The bark and ambrosia beetles (Curculionidae, Scolytinae) of Cocos Island, Costa Rica and the role of mating systems in island zoogeography

Cocos Island is a small oceanic island midway between Costa Rica and the Galápagos Archipelago; about 2 Myr in age, it is the only tropical oceanic island in the eastern Pacific with tropical wet forest. We identified several hundred bark beetle specimens collected during recent expeditions by INBio, the National Biodiversity Institute of Costa Rica, and re-examined all specimens from earlier collections. We report 19 species in ten genera, seven or eight of which are endemic, making scolytines the largest group of beetles known from the island. We describe as new Pycnarthrum pseudoinsulare , Xyleborinus cocoensis , and Xyleborus sparsegranulosus , resurrect Xyleborus bispinatus as separate from X. ferrugineus , and report six other species as new to Cocos Island. Three-quarters of the scolytines reproduce by brother–sister mating, and we argue that inbreeders are superior island colonists because they are less affected than are outbreeders by problems of mate location and inbreeding depression. The fauna and flora of Cocos Island arrived by dispersal and human transport. We examine natural colonization patterns for the fauna, using the distributions of the relatives of island endemics: most colonization came from the Americas, but the closest relatives to some endemics are found on Caribbean or Galápagos islands. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 729–743.     

The Neotropical species of Drapetis Meigen (Diptera: Empididae)

Abstract The Neotropical species of Drapetis Meigen are reviewed, and eight new species are described: alimacula , from Trinidad; atrinervalis , from Bahamas; naevia , from El Salvador; onconeura , from Costa Rica; steyskali , from Mexico; stictica , from Jamaica; tibialis , from Panama; and tuberculata , from Costa Rica. A lectotype is designated for Drapetis divergens Loew; Drapetis intermedia Smith is newly synonymized with divergens Loew. Two new species groups are described, the divergens group and the naica group. Two keys are provided: one distinguishing the Neotropical species of Drapetis ; the other distinguishing Drapetis Meigen, Crossopalpus Bigot and Elaphropeza Macquart. Drapetis flavicornis Melander, inermis Melander and zonalis Curran are assigned to Elaphropeza Macquart, new combinations, and redescribed. The heretofore unknown male of Elaphropeza flavicornis is described.     

Species richness and structure of three Neotropical bat assemblages

We compared the assemblages of phyllostomid bats in three Neotropical rainforests with respect to species richness and assemblage structure and suggested a method to validate estimates of species richness for Neotropical bat assemblages based on mist-netting data. The fully inventoried bat assemblage at La Selva Biological Station (LS, 100 m elevation) in Costa Rica was used as a reference site to evaluate seven estimators of species richness. The Jackknife 2 method agreed best with the known bat species richness and thus was used to extrapolate species richness for an Amazonian bat assemblage (Tiputini Biodiversity Station; TBS, 200 m elevation) and an Andean premontane bat assemblage (Podocarpus National Park; BOM, 1000 m elevation) in Ecuador. Our results suggest that more than 100 bat species occur sympatrically at TBS and about 50 bat species coexist at BOM. TBS harbours one of the most species-rich bat assemblages known, including a highly diverse phyllostomid assemblage. Furthermore, we related assemblage structure to large-scale geographical patterns in floral diversity obtained from botanical literature. Assemblage structure of these three phyllostomid assemblages was influenced by differences in floral diversity at the three sites. At the Andean site, where understorey shrubs and epiphytes exhibit the highest diversity, the phyllostomid assemblage is mainly composed of understorey frugivores and nectarivorous species. By contrast, canopy frugivores are most abundant at the Amazonian site, coinciding with the high abundance of canopy fruiting trees. Assemblage patterns of other taxonomic groups also may reflect the geographical distribution patterns of floral elements in the Andean and Amazonian regions.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 617–629.     

A new species of Selaginella from Hainan Island, China, with a key to the Hainan species

Selaginella hainanensis X.C.Zhang & Noot. sp. nov. , a new species from Hainan Island, South China, is described and illustrated. Diagnostic notes and a key to the species distributed in Hainan are also provided.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 323–327.     

