Taxonomía y sistemática

 

A new species of Centruroides (Scorpiones: Buthidae) from the northern mountain range of Oaxaca, Mexico

 

Una especie nueva de Centruroides (Scorpiones: Buthidae) de la sierra norte de Oaxaca, México

 

Carlos E. Santibáñez–López^1,* and Javier Ponce–Saavedra²

 

¹ Colección Nacional de Arácnidos, Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México, Apartado postal 70–153, 04510 México D.F., México.

² Laboratorio de Entomología Biól. Sócrates Cisneros Paz, Facultad de Biología, Universidad Michoacana de San Nicolás de Hidalgo, Edificio B–4 2° Piso, Ciudad Universitaria, 58060 Morelia, Michoacán, México.

 

*Correspondencia:
ironc81@hotmail.com

 

Recibido: 16 mayo 2008
Aceptado: 02 octubre 2008

 

Abstract

Centruroides serrano sp. nov. from the Sierra Juárez of Oaxaca (Villa Alta District) is described. This is the eleventh species of the genus reported from Oaxaca and the first one reported from this area. It occurs from 500 m to 1 500 m. It is compared to C. baergi Hoffmann, 1932, C. nigrovariatus Pocock, 1898 and C. hoffmanni Armas, 1996 due to its overall similarity. To separate these 4 species, a principal component analysis was conducted. A list of the species of this genus from Oaxaca is provided.

Key words: scorpions, diversity, principal components analysis, multiple correlation analysis, one way analysis of variance.

 

Resumen

Se describe Centruroides serrano sp. nov. de la sierra Juárez de Oaxaca (distrito de Villa Alta). Es la onceava especie del género reportada para Oaxaca y la primera reportada para el área. Se distribuye en elevaciones desde los 500 a los 1 500 m. Se compara con C. baergi Hoffmann, 1932, C. nigrovariatus Pocock, 1898 y C. hoffmanni Armas, 1996 por su parecido morfológico. Para separar estas 4 especies, se llevó a cabo un análisis de componentes principales. Finalmente, se incluye una lista de las especies del género presentes en Oaxaca.

Palabras clave: alacranes, diversidad, análisis de componentes principales, correlación múltiple, análisis de varianza de una vía.

 

Introduction

Mexico harbors one of the world's largest scorpiofaunas, with more than 200 species and subspecies in 7 families and 24 genera (Fet et al., 2000; Lourenço and Sissom, 2000; Sissom and Hendrixson, 2006). The family Buthidae is represented in the country by 2 genera: Tityopsis Armas, 1974, with 1 species in the Isthmus of Tehuantepec (T. aliciae Armas and Martín–Frías, 1998); and Centruroides Marx, 1890, with 30 species distributed throughout the country (Lourenço and Sissom, 2000; Ponce and Barajas, 2005; Armas et al., 2003).

García–Mendoza et al. (2004) consider the state of Oaxaca as one of the most biodiverse in México. The Sierra Juárez (from now on referred to as the "Northern mountain range") is one of the most important regions of the state for conservation. It has been poorly studied from the point of view of its arthropods, although it has been considered an important area for conservation due to its high plant endemism (Lorence y García–Mendoza, 1989). There are no published records of any species of Centruroides for this area. Currently the scorpiofauna of the area is being studied as part of the master's degree research of the senior author. In the present contribution, a new species of Centruroides is described from the District of Villa Alta.

Centruroides is one of the best studied scorpion genera in the country due to the high toxicity of some species, but still remains poorly sampled (Ponce–Saavedra and Francke, 2004) and the status of several species is unclear. It was divided into 3 major groups by Hoffmann (1932), modified into 4 major groups by González–Santillán (2001) and subsequently accepted by Ponce and Barajas (2005): a) C. gracilis species group: species with 9 denticle rows on the fingers of the pedipalp chelae (see Capes, 2002); b) C. thorelli species group: small species with variegated fuscous patterns not consisting of 2 longitudinal rows dorsally along the opisthosoma; c) C. bertholdii species group: species with 8 denticle rows on the fingers of the pedipalp chelae (this group is not well characterized and a better delimitation is required); and d) the striped ones: all the species with 8 denticle rows in the fingers of the pedipalp chela and with 2 dark longitudinal bands along the mesosoma with 1 yellow band between them. The "striped" group is divided into 2 subgroups: the C. elegans–limpidus subgroup (species with longitudinal bands along the carapace; 2 longitudinal bands along the mesosoma with spots on the pretergite and the postergite) and the C. infamatus–nigrovariatus (C. suffusus–infamatus sensu Ponce and B araj as, 2005) subgroup with variegated fuscous pattern in the carapace and without the longitudinal bands along it, and 2 longitudinal bands along the mesosoma with a well defined spot on the pretergites and another on the median portion of the postergites united by a diffused pigmentation.

