Buellia laurocanariensis,a new species from the Canary Islands

Abstract:A new corticolous species of Buellia is described from La Palma and La Gomera (Canary Islands). It is mainly characterized by its strongly ornamented, (1–2)–3-septate ascospores with apical and septa thickenings, which follow an ascospore-ontogeny of type B, and its chemistry. The new species is compared with the relatedBuellia lauricassiae (Fée) Müll. Arg. and B. lauricassiaeoides Aptroot. Illustrations of the ascospores of B. laurocanariensis and B. lauricassiaeoides are presented. A habit photograph of the new species is also provided.     

Lecanora sabinae, a new lichen species from the Canary Islands

Lecanora sabinae sp. nov. from the Canary Islands (El Hierro and La Gomera) is characterized chiefly by its greenish thallus with abundant pruinose apothecia ranging in colour from light yellow to almost black. It contains usnic acid, zeorin, and an unknown chemical product SAB-1, is by preference lignicolous and lives in association with the conifer Juniperus phoenicea.     

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.     

Deep-water macroalgae from the Canary Islands: new records and biogeographical relationships

Due to the geographical location and paleobiogeography of the Canary Islands, the seaweed flora contains macroalgae with different distributional patterns. In this contribution, the biogeographical relations of several new records of deep-water macroalgae recently collected around the Canarian archipelago are discussed. These areBryopsidella neglecta (Berthold) Rietema,Discosporangium mesarthrocarpum (Meneghini) Hauck,Hincksia onslowensis (Amsler et Kapraun) P. C. Silva,Syringoderma floridana Henry,Peyssonnelia harveyana J. Agardh,Cryptonemia seminervis (C. Agardh) J. Agardh,Botryocladia wynnei Ballantine,Gloiocladia blomquistii (Searles) R. E. Norris,Halichrysis peltata (W. R. Taylor) P. Huvé et H. Huvé,Leptofauchea brasiliensis Joly, andSarcodiotheca divaricata W. R. Taylor. These new records, especially those in the Florideophyceae, support the strong affinity of the Canary Islands seaweed flora with the warm-temperate Mediterranean-Atlantic region. Some species are recorded for the first time from the east coast of the Atlantic Ocean, enhancing the biogeographic relations of the Canarian marine flora with that of the western Atlantic regions.     

Variation in numbers, territoriality and flock size of a Goldcrest Regulus regulus population in winter

A Goldcrest Regulus regulus population living in a spruce-dominated forest near Oslo (c.60°N), in southern Norway, was studied during the winters (November-March) from 1966–67 to 1971–72. A significant reduction in population size occurred between November and March, the recorded values varying from 76 to 96%, with a mean reduction for all six winters studied of 86%. This winter decline in numbers was significantly correlated with both precipitation (i.e., snowfall) and ambient temperature, but not with bird density. Spiders were the predominant prey items of the Goldcrests, and it is suggested that the birds experience food shortages that affect their survival rate. Although not statistically significant, a mean change in the ratio of males:females from 2:1 in October-November to 10:1 in December—February was observed, suggesting that a greater mortality of females than males occurs during the winter.
Partly based on data for colour-banded birds, it is suggested that the Goldcrests form social flocks, which move around as individual units within territories of about 9 ha (7.5 12 ha, n = 5) in extent. The mean flock size decreased significantly from 4.57 ( n = 157) birds in November-December to 2.82 ( n = 74) birds in January-February, probably because of the reductions in the size of the local population during the winter. The mean flock size in November-December varied inversely with the ambient temperature ( r = -0.92).     

Gerronema wildpretii sp. nov. (Agaricales, Basidiomycetes) a new species from the Canary Islands

Gerronema wildpretii, collected in climactic sites of the monteverde forest of the Canary Islands is described and illustrated. Its macro- and microscopic features delimit this taxon as a new species.     

Song dialects on the Atlantic islands: goldcrests of the Azores ( Regulus regulus azoricus, R. r. sanctae-mariae, R. r. inermis)

Territorial songs in island populations of songbirds are often highly divergent from those of neighbouring continental relatives. This is shown for the three goldcrest subspecies (Regulus regulus azoricus, R. r. sanctae-mariae and R. r. inermis) endemic on six islands of the Azorean archipelago. All investigated populations display a high intra- and inter-individual acoustic variation. On each island, up to six different song types have been found; and a single male sings up to three types. In contrast, all northwestern European populations of R. r. regulus and R. r. anglorum share only a single song type. In playback experiments, none of 18 tested dialect songs of Azorean goldcrests evoked notable territorial reaction in German and Czech goldcrest males (ssp. regulus). Two differing dialect groups of the goldcrest can be distinguished on the Azores. Populations of the eastern islands, São Miguel and Santa Maria, share common song types which are not found on the islands of the central and western groups. Dialect repertoires on the westernmost islands, Flores, Faial and Pico, are dominated by a different song type. In the geologically younger western crater of São Miguel, both western and eastern song types coexist. Acoustic similarities to a population from neighbouring Terceira suggest the western part of São Miguel as the origin for the westward expansion of R. regulus on the Azores.     

