Yekuana, Botero-Trujillo & Moreno-González & Prendini, 2024

3.2.3. Yekuana , gen. n.

urn:lsid:zoobank.org:act:68003E41-7E5F-4829-8884-B88080CCAE31

Figure 1 View Figure 1 , Figure 2 View Figure 2 , Figure 3B View Figure 3 , Figure 4B,D View Figure 4 , Figure 5B,D View Figure 5 , Figure 6C,D View Figure 6 , Figure 7B,D,F View Figure 7 , Figure 8B,D,F View Figure 8 , Figure 9B View Figure 9 , Figure 10B,D View Figure 10 , Figure 11B,D View Figure 11 , Figure 12D–F View Figure 12 , Figures 13C View Figure 13 , 14 View Figure 14 , 16F View Figure 16 and 17C View Figure 17 and Table 1 View Table 1

Type Species. Yekuana wanadi , sp. n., here designated.

Diagnosis. Yekuana may be separated from the other Neotropical genera of Hypoctoninae , i.e., Wounaan , Thelyphonellus , and Ravilops , as follows. The anterior margin of the carapace ( ♂) is markedly pointed in Yekuana ( Figure 4 B View Figure 4 ), whereas it is slightly pointed in Thelyphonellus (at least T. amazonicus and T. aff. ruschii ) and slightly pointed or semi-elliptical in Wounaan ( Figure 4 A View Figure 4 ). The fovea (at least in the ♂) is elongated, aligned with the trochanter of leg III and slightly extending beyond it anteriorly, and deep in Yekuana ( Figure 4 B View Figure 4 ) but short, aligned with the trochanter of leg III, and very shallow (barely visible) to moderately shallow (distinct) in Ravilops (at least R. wetherbeei ) and Wounaan (e.g., Figure 4 A View Figure 4 ). The carapace of Yekuana does not possess a longitudinal raised surface anteromedially ( Figure 4 B View Figure 4 ), as in Wounaan ( Figure 4 A View Figure 4 ). The median sternum (mesosternum) of Yekuana is markedly sclerotized and pigmented across its entirety ( Figures 4 D View Figure 4 and 16 F View Figure 16 ), whereas the mesosternum of Thelyphonellus (at least T. amazonicus and T. aff. ruschii ) ( Figure 16 C View Figure 16 ) and Wounaan ( Figure 16 D, E View Figure 16 ) has two markedly-sclerotized and pigmented areas, anteriorly and posteriorly, separated by a pale depigmented area medially, and that of Ravilops (at least R. wetherbeei ) ( Figure 16 B View Figure 16 ) is only markedly sclerotized and pigmented anteriorly, with the rest of the mesosternum being pale and depigmented.

Several differences in pedipalp morphology exist between Yekuana and the other genera. The cuticle of the pedipalp dorsal and retrolateral surfaces is entirely smooth, except for the chela fingers, which are minutely reticulate (visible at great magnification) in Yekuana , whereas it is entirely smooth in Thelyphonellus (at least T. amazonicus and T. aff. ruschii ) and predominantly smooth but with fine yet distinct reticulation (visible at great magnification) in Wounaan . The principal (fourth) prodorsal tubercle of the pedipalp trochanter ( ♂) is larger than the other tubercles in Yekuana ( Figure 7 B View Figure 7 ), whereas the tubercle is similar to or shorter than the adjacent (third and fifth) tubercles in Wounaan ( Figure 7 A View Figure 7 ). The proventral distal tubercle of the trochanter ( ♂) is moderately enlarged (about as broad as long) or slightly enlarged (slightly longer than broad) in Yekuana but markedly enlarged (much longer than broad) in Ravilops and small and not enlarged in Thelyphonellus (at least T. amazonicus and T. aff. ruschii ). The proventral tubercle of the pedipalp femur ( ♂) is moderate and subspiniform in Yekuana but large and spiniform in Ravilops (at least R. wetherbeei ) and Wounaan ( Figure 7 C View Figure 7 ). The pedipalp patellar apophysis ( ♂) is moderate, its length slightly less than the patella width, in Yekuana ( Figure 7 F View Figure 7 ) but long, its length greater than the patella width, in Wounaan ( Figure 7 E View Figure 7 ). The prolateral (anterior) margin of the patellar apophysis ( ♂) bears a row of 3–5 granules (not including the apex) in Yekuana ( Figure 7 F View Figure 7 ) compared to a row of 6–9 granules in Ravilops and 7–9 granules in Wounaan ( Figure 7 E View Figure 7 ). The patella proventral distal tubercle ( ♂) is small or obsolete in Yekuana ( Figure 8 F View Figure 8 ), whereas it is moderate and distinct in Ravilops (at least R. wetherbeei ) and Wounaan (e.g., Figure 8 E View Figure 8 ). The pedipalp tibia (manus) ( ♂) is unmodified and not dorsoventrally expanded (barrel-shaped) in Yekuana ( Figure 8 B, D View Figure 8 and Figure 17 C View Figure 17 ) but markedly expanded dorsoventrally (subcircular in lateral aspect, not barrel-shaped) in Wounaan ( Figure 8 A, C View Figure 8 and Figure 17 B View Figure 17 ). The proventral distal tubercle of the pedipalp tibia (manus) ( ♂) is small and rounded in Yekuana ( Figure 8 F View Figure 8 ) but large and spiniform in Ravilops and Wounaan (e.g., Figure 8 C, E View Figure 8 ). The ventral part of the retrolateral surface of the tibia (manus) (i.e., the retrolateral surface aligned with the movable finger) ( ♂) is unmodified and slightly convex, like the rest of the retrolateral surface, in Yekuana ( Figure 8 B, D View Figure 8 and Figure 17 C View Figure 17 ), whereas it is planar to noticeably concave in Wounaan ( Figure 8 A, C View Figure 8 and Figure 17 B View Figure 17 ). The ventral row of denticles on the pedipalp fixed (tibial) finger ( ♂) is linear in retrolateral aspect in Yekuana ( Figures 8 B View Figure 8 and 17 C View Figure 17 ) but slightly to markedly sinuous in retrolateral aspect in Wounaan ( Figures 8 A View Figure 8 and 17 B View Figure 17 ). The basal lobe of the dorsal row of denticles on the pedipalp movable finger (tarsus) ( ♂) is pronounced in Yekuana ( Figures 8 B View Figure 8 and 17 C View Figure 17 ) but obsolete or absent in Ravilops , Thelyphonellus (at least T. amazonicus and T. aff. ruschii ), and Wounaan (e.g., Figures 8 A View Figure 8 and 17 A, B View Figure 17 ). The dorsal row of denticles on the tarsus ( ♂) lacks a distal lobe in Yekuana ( Figures 8 B View Figure 8 and 17 C View Figure 17 ) that is present (though small or shallow) in Ravilops (at least R. wetherbeei ) and Wounaan (e.g., Figures 8 A View Figure 8 and 17 B View Figure 17 ).

