Sofía Solórzano

Liana diversity and reproductive attributes in two tropical forests in Mexico

We describe liana diversity and variation in morphology of flowers and diaspores in two tropical forests in Mexico: a seasonally deciduous forest at Chamela, Jalisco and a lowland rain forest at Chajul, Chiapas. Flowers were classified as inconspicuous (≤1 cm in length and white or pale green flowers) or conspicuous (> 1 cm and brightly colored flowers). Dispersal syndrome was classified as anemochory, barochory, and zoochory. We recorded a higher number of lianas species in Chajul (128 spp.) than in Chamela (71 spp.). In both sites, families with the highest number of species were Bignoniaceae, Leguminosae, Sapindaceae, and Malphigiaceae, and almost half of the liana species had inconspicuous flowers. Most of the species had an abiotic syndrome of dispersal with 40 (56.3%) and 71 (55.5%) wind-dispersed species in Chamela and Chajul, respectively. Zoochory was significantly associated with inconspicuous flowers and anemochory with conspicuous flowers. Our results suggest that (1) flower morphology and dispersal type are not related with the amount of rainfall and (2) lianas are more prone to be wind-dispersed.

CONSERVATION PRIORITIES FOR RESPLENDENT QUETZALS BASED ON ANALYSIS OF MITOCHONDRIAL DNA CONTROL-REGION SEQUENCES

Abstract The Resplendent Quetzal (Pharomachrus mocinno) is a threatened bird species classified into two putative subspecies (P. m. mocinno and P. m. costaricensis) and distributed in cloud forests of seven countries in Mesoamerica. Because the birds are rare, tissue samples are difficult to obtain, but we analyzed genetic diversity in 25 quetzals from five countries based on 255 bp of domain I of the control region of mitochondrial DNA. Eight haplotypes were detected. Nucleotide diversity for Mexico (P. m. mocinno: 0.0021) and Panama (P. m. costaricensis: 0.0026) were low, and did not differ from the values estimated for other birds species irrespective of whether they were endangered. A haplotype tree rooted with the Pavonine Quetzal (P. pavoninus) recovered two reciprocally monophyletic clades corresponding to each subspecies, so we propose that each subspecies be considered as an evolutionarily significant unit for conservation planning. A minimum spanning network showed the number of genetic differences separating haplotypes within subspecies was small relative to the number of substitutions among them, indicating strong population subdivision (FST = 0.37). In spite of the limited sampling we propose that in conservation practice Mexico–Guatemala, Nicaragua, El Salvador, and Panama be considered preliminarily as independent conservation management units since they each have unique haplotypes. Additionally, these countries should construct international agreements to protect the natural vegetation corridors among cloud forests of Mesoamerica and to curtail the illegal trade of quetzals. Prioridades de Conservación para el Quetzal Basadas en el Análisis de la Región Control del ADN Mitocondrial Resumen. El quetzal (Pharomachrus mocinno) es una especie de ave amenazada clasificada en dos subespecies (P. m. mocinno y P. m. costaricensis) distribuidas en los bosques de niebla de siete países de Mesoamérica. Debido a que ésta es un ave rara, las muestras de tejido son difíciles de obtener, pero pudimos analizar la diversidad genética en 255 pb del dominio I de la región control del ADN mitocondrial en 25 quetzales procedentes de cinco países. Se encontraron ocho haplotipos. La diversidad nucleotídica para México (P. m. mocinno: 0.0021) y Panamá (P. m. costaricensis: 0.0026) fue baja, pero no difiere de la estimada para otras especies de aves amenazadas o no amenazadas. El árbol de haplotipos enraizado con P. pavoninus mostró dos clados recíprocamente monofiléticos, correspondiendo cada uno a cada subespecie, por lo que proponemos que para planes de conservación cada subespecie sea considerada como unidad evolutiva significativa independiente. Una red de distancias mínimas mostró que el número de diferencias genéticas que separa a los haplotipos dentro de las subespecies fue pequeño con respecto al número de sustituciones que existe entre ellas, indicando una fuerte división poblacional (FST = 0.37). Considerando nuestro muestreo limitado proponemos que para fines de conservación prácticos México– Guatemala, Nicaragua, El Salvador y Panamá sean considerados preliminarmente como unidades de manejo independientes ya que éstos presentan haplotipos únicos no compartidos entre localidades. Además, estos países deberían firmar acuerdos internacionales para proteger los corredores de vegetación naturales entre los bosques de niebla de Mesoamérica y tratar de reducir el comercio ilegal de los quetzales.

