Metabalta polyhastata ( Hara, 2016 ) Acosta, 2020

Acosta, Luis E., 2020, Qorimayus, a new genus of relictual, high-altitude harvestmen from western Argentina (Arachnida, Opiliones, Gonyleptidae) reveals trans-Andean phylogenetic links, Zootaxa 4722 (2), pp. 129-156 : 152

Metabalta polyhastata ( Hara, 2016) comb. nov.

Nanophareus polyhastatus Hara, 2016: 117 ; Pérez-Schultheiss et al., 2019: 10. urn:lsid:zoobank.org:act:364BA304-56DD-4C73-9BF3-FA652B038A46

The results of the cladistic analysis ( Fig. 1 ) demonstrated that Nanophareus polyhastatus Hara, 2016 forms a wellsupported clade with species of Metabalta . This relationship is underpinned α-taxonomically too, as evidenced by a close examination of the original description and illustrations of N. polyhastatus : the exomorphological and genital features of this species ( Hara, 2016) best match the character states present in Metabalta , as defined in Table 8 . For example, fig. 6A by Hara (2016) clearly displays pedipalp coxae with ‘normal’ appearance, i.e., not elongated as in Nanophareus . In addition, N. polyhastatus has a ‘normal’ development of basichelicerite and pedipap femur, and the retrolateral apical-subapical spines on tibia are placed in a bifid basal socket, not as large and furcate-tipped as in Nanophareus ( Table 8 , chars. b, d, h). Several genital characters support the transfer of N. polyhastatus into Metabalta , like the sigmoid curvature of stylus, its orientation and apical narrowing, and the apical end of VPS ( Table 8 , chars. o, p, r, s); drawings of Hara (2016) are not detailed enough to see if also char. t (subapical spines on VPS shaft) applies. Based on this evidence, I hereby formally propose the new combination Metabalta polyhastata ( Hara, 2016) comb. nov. (the original spelling polyhastatus changed to polyhastata to ensure the agreement in grammatical gender with the genus name Metabalta ).

Aside, Pérez-Schultheiss et al. (2019) suggested that N. polyhastatus and Metabalta albipes Mello-Leitão, 1931 might prove to be the same. Although the latter species has no original figure available for a comparison, that of Metabalta porteri Mello-Leitão, 1936 (currently under synonymy of M. albipes , after Ringuelet 1959) looks identical to M. polyhastata , as described and drawn by Hara (2016); key similarities refer to the general apophysis pattern on femur IV, and the shape (and thickness) of apophysis of coxa IV. Until the relevant types are studied I prefer not to formalize this presumed specific synonymy. It should be noted that M. polyhastata was included by Hara (2016) in his cladistic analysis of Nanophareus , but resulted in an internal position in the genus.

Additional material examined. Metabalta efformata : Chile: Sierra de Chillán , 2 ♂ syntypes ( SMF RII 952 ) ; Metabalta geniculata : Chile: Valparaíso, 1 ♂, 1 ♀ syntypes ( SMF RII 951 ) ; Nanophareus palpalis : ‘ Chile’ , 1 ♂ lectotype, 1 ♂, 2 ♀ paralectotypes (designated by Hara et al. 2012; SMF 986 /1); Nanophareus bosqenublado : Chile: Los Molles, elev. 2 m, under succulent rock cover along coast, 9 Jan. 1985, N.I. Platnick & O.F. Francke ( AMNH) .

Figures

FIGURE 1. Cladistic relationships of Qorimayus gen. nov.: single most parsimonious tree obtained with implied weights (IW), k=6 (Ci: 0.37, Ri: 0.60, tree length: 376 steps). Character optimization: solid circles depict non-homoplasious states, open circles are homoplasious states. Small numbers on a circle indicate the character number (above the circle) and its state (below); larger numbers under relevant branches display values of bootstrap, jackknife and symmetric resample (B-J-SR), high support values in bold. Abbreviations for major clades (underlined): G: Gonyleptidae; PsG: Pachyloides-group; PG: Pachylus-group; PG+Eu: Pachylus-group plus Eusarcus spp.; MG: Metabalta-group; M+Na(+): Metabalta+Na(+); M: genus Metabalta; Na(+): Nanophareus, plus N+T; Na: genus Nanophareus; e-s: “eyes-separate” clade.