Ayacucho silvae, Benedetti & Pinto-da-Rocha, 2022

Benedetti, Alipio Rezende & Pinto-da-Rocha, Ricardo, 2022, Systematic revision and total evidence phylogenetic analysis of the Andean family Metasarcidae Kury, 1994 (Opiliones: Laniatores), with description of two new genera and twenty new species, Arthropod Systematics & amp; Phylogeny 80, pp. 309-388 : 309

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Ayacucho silvae

sp. nov.

3.19. Ayacucho silvae sp. nov.

Figs 2I View Figure 2 , 7M, N View Figure 7 , 15 G-I View Figure 15 , 22E, F View Figure 22 , 28 View Figure 28


MALE: Measurements (n =10) DSW: 1.7-3.0 (2.8); DSL: 4.0-4.3 (4.2); CL: 1.3-1.5 (1.5). FIVL: 2.6-2.8 (2.6). ChL: 1.2-2.5 (2.2). Coloration: (Fig. 22E View Figure 22 ) Carapace and lateral margins of dorsal scutum yellowish. Scutal areas and posterior margin of dorsal scutum and free tergites brown, with yellowish spots. Legs trochanters yellow, other segments brown. Chelicerae yellow. Pedipalpus brownish. Dorsum: (Fig. 2I View Figure 2 ) Alpha-type DSS. Anterior margin of the dorsal scutum completely covered with granules, with median elevation. Ocularium robust, with granules of equal size throughout its length in smaller males, larger males with a pair of small acuminate tubercles. Carapace densely covered with granules. Areas I-IV without larger granules. Posterior margin of the dorsal scutum and free tergites with rows of tubercles, in greater numbers in posterior margin than in free tergites. Chelicerae: (Fig. 2I View Figure 2 ) Swollen in larger males (as in the holotype) and at similar size of females in smaller males. Segment I granulate. Segment II predominantly smooth; finger with one tooth. Segment III with one tooth. Pedipalpus : Small granules distributed on the dorsal surface. Trochanter with a ventrodistal setiferous tubercle. Femur with ventrobasal setiferous tubercles, one ventral row of five small setiferous tubercles, distributed throughout the length of segment except at apex. Tibia: prolateral I(i)Ii, retrolateral IIIII. Tarsus: prolateral IIII, retrolateral III. Venter: Coxae I-IV with scattered small granules. Genital area with few granules. Free sternites I-IV with rows of small granules. Anal operculum with granules sparsely distributed throughout its surface. Legs: (Figs 2I View Figure 2 , 7M, N View Figure 7 ) Coxae I-II with an anterior and a posterior apophysis. Coxa IV with granules distributed throughout its length. Trochanters I-IV somewhat granulate, unarmed. Femora I-IV with granules densely distributed throughout their dorsal, retrolateral and prolateral surfaces, the ventral surface of femora I-III with two rows of granules, larger than other granules of those segments; femur IV with two ventral rows (in ⅔ distal) of tubercles that increase in size distally, whose size is more pronounced in large males. Patellae I-IV with granules distributed predominantly in the dorsal, retrolateral and prolateral faces, being scarcer ventrally. Tibiae I-IV with granules throughout their length, higher on the ventral side. Tarsal formula: (n = 10) 5-6 (6), 7-8 (8), 6, 6-7 (7). Penis: (Fig. 15G-I View Figure 15 ) VP subrectangular, slightly convex, with lateroapical projections. MS C1-C3 subapical, long and straight; MS A1 median, long and straight (smaller than MS C); MS B1-B2 sub basal, long and straight (MS B1 longer than MS B2). Lateral sacs long and apically acuminate, with long T3-like microsetae. Stylus with apex inflated, with several apical projections and a small dorsal projection. Dorsal process absent. Promontory convex. - FEMALE: Measurements (n =12) DSW: 1.8-3.1; DSL: 4.0-4.2; CL: 1.3. FIVL: 2.8-3.0. ChL:1.2-1.4 (Fig. 22F View Figure 22 ) Chelicerae slightly smaller than those of small males. Presence of a proapical setiferous tubercle on pedipalpus femur, larger than the tubercles of the ventral surface. Femur IV slightly thinner, with smaller granules and distal two rows of tubercles absent. Tarsal formula: (n = 12) 6-7, 8, 6, 5-6.


Similar to Ayacucho glauberrochai sp. nov., A. pomacocha sp. nov., A. titschacki and A. vargasllosai sp. nov. in the following combination of characteristics: dorsal scutum densely granulate; ocularium and areas I-IV of DS unarmed or armed with tiny tubercles, slightly greater than granules; posterior margin of DS and free tergites I-III with median rows of acuminate tubercles (Fig. 2I View Figure 2 ). It differs from the previously mentioned species in the following combination of characteristics: ocularium unarmed and densely granulate (Fig. 2I View Figure 2 ); male femur IV with ventral surface armed (Fig. 7N View Figure 7 ); penis VP subrectangular; three pairs of subapical MS C; two pairs of MS B (Fig. 15G-I View Figure 15 ).

Derivatio nominis.

The specific epithet of feminine gender, in the genitive form, dedicated to Dr. Diana Silva D. (MUSM), for her contribution to the knowledge of Peruvian arachnids.


(Fig. 28 View Figure 28 ) PERU. Pasco. Near to Cerro de Pasco.

Material examined.

Type material: Holotype ♂, ' PERU, Pasco, Near to Cerro de Pasco, 10°41′39″S 76°13′08″W, 23/IV/2011, R. Pinto-da-Rocha, A. Benedetti, J. Ochoa & D. Silva leg. (MUBI) GoogleMaps - Paratypes 2 ♂, 5 ♀, ‘ditto’ (MUBI); Paratypes 2 ♂, 5 ♀, ‘ditto’ (MUSM); Paratypes 5 ♂, 11 ♀, ‘ditto’ (MZSP 36971).