Maaykuyak, González-Santillán & Prendini, 2013

González-Santillán, Edmundo & Prendini, Lorenzo, 2013, Redefinition And Generic Revision Of The North American Vaejovid Scorpion Subfamily Syntropinae Kraepelin, 1905, With Descriptions Of Six New Genera, Bulletin of the American Museum of Natural History 2013 (382), pp. 1-71 : 39-42

Maaykuyak , gen. nov.

Figures 6 , 7 , 22B , 26B ; table 1

Vejovis vittatus Williams, 1970 [= Maaykuyak vittatus (Williams, 1970) , comb. nov.], type species, here designated.

Vejovis spinigerus group (part): Gertsch and Soleglad, 1972: 605.

Vaejovis eusthenura group (part): Williams, 1980: 55; Sissom and Francke, 1985: 1; Sissom, 1991: 26; Stockwell, 1992: 408, 409; Sissom, 1993: 68; Lourenço and Sissom, 2000: 135; Sissom, 2000: 530, 532, 551; Armas and Martín-Frías, 2001: 8; McWest, 2009: 8, 48, 52, 56, 61, 64, 98, 101–103, 108, table 1 ; Ponce-Saavedra and Sissom, 2004: 541; González-Santillán, 2004: 29; Francke and Ponce-Saavedra, 2005: 67; Sissom and Hendrixson, 2005a: 131; 2005b: 33, 34; Fet et al., 2006a: fig. 17, tables 1 , 3 ; 2006b: 8; Graham and Soleglad, 2007: 9, 11, 12; Soleglad et al., 2007: 134, 135; Santibáñez-López and Sissom, 2010: 49.

Hoffmannius (part): Soleglad and Fet, 2008: 1, 26, 57, 60, 89, 91, 96, 102; Ayrey and Soleglad, 2011: 1.

ETYMOLOGY: Maaykuyak , gen. nov., is a noun in apposition, masculine in gender, meaning ‘‘god of the warriors’’ in the language of the Kiliwa people from northern Baja California.

DIAGNOSIS: Maaykuyak , gen. nov., can be separated from other genera of Syntropinae by the presence of a medium-sized oval, whitish glandular area on the dorsal medial surface of the telson vesicle in adult males, which is reduced in adult females (fig. 26B). Additional diagnostic characters of the genus are as follows: pedipalp chela manus, dm, dpl, drl, drs, and pld carinae absent (not differing in height or texture from adjacent intercarinal surfaces), dorsal intercarinal surfaces rounded, not concave, and fixed finger trichobothrium et situated between RD3 and RD4, closer to RD4; metasomal segments I– V, lateral surfaces glabrous, segment V, dm carina partially infuscated, infuscation not extending full length of segment. Maaykuyak , gen. nov., and its sister genus, Konetontli , gen. nov., each bear five fully developed retroventral macrosetae on the basitarsus of leg III (fig. 22B), compared with other genera of Syntropinae , which bear at least six.

Maaykuyak waueri , comb. nov., further resembles the species of Konetontli , gen. nov., in being one of the smallest species in the subfamily, adults measuring 15–25 mm in total length. However, these genera can be separated by the presence of a subaculear tubercle in Konetontli , gen. nov., which is absent in Maaykuyak , gen. nov. Species of Mesomexovis , gen. nov., resemble Maaykuyak , gen. nov., in the pattern of infuscation of the sclerites, but are larger and lack a glandular area on the dorsal median surface of the telson vesicle.

Maaykuyak , gen. nov., shares with Konetontli , gen. nov., Kuarapu , Syntropis , Vizcaino , gen. nov., Chihuahuanus bilineatus , comb. nov., C. coahuilae , comb. nov., and Thorellius cristimanus the presence of a secondary hook on the hemispermatophore, created by an extension of the axial carina of the distal lamina, that forms a pronounced bifurcation with the primary hook.

INCLUDED SPECIES: Maaykuyak vittatus (Williams, 1970) , comb. nov.; Maaykuyak waueri ( Gertsch and Soleglad, 1972) , comb. nov.

DISTRIBUTION: Maaykuyak , gen. nov., is endemic to Mexico (recorded from the states of Baja California Sur, Chihuahua, Coahuila, Durango, and Nuevo León) and the United States (recorded only from Texas; fig. 6). This genus has a disjunct distribution: Maaykuyak vittatus , comb. nov., occurs in the southern third of the Baja California Peninsula, whereas Maaykuyak waueri , comb. nov., inhabits the northern ranges of the Chihuahuan Desert. This distribution suggests that vicariance was promoted initially by the uplift of the Sierra Madre Occidental and subsequently by the separation of the Baja California Peninsula from the North American mainland.