Impacts of the loss of neotropical highland forests on the species distribution: a case study using resplendent quetzal an endangered bird species

We evaluated the impacts of land-cover changes of evergreen cloud forests on the distribution of quetzals in the four mountain regions of Chiapas, Mexico. The land-cover changes were estimated comparing satellite images of 1970 and 2000. We also simulated the amount of remnant forests 50 years in the future. The past and the current distributions of quetzals were based on literature records and recent field surveys. Our results showed that in 1970 the forests occupied 973 km 2 , and in 2000, 312 km 2 , and annual loss from 3.34 to 6.85%. Our simulation suggests that 50 years from now, only one region will maintain evergreen cloud forests. In addition, we documented literature reports of 39 forests inhabited by quetzals, but in 2001 there remained 11 smallisolated forests. In order to guarantee the survival of this species, conversation efforts must be made to protect the quetzal and its habitat throughout the entire Mesoamerica region. # 2003 Elsevier Ltd. All rights reserved.

Isolation, characterization and cross-amplification of polymorphic microsatellite loci in the threatened endemic Mammillaria crucigera (Cactaceae)

The cactus Mammillaria crucigera is a threatened species endemic to central Mexico. As a means of assessing population genetic status of these species, eight microsatellite markers were developed. These primers were tested in 40 individual from two wild populations. The results showed that these primers will be useful to describe population structure and aid to the conservation of species. The eight primers were tested in other Mammillaria species and most of them showed successful amplification.

Identification of conservation units of Mammillaria crucigera (Cactaceae): perspectives for the conservation of rare species

Background: Rare cactus in the Americas and other species worldwide are threatened species because of their high level of habitat specialisation, narrow distribution range and continuing population decline. Aims: To identify management units (MUs) based on genetic variability and demographic structure in order to propose assertive conservation actions for Mammillaria crucigera and to provide a model case study for other species that are under similar threats. Methods: We genotyped through eight microsatellite loci in 171 individuals and described demographic structures in six populations of this cactus based on plots of 1 m2. Results: Across populations with a mean density of 2.6 m−2 and a total of ~500 individuals counted, 30% of the individuals were reproductive (diameter >2 cm). The total heterozygosity was low (HO = 0.54), but the inbreeding coefficient (FIS = 0.29) and the allele diversity (NA = 20) were high. Four genetic groups were distinguished, although considering the demographic structure, we propose three MUs. Conclusions: It is critical to maintain the genetic connectivity within and among MUs, which can only be achieved through cooperation between government authorities and local habitants to halt the degradation and further destruction of the remnant populations. Searching MUs allows the identification of critical areas for conservation issues for all species whose extant populations are in a fragmented landscape.

Phylogenetic relationships in the genus Florestina (Asteraceae, Bahieae)

Florestina is shown to consist of six annual species occurring mostly in arid and semiarid regions of Mexico. Florestina species are morphologically similar and consequently phylogenetic relationships within the genus are poorly understood. We present a phylogenetic study based on morphological characters, DNA sequences of nuclear non-coding spacers (ETS and ITS) and chloroplast non-coding spacers (rpl32-trnL and trnC-petN). The ETS and ITS spacer-based phylogenies allowed several well-supported conclusions: (1) the genus Florestina is monophyletic and Palafoxia is its closest relative; (2) Florestina latifolia and F. platyphylla form a strongly supported clade; (3) four taxa that are morphologically very similar, F. liebmannii, F. pedata, F. simplicifolia, and F. tripteris, are phylogenetically closely related and based on the sequence data we suggest that these should be recognized as only two species, one comprising F. pedata and F. simplicifolia, which shows wide morphological variation throughout its distributional range; and the other comprising F. liebmannii and F. tripteris; (4) F. lobata and F. purpurea are species very distinct from the remainder of the species in Florestina. Our phylogenetic analyses suggest that hybridization and introgression may be involved in the evolutionary history of Florestina.

Genetic Diversity and Structure of the Military Macaw (Ara militaris) in Mexico: Implications for Conservation

The Military Macaw (Ara militaris) is a globally threatened species with a fragmented distribution, and assessing the genetics of populations could help identify conservation units. Nine microsatellites were used to analyze 86 samples in seven localities along the Sierra Madre Occidental, the Sierra Madre del Sur, and the Sierra Madre Oriental in Mexico. Results showed that the Military Macaw has moderate levels of genetic diversity, similar to that found in other macaw species in Latin America. This species shows a high genetic structure; we find a genetic break between localities separated by the Central Plateau and the Trans-Mexican Volcanic Belt, which serve as geographic barriers. However, the locations within each genetic group are not genetically differentiated. It was observed that three locations of the Military Macaw have excess homozygotes, which could indicate a small effective size of the population and in combination with genetic isolation could increase the risk of extinction of the species. We propose two genetic groups for the species, the first comprising localities in the Sierra Madre Occidental and the Sierra Madre del Sur, and the second comprising localities of the Sierra Madre Oriental. According to the genetic differentiation, which was significant between the physiographic regions, and the unique allelic richness shown in this study, these two groups should be considered as independent conservation units. We strongly recommend the conservation and restoration of the natural habitats of the Military Macaw to maintain and increase the size of its population and recover and expand its original geographical distribution.