A review on the impacts of feral cats (Felis silvestris catus) in the Canary Islands: implications for the conservation of its endangered fauna

Feral cats have been directly responsible for the extinction of numerous species on islands worldwide, including endemic species of mammals, birds and reptiles. The diet of feral cats in the main habitats of the Canary Islands, as generally occurred on oceanic islands, is mainly composed of introduced mammals, and native species of birds, reptiles and insects. The impact of feral cat upon the endangered species was assessed by evaluating their relative abundance in the cats’ diet and by considering their current conservation status. A total of 68 different preys were identified at species level in all studies carried out in the Canary Islands (5 mammals, 16 birds, 15 reptiles and 32 invertebrates). From all the species preyed by feral cats in the Canary Islands, only four of them are considered threatened by the IUCN Red List of Threatened Species: one endemic bird Saxicola dacotiae and three endemic giant lizards, Gallotia simonyi, Gallotia intermedia, and Gallotia gomerana. Although some efforts on management control have been carried out, it is necessary to enforce these conservation activities on those areas of Tenerife, La Gomera and El Hierro where giant lizards are still present. Furthermore some local areas where endangered bird species are highly predated should be protected. Nevertheless, it is important to take into account the presence of other introduced species such as rats, mice or rabbits in order to avoid problems derived from the hyperpredation process and mesopredator release effect.     

The Genus Obelus Hartmann, 1842 (Gastropoda, Pulmonata, Helicoidea) and its Phylogenetic Relationships

The genus Obelus, so far known from shells only, is re-described on the basis of the anatomy of its genital system. Its range is here restricted to north-western Africa and the Canary Islands. Four species are traditionally listed for the Canary Islands: Obelus despreauxii, O. moderatus, O. mirandae and O. cyclodon. The presence of the last species on the Canary Islands is doubtful, whereas the fossil/subfossil presence of O. pumilio is documented. The species Helix morata also belongs to the genus, as well as a new species, O. discogranulatus sp. nov. The genital systems of all confirmed extant Canarian species are shown. Obelus has a peculiar vaginal stimulator appendix (“appendicula”) which is homologous to the penial appendix of the Orthurethra and to the stimulatory organ of other Stylommatophora, with the exception that the A₃ portion is missing. The genus is diagnosed by characters of the vaginal stimulator appendix, such as a curved, finger-like A₂ portion of the appendicula ending proximally in a blind, well-developed muscular sac, and by the slender tubular A₄ portion arising laterally from the muscular sac duct. We conclude that Obelus belongs to the Cochlicella group because it shares an appendicula with the other genera of the group. However, it differs in anatomical details of this structure. The Cochlicella group should be recognized as a separate family Cochlicellidae Schileyko, 1972, with close relationships to the Helicellidae and the Hygromiidae. A new diagnosis for Cochlicellidae is proposed and its phylogenetic relationships are discussed.This is: Notes on the Malacofauna of the Canary Islands, No. 46.     

烟杆藓属及烟杆藓在中国的新记录

从形态学而论,烟杆藓属(Buxbaumia Hedw.)在苔藓植物中是一个独特的类型。该文简要介绍了烟杆藓属的历史和该属在中国的研究状况,以及该属的模式种烟杆藓首次在中国的发现。对烟杆藓在新疆的着生生境及群落状况做了详细介绍, 还就扫描电子显微镜观察烟杆藓的孢蒴、蒴齿和孢子形态、中国烟杆藓属分种检索表及属的系统关系进行观察和探讨。     

Phylogeography of island canary (Serinus canaria) populations

Island canaries (Serinus canaria) are characterised as a species living exclusively on North Atlantic islands, mainly on the Azores, Madeira and Canary Islands. Although they are very common in their habitats, their behaviour and breeding system has only recently been studied systematically. To advance the understanding of their ecology and to see if the rather isolated archipelagos are already promoting a genetic differentiation, we investigated their phylogeographic relationship as revealed by mtDNA sequences of the cytochrome b gene and investigated whether this measure corresponds to morphological characteristics within the islands. Genetic distances were very low throughout the distribution range of the species. Although the variation of genetic distances within the population of Pico (Azores) was larger than that on Madeira and Canary Islands, the genetic distances between island populations were very low throughout which prevented a clear phylogeographic differentiation. Moreover, morphological measurements did not reveal a consistent pattern to reliably separate the populations, although the measures of beak length and body weight revealed a clear island-specific differentiation. These data lead to the assumption that the colonisation of the Atlantic islands by the canaries occurred very recently, while there is no persisting gene flow between the populations.     

