The first fossil spider cricket (Orthoptera: Gryllidae: Phalangopsinae): 20 million years of troglobiomorphosis or exaptation in the dark?

A new spider cricket (Orthoptera: Gryllidae: Phalangopsinae) is described from an adult female preserved in Early Miocene (Burdigalian) amber from the Dominican Republic. Araneagryllus dylani gen. et sp. nov. represents the first fossil record of Phalangopsinae, and is assigned to the tribe Luzarini, subtribe Amphiacustina stat. nov. A cladistic analysis of Amphiacustina places Araneagryllus gen. nov. within a clade comprising Arachnopsita, Leptopedetes, Longuripes, Mayagryllus, Nemoricantor, and Prolonguripes. This clade is the sister group to a clade comprising Amphiacusta, Cantrallia, and Noctivox. The results of this analysis suggest that: (1) the common ancestor of all Amphiacustina was epigean, and was likely to have been cavicolous and/or straminicolous; (2) strict troglobitism evolved twice within Amphiacustina, once in the lineage leading to Noctivox and again in the clade comprising Mayagryllus, Arachnopsita, Longuripes, and Prolonguripes; and (3) Prolonguripes is secondarily epigean, having reverted to life above ground. The occurrence of Araneagryllus gen. nov. in amber indicates that it was not troglobitic, but was instead more likely to have been straminicolous, living on the ground and foraging amongst leaf litter. Araneagryllus gen. nov. possesses a number of characters that are usually considered to be adaptive to a troglobitic life history, suggesting that many so‐called troglobiomorphies are not adaptations to life in caves, but are instead likely to have been exaptive. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 56–65.     

Electric fishes of the genus Sternarchorhynchus (Teleostei,Ostariophysi, Gymnotiformes); phylogenetic and revisionary studies

Analysis of 88 characters of external and internal body systems yielded a phylogenetic reconstruction of the Neotropical electric knifefish genus Sternarchorhynchus (Apteronotidae; Gymnotiformes). The results support a hypothesis of Sternarchorhynchus as the sister group to Platyurosternarchus. A series of synapomorphies, many involving major innovations of the neurocranium, jaws, suspensorium, and associated systems that permit an unusual mode of grasp‐suction feeding, support the monophyly of both genera. Synapomorphies largely resolve relationships within Sternarchorhynchus with basal nodes strongly supported by characters pertinent to prey capture and initial processing of food items. These possible key innovations may provide Sternarchorhynchus with a competitive advantage over other clades of the Apteronotidae and account for the species diversity of the genus in Neotropical rivers. Adaptive radiation in Sternarchorhynchus was analysed. Habitat preference transitions repeatedly occurred in the genus between deep‐river channel dwelling species and rheophilic species with preferences for higher energy setting including rapids and swift‐flowing fluviatile settings. Twenty‐two species of Sternarchorhynchus are described as new based on samples that originated in the smaller rivers draining into the Golfo de Paria, the Marowijne and Essequibo River basins, the Río Orinoco and in particular the Amazon River basin. The 32 species in Sternarchorhynchus make it the most speciose genus in the Apteronotidae. No claim to original US government works. Journal compilation © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 223–371.     

Comparative vegetative anatomy and systematics of the angraecoids (Vandeae, Orchidaceae) with an emphasis on the leafless habit

The vegetative anatomy and morphology of 142 species of the angraecoid orchids (Angraecinae + Aerangidinae) and 18 species of Aeridinae were examined using light and scanning electron microscopy. Leafless members of Vandeae were of particular interest because of their unique growth habit. Leafy and leafless members of Angraecinae and Aerangidinae were examined and compared with specimens of Aeridinae. Vandeae were homogeneous in both leaf and root anatomy. A foliar hypodermis and fibre bundles were generally absent. Stegmata with spherical silica bodies were found associated with sclerenchyma and restricted to leaves in almost all specimens examined. Distinct inner tangential wall thickenings of the endovelamen occurred in several vandaceous genera. Exodermal proliferations and aeration units commonly occurred in both leafy and leafless Vandeae. Cladistic analyses of Angraecinae and Aerangidinae with members of Aeridinae and Polystachyinae as outgroups using 26 structural characters resulted in 20 000+ equally parsimonious trees. Vandeae formed the only well-supported clade in bootstrap analyses and were characterized by having a monopodial growth habit, spherical stegmata, loss of mucilage, and loss of tilosomes.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 165–218.     

