Fenología reproductiva de árboles en una zona montañosa del occidente de México

El conocimiento de los patrones de floración y fructificación de las especies arbóreas es de importancia por la relación que presentan con polinizadores, dispersores y su contribución para conocer las mejores fechas de recolecta de flores y frutos con propósitos taxonómicos y reproductivos. Por lo anterior, se analizaron los patrones de floración y fructificación de las especies arbóreas de la Estación Científica Las Joyas y áreas aledañas en la sierra de Manantlán en el estado de Jalisco; y se indagó su correlación con la precipitación, temperatura, insolación, humedad relativa y evaporación. Se revisaron ejemplares de herbario con flores y frutos recolectados a partir de 1985 que forman parte del acervo del Herbario ZEA de la Universidad de Guadalajara. Se realizó la estadística descriptiva de los datos mediante histogramas; además se hicieron análisis de varianza de una vía en busca de diferencias entre los períodos de floración y fructificación, y correlaciones de Pearson para determinar las relaciones entre la floración y fructificación con las variables ambientales. Se registró que la mayor riqueza de especies en floración y fructificación se presentó en la estación seca del año. El tipo de vegetación con más especies fue el bosque mesófilo de montaña y el patrón de floración y fructificación en esta comunidad vegetal se ajustó al patrón general de todos los taxones. La riqueza de especies arbóreas en floración y fructificación tuvo correlación negativa y significativa con la humedad relativa y la precipitación, las variables ambientales de mayor importancia.

Sedum dormiens (Crassulaceae, Sempervivoideae, Sedeae): a new species from the Sierra de Manantlán, Mexico

Sedum dormiens (Crassulaceae) from the Sierra de Manantlán in Jalisco, Mexico, is described. The distinctive characters of the species are its chamaephytic nature, capillary roots, formation of large colonies, tetramerous flowers with white petals, dormant terminal and lateral buds in the mother plant and connate fruits of ½–¾ its length. The habitat and morphology of the species is illustrated and its relationships with close species presented. Its conservation status was categorized as Endangered (EN).

First record of a mass swarming behavior of Chauliognathus vestitus Champion, 1914 (Coleoptera: Cantharidae) with comments on other Chauliognathus from Colima, México

In this work we document a case of mass swarming of the Mexican soldier beetle Chauliognathus vestitus Champion, 1914 from El Terrero locality, within the Sierra de Manantlan Biosphere Reserve, in Colima, Mexico. Two other species of soldier beetles Chauliognathus togatus Waterhouse, 1878 and Chauliognathus sp. were observed at El Terrero, coexisting with C. vestitus, but their numbers were considerably lower. An updated list of Chauliognathus species from the state of Colima is included. Our observations are the record, to our knowledge, of the second cantharid species exhibiting a mass flying behavior among more than 450 described Chauliognathus in the world, and the first record of this behavior among soldier beetles in the American continent.

Sideroxylon cochranei (Sapotoideae, Sapotaceae): a new cloud forest tree species from the Sierra de Manantlán and Cuale in western México

Sideroxylon cochranei (Sapotaceae) from Sierra de Manantlán and Cuale, in Jalisco, México is here described and illustrated. It is morphologically close to S. salicifolium, but it differs from the latter in being montane cloud forest trees versus sea-shore to lower montane tropical trees, also in having clustered leaves with longer petioles and sepals and larger fruits. A key to the species of Sideroxylon in western Mexico and a distribution map are provided. According to IUCN criteria, its conservation status was assessed as critically endangered (CR).

Molecular data suggest that Heteromys irroratus bulleri should be recognized as a species-level taxon

