Mayazomus yaax, Monjaraz-Ruedas, Rodrigo & Francke, Oscar F., 2015

Monjaraz-Ruedas, Rodrigo & Francke, Oscar F., 2015, Taxonomic revision of the genus Mayazomus Reddell & Cokendolpher, 1995 (Schizomida: Hubbardiidae), with description of five new species from Chiapas, Mexico, Zootaxa 3915 (4), pp. 451-490 : 478-483

Mayazomus yaax , new species

Figs. 79−94 , 112 , Table 2

Type material. MEXICO: Chiapas: Heteromorphic male holotype (CNAN-T0876) [26 July 2013, O. Francke, A. Valdez, C. Santibáñez, J. Mendoza, R. Monjaraz, K. Zarate] from 1 km N from Las Delicias (15.97437ºN, 91.85234ºW, 1002 masl), Municipio La Trinitaria. Paratypes: 1 homeomorphic male and 1 female (CNAN-T0877), same data as holotype.

Etymology. The specific name is a noun in apposition, which is a Mayan word that means green, referring to the unique greenish color of the specimens.

Diagnosis. Males can be distinguished by the pedipalp trochanter having an apical triangular process less than 45º; pedipalp femoral spiniform setiferous tubercles Fv1 and Fv2 reduced and located ventrally; mesal face of the femur with two distal apophyses (FAP) ( Fig. 86 ); pedipalp tibia with two mesal apophyses, opposable to tarsus (TMA); the first apophysis submedian and long, the second small and posterior; the flagellum globose, roughly hexagonal ( Fig. 89–91 ) having a longitudinal depression and a pair of dorso-submedian swellings. Females can by distinguished by the spermathecae ( Fig. 84 ) with two pairs of lobes sub-equal in length and with the same width, fused basally and asymmetrical, with the apex of the lobes oriented internally, and the anterior branch hyaline, Vshaped. Mayazomus yaax resembles M. hoffmannae in the general morphology of the pedipalps, especially in femur shape with a more rounded femur instead of a elongated femur; but differ in the flagellum shape, which is the most peculiar characteristic of this species, having a roughly hexagonal shape and a very globose flagellum, whereas M. hoffmannae and the other known species of Mayazomus present oval or cordate shaped flagellum. Also, M. yaax presents two femoral apophyses whereas M. hoffmannae presents just one, blunt, well developed apophysis. The spermathecae of M. yaax has a peculiar shape of the lobes fused at the base Y- shaped and subequal in length with a slightly formed bulb, and it is the only species that presents an anterior branch; whereas M. hoffmannae presents lateral lobes reduced and median lobes J-shaped; the posterior branch of chitinized arch is widened at the base in M. hoffmannae and incomplete in M. yaax and with abundant fibrous tissue near gonopod area ( Fig. 84 ).

Description. Heteromorphic male (holotype): Dark greenish; flagellum and pedipalps lighter, chelicerae reddish. Prosoma: Propeltidium with two setae on anterior process and three pairs of dorsal setae; ocular spots symmetrical, roughly oval. Mesopeltidial plates 0.18 wide, 0.06 long; gap between plates 0.24. Metapeltidium 0.35 long, 0.61 wide. Anterior sternum with 10 setae, plus two sternophysial setae; posterior sternum with six setae.

Chelicerae ( Figs. 81–83 ): Movable finger: Serrula with 12 teeth. Fixed finger with 3 small teeth between 2 primary teeth. Setation: Setal group formula: 1:3, 2:6, 3:4, 4:2, 5:7, 6:1. G1 (setae group 1) with three spatulate setae, covered with small spiniform spicules starting at middle of shaft ( Fig. 83 ); G2 composed of six feathered setae, subequal in length, and shorter than movable finger length; G3 with four setae, feathered apically and smooth basally, two of them shorter, about 2/3 length of large setae; G4 consisting of two large spinose setae, smooth and thick, narrower at the tip; G5 with seven similar sized setae, feathered apically and shorter than fixed finger; G6 with one smooth seta, 2/3 of movable finger length.

Pedipalps ( Figs. 85–87 ): Robust, 2.32 times longer than propeltidium length. Trochanter short, 2.63 times longer than high; apical process triangular with an angle less than 45º, with a spiniform seta on the tip; with a row of long setae on ventral margin plus one row of setae on ectal face; mesal surface with a row of three setae near ventral margin, plus two setae near dorsal margin; with a long, apical mesal spur. Femur 1.27 times longer than high, without distal elongation; distal margin curved, ventral margin not flattened; ventral margin on ectal surface with spiniform setiferous tubercles Fv1 and Fv2 small and near each other on ventral margin ( Figs. 85, 87 ); mesal surface with two ventral plus two dorsal spiniform setae (2+2); distal margin of mesal surface with two blunt apophysis (FAP) ( Fig. 86 ) increasing in size apically, both with one spiniform seta on the tip. Patella slightly curved, open arc-shaped; with scattered setae and with two pairs of setae with a slight cuticular protuberance. Tibia expanded medially, with scattered setae; with two apophyses on ventral surface opposable to tarsus (TMA), the most distal smaller, the sub-median apophysis larger, claw-shaped. Tarsus short, 2.50 times longer than high. Claw about 0.3 times as long as dorsal length of tarsus; spurs asymmetrical, 0.05 long.