Oaxaca is the state with the highest number of species of Centruroides in the country, with 10 described species (Table 1) (Beutelspacher, 2000; Fet et al., 2000; Armas et al., 2003; Santibáñez–López et al., 2007). Although Fet et al. (2000) reported C. elegans Thorell, 1876 on the coast of Oaxaca (a misidentification; it corresponds to C. meisei Hoffmann, 1938, see Armas and Martín–Frías, 1998) and there have been some records of C. limpidus Karsch, 1879 along the boundaries of the state with Guerrero and Puebla, there are no other records of medically important species in Oaxaca. Thus, additional collections are necessary.

The taxonomy of the "striped" group in the genus is complicated because it is largely based on morphometric characters and coloration patterns, which are characters that show high intraspecific variation; according to Ponce (2003) this often leads to misidentification. Ponce et al. (1999) and Ponce and Barajas (2005) indicate that the morphometric variables can be tested in a multivariate analysis and then it is possible to select the variables with the lowest intraspecific variability and the highest interspecific variability for a numerical taxonomy approach to this complex problem. These multivariate techniques have been used to separate sympatric species of the genus Euscorpius Thorell, 1876 (Euscorpidae) in Italy (Vignoli et al., 2005), species of the genus Centruroides in Michoacán, México (Ponce and Francke, 2004), and to show intraspecific and interspecific variability within the genus Mesobuthus Vachon, 1950 (Buthidae) in Turkey (Karatas, 2007). A multivariate analysis was conducted to strengthen the separation of the new species from the northern mountain range of Oaxaca from its close relatives.

 

Material and methods

Fieldwork. A trip to the District of Villa Alta, in the northern mountain range in Oaxaca, Mexico in June–July 2007, allowed us to collect scorpions under rocks and other objects on the ground during daylight, and at night using UV light detection (Sissom et al., 1990). A preliminary examination of the specimens indicated strong similarities with C. nigrovariatus, C. baergi and C. hoffmanni. These 3 taxa plus the unidentified material from the Villa Alta district were included in the analysis. Additional material was obtained from other collection trips (see taxonomic summary).

Statistical analysis. A statistical analysis was conducted to obtain a better resolution among the morphometric variables and their importance as diagnostic characters. First, we selected 31 morphometric variables and 15 morphometric ratios to test their usefulness as characters for multivariate analysis. This dataset was tested with multiple correlation analysis to select the variables with the lowest redundancy values. With the reduced dataset, a principal component analysis (PCA) was carried out to evaluate the variables with the highest contribution to the explained variance contained in the 3 principal components. This procedure was repeated until we found a group of characters with high interspecific variation and the lowest possible intraspecific variation. Finally, the variables were used to perform one way analysis of variance (ANOVA) followed by the Tukey–Kramer procedure to determine which pairs of means had statistically significant differences. All analyses were performed with the JMP v. 6.0 statistical software (SAS Institute).

Five males and 5 females of each species were measured. A Student's t–test was undertaken after the ANOVA because 2 species remained with unclear status: C. baergi and C. serrano.

Measurements and counts. Carapace length, mesosoma length, pectinal tooth count (right pectine), pedipalp chelae: fixed finger length, fixed finger external accessory denticle count, fixed finger internal accessory denticle count, movable finger length, movable finger external accessory denticle count, movable finger internal accessory denticle count, chela length, femur length, patella length, patella width, subaculear tubercle (multistate character: 0=obsolete or weak, 1=moderate developed and 2=strong and well developed), metasoma length, segment I length, segment I width, segment II length, segment II width, segment III length, segment III width, segment IV length, segment IV width, segment V length, segment V width, segment V depth, vesicle length, vesicle width, vesicle depth, aculeus length, total length.