Recent collecting surveys in the Sierra de Manantlán Biosphere Reserve, Jalisco (México), uncovered the existence of a new population of the Mexican spiny pocket mouse, Heteromys irroratus. Because the subspecies H. i. bulleri and H. i. jaliscensis occur nearby, our objective was to properly determine the taxonomic identity of the novel sample. Also, we evaluate its distinctiveness, both in terms of genetic divergence and phylogenetic placement, relative to other members of H. irroratus. Preliminary, we compared external and cranial measurements of recently collected individuals to those reported for representatives of the subspecies of H. irroratus occurring close by. In addition, we examined levels of genetic differentiation and phylogenetic relationships, based on sequence data of the Cytochrome b, among this population and other members of H. irroratus, including an individual from Sierra de Juanacatlán, Jalisco, the type locality of H. i. bulleri. Phylogenetic relationships were estimated using Maximum Likelihood and Bayesian Inference methods and levels of genetic divergence were assessed employing Kimura-2-parameters genetic distances. Samples from Sierra de Manantlán and Sierra de Juanacatlán were grouped together in a well-supported haplogroup and genetic distances between them were lower than < 1.02 %. Our phylogenetic hypothesis shows that H. i. bulleri represents the sister group to all other samples of H. irroratus but that, genetically, is a very divergent lineage. Distances values between H. i. bulleri to any of the other groups were > 10.05 %. Comparison of external and cranial measurements showed that, in average, individuals from Sierra de Manantlán are larger than those of H. i. jaliscensis, but more similar in size to H. i. bulleri. Our results show that the new population of the Mexican spiny pocket mouse from Sierra de Manantlán belongs to H. i. bulleri. In addition, the phylogenetic separation and the high levels of genetic divergence of H. i. bulleri, relative to other members of H. irroratus, suggest that the first should be recognized as a species-level taxon. Considering the scarce collecting records of H. i. bulleri and the known area of occurrence, that is very restricted, this taxon may warrant special conservation status.

Scolytinae y Platypodinae (Coleoptera: Curculionidae) de un bosque mixto de pino-latifoliadas de la Sierra de Manantlán, Jalisco, México

Como parte de una evaluación de causas de mortalidad de árboles, se determinó la composición de especies de escarabajos de la corteza en un bosque mixto de pino-latifoliadas en la Reserva de la Biosfera Sierra de Manantlán, Jalisco, México. En dos rodales con condiciones ambientales similares se realizaron colectas mensuales utilizando dos tipos de trampas (recipientes con alcohol al 70% y láminas de pegamento; 46 de cada tipo), cubriendo un ciclo anual (julio de 2018 - agosto de 2019). Fueron colectadas y determinadas 17 especies de la familia Curculionidae (15 Scolytinae y dos Platypodinae); adicionalmente, se registraron siete taxones de las familias Histeridae (tres), Cleridae (tres) y Trogossitidae (una) que se comportan como depredadores de escarabajos de la corteza. Diez de las especies identificadas son nuevos registros para el estado de Jalisco: Amphicranus rameus, A. melanurus, Corthylus comatus, C. fuscus,Gnathotrichus sulcatus, Hylurgops incomptus, Monarthrum laterale, Pseudips mexicanus (Scolytinae) y Euplatypus longius y E. pini (Platypodinae). Los rodales mostraron diferencias en la abundancia de individuos colectados, lo cual se atribuye a la fase de desarrollo del brote de las poblaciones de descortezadores al momento de la medición. Los escarabajos ambrosiales fueron los más abundantes,seguidos por los Histeridae, Dendroctonus, Cleridae y Trogossitidae. La comparación del número de capturas por tipo de trampa sólo mostró diferencias significativas para los ambrosiales (t= 3.53, p= 0.001), siendo más efectivas las trampas de alcohol que las de pegamento (media del número de capturas 19.7 ± 2.3 y 8.8 ± 2 respectivamente). La mayor parte de las especies encontradas tienen amplia distribución geográfica, pero no se habían registrado para el estado Jalisco, lo cual pone de manifiesto la necesidad de más estudios taxonómicos, ecológicos y biogeográficos sobre los escarabajos de la corteza, teniendo en consideración su importancia ecológica y económica en los ecosistemas forestales.

Post-fire recovery of ecosystem carbon pools in a tropical mixed pine-hardwood forest

Aim of the study: To analyze the recovery pattern of carbon pools in terms of size and the relative contribution of each pool to total ecosystem C along a fire chronosequence of tropical mixed pine-hardwood forest.Area of the study: Las Joyas Research Station (LJRS), core zone of Sierra de Manantlán Biosphere Reserve (SMBR) in the state of Jalisco, central western Mexico.Materials and methods: Carbon stored in aboveground plant biomass, standing dead trees, downed woody debris, forest floor, fine roots and mineral soil, was compared with a nested analysis of variance (ANOVA) in post-fire stands of eight-year-old, 28- and 60-year-old stands of mixed Pinus douglasiana-hardwood forest.Main results: The total ecosystem carbon in eight-year-old stands was 50% lower than that of 60-year-old stands. Carbon content in the biomass and mineral soil increased with stand age. The carbon in the biomass recovered to the undisturbed forest in the 28 years of succession. The main C storage in the eight-year-old stands were the mineral soil (64%) and downed woody debris (18%), while in the 28- and 60-year-old stands, live tree biomass and mineral soil were the two largest components of the total C pool (43% and 46%, respectively).Research highlights: We found a significant effect of high-severity fire events on ecosystem C storage and a shift in carbon distribution. The relatively fast recovery of C in ecosystem biomass suggests that mixed Pinus douglasiana hardwood forest possess functional traits that confer resilience to severe fire events.Key words: chronosequence; carbon dynamics; mineral soil; Pinus douglasiana; fire effects.Abbreviations used: LJRS, Las Joyas Research Station; DBH, diameter at breast height; DL, duff layer; LL, litter layer; DWD, downed woody debris; ANOVA, analysis of variance; CO2, carbon dioxide; SMBR, Sierra de Manantlán Biosphere Reserve; C, carbon. AGV, above ground vegetation.

