Schendylops grismadoi sp. nov.

(Figs. 1–59)

Diagnosis. A Neotropical species of Schendylops with pore-field area on first sternite; pore-fields present in an uninterrupted series all along the body; pore-fields undivided on anterior and posterior sternites, divided in two subsymmetrical areas on intermediate sternites; posterior limit of ventral pore-field series on penultimate sternite. The other Neotropical members of the genus sharing these combined traits are S. tropicus (Brölemann & Ribaut, 1911), S. inquilinus Pereira, Uliana & Minelli, 2007, S. coscaroni (Pereira & Minelli, 1996), S. demelloi (Verhoeff, 1938), and S. parahybae (Chamberlin, 1914) . S. grismadoi sp. nov. differs from the latter taxa by having the following unique traits: anterior margin of cephalic plate conspicuously notched in the middle (Fig. 10); dentate lamellae of mandibles divided in two blocks (Figs. 13–15); basal internal edge of forcipular tarsungulum with a small pigmented tooth (Figs. 21–23).

Other morphological traits included in Table 2 differentiate S. grismadoi sp. nov. from the other five abovementioned species.

Remarks. For details on features differentiating S. grismadoi sp. nov. from some other Neotropical species of Schendylops, see comments on morphological similarities below, and Table 3.

The new species can be separated from the Neotropical members of Schendylops having sternal pore-fields all along the body, by using the identification key below.

Type material examined. BOLIVIA: Santa Cruz Department: Guarayos Province: 15º 42´42´´ S, 62º 46´20´´ W (La Chonta forestry concession), 330 m a.s.l., Amazon forest, 26–30 October 2010, C. J. Grismado, M. R. Vacaflores & M. Pérez leg.: holotype ♀ 45 leg-bearing segments, body length 27 mm.

Depository of type. CBF.

Description. Female holotype. Forty-five leg-bearing segments, body length 27 mm, maximum body width 0.85 mm, maximum width of cephalic plate 0.57 mm, length of cephalic plate 0.59 mm, maximum width of forcipular coxosternite 0.78 mm. Colour (of preserved specimen in alcohol): head, forcipular segment and legbearing segments 1–7 (-8) bright ferrugineous, rest of the body pale orange-brownish.

Antennae. About 3.1 times as long as the cephalic plate, distally attenuate, ratio of width of a.a. I/width of a.a. XIV ca. 2.29: 1, width of a.a. II/width of a.a. XIV ca. 1.75: 1. A.a. I nearly as long as wide, all remaining a.a. longer than wide. Ventral chaetotaxy: setae on a.a. I–IV of various lengths and relatively few in number; those of a.a. V–XIV progressively shorter and more numerous towards the tip of the appendage (Fig. 1). Dorsal chaetotaxy: setae on a.a. I–IV similar to the ventral side, setae on remaining a.a. a little longer and slightly less numerous. A.a.

XIV with ca. 16 claviform sensilla on the external margin and ca. 6 on the internal margin (Fig. 2: c); distal end of this a.a. with ca. 5 small hyaline specialized sensilla ending in three small apical branches (Fig. 2: d). Ventral and dorsal surface of a.a. II (Figs. 3, 6), V (Figs. 4, 7), IX (Figs. 5, 8) and XIII (Figs. 2, 9) with very small specialized sensilla placed on hyaline, unreticulated, unpigmented areas. On the ventral side these sensilla are placed on the middle and internal latero-apical area and are represented by two different types (a and b). Type a sensilla very thin and not split apically (Fig. 5: a), type b sensilla (Fig. 5: b) very similar to those of the apex of a.a. XIV. Specialized sensilla on dorsal side restricted to a middle and external latero-apical areas and are represented by three different types: a and b similar to a and b of ventral side (Fig. 7: a, b) and type c sensilla, similar to type b, but darker (ochreous in color) (Fig. 7: c). Relative position of specialized sensilla on ventral and dorsal surfaces of the specified a.a. as in Figs. 2–5 and 6–9 respectively. Number and distribution of type a, b, and c sensilla as in Table 1.

Ventral Dorsal Figs. a b a b c

II - 1 1 2 - 3, 6 V 1 2 1 2 1 4, 7 IX 1 1 1 2 3 5, 8 XIII 1 1 1 1 4 2, 9 Cephalic plate. Nearly as long as wide, anterior margin strongly notched in the middle (Fig 10: a), lateral margins slightly concave anteriad, covex on remaining parts, posterior margin concave. Shape and chaetotaxy as in Fig. 10.

Clypeus. With 1+1 postantenal setae, 9+8 median setae and 1+1 prelabral setae (Fig. 11).

Labrum. Mid-piece with 15 sclerotized pigmented teeth, of which the eleven most central are round tipped, and the 2+2 lateral have an acute apex (Fig. 12). Side pieces with 4+5 less sclerotized teeth, each with a very sharp medial extension (Fig. 12).

