The structure and seasonal changes of earthworm communities were evaluated in a natural Savanna and in an introduced grass-legume pasture in a Colombian oxisol over a period of eighteen months. One plot of 90x90 m was isolated in each of the systems and each month five samples of 1m 2 x 0.5 m and 10 of 20x20x20 cm were randomly selected from a stratified block design. Species richness was similar in the two evaluated plots (7 species), whereas diversity H' index (Shannon and Weaver, 1949) was clearly different, 2.89 in natural Savanna and 1.29 in pasture. This is explained by differences in earthworm community structure. Average annual density in Savanna was 49.8, ranging from 10.8 to 135.8 ind. m -2 , and biomass was 3.3 g m -2(hand-sorting method), ranging from 0.9 to 11.5 g m -2 . In the man-made pasture, density was 80.1 ind m -2 on average, ranging from 24 to 215.8 ind m -2 and biomass was more than tenfold higher, ranging from 29.2 to 110.4 g m -2 . This was especially due to the presence of a large glossoscolecid anecic species, Martiodrilus carimaguensis n. sp.(Jiménez and Moreno, in press), which has been greatly favoured by conversion of savanna to pasture. Endogeic species were dominant in the natural Savanna whereas the anecic species accounted for the 88% of total earthworm biomass in the pasture. Figures of total earthworm density and biomass were significantly different in the two systems studied (t-test). The results indicate a clearly positive response of earthworm communities to improved pastures, a type of land use that is increasingly adopted in moist neotropical savannas.3

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Martiodrilus carimaguensis (Oligochaeta, Glossoscolecidae) is a large, dorsally dark-grey anecic native earthworm species that was found in natural and disturbed savannas in the Oxisols of the Colombian Llanos. The population dynamics of this species were studied in a native savanna and in a 17-yr old grazed grass-legume pasture

Ground-living spiders of different habitats in the Cabaneros National Park, central Spain, each under different management conditions, were studied to characterize their community richness and composition. Five different habitats were selected: Mediterranean forest, abandoned pine plantations and three kinds of dehesas or meadows (differing in their understory management). In three sampling periods, during two springs and one in fall (2001)(2002), a total of 1,152 pitfall traps were deployed in five different habitats. A total of 3,801 adult spiders, representing 105 species from 24 families were collected, among which 13 are considered endemic for the Iberian Peninsula. Correspondence analysis and indicator species analysis showed that spider richness and assemblages differed considerably among the different habitats. The scrub dehesa had the highest ground-living spider richness. Twenty-three indicator species were identified for the different habitats, of which four are considered endemic for the Iberian Peninsula. Gnaphosidae have a high potential as indicators of habitat quality.

A new species, Andiorrhinus (Andiorrhinus) kuru sp. nov., of Glossoscolecidae (Oligochaeta) from the Alto Orinoco, Amazonas, Venezuela, is described. The Makiritare Indians traditionally consume this species of earthworm together with another one called motto (Andiorrhinus (Amazonidrilus) motto Righi and Araujo, 1999) and a few other caterpillars, termites, aquatic insects, and weevill larvae. Andiorrhinus (A.) kuru is a large terrestrial earthworm living in the upland forest of the high river Padamo. The Makiritare collect it by digging into the soil with machetes. The species lives 10–20 cm deep in the soil close to the root mat of the trees.

La macrofauna del suelo incluye a los invertebrados visibles a simple vista que viven, total o parcialmente, dentro del suelo o inmediatamente sobre él. Éstos invertebrados (lombrices de tierra, termes hormigas. milpiés, ciempiés, arañas, escarabajos, gallinas ruegas, grillos, chicharras, caracoles, escorpiones, chinches y larvas de moscas y de mariposas) pueden incluir más de un millar de especies en un sólo ecosistema y alcanzar densidades y biomasas de más do un millón do individuos y más de una tonelada por hectárea, respectivamente. Estos organismos ejecutan múltiples funciones en el ecosistema y pueden ser divididos en vanas clases, usando diversas clasificaciones funcionales. En México se han muestreado 127 comunidades de macrofauna cdáfica en 37 localidades, principalmente en el estado de Veracruz y en el E y SE del país, usando una metodología estándar (método 'TSBE). Se muestrearon 9 tipos principales de ecosistemas, predominando los pastizales, los bosques y/o selvas, los cultivos anuales, los cítricos y los cafetales. Los resultados preliminares revelaron un predominio de las lombrices do tierra en cuanto a la biomasa en la mayor parte de los ecosistemas, mientras las hormigas predominaron en cuanto a la densidad. Las milpas y el cocotal presentaron la menor biomasa total de lodos los ecosistemas (<15g m2, los bosques tuvieron más de 25 g m2 mientras que los demás ecosistemas se caracterizaron por biomasas mayores de 35 g m2 En la caña de azúcar se encontró un promedio de casi 3000 individuos m2 mientras que en los demás ecosistemas las densidades no fueron mayores de 1600 individuos n2 Como estudio de caso se analizó la región do Los Tuxtlas, en donde se observó que el desmonte de la selva tuvo un efecto negativo en las poblaciones de los artrópodos epigeos, mientras que el implante de pastizales aumentó la biomasa de lombrices, superando inclusive la encontrada en la vegetación original. Finalmente so discute el efecto negativo de la destrucción de los ambientes naturales sobre estos organismos (desaparición de numerosas especies), se resalla la necesidad de taxónomos mexicanos especializados en estos grupos do invertebrados y, debido a su importancia en la agricultura, de mayor cantidad de estudios a nivel de poblaciones y comunidades.

