Pythium spiculum, a recently described new taxon, has been frequently isolated from declining Quercus rotundifolia and Q. suber roots and rhizosphere since 2003 in southern Iberia. In soils of declining Quercus forests this species was found as frequently as Phytophthora cinnamomi which, until now, was the only oomycete described as a Quercus root rot pathogen in the region. Inoculation tests conducted on young Q. rotundifolia plants showed that Py. spiculum is an aggressive root pathogen, although producing severities of symptoms significantly lower than those of P. cinnamomi. This new pathogen could play a role as decline factor in southern Iberia. Another new species, Py. sterilum, was also found to be pathogenic to Quercus roots but there are presently only few records of this organism isolated from rhizosphere of declining oaks in central Spain. More than an active decline factor, this species should be considered as a potential risk for Quercus forests.

Summary Abies pinsapo, a fir endemic to a small area in southernmost Spain, is frequently attacked in natural stands by Heterobasidion root rot. To identify the Heterobasidion species causing the disease, pure cultures of the fungus were isolated from symptomatic trees in five localities in Sierra de las Nieves Natural Park and identified by pairing tests. In addition, genets of the fungus were identified in two pure stands of A. pinsapo. All the Heterobasidion specimens collected belonged to the species Heterobasidion abietinum. The largest genet found was 57 m long, and had colonized 10 trees. The large size of the main genets implied that H. abietinum had spread via root contacts from old infections generated before the establishment of the Sierra de las Nieves National Park in 1989. Exceptionally dry summers in the last 20 years may have weakened A. pinsapo and favoured spread of the disease.

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A previously undescribed meteorite crater having dimensions of 455 m average diameter and 31 m average depth has been discovered in northern Chile at 23ø55.6'S, 68ø16.7'W. Meteorites have not been recovered, but iron shale and impactite material verify its meteoritic origin. The crater is eraplaced in granite, overlain by a thin ignimbrite sheet. From the apparent disruption of the local Pleistocene drainage pattern, the age of formation of the crater must be Pleistocene or Recent. It may have been formed by the same meteoroid that created the Campo del Cielo craters in Argentina. The name Monturaqui crater is proposed.The diameter of the crater is 470 m E-W X 440 m N-S. The wall height is very variable, ranging from 16 to 48 m above the low point. The variable wall height was probably caused by topographic irregularities in the pre-impact surface. The low point, seen in the aerial photograph as a white spot of fine clay and silt, is off-center toward the northeast; thus the crater is somewhat asymmetric.

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