Data on the family Pandalidae around the Canary Islands, with first record of Plesionika antigai (Caridea)

Of the 20 pandalid shrimps species and subspecies reported for the Eastern Central Atlantic (26–36° N), 16 were found in one or more Macaronesian archipelagos (Azores, Madeira, Canary Islands and Cape Verde Islands) (14–40° N), and 11 of them were recorded to date in the Canary Island waters (27° 30–29° 30 N): Bitias stocki Fransen, 1990; Heterocarpus ensifer ensifer A. Milne-Edwards, 1881; Heterocarpus grimaldii A. Milne-Edwards & Bouvier, 1900; Heterocarpus laevigatus Bate, 1888; Plesionika edwardsii (Brandt, 1851); Plesionika ensis (A. Milne-Edwards, 1881); Plesionika holthuisi Crosnier & Forest, 1968; Plesionika martia martia (A. Milne-Edwards, 1883); Plesionika narval (J.C. Fabricius, 1787); Plesionika williamsi Forest, 1964; and Stylopandalus richardi Coutière, 1905. In the present work, Plesionika antigai Zariquiey Álvarez, 1955 is recorded for the first time from the Canary Islands. As a result of many fishing surveys around the Canary Islands at 27–1550 m depth between 1985 and 1998, information on bathymetric distribution, habitat, size and biology of the 12 Canarian pandalid species is given. The geomorphologic, geographic and oceanographic characteristics of the Canary Islands marine ecosystems could explain the great diversity in the biogeographic patterns of the pandalid species inhabiting this area. The distribution patterns found were: Macaronesian (1 spec.), Atlanto-Mediterranean (1 spec.), Eastern Atlantic warm-temperate (1 spec.), amphi-Atlantic warm (2 spec.), amphi-Atlantic warm-temperate (1 spec.), pantropical (5 spec.), and cosmopolitan (1 spec.).     

Phylogeography and genetic structure of the Canarian common chaffinch (Fringilla coelebs) inferred with mtDNA and microsatellite loci

The widespread common chaffinch (Fringilla coelebs) inhabits five of the seven Canary Islands. Sequences of the mitochondrial cytochrome b gene (1002 bp) revealed new insights into the systematics and phylogeography of this taxon. Additionally, a set of microsatellite loci were analyzed to examine the structure of these populations. Our results suggest that a new species of the genus Fringilla is present in the Canary Islands, which comprises at least three subspecies, but with a different distribution to that which has been morphologically accepted. The specimens from Gran Canaria are genetically distinct from those of La Gomera and Tenerife (F. c. canariensis), which suggests the existence of an undescribed taxon. Furthermore, nuclear microsatellite data suggest an ongoing incipient speciation process in this population. This study provides both important conservationist implications and a basis for re-evaluating the taxonomic status of the Canarian Fringilla coelebs populations.     

Complex population genetic structure in the endemic Canary Island pine revealed using chloroplast microsatellite markers

The Canary archipelago, located on the northwestern Atlantic coast of Africa, is comprised of seven islands aligned from east to west, plus seven minor islets. All the islands were formed by volcanic eruptions and their geological history is well documented providing a historical framework to study colonization events. The Canary Island pine (Pinus canariensis C. Sm.), nowadays restricted to the westernmost Canary Islands (Gran Canaria, Tenerife, La Gomera, La Palma and El Hierro), is considered an old (Lower Cretaceous) relic from an ancient Mediterranean evolutionary centre. Twenty seven chloroplast haplotypes were found in Canary Island pine but only one of them was common to all populations. The distribution of haplotypic variation in P. canariensis suggested the colonization of western Canary Islands from a single continental source located close to the Mediterranean Basin. Present-day populations of Canary Island pine retain levels of genetic diversity equivalent to those found in Mediterranean continental pine species, Pinus pinaster and Pinus halepensis. A hierarchical analysis of variance (AMOVA) showed high differentiation among populations within islands (approximately 19%) but no differentiation among islands. Simple differentiation models such as isolation by distance or stepping-stone colonization from older to younger islands were rejected based on product-moment correlations between pairwise genetic distances and both geographic distances and population-age divergences. However, the distribution of cpSSR diversity within the islands of Tenerife and Gran Canaria pointed towards the importance of the role played by regional Pliocene and Quaternary volcanic activity and long-distance gene flow in shaping the population genetic structure of the Canary Island pine. Therefore, conservation strategies at the population level are strongly recommended for this species.Communicated by D.B. NealeA. Gómez and S.C. González-Martínez as joint authors     