NATURAL HISTORY: Maaykuyak vittatus , comb. nov., inhabits subtropical deciduous forest from sea level to 850 m altitude, whereas M. waueri , comb. nov., inhabits the Chihuahuan Desert, from 620–1922 m. Although commonly collected at night with UV light detection, both species have also been found during the day, by turning stones and disturbing leaf litter. Both species appear to prefer slightly mesic habitats, e.g., they are more abundant under forest canopy or near oases. The habitat and habitus of Maaykuyak , gen. nov., is consistent with the lapidicolous ecomorphotype ( Prendini, 2001a).

REMARKS: Both species of this genus were previously assigned to the eusthenura group of Vaejovis ( Williams, 1980; Sissom, 2000), for which Soleglad and Fet (2008) devised the name Hoffmannius , without quantitatively testing its monophyly or composition. Hoffmannius , as defined by Soleglad and Fet (2008), was consistently polyphyletic, and the two species hereby assigned to Maaykuyak , gen. nov., consistently monophyletic, in the phylogenetic analyses of González-Santillán and Prendini (in press) based on morphology and those based on morphology and DNA. Maaykuyak , gen. nov., was not related to the species Soleglad and Fet (2008) assigned to Hoffmannius , forming a monophyletic group with Konetontli , gen. nov., instead (fig. 7). The creation of a new genus for these species is based on their phylogenetic position and unique, diagnostic character combination.

MATERIAL EXAMINED: Maaykuyak vittatus (Williams, 1970) , comb. nov.: MEXICO: Baja California Sur: Municipio de Comondú: San Miguel Comondú , 5 mi. SW, 1000 ft, 2.vii.1968, S.C. Williams and M.A. Cazier, holotype ♂ ( CAS Type No. 10430) ; San Miguel Comondú, 8–16 km SW, 304 m, 3.vii.1968, S.C. Williams and M.A. Cazier, 18, 1♀ paratypes ( AMNH). Maaykuyak waueri ( Gertsch and Soleglad, 1972) , comb. nov.: MEXICO: Durango: Municipio de Tlahualilo : Hwy 49, at deviation Montes Claros–Tlahualilo de Zaragoza , 26 ° 09.242 ′ N 103 ° 31.284 ′ W, 1107 m, 6.viii.2005, O.F. Francke, W.D. Sissom, K.J. McWest, C. Lee, H. Montaño, J. Ballesteros, L. Jarvis, and C. Durán, 18, 1♀ ( AMNH). U.S.A.: Texas: Brewster Co.: Big Bend National Park : The Basin, Chisos Mountains , 28.ix.1950, holotype ♀ ( AMNH) .

Figures

Fig. 6. Map of southwestern North America, plotting known locality records for three genera in the vaejovid scorpion subfamily Syntropinae Kraepelin, 1905, based on data collected in the present study: Maaykuyak, gen. nov. (squares); Mesomexovis, gen. nov. (circles); Vizcaino, gen. nov. (triangles).

Fig. 7. Most parsimonious tree (length: 10894.593, CI: 0.190, RI: 0.628, fit: 244.08), obtained by simultaneous phylogenetic analysis of 250 qualitative and quantitative morphological characters and 4221 aligned DNA nucleotides from three mitochondrial and two nuclear gene markers, for 18 genera and 61 species in the North American vaejovid scorpion subfamily Syntropinae Kraepelin, 1905. Analyses were conducted with an implied weighting regime (k 518) that maximized average support (González-Santillán and Prendini, in press). Synapomorphies are optimized with accelerated transformation. Black bars indicate uniquely derived apomorphic states, white bars indicate parallel derivations of apomorphic states, numbers above indicate characters, and numbers below indicate states (appendix 1).

Fig. 22. Syntropinae Kraepelin, 1905, dextral leg III, basitarsus and telotarsus, ventral aspect, illustrating macrosetae and spinules. A. Kochius punctipalpi (Wood, 1863), 8 (AMNH). B. Maaykuyak waueri (Gertsch and Soleglad, 1972), comb. nov., 8 (AMNH). C. Paravaejovis pumilis (Williams, 1980), 8 (AMNH). Scale bars 5 0.5 mm.

Fig. 26. Syntropinae Kraepelin, 1905, telson, dorsal aspect illustrating glandular areas on dorsal surface (demarcated by dotted lines). A. Chihuahuanus coahuilae (Williams, 1968), comb. nov., 8 (AMNH). B. Maaykuyak waueri (Gertsch and Soleglad, 1972), comb. nov., 8 (AMNH). Scale bars 5 1 mm (A), 0.5 mm (B).