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Holyoak D.T.,Quinta da Cachopa | Kockinger H.T.,Roseggergasse 12
Journal of Bryology | Year: 2010

The taxonomy of Anomobryum julaceum and allied species with axillary bulbils in Europe and Asia is reviewed. A. concinnatum is regarded as a distinct species, occurring in W. and C. Europe, SW., N. and C. Asia and N. America. A. bavaricum has often been confused with A. concinnatum, but differs in its more numerous, small, reddish bulbils and in leaf shape; it is known only from the European Alps. The Asian A. nitidum also has numerous small reddish bulbils but it differs from A. bavaricum in leaf shape and bulbil form. A lectotype is designated for A. nitidum, of which A. gemmigerum and other nominal taxa are regarded as synonyms. Information is presented on geographical ranges and habitats of the four valid species. © 2010 British Bryological Society. Source


Holyoak D.T.,Quinta da Cachopa
Journal of Bryology | Year: 2010

Taxonomy of some European species of Ephemerum is reviewed. As in several other recent studies, E. minutissimum Lindb. is regarded as a distinct species from E. serratum (Hedw.) Hampe; it is recorded from N. America (by the newly designated lectotype and other specimens) and Turkey, in addition to Europe. E. serratum var. angustifolium Bruch & Schimp. may be a synonym of E. minutissimum; the costate forms E. serratum var. praecox A.W.H.Walther & Molendo and E. intermedium Mitt. in Braithw. are treated as synonyms of E. serratum s.str. Type specimens of E. stellatum H.Philib. are described, a lectotype is designated and it is placed as a synonym of E. serratum s.str. E. hibernicum Holyoak & V.S.Bryan is regarded as a synonym of E. rutheanum Schimp. in Ruthe. The latter is shown to be a rare, European endemic taxon with modern records from Ireland, S. Wales, Germany and The Netherlands, and old records from France and W. Poland; a lectotype is designated. Forms intermediate between E. sessile (Bruch.) Müll.Hal. and the N. American E. crassinervium (Schwägr.) Hampe occur in several countries in W. Europe, some of them indistinguishable from some of the American plants; forms intermediate between E. sessile and E. rutheanum are recorded from S. Portugal and (rarely) Ireland. Differences between E. crassinervium, E. sessile and E. rutheanum in characters of leaves, tubers and capsules are shown to be slight, with considerable overlap. Hence all three taxa are treated as subspecies of E. crassinervium. A revised key to European Ephemerum and Micromitrium is presented. © 2010 British Bryological Society. Source


Holyoak D.T.,Quinta da Cachopa | Holyoak G.A.,Quinta da Cachopa | Santana J.,University of Las Palmas de Gran Canaria
Journal of Conchology | Year: 2016

Vermetum festinans was hitherto known only from a few shells collected on La Palma. It is the type species of Vermetum, which has sometimes been classified in the Pristilomatidae. The recent allocation of a second species newly discovered on Gran Canana, V. tamadabaensis, to the same genus zvas based only on close similarity of its shells to those of V. festinans. The genus zvas transferred to the Gastrodontidae from the Pristilomatidae on the basis of characters of the genital anatomy shown by V. tamadabaensis. Efforts to refind living V. festinans were successful in 2015, allowing the redescription here of its shells and habitat and the first studies of its genital anatomy. It closely resembles V. tamadabaensis anatomically, sharing the presence of a sarcobelum and three "bridges" joining parts of the distal genitalia, differing only in details. The new data therefore confirm that the genus Vermetum should be transferred to the Gastrodontidae and that two species should be recognised. Source


Willing M.J.,4 Goodwood Close | Holyoak D.T.,Quinta da Cachopa | Holyoak G.A.,Quinta da Cachopa
Journal of Conchology | Year: 2014

Myxas glutinosa was feared extinct at all of its British sites for several years before it was rediscovered in Llyn Tegid (North Wales) in 1998. Results of a study of this population over eleven years are described in this paper. At Llyn Tegid it is restricted to the littoral zone, occurring exclusively beneath boulders and other large stones in silt-free areas. Unlike some populations in Ireland where it does not hide under rocks, the snails occur at low densities, and compared to these and many of the extinct British populations they are small when mature (shell height rarely reaching 10 mm). Repeated sampling of populations for biometrical study suggested that M. glutinosa has an annual life cycle in the lake, with snails reaching full size and reproductive maturity in late winter or spring, shortly before their death. The possible significance of sudden changes in the water-level of Llyn Tegid and its toxic algal 'blooms' for the conservation of M. glutinosa are discussed. Source


Alonso M.R.,University of La Laguna | Holyoak D.T.,Quinta da Cachopa | Holyoak G.A.,Quinta da Cachopa | Yanes Y.,University of Cincinnati | Ibanez M.,University of La Laguna
Journal of Conchology | Year: 2013

The genital anatomy is described for all five island populations of Retinella (Lyrodiscus) endemic in the Canary Islands, revealing that it is mainly similar to that of the only species studied previously (R. circumsessa). Their shell characters, detailed distribution and habitat preferences are also described and reassessed. Five species are recognised. The population of El Hierro has hitherto been assigned to R. lenis, the species on La Palma, but it is named as a new species here. Descriptions of species from the south-west Alps by Giusti et al. (1986) revealed additional combinations of anatomical and shell characters that made it impossible to identify the limits of subgenera among the European Retinella species. Lyrodiscus was regarded by them as a possible exception to this because of its peculiar shell sculpture. Since our data show that the endemic Canary Islands species assigned to Lyrodiscus from conchological characters are also very similar to each other anatomically, it is useful to retain them together in the same subgeneric group until a phylogenetic study provides an adequate basis for a revised classification. Two additional Lyrodiscus species showing the characteristic shell sculpture are known from fossils in NW. Europe. Hence, it is argued that the species still living in the Canary Islands can most easily be regarded as relicts of a fauna that was widespread in NW. Europe in the Neogene and early Pleistocene. There, they apparently became extinct during the cold conditions of the Late Pleistocene glacial stages, whereas they survived in the milder climates within forest and scrub-covered habitats on the Canary Islands. Source

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