María Elena Siqueiros-Delgado

Phylogeny of the Bouteloua curtipendula Complex (Poaceae: Chloridoideae) Based on Nuclear Ribosomal and Plastid DNA Sequences from Diploid Taxa

Abstract The Bouteloua curtipendula complex (Poaceae: Chloridoideae) has been treated as a group of 12 species distributed from Canada to Argentina. Due to considerable morphological variation, putative hybridization, polyploidy (including aneuploidy), and apomixis, circumscription of and relationships among taxa have been uncertain. To infer the phylogeny of this complex, two non-coding regions, the internal transcribed spacer (nrDNA) and trnT-L-F (cpDNA), were sequenced and analyzed by maximum parsimony and maximum likelihood methods. Character-state reconstruction was carried out to test the utility of morphological characters used for species circumscription. Nuclear and plastid data revealed similar phylogenetic patterns, albeit with a lower level of resolution from the trnT-L-F sequences. Results support monophyly of the Bouteloua curtipendula complex, but not the species monophyly, except for B. triaena, which forms a strongly supported clade in both phylogenies. The origin of the Bouteloua curtipendula complex seems to be recent with low divergence between taxa. All of the morphological characters used to circumscribe species were found to be homoplasious.

Crioprosopus magnificus Leconte (Coleoptera: Cerambycidae) in Aguascalientes, Mexico: Biological Observations and Geographical Distribution

ABSTRACT Symptoms of wood boring activity and Cerambycidae larvae in living oak trees (Quercus L. spp.) were discovered in October 2006 in the Sierra Fria, Aguascalientes, Mexico. Prompted by this finding, we conducted a field study to determine the wood borer species and its host preference and geographical distribution, and to record biological and ecological data. Adult specimens were obtained by caging infested bole samples in laboratory conditions as well as by installing screen emergence cages on infested trees in several locations in the Sierra Fria. Twenty-nine line transects were sampled in search of wood boring symptoms in living oak trees. Forty adult specimens were obtained during the 32-month study. Based on morphology and behavior, the insect was identified as Crioprosopus magnificus LeConte (Coleoptera: Cerambycidae), a new geographical record for this species. The main host for this insect is Quercus potosina Trel., but it also occasionally attacks Quercus grisea Liemb. and Quercus eduardii Trel. Wood boring symptoms attributed to C. magnificus were found along the Sierra Fria. Beetle emergence was confirmed in four locations. Observations on insect mating, longevity and oviposition are provided.

Polyploidy as a Factor in the Evolution of the Bouteloua curtipendula Complex (Poaceae: Chloridoideae)

Abstract In this paper we assess the impact of polyploidy and hybridization in the Bouteloua curtipendula species complex (BCC). The BCC is a monophyletic group of perennial grasses in the Chloridoideae subfamily. We tested for evolutionary signatures of hybridization and polyploidy in the BCC by obtaining 77 chromosome counts from anther mother cells (2n = 20 to >100) and comparing the phylogenetic pattern of diploids and polyploids in nuclear and chloroplast trees. We sequenced ITS and trnT-L-F regions for 96 and 70 individuals, respectively, resulting in 150 nuclear ribosomal ITS sequences, including 54 cloned sequences. We found no evidence for recombination between ITS sequences with a PHI test. Maximum parsimony and Bayesian analyses were used to estimate the ITS phylogeny. Diploid samples were found in all clades, while most of the polyploid samples were concentrated in a single clade. Cloned diploids contained one to three copies of ITS with >99% sequence similarity. The tetraploids B. purpurea and some B. curtipendula samples had a low amount of variation among ITS copies, while the cloned polyploids possessed several highly divergent ITS copies. Pollen size correlates with ploidy-level in the BCC, but is not a clear indicator of genome size. We found evidence that the BCC lineage has a complicated evolutionary history that has included autopolyploidy and allopolyploidy.

Checklist of the genus Quercus (Fagaceae) of Aguascalientes, México

Twenty-five species of Quercus were collected in the state of Aguascalientes, 11 members of Quercus sect. Lobatae (red oak) and 14 members of Quercus sect. Quercus (white oak). Ten species were newly recorded. Quercus potosina is the commonest and most widely distributed species in the state. Eight species were found only in a single municipality, Calvillo or San Jose de Gracia. The species of Quercus are mainly distributed in oak and pine-oak forest in the western part of Aguascalientes. The municipalities with the greatest numbers of species are San Jose de Gracia, Calvillo and Jesus Maria, while Aguascalientes, Asientos, Cosio, El Llano, Rincon de Romos, Pabellon de Arteaga, and Tepezala have the fewest representatives. San Francisco de los Romo is the only municipality without any Quercus records .