Morphometric ratios. Total length / metasoma length, metasoma length / carapace length, carapace length / metasomal segment V length, carapace length / movable finger length, patella length / width, vesicle length / width, vesicle length / aculeus length, fixed finger length / movable finger length, aculeus length / total length, movable finger length / patella length, patella length / vesicle length, carapace length / chela length, movable finger length / chela length, patella length / metasomal segment V depth, metasomal segment V length / metasomal segment I length.

Description. Nomenclature and measurements follow Stahnke (1970), except for trichobotrial terminology after Vachon (1974) and metasomal carinal terminology after Francke (1977). Measurements were taken with an ocular micrometer calibrated at 10X and are given in millimeters. The picture was obtained with a Nixon Coolpix S10 VR camera supported on a Nikon SMZ800 stereoscope. Abbreviations for depositories: AMNH— American Museum of Natural History, New York, USA; and CNAN—Colección Nacional de Arácnidos, Instituto de Biología, Universidad Nacional Autónoma de México, Mexico, D. F.

 

Results

In the PCA, the cumulative variance for the first 3 principal components (70%) split the species into 2 groups: small species (C. nigrovariatus and C. hoffmanni) and large species (C. baergi and the Villa Alta population). We eliminated the 2 smaller species from the subsequent analyses because they are clearly distinguished by size and other characters (see comparative description for full details). With the large–size group, we ran the multiple correlation procedure and 26 characters were eliminated due their high correlation levels, and then a PCA was performed. The variance explained by the first 3 principal components was lower (66.7%) than in the first analysis, but a better separation was observed. A third multiple correlation analysis was made and 9 additional characters were eliminated from the dataset, and a new PCA was performed. From this analysis, the first component separated the 2 species and the explained variance was better than in the previous (73.63%). From this final PCA, we found 3 variables (the fixed finger internal accessory denticle count, the movable finger external accessory denticle count, and the vesicle width) with the highest eigenvalues and the highest contribution to the explained variation. Also the state of the subaculear tubercle is an important character to separate both species. None of the 15 ratios included in the analysis had high values in the first principal component. However, in the second principal component there are 3 ratios: the carapace length / segment V length; the vesicle length / aculeus length and the movable finger length / patella length which contribute significantly to the variation under analysis.

The ANOVA allowed us to select 3 characters with statistically significant differences (p<0.05) (all morphometric, see Appendix 1 and comparative description) that separate the 2 large–sized species. The Student's t–test allowed the separation of these 2 species from each other (Table 2). Also, this analysis provided 2 morphometric ratios with statistically significant differences and they characterize the sexual dimorphism in these 2 species (see remarks).

Centruroides serrano sp. nov. (Figs. 1–5, 9)

Diagnosis. Scorpions of moderate size, adults 51–59 mm long (x=56.4 mm +/–S.D.= 2.88, n=10) belonging to the C. infamatus – nigrovariatus sungroup (within the striped group). Carapace with diffuse fuscosity but without distinct longitudinal black color bands along it. Two pigmented rows along tergites conformed by a dark spot on postergite only. Pectinal tooth count in males 23 to 27) mean=24+/–S.D.=1.12; n=20) and in females 20 to 23 (mean=24+/–S.D.=1.04; n=20). Internal accesory denticle count of movable finger 30 to 38 (only adults; mean=38+/–S.D.=4.67; n=24) and external accesory denticle count of movable finger 31 to 46 (also only adults; mean=39+/–S.D.=3.9; n=24). Subaculear tooth well developed and it points towars the middle of aculeus. Vesicle 1.5 times deeper than wide.

Male holotype (Figs. 1–2; measurements in Table 3). Coloration: Base color pale yellow brown above with faint to moderate dusky markings on chelicerae, pedipalps, legs and tergites. Coloration fairly uniform except as follows: coxosternal region light orange, pectines very pale yellow, metasomal segment V and telson dark orange to reddish; cheliceral teeth and tip of aculeus dark reddish brown. Granulation on the pedipalp fingers dark red.

Prosoma: carapace coarsely granulose (Fig. 3); anterior median furrow moderately deep; posterior median furrow shallow anteriorly, deeper posteriorly; ocular tubercle dark, granulose. Lateral margins finely serrate. Carapacial carinae inconspicuous, indicated by small granules. Anterior median notch moderately deep.