Mandible. Dentate lamellae subdivided into two distinct blocks, with 5, 6 teeth in the right mandible (Fig. 15) and 3, 8 in the left (Figs. 13, 14), pectinate lamella with ca. 21 hyaline teeth.

First maxillae. Coxosternite and telopodites with well developed lappets (Fig. 16). Coxosternite with 2+2 setae; coxal projections subtriangular, round tipped and provided with 1+1 large setae and 0+1 small setae (Fig. 17). Article 2 of telopodites with 3+3 ventral setae (Fig. 17) and 5+5 dorsal sensilla (Fig. 16).

Second maxillae. Coxosternite bearing 11+10 setae with relative size and arrangement as in Fig. 17. Shape of postero-external regions as in Figs. 18–19. Apical claw of telopodites well developed, bipectinate, ventral edge (Fig. 20) with ca. 14 teeth, dorsal edge with ca. 16–18 teeth.

Forcipular segment. When closed the telopodites do not reach the anterior margin of the head. Forcipular tergite trapeziform, with anterior margin concave, lateral margins straight converging anteriad (Fig. 22); chaetotaxy represented by an irregular transverse median row of ca. 6 large setae and other additional smaller setae distributed on the remaining surface (Fig. 22). Telopodites with trochanteroprefemur, femur and tibia unarmed (Figs. 21, 22). Tarsungulum with a small pigmented tooth on the basal internal edge (Figs. 21–23). Length/width ratio of forcipular trochanteroprefemur ca. 1.27: 1. Calyx of poison gland cylindrical (Fig. 23: b). Shape and chaetotaxy of coxosternite and telopodites as in Figs. 21, 22.

Sternites of leg-bearing segments 1 to penultimate. Ventral glands pale yellow in color; pore-fields present in an uninterrupted series from sternite 1 to penultimate inclusive. Fields undivided on sternites 1–15 and 40–44, divided in two subsymmetrical areas on sternites 16–39. Pore-field on sternite 1 accompanied by two additional pores on the right side and one on the left side of the anterior border (Fig. 24). Pore-fields on sternites 3–9 accompanied by one-two additional pores at each lateral border, some of them virtually integrated to the main porefield area, Figs. 26, 27, 28, 29, 30, 31 (sternites 3, 4, 5, 7, 8, 9 respectively). Shape and relative size of fields changing along the trunk as in Figs. 24–44. Number of pores on selected sternites as follows: sternite 1 (2+17+1 pores); 2 (52); 3 (1+72+1); 4 (1+84+1); 5 (1+83+1); 7 (2+92+1); 8 (2+88+2); 9 (2+99+0); 10 (99); 15 (0+92+1); 16 (47+50); 17 (34+32); 27 (16+13); 34 (14+12); 35 (11+19); 39 (12+15); 40 (42); 41 (44); 42 (49); 43 (60); 44 (42).

TABLE 2. Differential characters of Schendylops grismadoi sp. nov., S. tropicus (Brölemann & Ribaut, 1911), S. inquilinus Pereira, Uliana & Minelli, 2007, S. coscaroni (Pereira & Minelli, 1996), S. demelloi (Verhoeff, 1938), and S. parahybae (Chamberlin, 1914) .

Body length 27 mm (♀) 16 mm (♀) 31 mm (♀) 28 mm (♀) 70 mm (♀) 38 mm (♀)

29 mm (♂) 36 mm (♂) 51 mm (♂)

Body width 0.85 mm (♀) 0.7 mm (♀) 0.8 mm (♂) 1.2 mm (♀) 2.0 mm (♀) 1.0 mm (♀)

1.8 mm (♂) Anterior margin of cephalic yes (Fig. 10) no no (Fig. 75) no no no plate conspicuously notched

the middle

Proximal a.a. with few setae ♀: I – IV? ♀ and ♂: I-III (-IV) ♀: I-III (-IV) ♀: I-II? different lengths ♂: I ♂: I

……continuedonthenextpage TABLE 2. (Continued)

S. grismadoi S. tropicus S. inquilinus S. coscaroni S. demelloi S. parahybae

Number of teeth on labrum ca. 15 ca. 13-14 ca. 11 ca. 16 ca. 19? mid-piece

……continuedonthenextpage TABLE 2. (Continued)