Competitive abilities of <Emphasis Type="Italic">Tamarix aphylla</Emphasis> in southern Nevada

Tamarix aphylla is an evergreen tree that has invaded the drawdown zone of Lake Mead, a large reservoir on the Lower Colorado River. We performed competition experiments between T. aphylla and T. ramosissima, and between T. aphylla and the native tree Salix gooddingii. Root:shoot ratios and biomass were higher in S. gooddingii than both Tamarix species, and T. ramosissima grew taller than T. aphylla and S. gooddingii when treatments with single plants and no competition were compared. Tamarix aphylla outcompeted the native S. gooddingii, but had competitive abilities that were slightly inferior to T. ramosissima. The competitive abilities of T. aphylla may and help explain why this species is not as widespread as its congeners, although because of T. aphylla's larger size, the species may be as serious a threat to native riparian ecosystems as T. ramosissima. These results indicate that management actions should be taken to ensure that T. aphylla does not further invade riparian ecosystems in the southwestern United States.     

Phylogeny of the Celastreae (Celastraceae) and the relationships of Catha edulis (qat) inferred from morphological characters and nuclear and plastid genes

The phylogeny of Celastraceae tribe Celastreae, which includes about 350 species of trees and shrubs in 15 genera, was inferred in a simultaneous analysis of morphological characters together with nuclear (ITS and 26S rDNA) and plastid (matK, trnL-F) genes. A strong correlation was found between the geography of the species sampled and their inferred relationships. Species of Maytenus and Gymnosporia from different regions were resolved as polyphyletic groups. Maytenus was resolved in three lineages (New World, African, and Austral-Pacific), while Gymnosporia was resolved in two lineages (New World and Old World). Putterlickia was resolved as nested within the Old World Gymnosporia. Catha edulis (qat, khat) was resolved as sister to the clade of Allocassine, Cassine, Lauridia, and Maurocenia. Gymnosporia cassinoides, which is reportedly chewed as a stimulant in the Canary Islands, was resolved as a derived member of Gymnosporia and is more closely related to Lydenburgia and Putterlickia than it is to Catha. Therefore, all eight of these genera are candidates for containing cathinone- and/or cathine-related alkaloids.     

Microsatellite loci development in endangered pamphagid grasshoppers endemic to the Canary Islands (Orthoptera)

The five recognized endemic pamphagid species (Orthoptera) of the Canary Islands have restricted and fragmented ranges due to habitat decline. Seven polymorphic microsatellite markers have been developed for Acrostira tamarani, and the performance of primer pairs amplifying these loci in related taxa has been tested. The number of alleles in A. tamarani samples taken from two distant localities in the island of Gran Canaria ranged from two to eight per locus. Observed heterozygosities were from 0.151 to 0.559. Up to four primer pairs amplified in related species with moderate heterozigosities (maximum of 0.687 and 10 alleles for Ata67 locus in Purpuraria erna). These markers could be useful tools to study the population structure and management of endemic threatened pamphagids of the Canary archipelago.     

Variation in wild populations of annual beet (Beta,Chenopodiaceae)

Among the morphological variation in wild annual populations of sect.Beta only tepal characters show a geographic pattern, and hence can be used to distinguish different taxa. Two morphological types correspond with taxa already described:B. macrocarpa (incl.B. bourgaei) has a Macaronesian and W. to E. Mediterranean andB. adanensis an E. Mediterranean distribution area. A third type in the Aegean region is not well known yet and possibly has to be included inB. macrocarpa. Both diploid and tetraploid (x = 9) cytotypes are found withinB. macrocarpa, the latter exclusively on the Canary Islands.     

Seasonal response to drought and rewatering in Portulacaria afra (L.) Jacq.