Delturinae, a new loricariid catfish subfamily (Teleostei, Siluriformes), with revisions of Delturus and Hemipsilichthys

A new subfamily, Delturinae, is described to accommodate the loricariid catfish genera Delturus Egenmann & Eigenmann, 1889 and Hemipsilichthys Eigenmann & Eigenmann, 1889, a clade recently demonstrated to be the sister group of all remaining loricariids except Lithogenes . The genus Hemipsilichthys is restricted to three species, H. gobio (Lütken, 1874), its sister species H. papillatus Pereira et al ., 2000, and H. nimius Pereira et al ., 2003. Relationships among species of Delturus were not resolved and a new species, D. brevis , is described from the Rio Jequitinhonha basin in eastern Brazil. The geographical distribution of Delturinae, exclusively on the south-eastern Brazilian Shield, indicates that south-eastern Brazil acts as either a refugium for basal loricariid taxa or a point of origin for the Loricariidae. Lectotypes are designated for D. parahybae Eigenmann & Eigenmann, 1889 and Plecostomus angulicauda Steindachner, 1877. Keys are presented for subfamilies of Loricariidae and for genera and species of Delturinae. Diagnoses are provided for all delturine clades and species.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 277–299.     

A preliminary survey of the Chironomidae (Diptera) of Costa Rica,with emphasis on the lotic fauna

Extensive collections of Chironomidae were made in Costa Rica, Central America, during 1986 and 1987. Fifty-five genera and at least 148 species belonging to the subfamilies Podonominae, Tanypodinae, Orthocladiinae and Chironomidae were found. Chironominae and Orthocladiinae predominated. Only one species of Podonominae was collected. Tanypodinae was represented by many genera, but species richness was low.Cricotopus was the most widespread and diverse genus of Orthocladiinae. Among the Chironominae the generaPolypedilum, Pseudochironomus, Tanytarsus andRheotanytarsus showed high species richness. Several species were collected that could not be assigned to genus. A number of range extensions were recorded for taxa found in the Neotropical region for the first time and for Neotropical taxa recorded outside of South America for the first time. The Costa Rican chironomid fauna consists of cosmopolitan, holarctic and neotropical components. There is probably an endemic Central American chironomid fauna at the species level.     

Teucrium francoi M. Seq., Capelo, J.C. Costa & R. Jardim, a new species of Teucrium gr. scorodonia (Lamiceae) from Madeira

The species formerly recognized as Teucrium scorodonia in Madeira is here described as new: Teucrium francoi M. Seq., Capelo, J.C. Costa & R. Jardim. Morphologically close to species of Teucrium gr. scorodonia [ T. scorodonia L., T. pseudoscorodonia Desf., T. siculum (Raf.) Guss. and T. kotschyanum Poech], it exhibits, nonetheless, some distinct diagnostic characters. The indumentum density and type of hairs of T. francoi are clearly distinct from those of related species, as are the shape and dimensions of the leaves and bracts, calyx, and corolla, which are all taken as taxonomically significant diagnostic features. A diagnosis and a distribution map are presented for this new species. Morphology, ecology, biogeography, and conservation issues are discussed. Teucrium francoi , which is an endemic from Madeira (Portugal), is to be found mostly in the scope of the association Teucrio francoi–Origanetum virentis J.C. Costa, Capelo, Jardim, Sequeira, Lousã & Rivas-Martínez, but also occurs in somewhat humid habitats, such as open stands of Rosa mandonii Déségl. associated with small streams.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 639–647.     

A seasonal evergreen forest in Belize: unusually high tree species richness for northern Central America

Most of the undisturbed forests of northern Central America remain undescribed. Some studies predict that tree species richness in lowland forests of northern Central America should be much lower than in similar forest types in southern Central America. This paper describes the physical and biological structure of two permanent, one-hectare plots on a valley floor in the Bladen Nature Reserve, Belize and compares these plots with other forests in the Neotropics. The plots have 91 and 89 species of trees ≥ 10 cm diameter (327 and 358 individuals, respectively) and comparable or higher measures of alpha-diversity than other such forests in Central America. The recorded tree species richness from other forests in northern Central America may be lower than those in southern Belize. The plots are dominated by Mortoniella pittieri Woodson (Apocynaceae), a disjunct from Costa Rica and Nicaragua. More than 50% of the tree species have distributions ranging into Bolivia or Peru, and >75% are wide-ranging species. The plots have a lower tree density and a higher proportion of large trees (>70 cm dbh) than other wet Neotropical forests. Like other Neotropical forests, tree species in the plots are generally aggregated and have a high proportion of vertebrate-dispersed fruits. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 138 , 275–296.     

