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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.


Cameron R.A.D.,University of Sheffield | Cameron R.A.D.,Natural History Museum in London | Holyoak G.A.,Quinta da Cachopa | Holyoak D.T.,Quinta da Cachopa | And 3 more authors.
Journal of Conchology | Year: 2013

The genus Atlantica from the Madeiran Islands contains two species, A. gueriniana, endemic on Madeira Island and A. calathoides, endemic to the Desertas. They have been regarded as members of the Discidae. The hitherto unknown genital anatomy of A. calathoides is described here from study of specimens collected on Deserta Grande. Comparisons with Janulus bifrons (Gastrodontidae) from the same island show that they have very similar genital systems, from which it is evident that both species belong to the Family Gastrodontidae. The Discidae of the Canary Islands have been placed provisionally in Atlantica subgenus Canaridiscus. Since the Madeiran Atlantica species are transferred to the Gastrodontidae, Canaridiscus is raised to generic rank in the Discidae. The "accessory duct" connecting penis and oviduct o/Janulus bifrons and Atlantica calathoides (a structure regarded as a unique autapomorphy supporting the monophyly of the Gastrodontidae) is not a duct connection but a transverse bridge.


Campbell C.,Trinity College Dublin | Kelly D.L.,Trinity College Dublin | Smyth N.,National Botanic Gardens | Lockhart N.,Heritage and the Gaeltacht | Holyoak D.T.,Quinta da Cachopa
Journal of Bryology | Year: 2016

Ditrichum cornubicum is a rare and threatened acrocarpous moss found on copper-rich mine waste, characteristic of the EU protected habitat ‘Calaminarian grassland of the Violetalia calaminariae’. The species was once thought to be a British endemic, being known from two former copper/tin mine sites in Cornwall, until the discovery of a population in 2006 at Allihies Mountain Mine, Co. Cork, Ireland, a former copper mine. In light of this discovery, two theories of possible introduction from Britain to Ireland were put forward: (1) an introduction from the 1800s and (2) a more recent introduction (2000s). Only male plants of the species are known, and reproduction and dispersal are therefore solely through asexual propagules and fragmentation. In order to address the conservation questions of the origin of the Irish population and to determine whether diversity exists within this rare species, genetic fingerprinting (amplified fragment length polymorphism) was carried out on the three known global populations. Percent polymorphism was found to be 7.29% and Nei's total gene diversity (HT) was 0.0356. AMOVA revealed that, of the small amount of variation found, the majority was among the three populations (98%). The presence of five private alleles in the Allihies population suggests a longer period of isolation than would fit either theory of introduction. Cluster analyses reveal that the Allihies population is more genetically distinct than the two British populations are to each other, thus heightening the conservation priority for this population. © British Bryological Society 2016


Holyoak D.T.,Quinta da Cachopa | Holyoak G.A.,Quinta da Cachopa
Journal of Conchology | Year: 2012

Two species of Plagyrona are recognised in western-central Portugal, P. placida Sluttleworth and P. angusta sp. nov.; the latter differs in its narrower shell with a smaller umbilicus. The microliabitats of both species are described. P. placida was found in humid woodland with living animals collected mainly from tree trunks and branches, often among mosses, but a few from moss on low rocks. P. angusta occurs in woodland arid also in drier sites wiihfexo trees; it was found living on tree trunks, amongst mosses on loiv rocks and on vertical concrete in a garden. Their geographical ranges overlap and both svecies were found living together at tivo localities.


