Ochyrocera ritxoco, Brescovit & Zampaulo & Cizauskas, 2021

Brescovit, Antonio D., Zampaulo, Robson de A. & Cizauskas, Igor, 2021, The first two blind troglobitic spiders of the genus Ochyrocera from caves in Floresta Nacional de Carajas, state of Para, Brazil (Araneae, Ochyroceratidae), ZooKeys 1031, pp. 143-159 : 143

Ochyrocera ritxoco sp. nov. Figs 1 , 2 , 3 , 4 , 5 , 6 , 10

Type material.

Holotype male from Cave N1_0103 (GEM-1301 or Cipó cave; 6°0'13"S, 50°17'55"W), FLONA de Carajás, Parauapebas, Pará, Brazil, 28/XI-03/X/2007, R. Andrade et al. col. (IBSP 115497). Paratype female from Cave N1_0075 (GEM_1273 or Piranha cave; 6°1'14"S, 50°16'49"W), FLONA de Carajás, Parauapebas, Pará, Brazil, 28/XI-03/X/2007, R. Andrade et al. col. (IBSP 115499).

Other material examined.

Brazil. Pará: Parauapebas, FLONA de Carajás, Cave N 1_0015 (GEM-1211) (6°2'2"S, 50°16'16"W), 11/VI-02/VII/2014 , 1♀ (IBSP 186123); 1♀ (IBSP 186124); 1♂ (IBSP 186125); 2♀ (IBSP 186126); Cave N1_0016 (GEM-1212) (6°1'10"S, 50°16'41"W), 04/IX-06/X/2014, 1♀ (IBSP 186130); 02-29/IV/2015, 2♀ (IBSP 186153); 3♀ (IBSP 186154); 1♀ (IBSP 186155); Cave N1_0055 (GEM-1253) (6°1'12"S, 50°16'43"W), 07-28/I/2015, 1♀ (MPEG 37086, ex IBSP 186147); Cave N1_0056 (GEM-1254) (6°1'11"S, 50°16'44"W), 07-28/I/2015, 1♂ (MPEG 37087, ex IBSP 186148); 1♂ 1♀ (IBSP 186149); Cave N1_0060 (GEM-1258) (6°1'12"S, 50°16'41"W), 11/VI-02/VII/2014, 1♀ (IBSP 186127); 1♀ (IBSP 186128); 07-28/I/2015, 1♀ (IBSP 186150); 1♀ (IBSP 186151); 1♂ 1♀ (MPEG 37088, ex IBSP 186152); Cave N1_0062 (GEM-1260) (6°1'10"S, 50°16'44"W), 04/IX-06/X/2014, 1♀ (IBSP 186131); 1♀ (IBSP 186132); 2♀ (IBSP 186133); 1♀ (IBSP 186134); 1♂ 2♀ (IBSP 186135); 02-29/IV/2015, 2♀ (IBSP 186157); 3♂ 1♀ (IBSP 186156); 1♀ (IBSP 186158); Cave N1_0073 (GEM-1271) (6°1'13"S, 50°17'17"W), 02-29/IV/2015, 1♀ (IBSP 186159); 1♂ (IBSP 186160); 1♀ (IBSP 186161); 1♀ (IBSP 186162); Cave N1_0084 (GEM-1282) (6°1'7"S, 50°17'1"W), 11/VI-02/VII/2014, 1♀ (IBSP 186129); Cave N1_0101 (GEM-1299) (6°1'9"S, 50°16'46"W), 04/IX-06/X/2014, 1♂ (IBSP 186136); 1♀ (IBSP 186137); 1♀ (IBSP 186138); 1♂ (IBSP 186139); 2♀ (IBSP 186140); 1♂ (IBSP 186141); 1♂ (IBSP 186142); Cave N1_0240 (6°1'19"S, 50°16'26"W), 04/IX-06/X/2014, 1♂ (IBSP 186143); 1♀ (IBSP 186144); 1♂ (IBSP 186145); 1♀ (IBSP 186146); 02-29/IV/2015, 1♀ (IBSP 186163); 1♂ 1♀ (IBSP 186164); all collected by Equipe Carste; Cave N4WS_0067 (GEM-1846) (6°04'22"S, 50°11'30"W), 18/XI-01/XII/2010, F.P. Franco & C.A.R. Souza et al. col ., 1♂ (IBSP 174069); 2♀ (IBSP 174070); Piranha, Cave N1-75 (6°1'14"S, 50°16'49"W), 28/IX-03/X/2007, 1♂ 2♀ (IBSP 260307; 1♂ SEM; 1♀ SEM, ex IBSP 115499); all collected by R. Andrade et al.