A new species of Acantholimon Boiss. sect. Glumaria Boiss. (Plumbaginaceae) from Elazığ, Turkey

A new species, Acantholimon evrenii sp. nov. is described and illustrated for the first time in sect. Glumaria from Turkey. The species is confined to B7 Elazığ in East Anatolia where it grows on rocky mountain steppes. The diagnostic morphological characters from closely related species are given, along with a discussion dealing with its taxonomic relationship. Its conservation status is indicated. A revised key is also provided for the Acantholimon species with heterophyllous leaves, two or more flowered and four or more bracteated spikelets.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 351–356.     

Relationships between drosophilids (Diptera, Drosophilidae) and the environment in two contrasting tropical vegetations

Although natural populations of drosophilid flies have been the subject of ecological studies, the population ecology of these insects in the tropics is still poorly known. This paper discusses aspects of the relationship between drosophilids and their environment, based on 28 monthly collections made in two contrasting vegetations of the Brazilian Cerrado biome: gallery forest and savanna. Exotic species were found in both types of environment; but 14 of the 30 captured Neotropical species occurred exclusively in the gallery forests, probably because of their climatic stability and greater environmental heterogeneity. Even though some endemic species were more abundant in the dry and cold months, most populations exhibited peaks of abundance in the wet season. The species diversity indexes (H' and D), higher in the dry season, were probably affected by increased evenness at this time of year, when the populations of practically all the species are greatly reduced. As species richness in the savanna vegetation clearly decreased in the dry season, increasing again in the wet season, it is suggested that some drosophilids migrate to the forests when climatic conditions are too stressful in the savannas.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 87 , 233–247.     

Development, phylogeny, and taxonomy of Bostrycapulus (Caenogastropoda: Calyptraeidae), an ancient cryptic radiation

Calyptraeid gastropods are well know for the taxonomic difficulties caused by their simple, phenotypically variable shells. In this paper I demonstrate that what was previously considered to be a single species, Crepidula aculeata , is an ancient (3–15 Myr) cryptic species complex made up of at least eight species, and that this group should be placed in the genus Bostrycapulus . Despite the difficulty in finding diagnostic adult shell and anatomical features upon which species can be unambiguously identified, DNA sequences, protoconch morphology, embryonic morphology and developmental characters clearly differentiate these eight species. A single species with direct development and nurse eggs is present in the South Atlantic, and a species with planktotrophic development occurs in the equatorial Pacific. The species from Japan, Australia, Florida, the Pacific coasts of Mexico and Central America, and the Cape Verde Islands all have direct development. Most of these species are separated by > 15% divergence in COI sequence data. The fossil record of Bostrycapulus goes back to the Miocene, which agrees with genetic estimates of divergences within the genus ranging from 3 to 15 Mya. Surprisingly, these ancient species differ only slightly in morphology from each other and genetic differentiation does not correlate with geographical distance. I revise the genus Bostrycapulus on the basis of differences in adult morphology, embryonic morphology, mode of development, protoconch morphology, and DNA sequence data. I also describe four new species ( B. pritzkeri sp. nov., B. odites sp. nov., B. latebrus sp. nov. and B. urraca sp. nov. ) and remove three others ( B. gravispinosus , B. calyptraeformis , and B.  cf. tegulicius ) from synonymy with B. aculeatus .  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 75−101.     

A new species of Viola L. (Violaceae) from Sichuan, China

Viola muliensis Y.S. Chen & Q.E. Yang, a new species of Viola L. (Violaceae) from Sichuan, China, is described and illustrated. Viola muliensis is endemic to Muli County, south-western Sichuan. This new species has yellow flowers with very short spurs and belongs to subsection Brevicalcaratae W. Beck., section Dischidium Ging. It is distinguished from other related species by having pedatipartite leaves.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 365–368.     

A new species of Oxalis section Corniculatae (Oxalidaceae) from the Balearic islands

A new species, Oxalis ferae Llorens, Gil & Cardona (Oxalidaceae) from the Balearic islands (Spain) is described and illustrated. It is considered to be endemic to Mallorca. The morphological differences between the more closely related taxa of Oxalis section Corniculatae are discussed. IUCN threatened category and observations on the ecology of the populations are noted.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 489–493.