Legs: Leg I, basitarsal-telotarsal proportions: 19: 3: 4: 4: 4: 5: 10. Femur IV 2.1 times longer than wide.

Opisthosoma: Tergite I with two pairs of microsetae anteriorly plus one pair macrosetae 2+1; tergite II with three pair microsetae anteriorly plus two pairs macrosetae 3+2; tergites III–VII with one pair dorsal setae each; tergites VIII–IX with one pair dorsal and one pair lateral setae each; segments X–XI telescoped with one pair lateral setae and three pairs of ventral setae; segment XII with one dorsal, two lateral and three ventral pairs of setae, without posterodorsal process. Sternites with scattered setae; genital aperture with many microsetae.

Flagellum ( Figs. 89–91 ): dorsoventrally flattened, roughly hexagonal in shape; extremely widened, 0.96 times longer than wide, 3.40 times longer than pedicel length; with a pair of dorso-submedian protuberances separated by a median longitudinal depression which deepens at the center. Setation: Dm1 situated on the flagellar pedicel; Dm4 situated distally; Dl1, 1/3 of Vl1 setae; Dl1 anterior to Vl1; Dl3 at same level as Vl2; pair Vm2 present; seta Vm1 posterior to Vm2; Vm5 at same level as Vl1. With one pair of antero-dorsal microsetae between Dm1 and Dl1 nearest to Dl1; one pair of antero-lateral microsetae on flagellar pedicel near to Dm1, and one pair of irregular clumps between Vl1 and Vl2, each composed of 5 microsetae.

Female (paratype): Similar to the heteromorphic holotype male, except in pedipalp development, 1.80 times longer than propeltidium length, female pedipalps are very similar to homeomorphic males except for the lack of femoral apophysis development ( Fig. 88 ). Other differences: Propeltidium shorter than male ( Table 2 ), general setation as on male, except for the presence of an extra seta on the anterior process (row of three setae). Anterior sternum with 11 setae, plus two sternophysial setae. Flagellum with three annuli ( Figs. 92–94 ). Setation: seta Dl1 reduced (1/3 of Vl1 length, as on male) and at same level as Vl1; Dl3 posterior to Vl2; Vm2 present and reduced; seta Vm1 at the same level as Vm2. Segment III with one lateral pair of microsetae near to Vm4. Segment IV with one pair of distolateral microsetae near Vl2. Spermathecae ( Fig. 84 ), with 4 lobes subequal in length; with irregular margins, one of the lateral lobes with an internal and apical ramification; the lateral lobes fused at the base with the median lobes forming a Y-shape; median lobes with a slightly formed bulb; both pairs with duct openings. Gonopod long and wide, with many tissue fibers around the chitinized arch. Chitinized arch V-shaped, posterior branch wide at base and incomplete, with irregular margins, lateral tip curved, internal angle rounded; with a slightly sclerotized anterior branch V-shaped, without anteromedian projection, and anteromedian notch rounded. Chelicera: serrula with 13 teeth. Fixed finger with 4 smaller teeth between 2 primary teeth. Setae 1:3, 2:5, 3:4, 4:2, 5:7, 6:1.

Variation. The homeomorphic male differs from the heteromorphic male mainly in the pedipalp size (total length of the pedipalp in heteromorphic male 2.32, and in homeomorphic male1.83 times the length of the propeltidium), and body size (total length, homeomorphic: 2.92, heteromorphic: 3.32 mm); the trochanter of the homeomorphic male presents the apical process less pronounced, similar to the apical process of the female; the femur is wider and longer (heteromorphic 1.27, homeomorphic 1.65 times longer than wide); the femoral apophysis is weakly developed in homeomorphic males but the two apophyses are present; the curvature of the patella in homeomorphic males is slightly pronounced, and the ventral margin flattening is absent; the tibia of the homeomorphic males lacks the two apophyses opposable to tarsus, which are present in the heteromorphic males. Female cheliceral movable finger with more small teeth on serrula than on male (13 versus 12); setal group G2, female has six setae and male has five.

Distribution. This species is known only from the type locality ( Fig. 112 ).

Natural history. The specimens were collected under rocks in a preserved area of a deciduous forest

Figures

FIGURE 112. Distribution map of the known species of the genus Mayazomus, showing the type localities of the five new species: M. tzotzil, M. aluxe, M. kaamuul, M. yaax and M. loobil

FIGURES 79, 80. Mayazomus yaax new species. Male holotype. Habitus: 79. Dorsal view. Female paratype. Habitus: 80. Dorsal view. Scale bar = 2 mm.

FIGURES 81 – 84. Mayazomus yaax new species. Male. Chelicera (81 – 83): 81, mesal view. 82, fixed finger. 83, movable finger. Female. Spermathecae: 84, dorsal view. Scale bar (Fig. 84) = 0.05 mm.

FIGURES 85 – 88. Mayazomus yaax new species. Heteromorphic male. Pedipalp: 85, ectal view. 86, mesal view. Homeomorphic male. Pedipalp: 87, ectal view. Female. Pedipalp: 88, ectal view. Scale bars = 0.5 mm.

FIGURES 89 – 94. Mayazomus yaax new species. Male holotype. Flagellum (89 – 91): 89, dorsal view. 90, ventral view. 91, lateral view. Female. Flagellum (92 – 94): 92, dorsal view. 93, ventral view. 94, lateral view. Scale bars = 0.2 mm.