Revista Mexicana de Biodiversidad 83: 100-109, 2012 Diversity and biogeographic affinities of Apionidae (Coleoptera: Curculionoidea) along an altitudinal gradient in El Cielo Biosphere Reserve of northeastern Mexico Diversidad y afinidades biogeográficas de Apionidae (Coleoptera: Curculionoidea) a lo largo de un gradiente altitudinal en la Reserva de la Biosfera El Cielo en el noreste de México Robert W. Jones1 , Santiago Niño-Maldonado2 y Jesús Luna-Cozar3 1Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, Avenida de las Ciencias, s/n, 76230 Juriquilla, Querétaro, México. 2Unidad Académica Multidisciplinaria Agronomía y Ciencias, Universidad Autónoma de Tamaulipas, Centro Universitario, 87149 Ciudad Victoria, Tamaulipas, México. 3El Colegio de la Frontera Sur, Carr. Panamericana y Periférico Sur s/n, 29290 San Cristóbal de las Casas, Chiapas, México. [email protected] Abstract. The altitudinal and temporal distributions of species in the family Apionidae (Coleoptera: Curculionoidea) were studied in El Cielo Biosphere Reserve (ECBR) in the state of Tamaulipas, northeastern Mexico. Species richness, diversity and abundance were recorded along an altitudinal gradient, from 100 to 1 900 m. A total of 571 individuals of 51 species were collected, representing 30% of the total species of Apionidae recorded for Mexico. Richness estimators (Chao 2) indicated that 75% of the species present were sampled. Species richness and diversity was greatest in tropical forests. Species geographic distributions were found to fall into 3 categories: mega-Mexico, tropical and temperate. The majority of the species (55.3%) were restricted to mega-Mexico (southern southwestern US to northern Nicaragua), with fewer species with tropical (27.7%) and temperate (17.0%) distributions. Species with tropical distributions had highest diversity and greater overall abundance in low elevations in tropical forests when compared to higher elevation forests (cloud and pine/oak). In contrast, diversity and abundance for species with temperate and mega-Mexican distributions were similar in all forest types. Greater richness and abundance occurred during the dry season (December through May) than the rainy season, suggesting populations of Apionidae were in immature stages during this latter period, with active adults predominating during the dry season, many of which were probably in a non-reproductive physiological state. Key words: Coleoptera, biodiversity, biosphere reserve, Apionidae, neotropical. Resumen. Se estudiaron las distribuciones altitudinales y temporales de especies de la familia Apionidae (Coleoptera: Curculionoidea) en la Reserva de la Biosfera El Cielo, en el norte de México. Riqueza, diversidad y abundancia fueron registrados a través de un gradiente altitudinal de 100 hasta 1 900 m. Se recolectó un total de 571 individuos de Apionidae de 51 especies. La diversidad de especies fue mayor en la selva tropical. La distribución geográfica de las especies corresponde a 3 categorías: mega-México, tropical y templada. La mayoría de las especies (55.3%) pertenecen a la categoría mega-México (sur del suroeste de los Estados Unidos hasta el norte de Nicaragua), seguido por especies con distribución tropical (27.7%) y templada (17.0%). Las especies con distribución tropical tuvieron mayor diversidad y abundancia en elevaciones bajas (selvas tropicales). En contraste, la diversidad y abundancia de las especies con distribución templada y mega-México fueron parecidas entre altitudes y tipos de vegetación. Se encontró mayor riqueza y abundancia durante la época de secas (diciembre a mayo) que en la época de lluvias, lo cual sugiere que las poblaciones de Apionidae estuvieron en etapa de inmaduros durante este último periodo, con una predominancia de adultos activos durante la época de secas, los cuales probablemente estuvieron en un estado fisiológico no-reproductivo. Palabras claves: Coleoptera, biodiversidad, reserva biosfera, Apionidae, neotropical. Introduction biogeographic maps (Wallace, 1876; Udvardy, 1975; Olson et al., 2001; Cox and Moore, 2005), the Neotropical Mexico has long been recognized as a “transition region of Mexico is generally shown to occur south of zone” between the Nearctic and Neotropical biogeographic the Isthmus of Tehuantepec and extend north along both realms (Wallace, 1876; Morrone, 2005). In generalized western and eastern coastal areas approximately to the Tropic of Cancer. In contrast, the Nearctic region extends from the Rocky Mountains south through the central Recibido: 25 febrero 2011; aceptado: 04 agosto 2011 Mexico plateau and along the 2 northern mountains ranges Revista Mexicana de Biodiversidad 83: 100-109, 2012 101 (Sierra Madre Oriental and Occidental), terminating at the O’Brien and Wibmer, 