Occurrence of the ocean triggerfish in the Eastern Atlantic (Canary Islands)

The occurrence, habitat and abundance are reported for the population of ocean triggerfish Canthidermis sufflamen (Balistidae) at El Hierro, Canary Islands. This is the first record from the Eastern Atlantic.     

New records of bryophytes from the Canary Islands

Abstract

Two members each of the Adelanthaceae and Schistochilaceae and three of the Porellaceae are recorded from Mulanje Mountain, of which Adelanthus lindenbergianus (Lehm.) Mitt., Porella abyssinica (Nees) Trev. var. hoehnelii (Steph.) Pócs, Porella capensis (Gott.) Mitt. and P. subdentata (Mitt.) Steph. are first records for Malawi.     

Adaptive radiation of island plants: evidence from Aeonium (Crassulaceae) of the Canary Islands

The presence of diverse and species-rich plant lineages on oceanic islands is most often associated with adaptive radiation. Here we discuss the possible adaptive significance of some of the most prominent traits in island plants, including woodiness, monocarpy and sexual dimorphisms. Indirect evidence that such traits have been acquired through convergent evolution on islands comes from molecular phylogenies; however, direct evidence of their selective value rarely is obtained. The importance of hybridization in the evolution of island plants is also considered as part of a more general discussion of the mechanisms governing radiations on islands. Most examples are from the Hawaiian and Canarian floras, and in particular from studies on the morphological, ecological and molecular diversification of the genus Aeonium, the largest plant radiation of the Canarian Islands.     

Morphological variability of potato cyst nematodes (Globodera spp.) in the Canary Islands

Thirty populations of potato cyst nematode (Globodera spp.) from the Island of Tenerife and two populations from the UK were assessed for several morphometric and non-morphometric characters thought to discriminate between the species G. rostochiensis and G. pallida. Also 200 cysts from each population were analysed by isoelectric focusing of soluble proteins. Correlation analysis, analysis of variance and principal component analysis were used to investigate relationships between the morphometric characters, how the relationships varied between species and between populations, and which characters were most useful for discriminating between species. The two species differed significantly for each of the four morphometric characters: stylet length, fenestra length, anus-fenestra distance and the number of ridges. The stylet length and fenestra length also showed differences between populations of G. rostochiensis while stylet length and number of ridges showed differences between populations of C. pallida. In general, populations of G. pallida showed greater variation than populations of C. rostochiensis. Principal component analysis of the population means indicated that over 73% of the variation in the characters could be explained by the contrast of stylet and fenestra lengths against the anus-fenestra distance and number of ridges. A plot of the first two principal components separated the two species. Stepwise discriminant analysis provided a linear combination of these four variables which discriminated between the species. Stylet length was found to be the most useful characteristic for distinguishing the species whilst anus-fenestra distance was the least useful.     

A new species of Lepidasthenia (Polychaeta, Polynoidae) from Canary Islands

Lepidasthenia medanensis spn, is described from subtidal sandy bottom and beds of Cymodoceanodosa on the south west coast of Tenerife, Canary Islands.     

Gloeodontia xerophila (Aphyllophorales, Basidiomycota), a new species with corticioid basidioma from the Canary Islands

Gloeodontia xerophila sp. nov. is described and illustrated from material collected on dead xerophyte debris in the Canary Islands. This species is characterized by the odontioid hymenophore with short aculei, up to 2 mm long, dimitic hyphal system and amyloid, subglobose and verrucose spores, 4-5 x 3-4 microm. The new taxon is compared with other species in the genus and a key to the species of Gloeodontia is provided.     

Two new species of Leptus Latreille, 1796 (Trombidiformes: Erythraeidae) from the Canary Islands,parasitising Curculionidae (Insecta: Coleoptera), with new metrical data for some Leptus spp.

Systematic Parasitology - Leptus (Leptus) grancanaricus n. sp. and L. (L.) machadoi n. sp. are described from Gran Canaria and Fuerteventura (Canary Islands). They were collected from new hosts for...     

Three new interstitial dorvilleids (Annelida: Polychaeta) from the Cymodocea nodosa meadows of the Canary Islands

Resource–consumer relationships in Lake Victoria were investigated by use of stable isotope data. ¹³C and ¹⁵N signatures were determined for organisms at a deep (22 m) and a littoral (5 m) site in the Napoleon Gulf near Jinja, Uganda. Results suggest that two food chains operate at the deep site, one leading from a shrimp (Caridina nilotica) to juvenile Nile perch (Lates niloticus), the second leading from zooplankton (copepods and cladocerans) to a cyprinid (Rastrineobola argentea) and lake flies (Chaoborus). Isotopic evidence suggests that shrimp eat suspended particulates and benthos, not crustacean zooplankton or water hyacinth (Eichhornia crassipes). Resource–consumer relationships revealed in this study have implications for understanding future yields of the economically important Nile perch fishery.