Vegetación de bordes en un bosque mesófilo de montaña del occidente de México

<p>Species composition, diversity, structure and microclimate were compared in two edge type of montane cloud forest (FF, edges with pine forest and FS, secondary shrubland) within a forest-edge-exterior gradient at Sierra de Manantlán Biosphere Reserve (Jalisco, Mexico). The cloud forest presented higher richness (126 species, 52 interior habitat specifi c) than pine forests (84) and shrublands (71). Richness and diversity were similar in FF, but species replacement was higher in FS. Density, diameter structure, basal area and canopy cover were major in FF than in FS. Microclimatic and soil condition, was gradual in FF edges and abrupt in FS edges. Tree species of the cloud forests (high density of seedlings and saplings &lt;5 cm diameter breast height) are colonizing the understory of adjacent pine forests, whereas in shrublands their establishment appears to be limited by competition with shrubs and herbaceous species and microclimatic conditions. Our results highlight the importance of considering edge type contrast in conservation and restoration of cloud forest in forest landscapes.</p>

Estructura, composición florística y diversidad de especies leñosas de un bosque mesófilo de montaña en la Sierra de Manantlán, Jalisco

In this paper we describe the structure, floristic composition and woody (tree and shrub) species diversity of a cloud forest at Cuzalapa, Sierra de Manantlán, Jalisco. Two localities with four 2,500 m2 plots each were established at El Durazno and La Pareja. All species present in the plots were identified and recorded, and their diameters at breast height (DBH ≥ 3cm) and heights measured. Forest structure is described using the relative values of density and basal area; in addition, a diagram of forest profile was drawn for each plot. Among-plot similarity was assessed with Sørensen 's Index. Species diversity was evaluated using Shannon-Wiener 's, Simpson's, and Fisher's α indexes. In the total sampled area (2 ha) 2,086 individuals belonging to 101 species (including two new records for the flora de la Sierra de Manantlán, Sapranthus foetidus and AIchornea latifolia), distributed in 75 genera and 44 farnilies, were recorded. The families with the largest numbers of species were: Leguminosae (8), Solanaceae and Fagaceae (7 each), Moraceae and Compositae (6 each), Lauraceae (5), and Rubiaceae (3). Tree density at El Durazno and La Pareja was 1,084 and 1,002 trees ha-', and basal area was 38.7 and 31.9 m2 ha-', respectively. At both localities, Styrax radians had the highest relative importance value. Forest structure and species composition at both localities correspond to tracks of transitional forest between early to intermediate stages, which results from recurrent anthro- pogenic disturbances such as logging 50 years ago. Species diversity in Cuzalapa is one of the highest ever recorded for cloud forests of Mexico, which presumably is a consequence of anthropogenic and natural disturbances. Both kind of disturbances are important forces in maintaining the structure, species composition, and high species diversity in this cloud forest.

Diversidad florística del bosque mesófilo en el norte de Chiapas y su relación con México y Centroamérica

The distribution of woody genera in the montane cloud forest in the northern highlands of Chiapas was registered and compared with other 23 localities in Mexico and Central America. A total of 312 genera in 99 families were recorded. The most diverse families were Rubiaceae (19), Leguminosae (16), Ericaceae ( 15) and Compositae ( 14). Quercus, Clelhra, Cornus, Oreopanax, and Ceslrum were present in more than 95% of the si tes, while 32 genera ( 10%) alone were registe red once. Non-metric multidimentional scaling analysis showed the presence of six groups of localities according to their diversity values and geographical position. Sierra de Manantlán, El Triunfo, Cordillera of Talamanca, and Northern highlands of Chiapas were the most diverse localities. The greater proportion of the genera (41 %) have a meridional distribution (except pantropical), 15% holarctic, 4% american-african, 9% malayan-american, 3% austral-antarctic, 14% pantropical, 5% widely distribution and 9% of the genera are considered exclusive of Mexico and/or Central America.