1982); 3), although studies have Transverse Neovolcanic Belt at approximately 18° latitude examined the diversity of various tropical insect groups north. Although this generalized Nearctic-Neotropical along altitudinal gradients (Sánchez-Ramos et al., 1993; pattern is useful for a rough depiction of the distribution Olson, 1994; Lobo and Halffter, 2000; Sandoval and within Mexico of species from these biogeographic Fagua, 2006), none have presented detailed, site specific regions, the actual distribution patterns of individual diversity data for a phytophagous taxa such as Apionidae. species and genera are complex and the result of dispersal We determined the richness, abundance and diversity and/or vicariant speciation processes associated with a of Apionidae along an altitudinal gradient that included wide range of possible geographical or environmental semi-deciduous tropical forest (100-700 m), cloud forest changes in geological time (Halfter, 1987; Noonan, 1988; (800-1 400 m) and mixed pine-oak forests (1 500-1 900 Thomas, 1993; Rzedowski, 1993; Lobo and Halffter, 2000; m), with the limits of vegetation types based on Gonzalez- Marshall and Lieberr, 2000; Morrone and Márquez, 2008). Medrano (2005). Using reported distribution data, we The northern extension of the Sierra Madre Oriental categorized distributions of species of Apionidae into 3 Biotic province (sensu Morrone et al., 2001), and in categories and compared species richness and abundance of particular the region protected within the El Cielo Biosphere the different biogeographic categories along the altitudinal Reserve (ECBR), is one of the geographic areas of Mexico gradient and temporally throughout a year of collection. where the contrast and mixing between the nearctic and The principal questions addressed were the following: neotropical faunal and floral elements is most pronounced. 1), what is the richness and diversity of Apionidae en This reserve is in the state of Tamaulipas, approximately the El Cielo Biosphere Reserve? 2), what are the basic 70 km south of Ciudad Victoria between 22°55’ and 23°25’ biogeographic affinities the species of Apionidae within N and 99°05’ and 99°26’ W (Casas Gonzalez and Requena the reserve? 3), are the species of Apionidae of different Lara, 2005). González-Medrano (2005) reports 10 distinct biogeographic affinities restricted to different altitudes? types of vegetation in ECBR including tropical deciduous and, 4), what are the seasonal patterns in abundances and forests, tropical semi-deciduous forest, cloud forest, pine altitudinal distributions of Apionidae within the vegetation forest, oak forest, pine-oak forest, and with 4 associations types of the reserve? of xeric shrubs on the western portions of the reserve. These vegetation types are often found in close proximity Materials and methods and several associations can often be found within a distance of 10 km, especially where the terrain rises An altitudinal transect was established approximately 8 abruptly (Valiente-Banuet et al., 1995; Gonzalez-Medrano, km north of the town of Gómez Farías, in the municipality 2005). These changes in vegetation provide an opportunity of Gómez Farías, Tamaulipas, México, and oriented in a to examine how different floral and faunal groups are east to west direction from 23°07’56” N, 99°08’50” W distributed and mix within the different habitats. to 23°07’56” N, 99°08’50” W. RBEC is situated in the Our overall objective was to identify the species in terrestrial subregion of the Sierra Madre Oriental (Cuanalo the family Apionidae (Coleoptera: Curculionoidea, sensu de la Cerda et al., 1989), and situated in the Sierra de las Alonso-Zarazaga and Lyal, 1999) and to characterize Cucharas, part of the ancient Sierra de Guatemala (Cámara their distributions and associations in ECBR. Apionidae Artigas and González Rodriguez, 2005). The region is is a family of relatively small weevils (< 7 mm) with composed of tropical karst of medium tropical hills and non-geniculate antenna, elongated trochanter and mountains reaching a maximum of 2 320 m a.s.l., with usually pear-like shape (Anderson and Kissinger, 2002). karstic depressions in the valleys (Cámara-Artigas and Apionidae are widely distributed with approximately González-Rodriguez, 2005). Soils are primarily litisols 1 900 described species worldwide (Oberprieler et al., for the length of the transect. Using the system of 2007) and reported from all the biogeographical regions of classification of Garcia (1973), the climate of the lower the world, except the Antarctica (Alonso-Zarazaga, 2004). sections of the transect up to 700 m is classified as (A) They are phytophagous and relatively host plant specific C(w2) and C(w2) from 700 to 1 900 m (Casa-Gonzalez and (Alonso-Zarazaga,