Mesosoma: two pigmented rows along the tergites formed by a dark spot only on postergite. Lateral margin of tergites I–VI with a dark serrate carina. Pretergites and postergites separated by a feebly granulose carina. Postergite posterior margin with moderate size, sparse granules. Tergal median carinae on I–VI weak to obsolete on anterior portion; moderate on posterior portion. Tergite VII: median carina moderately granulose; submedian carinae moderate, granulose; lateral carinae moderate, serrate. Sternites III–VI smooth, VII with submedian carinae weak, weakly granulose; lateral carinae moderate, serrate. Pectinal basal piece twice wider than long; posterior margin slightly rounded. Pectinal tooth count 23–23.

Metasoma: dorsolateral carinae: on I–III moderate, serrate; on IV strong, serrate. Lateral supramedian carinae: on I–III strong, serrate; on IV moderate, serrate. Lateral inframedian carinae: on I strong, serrate; on II–IV vestigial. Ventrolateral carinae: on I moderate, feebly crenate to serrate; on II–IV moderate, serrate. Ventral submedian carinae: on I–IV moderate, crenate. Intercarinal spaces shagreened. Segment V (Fig. 4): Dorsolateral carinae weak, sparsely granulose. Ventrolateral carinae moderate, granulose. Ventromedian carina weak to vestigial. Intercarinal spaces shagreened. Vesicle of telson elongate oval in shape. Ventral aspect with row of small granules leading to the subaculear tooth; subaculear tooth well developed, conical, its point towards middle portion of aculeus.

Pedipalp (Figs. 5–7): orthobothriotaxy type "A" (Vachon, 1974); femur with alpha configuration of dorsal trichobotria (Vachon, 1975). Femur. Dorsointernal, dorsoexternal and ventroexternal carinae strong, serrate. Ventrointernal carina moderate to weak, sparsely granulose. Dorsal face moderately granulose. Patella. Dorsointernal carina moderate, serrate. Dorsomedial and dorsoexternal carinae moderate to weak, feebly crenate. Ventrointernal carina weak, weakly granulose. Internal face with 4 large subconical granules. Chela. Dorsomarginal carina weak to moderate, feebly crenate, dorsal secondary carina weak, granulose. Digital carina weak, smooth, other carinae weak, smooth. Right chela fixed finger with 8 oblique rows of granules flanked by 30 inner accessory denticles and 37 outer accessory denticles (right pedipalp chela). Right chela movable finger with 8 oblique rows of denticles flanked by 35 internal accessory denticles and 45 outer accessory denticles.

Male intraspecific variation. Pectinal tooth counts (n=20 pectines): 23 teeth (6 pectines), 24 (9), 25 (3), 26 (1) and 27 (1). Fixed finger outer accessory denticles (both pedipalp chelae) (n=20): 25 denticles (1 finger), 26 (1), 28 (3), 29 (4), 30 (3), 31 (2), 32 (2), 33 (1), 34 (1) and 35 (1). Fixed finger inner accessory denticles (both pedipalp chelae) (n=20): 32 denticles (1 finger), 33 (2), 34 (1), 35 (5), 36 (4), 37 (2), 38 (1), 39 (1), 40 (2) and 41 (1). Movable finger outer accessory denticles (both pedipalp chelae) (n=20): 31 dentices (1 finger), 32 (1), 33 (1), 37 (2), 38 (3), 39 (4), 41 (1), 42 (1), 43 (1), 44 (1), 45 (2), 46 (1) and 52 (1). Movable finger inner accessory denticles (both pedipalp chelae) (n=20): 30 denticles (1 finger), 31 (1), 32 (3), 33 (2), 34 (4), 35 (3), 36 (2), 37 (1) and 38 (3).

Female: Carapace longer than male; basal pectinal piece with a shallow depression in the middle portion, which is absent on males (Fig. 9): anterior margin straight; posterior margin weakly bilobed; 22–22 pectinal teeth; inner accessory denticles on the fixed finger 35; on movable finger 36; outer accessory denticles on fixed finger 37; on movable finger 41.

Female intraspecific variation. Pectinal tooth counts (n=19): 20 teeth (4 pectines), 21 (4), 22 (7) and 23 (4).

 

Taxonomic summary

Type data. Holotype male from 6 km S San Andrés Zoolaga, district of Villa Alta, Oaxaca, Mexico (1119 m) 21/07/2007, N 17° 15.472'; W 96° 14.393', cols. O. Francke, A. Ballesteros, H. Montaño, C. Santibáñez y A. Valdez, CNAN–T0348. Paratype female (CNAN–T0349) and paratype male (AMNH) from San Melchor Betaza, Villa Alta, Oaxaca, México (1 415 m) 18/12/2006 N 17° 15.061' W 96° 09.188', cols. C. Santibáñez and H. Jara.

