Metasarcus beni, 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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Metasarcus beni

sp. nov.

3.40. Metasarcus beni sp. nov.

Figs 5A View Figure 5 , 10A, B View Figure 10 , 14C, D View Figure 14 , 31 View Figure 31


MALE: Measurements (n =2) DSW: 5.0-5.1 (5.1); DSL: 5.0-5.2 (5.2); CL: 1.2-1.3 (1.3). FIVL: 16.0-17.0 (17). ChL: 3.3-3.4 (3.4). Coloration (in ethanol): Yellow. Dorsum: (Fig. 5A View Figure 5 ) Gamma-P-type DSS. Anterior margin of carapace with median elevation, with few granules. Carapace with granules concentrated in the lateral regions to ocularium and sparse behind ocularium. Ocularium with pronounced median depression; granulate and unarmed. Areas I-II granulate; III-IV with sparse granulation. Area I divided by longitudinal groove; with one pair of median tubercles. Areas II and IV unarmed. Area III with two long spines, directed posteriorly. Posterior margin of dorsal scutum and free tergites with few granules distributed. Lateral margins of dorsal scutum with granules along the posterior ⅔. Chelicerae: (Fig. 5A View Figure 5 ) Swollen. Segment I granular. Segment II with few granules; finger with seven teeth. Segment III with four teeth. Pedipalpus : Femur-tibia with small tubercles on dorsal surface. Trochanter with a ventroapical setiferous tubercle. Femur a ventral row of 5-6 large spines; a large retroapical spine. Patella with a large retroapical and smaller proapical spines. Tibia: prolateral IIII, retrolateral IIII. Tarsus: prolateral IIi, retrolateral iIi. Venter: Coxa I with a row of 5-6 tubercles. Coxae II-IV with sparse granules. Rows of four tiny tubercles between coxae II-III and six tubercles between coxae III-IV. Genital area, free sternites and anal operculum few granulate. Legs: (Figs 5A View Figure 5 , 10A, B View Figure 10 ) Coxae I-II each with a prolateral and a retrolateral apophysis. Coxa III unarmed. Coxa IV with few sparse granules. Trochanters I-III unarmed and smooth. Trochanter IV unarmed and granular. Femora I-III unarmed and with small granules. Femur IV granular; a distal retrodorsal small apophysis; a distal retroventral row of 11-12 small tubercles. Patella-tibiae I-IV unarmed, with few granules. Tarsal segmentation (n =2) 7, 16-17 (17), 10, 11-12 (12). Penis: (Fig. 14C, D View Figure 14 ) VP rectangular; distal margin slightly straight; straight in lateral view, with apex slightly inclined. MS C1-C4(C5) subapical long and straight (some with curved apex); MS A1-A2(A3) median long and straight, shorter than MS C. Lateral sacs long, with acuminate apex; with long T3-like microsetae. Stylus with apical region cylindrical, not swollen; with many apical small projections. Dorsal process conical, with acuminate apex, smaller than stylus. Promontory convex. - FEMALE: Measurements (n =3) DSW: 5.2-5.5; DSL: 4.5-4.7; CL: 1.7-1.8. FIVL: 11.8-12.4. ChL: 2.4-2.5. Chelicerae not swollen. Femur IV unarmed. Tarsal segmentation: (n =3) 7, 13, 10, 11.


Similar to Metasarcus kurosawai sp. nov. because ocularium unarmed, area I divided, area III with a pair of long spines (Fig. 5A View Figure 5 ) and femur IV of males slender and without rows of tubercles (Fig. 10A, B View Figure 10 ). It differs from M. kurosawai sp. nov. by gamma-P-type DSS; coxa III unarmed (Fig. 5A View Figure 5 ); male femur IV with a distal retrodorsal small apophysis (Fig. 10A, B View Figure 10 ) and penis with dorsal process and long lateral sacs (Fig. 14C, D View Figure 14 ).

Derivatio nominis.

The specific epithet, a noun in apposition, in reference to Beni Department ("El Beni"), Bolivia, Department of the type locality of the species.


(Fig. 31 View Figure 31 ) BOLIVIA. Beni. Southwest of Yucumo.

Material examined.

Type material: Holotype ♂, ' BOLIVIA, Beni, southwest of Yucumo | 15°23′S 66°59′W | 15-19/XI/1989, Coddington, Griswold, Silva, Larcher & Penaranda leg. (USNM) GoogleMaps - Paratypes 1 ♂, 3 ♀, ‘ditto’ (USNM).