Holyoak D.T.,Quinta da Cachopa | Holyoak G.A.,Quinta da Cachopa
Journal of Conchology | Year: 2016

Rhysotina (Urocyclidae) is a small genus endemic to the oceanic island of São Tomé in the Gulf of Guinea, off tropical west Africa. It is revised based on shell and spirit specimens collected by the authors in 2013. Two species have been recognised for many years, R. hepatizon (Gould 1845) and R. welwitschi (Morelet 1866). The second of these is shown to have been confused with a third species that is newly described here; they differ in several shell characters and their altitudinal ranges. The genital anatomy is redescribed and figured for all three species, which have similar genitalia despite their distinctive shells. The "unique character" of "a very peculiar structure" of the genital atrium that contributed to naming of the family Rhysotinidae Schileyko 2002 was most likely from a snail that was atypical or distorted in preservation. Nevertheless, because the genus has other peculiarities and the small amount of published molecular data suggest it forms a sister-group to other sampled Urocyclidae, it is tentatively separated from them here as the Subfamily Rhysotininae.


Holyoak D.T.,Quinta da Cachopa | Holyoak G.A.,Quinta da Cachopa
Journal of Conchology | Year: 2012

The genus Ponentina is reviewed. Characters of the distal genital anatomy in addition to shells were studied, allowing recognition of one species in Great Britain (P. subvirescens), two species in France (P. revelata and P. subvirescens) and four known species from the Iberian peninsula (P. platylasia, P. ponentina, P. revelata, P. rosai). In addition, "Trichia" martigena from Andalucia should probably be returned to the genus Ponentina, although generic distinctions between Ponentina and Trochulus are shown to be slight and intergrading. Seven new and apparently endemic species are named and described from Portugal or neighbouring provinces of western Spain. All the known species are redescribed and a key to all European species is presented, using characters from shells and genital anatomy. Nominal taxa from Morocco, Algeria and Tunisia are reviewed, although only shell specimens could be studied and the generic allocation of most of them remains tentative. P. martigena is newly recorded for NW. Africa in N. Morocco. The type localities of F. revelata and P. ponentina are restricted here. Habitats of each of the species are described: all are associated mainly with open sites, often rocky places; eight species are largely restricted to base-poor habitats and tend to have small ranges, often in the mountains; one (P. platylasia) is a strict calciphile; five occur in both basic and base-poor sites, most of the latter having wide geographical ranges. Reduction of the female genitalia is characteristic of most of the species zvhich are restricted to base-poorhabitats, but present in only one of those that occur in more basic places.


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.


Holyoak D.T.,Quinta da Cachopa | Holyoak G.A.,Quinta da Cachopa
Journal of Conchology | Year: 2014

A Portuguese populations of Candidula are reviewed using studies of shells and genital anatomy, based on extensive new collections. 12 species of the genus are recognised, 3 of which are newly described. C. intersecta has often been reported from Portugal, but there are only two confirmed records of established populations, from near Lisbon where it may have been introduced. Other Portuguese material hitherto placed as that species is mostly referable to the cryptic species C. olisippensis or C. belemensis, both of which differ from C. intersecta in having a much longer penial flagellum. C. olisippensis occurs widely in W. and C. Portugal northwards from near Lisbon; it is also newly reported here from NW. Spain, SW. England (Lizard peninsula in Cornwall) and the Azores. C. belemensis from WC. Portugal is very close to C. olisippensis in morphology, although usually larger. They are treated as separate species because they coexist extensively on Serra de Sicó and locally on Monte de Vez. The type locality of C. belemensis is restricted here. C. ponsulensis sp. nov. from EC. Portugal, is another cryptic species very close to C. intersecta in both shell characters and genital anatomy. The widespread C. gigaxii is very local in Portugal, with confirmed recent records only from eastern Alentejo, although subfossil shells have been found in the Algarve. The other species recognised are mainly localised endemics of rocky limestone habitats in Portugal, including two species with sharply keeled shells (C coudensis in S. Beira Litoral; C. setubalensis in the Serra da Arrábida and near Cabo Espichel) and four with rounded shells (C. arrabidensis sp. nov. in the Serra da Arrábida and near Cabo Espichel; C. codia and C. scabiosula in the C. Algarve; C. strucki in the W. Algarve and locally on sand dunes in W. Baixo Alentejo). In addition, C. carrapateirensis sp. nov. is endemic on calcareous coastal sand dunes in the W. Algarve and W. Baixo Alentejo.


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.


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.

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