Other material (Fig. 13). Centruroides serrano sp. nov. 1 , 6 (CNAN) 1 km NE de San Andrés Yaa, Villa Alta, Oaxaca, México (1 506 m) 21/07/2007, N 17° 18.086' W 96° 09.180', cols. O. Francke, A. Ballesteros, H. Montaño, C. Santibáñez and A. Valdez. 1 (CNAN) 6 km S de San Juan Tabaa, Villa Alta, Oaxaca, México (1 734 m) 21/07/2007, N 17° 16.697' W 96° 13.481', cols. O. Francke, A. Ballesteros, H. Montaño, C. Santibáñez and A. Valdez. , 2 1 (CNAN) San Francisco Cajonos, Villa Alta, Oaxaca, México (1 678 m) 20/06/2007, N 17° 10.125' W 96° 14.671', cols. A. Valdez and C. Santibáñez. 5, 1 (CNAN) Km 101 carretera Díaz Ordaz–Villa Alta, Villa Alta, Oaxaca, México (992 m) 21/06/2007 N 17° 13.463' W 96° 09.124', cols. A. Valdez and C. Santibáñez.

Centruroides nigrovariatus. 1, 1 (CNAN) Camino a Santa Catarina Ixtepeji, Ixtlán de Juárez, Oaxaca, México (1 951 m) 17/06/2007, N 17° 16.778' W 96° 32.686', cols. A. Valdez and C. Santibáñez. 1, 1 (CNAN) Km 9 carretera Díaz Ordaz – San Antonio Cuajimoloyas, Ixtlán de Juárez, Oaxaca, México (2 363 m) 01/04/2007 N 17° 02.394' W 96° 28.267', cols. C. Santibáñez and H. Jara. 2 , 3 (CNAN) Campamento Tatachinto, Santiago Xiacuí, Ixtlán de Juárez, Oaxaca, México (2 278 m) 13/11/2005 N 17° 17.244' W 96° 25.069', cols. O. Francke, M. Córdoba, A. Jaimes, G. Montiel and C. Santibáñez. 5subadult, 5 (CNAN) Km 45.8 carretera federal 175 tramo Oaxaca–Ixtlán de Juárez, Oaxaca, México (2 003 m) 14–15/06/07 N 17° 17.834' W 96° 32.582', cols. A. Valdez and C. Santibáñez.

Centruroides baergi. 1 subadult (CNAN) Paraje 5. Mezquites 8 km S Zinacatepec, Puebla, México (1075 m) 08/11/2005, N 18° 18.147' W 97° 12.918', cols. O. Francke, M. Córdoba, A. Jaimes and G. Montiel. 2, 1 (CNAN) Road to Ixcatlan, 5 km N Cuicatlán, Oaxaca, México (702 m) 08/11/2005 N 17° 48.914' W 97° 00.323', cols. O. Francke, M. Córdoba, A. Jaimes and G. Montiel. 2 (CNAN) Road Cuicatlán–Oaxaca 33 km S Cuicatlán, Oaxaca, México (1 574 m) 09/11/2005 N 17° 34.914' W 96° 56.928', cols. O. Francke, M. Córdoba, A. Jaimes and G. Montiel. 1 (CNAN) Zapotitlán de las Salinas (botanical garden), Puebla, México (1 497 m) 30–31/10/2003 N 18° 20' 1.4^'' W 97° 27' 7.5^", col. R. Paredes. 3(CNAN) Cuicatlán, Oaxaca, México (620 m) 23/07/1998 N 17°47'55" W 96°57'35", col. S. Zaragoza.

Centruroides hoffmanni. 1 (CNAN) Microwave station 9 Puntas, road Oaxaca–Tehuantepec, Oaxaca, México 09/09/1979 (55 m) N 16° 19' 28" W 95° 14' 20" col. C. Márquez. 1 (CNAN) Morro Mazatán, Oaxaca, México 14/03/1990 (20 m) N 16° 05' 53" W 95° 22' 46" col. E. Barrera and A. Cadena. 1(CNAN) Road to Nizanda, Ixtepeji, Oaxaca, México 12/08/2002 (100 m) N 16° 39' 28" W 95° 00' 42" col. R. Paredes. \$ (CNAN) Ixaltepec, Huiditou, Oaxaca, México 26/12/2000 (neither altitude nor georeference available) col. E. Cabrera. 3, 3 (CNAN) 5 km west of San Miguel Tenango 02/11/2004 (1 571 m) N 16° 13' 30.9", W 95° 35' 57.2", col. O. Francke, G. Villegas and R. Paredes.