Diagnosis.

Ochyrocera ritxoco sp. nov. is distinguished from O. ritxoo sp. nov. by having an elongated embolus, which is two times longer than the bulb in the male palp (Figs 1F , 2A, B , 4E-G ), while the embolus is one times longer than the bulb in O. ritxoo sp. nov. (Fig. 7C, D ); a long and globose distal area in the spermathecae and an elongated columnar uterus externus with approximately eight internal chambers in the female genitalia (Fig. 2C, D ); while O. ritxoo sp. nov. have a triangular distal area in the spermathecae and a shorter columnar uterus externus with 3-4 internal chambers in the female genitalia (Fig. 8C, D ).

Description.

Male (Holotype). Total length 1.1. Carapace length 0.45; ovoid, narrowing gradually anteriorly, yellowish and bright, pars cephalic flat, fovea absent (Figs 1A , 3A ). Clypeus with two pairs of long bristles (Fig. 3A ). Eyes absent. Chelicerae light yellow with orange fang, promargin with three teeth attached to a very long lamina (Fig. 3B ), retromargin without teeth. Endites light yellow with large serrula with more than 30 denticles, distal macrosetae paired and crosier-like, many multifid macrosetae present (Fig. 3C, D ). Labium cream-colored, rounded with 8-10 setae with an enlarged basally (Fig. 3C ). Sternum light yellow. Legs cream-colored, formula 1423, total length I 4.5, II 3.8, III 3.1, IV 4.0. Male palp with palpal femur length 0.04, palpal tibia almost as long as wide with two long dorsal trichobothria (Fig. 3F ), cymbium enlarged basally, narrowed distally, bearing elongated cuspule (Fig. 4D ), three setae on projected bases retrolaterally (Fig. 4A, B ), elongated tarsal organ subdistally (Fig. 4C ), no basal setae on the rounded cymbial prolateral extension, bulb oval, embolus filiform, sinuous and at least twice as long as the cymbium (Figs 1F , 2A, B , 4E-G ). Abdomen length 0.50, oval, uniformly gray. Six epiandrous spigots with a short base (Fig. 3E )

Female (Paratype IBSP 115499). Total length 1.15. Carapace length 0.55 as in male with light yellowish pattern (Figs 1B , 5A ). Pedipalp without claw, with conical tip and subdistal trichobothrium (Fig. 5D-E ). Clypeus, eyes, chelicerae (Fig. 5B ), sternum, endites, and labium as in male. Legs as in male, formula 4123, total length I 4.1, II 3.6, III 2.4, IV 4.3. Claw of leg with five teeth (Fig. 5F ). Abdomen length 0.65. Colulus rectangular with five long bristles (Fig. 5C ). Internal genitalia with long spermathecae narrowed at tip, conspicuous pore-plate at base; medial columnar uterus externus long, with visible internal chambers. Uterus externus shorter than spermathecae. Oval pore-plates on spermathecae with approximately 20-30 glandular ducts (Fig. 2C, D ).

Variation.

Ten males: total length 1-1.25; carapace 0.4-0.5; femur I 1.05-1.4; ten females: total length 1-1.3; carapace 0.4-0.5; femur I 1-1.3.

Etymology.

The specific name Ritxòkò means "ceramic dolls" in the female language of the Karajá people, an indigenous population of the region. The dolls are produced by Karajá women, who model, burn, paint, and sell them ( Silva 2015).

Natural history.