S. grismadoi S. tropicus S. inquilinus S. coscaroni S. demelloi S. parahybae

Number of setae on with a an irregular? with an irregular with an irregular with ca. 90 setae with an irregular forcipular tergite transverse median row transverse median row transverse median row dispersed on almost transverse median row

of ca. 6 large setae and of ca. 11 large setae and of ca. 12 large setae and whole surface of ca. 12 setae

a few additional smaller a few additional smaller a few additional smaller

setae (Fig. 22) setae setae

Length/width ratio of ca. 1.27: 1? ca. 1.13: 1 ca. 1.30: 1 ca. 1.0: 1 ca. 1.33: 1 forcipular

trochanteroprefemur

internal edge of yes(Figs.21-23) no no no no no forcipular tarsungulum with

small pigmented tooth

……continued on the next page TABLE 2. (Continued)

S. grismadoi S. tropicus S. inquilinus S. coscaroni S. demelloi S. parahybae Female postpedal segments: yes (Fig. 55)? yes (Fig. 83) yes (Fig. 65) no (with ca. 75 small yes (Fig. 95) intermediate sternite with a setae, Fig. 70) large setae

Legs (pair 1 to penultimate). Chaetotaxy similar throughout the entire body length. Distribution, number and relative size of setae as in Figs. 46–51. Claws ventrobasally with three thin and pale accessory spines (one anterior and two posterior), shape and relative size as in Figs. 52, 53.

Ultimate leg-bearing segment. Intercalary pleurites present at both sides of the ultimate pretergite (Fig. 54). Ultimate presternite not divided along the sagittal plane; width/length ratio of the tergite ca. 1.30: 1; width/length ratio of the sternite ca. 1.40: 1. Shape and chaetotaxy of tergite and sternite as in Figs. 54, 55. Coxopleura slightly protruding at their distal ventral ends, chaetotaxy represented by small and moderately numerous setae on the distal-internal ventral area, the remaining surface with few large and small setae (Figs. 54, 55). Two single (“homogeneous”) coxal organs in each coxopleuron, both organs unilobed (Figs. 58). Relative size of coxal organs in respect to the size of coxopleura and sternite as in Fig. 55. Coxal organs open on the membrane between coxopleuron and sternite partially or totally covered by the latter (Fig. 55). Ultimate legs composed of seven articles. Ratio of width of tarsus 1/width of tarsus 2, ca. 1.25: 1; ratio of length of tarsus 2/length of tarsus 1, ca. 1.34: 1. Ratio of length of telopodites of ultimate legs/length of sternite ca. 4.0: 1. Shape and chaetotaxy of articles of ultimate legs as in Figs. 54, 55. Ultimate pretarsus represented by a pale, rudimentary terminal tubercle with one diminutive apical spine (Figs. 56, 57).

Postpedal segments. Intermediate tergite with posterior margin strongly convex (shape and chaetotaxy as in Fig. 54), intermediate sternite with posterior margin slightly concave; first genital sternite nearly straight (shape and chaetotaxy as in Fig. 55). Gonopods uniarticulate, well separated on the sagittal plane bearing 5+5 setae (Fig. 55, 59: a).

Male. Unknown.

Remarks. The adult (and mated) condition of the female holotype is indicated by the presence of spermatozoa in both spermathecae (located at level of leg-bearing segments 41–43, Fig. 45).

Etymology. The species is respectfully dedicated to one of the collectors of the type specimen described herein, the distinguished arachnologist Cristian José Grismado of the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” (CONICET), Buenos Aires, Argentina.

Ecology. The holotype specimen was collected in leaf litter in a subhumid tropical forest environment, in a selective logging area (“La Chonta” forestry concession), at about 300 m a.s.l., east-central Bolivia (Amazon basin). (For climatic features and other traits of the forest at La Chonta, see introduction above).

Type locality. BOLIVIA: Santa Cruz Department: Guarayos Province: 15º 42´43´´ S, 62º 46´20´´ W.

Known range. Only known from the type locality.

Neotropical members of Schendylops morphologically similar to S. grismadoi sp. nov. In the differential diagnosis above, the new species has been compared in detail with the other Neotropical species characterized by having an uninterrupted series of ventral pore-fields, extending from first to penultimate sternite (undivided on anterior and posterior sternites, divided in two subsymmetrical areas on the intermediate). The Neotropical members with pore-field series, ending instead on the antepenultimate sternite (but sharing all remaining mentioned traits) are S. amazonicus (Pereira, Minelli & Barbieri, 1994), S. borellii (Silvestri, 1895), S. iguapensis (Verhoeff, 1938), S. longitarsis (Silvestri, 1895), S. marchantariae (Pereira, Minelli & Barbieri, 1995), and S. mesopotamicus (Pereira, 1981) . S. grismadoi can be differentiated from the latter by means of the following unique features: anterior margin of cephalic plate conspicuously notched in the middle (Fig. 10); basal internal edge of forcipular tarsungulum with a small pigmented tooth (Figs. 21–23). Among the aforementioned taxa those having a number of leg-bearing segments roughly similar to S. grismadoi are S. iguapensis and S. marchantariae; the selected morphological traits included in Table 3 differentiate the new species from the latter two.