During December 1999, root and stem rot was observed on greenhouse-grown cucumber (cvs. Albatros, Brunex, Acapulco, and Cerrucho) plants in Almería, Spain, using rock wool cultures. The disease caused severe damage, estimated at a loss of up to 75% of the plants, in the first greenhouse affected; afterward, the disease was found in eight additional greenhouses (14 ha) in 1999 and 2000. Stem lesions extended up to 10 to 12 cm above the crown in mature plants, although no fruit damage was observed. In the advanced stages, abundant development of orange sporodochia was evident on crown and stem lesions, without vascular discoloration. Root, crown, and stem pieces that were placed on potato dextrose agar (PDA) after surface-disinfection with 5% sodium hypochlorite, rinsed, and dried resulted in pure fungal colonies. Based on morphological characteristics of conidia, phialides, and chlamydospores from the isolations, the fungus was identified as Fusarium oxysporum Schlechtend.:Fr. Pathogenicity tests were conducted on cucumber (cvs. Marketmore 76 and Cerrucho [F1 hybrid]), melon (cvs. Amarillo oro, Perlita, Piboule, Tania, and Nipper [F1]), watermelon (cvs. Sugar Baby, Sweet Marvel, Jubilee, and Pata Negra and hybrid Crimson sweet), Cucurbita maxima × Cucurbita moschata, zucchini (cv. Senator), and loofah (Luffa aegyptiaca) at several stages: (i) pregermination; (ii) 1 or 2 true leaves; and (iii) more than 10 true leaves. Five fungal isolates were grown on PDA or shaken potato dextrose broth at 25°C for 8 days. Inoculation was performed in pots (10 seeds or plants of each cultivar or hybrid and isolate) by drenching with 100 ml of a fungal suspension (104 to 106 CFU/ml). Sterile water was applied to noninoculated control plants. Tests were repeated in growth chambers at 25°C (night) and 28°C (day) with a 16-h photoperiod. Fifteen to fifty days after inoculation, cucumber and melon plants at all three stages developed symptoms of root and crown rot in 100% of inoculated plants, with no observed vascular discoloration. Fifty days after inoculation, all three stages of C. maxima × C. moschata and zucchini remained symptomless. Loofah and watermelon germinated poorly or not at all when inoculated at the pregermination stage. Fifteen to fifty days after inoculation, 100% of inoculated cucumber and melon plants developed symptoms. Watermelon plants inoculated at the 10 or more true-leaf stage did not develop disease symptoms. No symptoms developed on noninoculated control plants. F. oxysporum was reisolated from infected roots, crowns, and stems of inoculated plants, confirming Koch's postulates. The main symptoms on cucumber infected by F. oxysporum f. sp. cucumerinum are wilt, yellowing, and vascular discoloration. In contrast, based on inoculation of the host differentials and the resulting disease symptoms found in this study, the fungus was identified as F. oxysporum f. sp. radicis-cucumerinum (1). To our knowledge, this is the first report of F. oxysporum f. sp. radicis-cucumerinum causing root and crown rot in cucumber in Spain. Reference: (1) D. J. Vakalounakis. Plant Dis. 80:313, 1996.

Este artículo es el resultado de un esfuerzo colectivo para construir los patrones de distribución de las lombrices de tierra de Colombia a partir del análisis de la información sobre las colectas realizadas entre 1872 y 2003. La información abarca desde registros esporádicos con información taxonómica de las especies hasta estudios sistemáticos de especies en algunas cuencas hidrográficas y en suelos de sabanas, que destacan la alta diversidad en los sistemas de alta montaña de la cordillera de los Andes. El mayor porcentaje (93.2%) de las colectas se ha realizado en la región Andina. La oligoquetofauna colombiana determinada está compuesta por 113 especies situadas en nueve familias, 30 géneros y 6 subgéneros, de las cuales 90 son nativas y 23 exóticas. La mayoría de las especies son endémicas y pertenecen a la familia Glossoscolecidae. Andiodrilus, con 25 especies, fue el género de la familia mejor representado, mientras que Martiodrilus, con 19 especies, ocupó la mayor diversidad de ambientes, desde selvas y pastizales hasta el páramo. Sólo dos especies de esta familia fueron cosmopolitas (Pontoscolex corethrurus y Onychochaeta elegans), las cuales se encontraron en ambientes antropócoros. El resto de las especies de las otras familias fueron euritópicas, excepto Tumak hammeni y Dichogaster medellina.