Notas Científicas

 

First record of Euagrus pristinus O. P.–Cambridge, 1899 (Araneae: Dipluridae) for Chiapas, Mexico

 

Primer registro de Euagrus pristinus O. P.–Cambridge, 1899 (Araneae: Dipluridae) para Chiapas, México

 

Kaleb ZÁRATE–GÁLVEZ^*, Miguel Ángel GARCÍA–VILLAFUERTE^** and César Andrés PÉREZ BONIFAZ^***

 

Colección de Arácnidos, Facultad de Ciencias Biológicas, Universidad de Ciencias y Artes de Chiapas. Libramiento Norte Poniente 1150, Colonia Lajas Maciel, C.P. 29039. Tuxtla Gutiérrez, Chiapas, MÉXICO. ^*kalebzg7@gmail.com, ^**mgarciavillafuerte@yahoo.com, ^***cesarandres2x1@yahoo.com.mx

 

Recibido: 16/06/2009
Aceptado: 18/02/2010

 

RESUMEN

Se registra por primera vez para el estado de Chiapas, México a Euagrus pristinus O. P.Cambridge, 1899, anteriormente solo registrada para los estados de Hidalgo, Nuevo León, Oaxaca, Puebla y San Luis Potosí.

 

The funnel–web mygalomorph spiders of genus Euagrus Ausserer, 1875 are found from the Southern U.S.Ato Costa Rica. It is represented by 22 species, 17 of which are found in Mexico (Platnick 2009). They live in a great variety of habitats, from deserts to alpine forest and caves. Euagrus species build irregular webs with a sometimes branching tubular retreat hidden under rocks, in the soil or in other sheltered microhabitat, and an exposed entrapment web composed of a mixture of funnels and sheets, extending out from the aperture of the retreat (Coyle 1988).

Euagrus lynceus Brignoli, 1974 was the first species of this genus described for Comitán, Chiapas as type locality. Subsequently, Coyle (1988) cited this species from other localities in Chiapas, Oaxaca, Tabasco and Veracruz, and described E. carlos Coyle, 1988 from Cueva del Tío Ticho, Comitán, Chiapas. In his work, Coyle (1988) also recorded E. pristinus O. P.–Cambridge, 1899 for Hidalgo, Nuevo León, Puebla and San Luis Potosí, with the most southern and numerous records in Oaxaca. Until now, no additional species had been reported of this genus for Chiapas. In the present work we inform the presence of E. pristinus for the first time in Chiapas, Mexico.

Abbreviations used in this work: BD (palpus bulb diameter in ventral view), CL (carapace length), ITS (total number of spines on the ventral and prolateral surfaces of male tibia I), PL (palpus length in retrolateral view), CA–UNICACH (Colección de Arácnidos, at the Facultad de Ciencias Biológicas, Universidad de Ciencias y Artes de Chiapas, Tuxtla Gutiérrez, Chiapas, México). Measurements were made with an ocular micrometer at 10X on a Carl Zeiss Stemi DV4 stereomicroscope, photographs taken on the same microscope with a Samsung Digimax A50 camera.

One specimen was collected at Cerro Tres Picos, Biosphere Reserve "La Sepultura", Villaflores, Chiapas, México. Cerro Tres Picos is characterized by abrupt slopes. The Biosphere Reserve "La Sepultura" is the most western reserve of the Sierra Madre del Sur, South–western of Chiapas, México. Climate in the site is C(m)(w) in Koppen's classification, modified by E. García (Cardoso 1979), humid temperate with abundant summer rains, winter rains less than 5% of the total annual precipitation (2,000 to 3,500 mm), temperature fluctuations 15–18 °C, are characteristic to highlands and slopes (INE/SEMARNAP 1999).

Material examined: MEXICO: Chiapas: one male adult from Cerro Tres Picos (16° 11' 57.6" N, 93° 36' 05.7" W, elevation 1900m), Municipio de Villaflores, Chiapas, evergreen cloud forest, collected with pitfall trap laid from 16/02/2008 to 14/03/2008, (Colls. K. Zárate Gálvez, C. A. Pérez Bonifaz, G. Salinas Pérez and M. A. Lorena Acuña, CA–UNICACH). Measurements: CL = 4.9 mm; ITS = 23; BD = 0.51 mm; PL = 1.28 mm; BD(100)/PL = 40.

Genus diagnosis: Euagrus can be easily distinguished from other genera of Dipluridae by absence of maxillary cuspules, the males have the presence of spines on the tip on the cymbium (Fig. 1), a prominent ventral median apophysis occupying the proximal half to two–thirds of tibia II (Fig. 2), two or three ventral keels on metatarsus II and patches of prominent curved spinules on opposing lateral surface of femora I and II (Coyle 1988).

 

Species diagnosis: male of E. pristinus can be distinguished from other Euagrus species by abdominal dorsum without prominent transverse light markings, no retrolateral preening comb on metatarsus II, palpal organ (Fig. 1) rather elongated [BD= 0.24–0.54 mm, PL = 0.67–1.30 mm, BD(100)/PL= 35–43], usually have more ITS (16–47) and body size usually larger (CL= 2.5–5.8 mm). Ventral face of tibia II with two very long strong spines on apex of apophysis, and one or two shorter but moderately large spines just retrolateral and distal of these, occasionally one or two long slender spines on proximal slope of apophysis; distally after the apophysis, there are smaller spines regularly distributed (hardly ever with an area devoid of spines) along the ventral surface and these decrease gradually in length (Fig. 2) (Coyle 1988).

 

ACKNOWLEDGEMENTS

We thank F. A. Coyle who kindly sent us his papers, to A. Valdez–Mondragón, C. R. Lucio–Palacio and two anonymous reviewers for their comments and revision of this work. Field work assistance was provided by G. Salinas–Pérez and M. A. Lorena–Acuña, as well as people from Nueva Independencia, Villaflores. To J. Murgía–González, I. Landero–Torres and C. M. Galán–Páez (Facultad de Ciencias Biológicas y Agropecuarias, Región Orizaba–Córdoba, Veracruz) for the access to the laboratory. This study was granted by FOMIX–Chiapas (Fondo Mixto CONACYT –Gobierno del Estado de Chiapas) through the project CHIS–2006–C06–45752.

 

LITERATURE CITED

Cardoso C, M.D. 1979. El clima de Chiapas y Tabasco. Instituto de Geografía. UNAM. México.         [ Links ]

Coyle, F.A. 1988. A revision of the American funnel–web mygalomorph spider genus Euagrus (Araneae, Dipluridae). Bulletin of the American Museum of Natural History, 187(3):203–292.         [ Links ]

INE/SEMARNAP. 1999. Programa de manejo de la Reserva de La Biosfera La Sepultura. INE/SEMARNAP. México, D. F.         [ Links ]

Platnick, N.I 2009. The world spider catalog, version 9.5. American Museum of Natural History, online at http://research.amnh.org/entomology/spiders/catalog/index.html        [ Links ]