There are also several differences in the opisthosomal morphology between Yekuana and the other genera. Tergite I is entire, II and III each exhibit a distinct median longitudinal suture (complete), IV and to a lesser extent V only exhibit a longitudinal suture anteriorly (obsolete in both), and the other tergites are undivided in Yekuana ( ♂) ( Figure 5 B View Figure 5 ), whereas tergite I is partially divided (posteriorly only) and terminating in a triangular hyaline area, II and III each exhibit a distinct median longitudinal suture (complete), IV and to a lesser extent V only exhibit a longitudinal suture anteriorly (obsolete in both), and the other tergites are undivided in Ravilops (at least R. wetherbeei ) ( ♂); tergite I is entire, II and III each exhibit a distinct median longitudinal suture (complete), IV and to lesser extent V–VIII only exhibit a longitudinal suture anteriorly (obsolete in all but IV), and the other tergites are undivided in Thelyphonellus (at least T. amazonicus and T. aff. ruschii ) ( ♂); and tergite I is entire, II–IV each exhibit a distinct median longitudinal suture (complete in II and III and only present anteriorly in IV), and the other tergites are undivided in Wounaan ( ♂) ( Figure 5 A View Figure 5 ). The posterior margin of sternite II (genital) ( ♂) is moderately expanded (enlarged and lobate) and semicircular along the entire margin in Yekuana ( Figures 5 D View Figure 5 and 11 B View Figure 11 ) but moderately expanded (enlarged and lobate) and sinuous posteromedially in Wounaan and Ravilops (e.g., Figures 5 C View Figure 5 and 11 A View Figure 11 ) and markedly expanded (enlarged and lobate) and semicircular along the entire margin (significantly larger than in ♀) in Thelyphonellus (at least T. amazonicus and T. aff. ruschii ). The opisthosomal segment XII (distal segment of pygidium) of Yekuana lacks dorsolateral ommatoids ( Figure 12 D, E View Figure 12 ), unlike Ravilops and Wounaan , in which a pair of well-developed, medium-sized ommatoids is present (e.g., Figure 12 A, B View Figure 12 ).

Etymology. The new genus is named in honor of the Ye’kuana, an indigenous tribe inhabiting the tropical forests of the Orinoco Basin in southern Venezuela (Bolívar State) and a small part of northern Brazil. The name is feminine in gender.

Included Species. Yekuana , gen. n. is hereby created to accommodate two species, one of which was formerly assigned to Thelyponellus: Yekuana venezolensis (Haupt, 2009) , comb. n. and Yekuana wanadi , sp. n.

An unidentified, adult male of Yekuana from Sifontes, a municipality in the Bolívar State of Venezuela, was examined during the study. The specimen is significantly smaller than the holotype of Y. venezolensis and resembles the holotype of Y. wanadi in several respects, including its smaller size (although slightly larger than the holotype of Y. wanadi ) and similar shape of the anterior margin of the carapace and development of the pedipalp tubercles. Unfortunately, the specimen lacks the flagellum (apparently severed when the specimen was alive based on the presence of a scar), which could have enabled its identification to species, given the marked differences in flagellar morphology between the two species of Yekuana . The locality at which the unidentified specimen was collected is near the type locality of Y. venezolensis and far from that of Y. wanadi .

Distribution. Known only from the state of Bolívar, Venezuela ( Figure 2 View Figure 2 ).