Ochyrocera ritxoco sp. nov. is a small troglobitic spider that is exclusive to caves in the Carajás karst region. Specimens were found only in aphotic zones of caves. They build small, tangled webs under blocks of stone on the ground or in slits (Fig. 6 ). The observed sex ratio for the species was 2.4F:1M (N = 66). Ochyrocera ritxoco sp. nov. was generally found in large cavities with horizontal projections varying from 9.5 to 216 meters (N = 13, mean = 107 m). All caves where the species was found have only one entrance and are located only in the middle and high slopes of Serra Norte. Most caves have aphotic zones or twilight zones (except for cavities N1_0103 and N1_0084) and high humidity, thus explaining the observed presence of small bodies of water in almost all cavities, especially during the wet season. The number of troglobitic species in these caves varied from one to ten (average 5.3 per cave), with species of the following taxa: spiders - Oonopidae (many species), Caponiidae ( Carajas paraua Brescovit & Sánchez-Ruiz, 2016) and Ochyroceratidae ( Speocera spp.); pseudoscorpions - Bochicidae , Chthoniidae and Ideoroncidae ; springtails - Paronellidae ( Trogolaphysa sp., Cyphoderus sp.), Entomobryidae ( Pseudosinella sp.) and Sminthuridae ( Pararrhopalites sp.); beetles - Carabidae ( Coarazuphium spp.), Dytiscidae ( Copelatus cessaima Caetano, Bena & Vanin, 2013); isopods - Scleropactidae ( Circoniscus spp.), Calabozoidae ; amphipods - Bogidiellidae ( Bogidiella sp.); planarian - Prorhynchidae ( Geocentrophora sp.); and Harvestmen - Escadabiidae .

Distribution.

Known exclusively from caves in a range of approximately 15 km of the Serra Norte (North Mountain), FLONA de Carajás, Parauapebas, state of Pará, northern Brazil (Fig. 10 ).

Figures

Figure 1. Ochyrocera ritxoco sp. nov., male IBSP 186160 (A, C-F), female IBSP 186146 (B) A, B habitus, dorsal view C left male palp, retrolateral view D same, prolateral view E right male palp, ventral view F same, dorsal view. Abbreviations: C = cymbium, CE = cymbial extension, E = embolus, T = tegulum.

Figure 2. Ochyrocera ritxoco sp. nov. (A, B) A left male palp IBSP 186149, retrolateral view B same, prolateral view (C, D) C female genitalia IBSP 186149, enzyme cleared, dorsal view D same, dorsal view. Abbreviations: C = cymbium, CUE = columnar uterus externus, E = embolus, NUE = neck of uterus externus, PP = pore-plate, SP = spermathecae, T = tegulum, UE = uterus externus.

Figure 3. SEM images of Ochyrocera ritxoco sp. nov., male IBSP 260307 (A-F) A carapace, dorsal view B chelicerae, frontal view C endites and labium, ventral view D crosier-like macrosetae (arrow, detail) E epiandrous area, abdomen, ventral view F male palp, tibia (arrows, trichobothria), dorsal view.

Figure 4. SEM images of Ochyrocera ritxoco sp. nov., male IBSP 260307 (A-G) A cymbium, retrolateral view B same, basal macrosetae, retrolateral view C same, tarsal organ, detail, retrolateral view D same, apex detail E-G male palp, arrows indicating the embolus E retrolateral view F same, prolateral view G same, frontal view.

Figure 5. SEM images of Ochyrocera ritxoco sp. nov., female IBSP 260307 (A-F) A carapace, dorsal view B chelicerae, frontal view C colulus, ventral view D pedipalp, distal, prolateral view E same, tarsal organ F leg IV, claw, prolateral view.

Figure 6. Ochyrocera ritxoco sp. nov., female in webs under rocks on the ground in the Cave N 4 WS _ 0067.

Figure 7. Ochyrocera ritxoo sp. nov., male IBSP 193194 (A, C-F), female IBSP 193196 (B) A, B habitus, dorsal view C left male palp, retrolateral view D same, prolateral view E right male palp, dorsal view F same, retro-ventral view. Abbreviations: C = cymbium, CE = cymbial extension, E = embolus, T = tegulum.

Figure 8. Ochyrocera ritxoo sp. nov. (A, B) A left male palp IBSP 193194, retrolateral view B same, prolateral view (C, D) C female genitalia IBSP 1741071, enzyme cleared, dorsal view D same, dorsal view. Abbreviations: C = cymbium, CE = cymbial extension, CUE = columnar uterus externus, E = embolus, NUE = neck of uterus externus, PP = pore-plate, SP = spermathecae, T = tegulum, UE = uterus externus.

Figure 10. Distribution map of Ochyrocera ritxoco sp. nov., yellow triangles, and Ochyrocera ritxoo sp. nov., red plus signs, in FLONA de Carajas, Para, Brazil.