Summary Gas exchange characteristics of droughted and rewatered Portulacaria afra were studied during the seasonal shift from CAM to C₃ photosynthesis. ¹⁴CO₂ uptake, stomatal conductance, and total titratable acidity were determined for both irrigated and 2, 4, and 7.5 month waterstressed plants from summer 1984 to summer 1985. Irrigated P. afra plants were utilizing the CAM pathway throughout the summer and shifted to C₃ during the winter and spring. Beginning in September, P. afra plants shifted from CAM to CAM-idling after 2 months of water-stress. When water-stress was initiated later in the fall, exogenous CO₂ uptake was still measurable after 4 months of drought. After 7.5 months of stress, exogenous CO₂ uptake was absent. The shift from CAM to CAM-idling or C₃ in the fall and winter was related to when water stress was initiated and not to the duration of the stress. Gas exchange resumed within 24 h of rewatering regardless of the duration of the drought. In the winter and spring, rewatering resulted in a full resumption of daytime CO₂ uptake. Whereas during the summer, rewatering quickly resulted in early morning CO₂ uptake, but nocturnal CO₂ uptake through the CAM pathway was observed after 7 days. Gas exchange measurements, rewatering characteristics, and transpirational water loss support the hypothesis that the C₃ pathway was favored during the winter and spring. The CAM pathway was functional during the summer when potential for water loss was greater. Our investigations indicate that P. afra has a flexible photosynthetic system that can withstand long-term drought and has a rapid response to rewatering.     

Ensifer meliloti bv. lancerottense establishes nitrogen-fixing symbiosis with Lotus endemic to the Canary Islands and shows distinctive symbiotic genotypes and host range

Eleven strains were isolated from root nodules of Lotus endemic to the Canary Islands and they belonged to the genus Ensifer, a genus never previously described as a symbiont of Lotus. According to their 16S rRNA and atpD gene sequences, two isolates represented minority genotypes that could belong to previously undescribed Ensifer species, but most of the isolates were classified within the species Ensifer meliloti. These isolates nodulated Lotus lancerottensis, Lotus corniculatus and Lotus japonicus, whereas Lotus tenuis and Lotus uliginosus were more restrictive hosts. However, effective nitrogen fixation only occurred with the endemic L. lancerottensis. The E. meliloti strains did not nodulate Medicago sativa, Medicago laciniata Glycine max or Glycine soja, but induced non-fixing nodules on Phaseolus vulgaris roots. nodC and nifH symbiotic gene phylogenies showed that the E. meliloti symbionts of Lotus markedly diverged from strains of Mesorhizobium loti, the usual symbionts of Lotus, as well as from the three biovars (bv. meliloti, bv. medicaginis, and bv. mediterranense) so far described within E. meliloti. Indeed, the nodC and nifH genes from the E. meliloti isolates from Lotus represented unique symbiotic genotypes. According to their symbiotic gene sequences and host range, the Lotus symbionts would represent a new biovar of E. meliloti for which bv. lancerottense is proposed.     

Genetic bottleneck in invasive species: the potato tuber moth adds to the list

The level of genetic diversity within populations of introduced species has received increasing attention as an important factor influencing their survival and adaptive potential. We examined this issue with the Guatemalan potato tuber moth Tecia solanivora, an agricultural pest which has successfully invaded South America and the Canary Islands within the last 20 years. To analyse changes in T. solanivora genetic diversity, the mitochondrial marker cytochrome b was sequenced from individuals collected across its known distribution area. High haplotypic diversity was observed in Guatemala, whereas only three haplotypes have been found in Venezuela and a single one in the remaining invaded South American countries and the Canary Islands. Invasive haplotypes were not observed in our samples from Guatemala but are closely related to Guatemalan haplotypes. These results are consistent with the hypotheses that (i) either a few individuals were introduced into Venezuela leading to a strong initial genetic bottleneck, or selection pressure may have lead to the disparition of all but a reduced number of introduced haplotypes, (ii) a second bottleneck occured between Venezuela and Colombia, and (iii) the invasion of the Canary Islands originated from South America. We further reviewed the recent literature to compare this change in genetic diversity with those reported for other invasive species. We quantified the changes in genetic diversity between native and introduced ranges for 57 biological invasions. We found that the genetic homogenization in T. solanivora was among the strongest reported and discuss factors that can explain the success of invasive populations with low genetic diversity.     