Etymology. The specific Spanish epithet "serrano", that means "belonging to the mountain range", is used as a noun in apposition.

 

Remarks

Sexual dimorphism: the pectinal tooth count is higher in males and the carapace longer in adult females. The carapace length/segment V length ratio is 0.70 times on males whereas on females it is 0.86; the vesicle length/ aculeus length ratio is 1.16 times on males whereas on females it is 1.02.

Centruroides serrano sp. nov. is related to C. baergi on account of their similar size, but it is clearly distinguished by the following characters: on C. serrano the subaculear tooth is well developed, whereas it is very small or obsolete on C. baergi (Figs. 8–9). A higher pectinal tooth count on C. serrano (male=23 to 27, Mode=24, n=20 and female= 20 to 23, Mode=22, n=19) whereas on C. baergi it is lower (male= 21–23, Mode=23, n=20 and female= 18–22, Mode=20, n=20); the anterior margin of the basal pectinal piece on C. baergi is straight and the posterior margin is rounded whereas on C. serrano it is not (Figs. 12-13); the inner accessory denticle count of the pedipalp movable finger (only in adults, males and females) is higher on C. serrano (30 to 46, Mode=35, n=10) than on C. baergi (28 to 34, Mode=30, n=10); the outer accessory denticle count of the pedipalp movable finger (only on adults, males and females) is also higher on C. serrano (31 to 45, Mode=37, n=10) than on C. baergi (31 to 38, Mode=33, n=10).

Centruroides serrano sp. nov. is related also to C. nigrovariatus on account of the shape of the subaculear tubercle but it is clearly distinguished by differences in a variety of features. Most conspicuous of these differences is overall size, with C. nigrovariatus adults, at 38–52 mm being conspicuously smaller than those of C. serrano (51–59 mm). Likely associated with its larger size is the higher pectinal tooth count in C. serrano (male= 23–27, Mode=24, n=20; female= 20–23, Mode=22, n=19) as compared to that of C. nigrovariatus (male = 19–22, Mode=21, n=10 and female = 17–20, Mode=19, n=10). Similarly, the inner accessory denticle count of the pedipalp fixed finger (only in adults, males and females) is higher in C. serrano (25 to 39, Mode=29, n=20) than in C. nigrovariatus (20 to 29, Mode=24, n=10). The outer accessory denticle count of the pedipalp fixed finger (only in adults) is also higher on C. serrano (31 to 41, Mode=35, n=20) than on C. nigrovariatus (22 to 31, Mode=31, n=10). A distinguishing feature that is not as clearly size–related is the orientation of the subaculear tubercle, which points towards the base of the aculeus in C. nigrovariatus whereas in C. serrano it points toward the middle of the aculeus (Figs. 8 and 10).

Centruroides serrano sp. nov. is also related to C. hoffmanni on account of the shape of the subaculear tubercle (Figs. 8 and 11) and with similar pectinal tooth counts on males and females. The 2 species can be separated by the following characters: males of C. hoffmanni are smaller (36 to 49 mm, following Armas et al., 2005; whereas on C. serrano=54 to 59 mm), and the metasomal segment V is wider than the segment I on males of C. serrano (1.1 times wider) whereas on males of C. hoffmanni the segment V is narrower than segment I (ratio= 0.8).

Know distribution of Centuroides baergi.

 

Acknowledgments

We would like to thank Oscar Francke for the review of the manuscript and his support through these years. The senior author would like to thank Oscar Francke, Víctor Jara, Alejandro Valdez, Héctor Montaño and Alfonso Ballesteros who helped collect the specimens, to the Biological Sciences Graduate Program of Universidad Nacional Autónoma de México (UNAM) and to the Consejo Nacional de Ciencia y Tecnología (CONACyT, México) for financial support. Special thanks to the people of San Melchor Betaza and San Francisco Cajonos communities for their suggestions of some places to collect within their territories. Mayra Alcántara assisted in the edition of the figures.

 

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