distinct median furrow; clypeus unmodified; sternum unmodified.

CHELICERAE. With two pairs of frontal apophyses, proximal pair strongly projecting, distal pair oblique, angle between outer margins ~70°, clearly visible in lateral view ( Figs 153–154 ).

PALPS. In general as in M. togatus (cf. Huber 2000: figs 855–856); palps in these two species may be indistinguishable, but the membranous dorsal flap on the procursus appears to be consistently more distinct in M. baianus (arrow in Fig. 160 ).

LEGS. Without spines, without curved hairs, few vertical hairs; retrolateral trichobothrium on tibia 1 at 2.5%; prolateral trichobothrium present on tibia 1; tarsus 1 with>45 pseudosegments, distally distinct.

Male (variation). Tibia 1 in 34 other males: 14.7–18.4 (mean 16.4). Sternum often with orange color. Males from Serra Bonita and Taiobeiras with shorter proximal cheliceral apophyses ( Fig. 155 ); specimens from these localities are therefore assigned tentatively.

Female. In general similar to male but all leg femora approximately same width. Tibia 1 in 50 females: 9.7– 13.5 (mean 12.0). Epigynum as in Figs 162, 164 ; anterior plate oval, posterior margin divided into three lobes by whitish membrane, median lobe narrow (about as wide as long); lateral lobes of similar shape; large but simple posterior plate. Internal genitalia as in Figs 163 , 192 , with pair of large pore-plates in roughly vertical lateral position, slightly diverging anteriorly.

Natural history. The spiders were found in large, rather flat sheet webs, mostly close to the ground in sheltered spaces among rocks and large trees, rarely higher up and more exposed.

Distribution. Widely distributed in Bahia state ( Brazil), possibly ranging into Minas Gerais and Sergipe states ( Fig. 726 ); some of the specimens identified as M. togatus in Machado (2007) (from Sergipe: Caverna dos Aventureiros and Laranjeiras; and Bahia: Central, “Abrigo Waldemar II” – precise locality not identified) may actually belong to this species (judging from ranges of examined specimens).

Notes. The females assigned erroneously to M. caipora in Huber (2015) are extremely similar to this species; they are thus tentatively assigned to it. However, the internal genitalia differ slightly (compare Huber 2015: figs 25 and 56 and Figs 163 , 192 herein) and the legs of those specimens are consistently shorter (tibia 1: 7.3–9.5 vs. 9.7–13.5). In the absence of males from this locality (Mata de São João, Bahia), the identity of these females remains unclear.

The specimens from “Taisbeiras” (typo for Taiobeiras) identified as M. togatus in Astrin et al. (2006) closely resemble unambiguous M. baianus but are tentatively assigned to this species for the lack of males from this locality. Their genetic distance to specimens from São Paulo sequenced in Astrin et al. (2006) supports the distinction between M. togatus and M. baianus (CO1, raw p-distance: 6.6%, K2P-corrected: 7.0%).

Figures

FIGURES 138–149. Live specimens, Mesabolivar togatus group. 138–139. M. togatus (Keyserling, 1891), males from Sooretama (with Arachnocoris bug; arrow) and Santa Maria Madalena. 140. M. baianus sp. n., male from Serra Bonita. 141– 142. M. similis sp. n., male and female from Morro de Pedra.143–144. M. buraquinho sp. n., male from Bonito, female from Mata do Buraquinho.145–146.M.caiporaHuber, 2015,male and femalefrom Serra daItabaiana.147. M.inmanis sp. n., male from Vargem Alta.148–149.M.cyaneomaculatus (Keyserling, 1891), males from Penedo.

FIGURES150–155. Male chelicerae, frontal and lateral views.150–152. Mesabolivar togatus (Keyserling, 1891), males from Guapiaçú (150–151; ZFMK Ar 19017) and Rio das Pedras (152; ZFMK Ar 19021). 153–155. M. baianus sp. n., males from Una (153–154; ZFMK Ar 19031) and Serra Bonita(155; ZFMK Ar 19038).Arrows point at distal cheliceral ledges.Scale line: 0.5 (all at same scale).

FIGURES156–164.Mesabolivar togatus(Keyserling, 1891) (156–159), and M.baianus sp. n. (160–164).156–157, 162, 164. Epigyna,ventral views, females from Guapiaçú (156; ZFMK Ar 19017), Sooretama (157; ZFMK Ar 19029), Una (162; ZFMK Ar 19031), and Serra Bonita (164; ZFMK Ar 19038). 158–161. Tips of left procursi, prolateral and retrolateral views (ZFMK Ar 19017 and 19031) (arrows point at slightly differing membranous dorsal flaps). 163. Cleared female genitalia, dorsal view (ZFMK Ar 19031).Scale lines:0.5 (156–157, 162–164; all epigyna at same scale); 0.3 (158–161; all procursi at same scale).

FIGURES188–199. Femaleepigyna in ventral views and cleared female genitalia in dorsal views, Mesabolivar togatus group (part 1). 188–190.M.togatus (Keyserling, 1891), from Guapiaçú (188–189, ZFMK Ar 19017) and Sooretama (190, ZFMK Ar 19029).191–193.M.baianus sp. n., from Una (191–192, ZFMK Ar 19031) and Serra Bonita (193, ZFMK Ar 19038). 194.M. similis sp. n. (ZFMK Ar 19039). 195–196. M. camacan sp. n. (ZFMK Ar 19040). 197. M. buraquinho sp. n. (ZFMK Ar 19042).198–199.M.caiporaHuber, 2015, from São João (198, ZFMK Ar19062) and Mata do Crasto (199, ZFMK Ar 19060).

FIGURES726–729. Knowndistribution of the Mesabolivar togatusgroup.“?”: dubious recordsof M.togatus, possible record of M. baianus (sub. M. togatus in Machado 2007), and of M. cyaneomaculatus from Paraná (Mello-Leitão 1947b); asterisk: erroneous record of M.togatusfrom Pará in Mello-Leitão (1940a).TL, type locality.