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Sphagnum mosses are major components of peat bogs but populations of many species are under threat due to habitat fragmentation resulting from the cutting of peat for fuel. We have used an intersimple sequence repeat (ISSR)‐based cloning method to develop nine polymorphic nuclear microsatellites for the peat moss species Sphagnum capillifolium. Between three and seven alleles per locus were detected in a sample of 48 haploid gametophytes and levels of gene diversity ranged from 0.5391 to 0.7960. These represent the first microsatellite markers developed for this important genus and most also exhibited cross‐species amplification across a range of common Sphagnum species. 相似文献
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The fossil salmonid †Eosalmo driftwoodensis was originally described from fragmentary specimens. Study of new material of this fossil species confirms that it is a stem-group salmonine, with a mixture of primitive and derived salmonine features in its skull, but with its postcranial skeleton essentially of modern salmonine construction. Two autapomophies define the genus †Eosalmo: a long anterodorsal process of the subopercle meeting the dorsal edge of the bone at an angle of about 60o , and a thin dermal basihyal plate apparently lacking teeth. Its salmonine relationship is supported by eight derived features: (1) posterior part of frontal widely expanded above autosphenotic, (2) hyomandibular fossa on pterotic long, (3) posterior part of endopterygoid extending posteriorly and broadly overlapped by both metapterygoid and quadrate, (4) premaxillary process of maxilla extending dorsally at an angle larger than 10o , (5) infraorbitals 3 to 5 narrow and covering less than anterior half of hyomandibula, (6) presence of suprapreopercle, (7) anterior end of preopercular canal on horizontal arm distinctiy turning to anteroventral corner of preopercle, (8) first uroneural amplified into large fan-shaped stegural, and (9) scales small, with more fhan two lateral line scales per vertebral centrum. Salmonidae are a monophyletic family defined by at least three synapomorphies: posterior surface of epiotic with sulcus, peg-and-socket connection in caudal skeleton, and tetraploid karyotype. Within the Salmonidae, Thymallinae and Salmoninae form a clade based on features from premaxilla, supramaxilla, anguloarticular, and supraorbital. 相似文献
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