A new marine interstitial ingolfiellid (Crustacea,Amphipoda, Ingolfiellidea) from Tenerife and Hierro

Ingolfiella canariensis n. sp., from coarse sand and gravel in the mediolittoral zone of Tenerife and Hierro, Canary Islands, is described. The new species shares supposedly apomorphous characters with species from comparable habitats from the Andaman Islands, Bermuda and Curaçao (Netherlands Antilles). The female of Ingolfiella similis Rondé-Broekhuizen & Stock, 1987, from Fuerteventura is also described.     

Peroxidasemuster und Systematik vonArgyranthemum undChrysanthemum s. str. (Asteraceae-Anthemideae)

Leaf extracts of several taxa ofArgyranthemum (nanophaneroand chamaephytes endemic to the Macaronesian Islands) andChrysanthemum s. str. (therophytes of the West Mediterranean region) were subjected to polyacrylamide disc gel electrophoresis and analysis of peroxidase isoenzymes. The differences between the two genera are small; this points to their close affinity. The taxonomic subdivision ofChrysanthemum s. str. is confirmed. ForArgyranthemum the inclusion ofA. callichrysum andA. ochroleucum into sect.Ismelia is suggested.A. foeniculaceum may fit better into the otherwise isolated sect.Monoptera but somewhat approaches sect.Ismelia. Isoenzyme patterns inA. frutescens s. l. seem to reflect a geographical differentiation of the group on 5 Canary Islands.

     

A new species of the interstitial genus <Emphasis Type="Italic">Neopetitia</Emphasis> (Polychaeta,Syllidae, Eusyllinae) from Tenerife,with modified acicular chaetae in males

A new species of Neopetitia San Martín, 2003 is described from intertidal and shallow subtidal soft-bottom stations on the eastern and western coast of Tenerife, Canary Islands. The new species is characterized by the presence in males of a modified acicular chaeta in chaetiger 11. A discussion of known species of the genus is presented.     

A new species of Pseudoniphargus (Crustacea,Amphipoda) from subterranean waters in Tenerife (Canary Islands)

Pseudoniphargus candelariae n. sp. is described from a ground-water-fed well in Tenerife (Canary Islands) and is compared with all species known from Macaronesia. The new species has one unique character (spination of palmar angle of gnathopod 1 sexually dimorphic) and presents furthermore a new combination of morphological features not found in other species of the genus in the area studied.     

Development and characterization of microsatellite markers for the endangered anchialine squat lobster Munidopsis polymorpha

Species of the genus Munidopsis are typically distributed in bathyal and abyssal zones, but the anchialine species Munidopsis polymorpha is an exception. It inhabits a volcanic tube on Lanzarote Island (Canary Islands, NE Atlantic) and is currently listed as endangered due to its highly restricted distribution and degree of endemism. Microsatellite loci were isolated from partial genomic libraries that had been enriched for AC, ACAG, GATA, AAAC and AAG repeat sequences. Eight loci were polymorphic in a sample of 24 individuals. The number of alleles per locus ranged from 2 to 4 with observed and expected heterozygosities ranging from 0.083 to 0.875 and from 0.080 to 0.681, respectively. These markers will be used to evaluate levels of genetic diversity and inbreeding, providing essential information for the development of a management and conservation strategy for this species.     

Xenopsylla spp. (Siphonaptera: Pulicidae) in murid rodents from the Canary Islands: An update

The geographical and host distributions of Xenopsylla fleas parasitizing murid rodents on the Canary Islands have been reported. Three Xenopsylla species, X. cheopis, X. brasiliensis and X. guancha, have been detected on two rodents species, Mus musculus and Rattus rattus. X. guancha has been the most prevalent species detected, specifically on M. musculus, the most abundant rodent, but it has been detected only on three eastern islands, where the species is endemic. X. cheopis has been shown to be the most widely distributed species throughout the archipelago and the species most frequently found on R. rattus. X. brasiliensis has been shown to be the least prevalent Xenopsylla species, with the lowest geographical distribution on the Canary Islands and focused only on R. rattus. The detection of both X. cheopis and X. brasiliensis on the island of Lanzarote, and of X. guancha on the island of Fuerteventura and the islet of La Graciosa represents the first report of these species on those particular Canary Islands.