A classification of Danaus butterflies (Lepidoptera: Nymphalidae) based upon data from morphology and DNA

Classification of the cosmopolitan butterfly genus Danaus (Nymphalidae: Danainae) is revised at subgeneric, specific and subspecific levels, combining for the first time mitochondrial and nuclear DNA sequence information with morphological data. Tree topologies based on the nuclear genome (allozymes, pheromone components, the morphology of all life history stages and nuclear DNA sequences), on the one hand, and mitochondrial DNA, on the other, are incongruent and challenge the current taxonomy of the genus. Although earlier classifications, based on adult morphology alone, are, in general, well supported by an analysis of total evidence, the mitochondrial phylogeny shows that the species D. chrysippus and its subgenus Anosia are deeply paraphyletic. Subspecies dorippus of D. chrysippus is the basal clade of the genus and is reinstated as the species D. dorippus. The former species D. plexaure is demoted to a subspecies of D. eresimus. The specific status of D. erippus, as distinct from D. plexippus, is tentatively supported. On the strength of the new data, division of the monophyletic genus Danaus s.l. into three subgenera Danaus s.s., Salatura and Anosia is unsustainable and is abandoned. Of the 15 terminal clades (taxa) of Danaus s.l. included in the study, 11 are species that broadly conform to the biological species concept. (The West Indian species D. cleophile, missing from our analysis, is the twelfth species). The remaining terminal clades are subspecies of D. chrysippus comb. nov. and D. dorippus stat. rev. Two sympatric Neotropical species, D. eresimus and D. gilippus, are morphologically distinct and sexually isolated but have nearly identical mitochondrial genomes. In contrast, two partially sympatric Palaeotropical species, D. chrysippus and D. dorippus, are cryptic species that share structural morphology and hybridize but have highly differentiated mitochondrial genomes. D. dorippus is polymorphic for two anciently diverged haplotypes and its history has possibly involved recombinational speciation and/or hybridism. © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society, 2005, 144 , 191?212.     

The fern genus Elaphoglossum section Lepidoglossa (Dryopteridaceae) in Africa,Macaronesia, the mid‐Atlantic and southern Indian Ocean Islands

Elaphoglossum section Lepidoglossa in Africa, Macaronesia (Azores and Madeira), the mid‐Atlantic Ocean Islands (St Helena, Gough and Tristan da Cunha Island groups) and the southern Indian Ocean Islands (Marion and Prince Edward Islands) is reviewed. Fifteen Elaphoglossum species from this region are ascribed to the section. A new species, Elaphoglossum rivularum , confined to the Chimanimani Mountains in eastern Zimbabwe and formerly ascribed to E. kuhnii from West Africa, is described. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 20–63.     

Reassessment of the Lower Cretaceous (Barremian) pliosauroid Leptocleidus superstes Andrews, 1922 and other plesiosaur remains from the nonmarine Wealden succession of southern England

The Lower Cretaceous (upper Berriasian to lowermost Aptian) nonmarine Wealden succession of southern England has been a prolific source of vertebrate fossils for over 180 years. The sequence is most famous for terrestrial reptiles, particularly dinosaurs; however, significant aquatic tetrapod discoveries including rare nonmarine plesiosaurs have also been reported. The record of Wealden plesiosaurs currently incorporates a single valid taxon, Leptocleidus superstes Andrews, 1922a, based on a partial skeleton and skull from the Barremian Upper Weald Clay Formation of Berwick, Sussex. Traditional classifications place this plesiomorphic pliosauroid with basal Jurassic rhomaleosaurids; however, the genus Leptocleidus has since become a ‘waste basket’ for various Cretaceous rhomaleosaurid‐like plesiosaurs from around the globe. In an attempt to clarify this situation, the type specimen of L. superstes was reexamined and redescribed. Previously unrecorded anatomical features were identified including an elongate, gracile paraoccipital process on the exoccipital‐opisthotic, and tooth ornament comprising widely spaced, coarse striations that are restricted to the lingual surface of the crown (mesiodistal ‘carinae’ are absent). Other indeterminate pliosauroid remains (recovered along with coeval elasmosaurids) from the upper Berriasian–Valanginian Hastings Beds Group also exhibit potentially diagnostic traits: an atlas centrum with no anterolateral exposure and with ventral margin formed by the intercentrum; a single‐headed rib articulation on the atlas centrum extending onto the axis centrum; and epipodials that are longer than broad. The placement of L. superstes is controversial in recent phylogenies. To test the competing hypotheses, L. superstes together with all closely related species were rescored into the most comprehensive published phylogenetic data sets of Plesiosauria and Pliosauroidea. Separate maximum parsimony and Bayesian analyses of each matrix unanimously supported a relationship between L. superstes and pliosauroids but could not confirm placement within either Rhomaleosauridae sensu stricto, or a discrete ‘leptocleidoid’ clade. Examination of character states advocating affinities amongst Leptocleidus spp. suggests homoplasy rather than clear homology between what are potentially palaeobiogeographically disparate genus‐level taxa. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161 , 663–691.     

Phylogenetic relationships in Cyperus L. s.l. (Cyperaceae) inferred from plastid DNA sequence data

The phylogeny of Cyperus and allied genera has been reconstructed using cladistic analysis of plastid rbcL gene, rps16 intron, trnL intron, and trnL-F intergenic spacer sequence data in 40 species of tribe Cypereae. Cyperus s.s. as currently circumscribed is not monophyletic because ten cyperoid genera are embedded within it. Eucyperoid Cyperus species (with a C₃ anatomy, e.g. C. involucratus ) and the genera Courtoisina , Kyllingiella and Oxycaryum form a clade that is sister to a clade comprising chlorocyperoid species (with a C₄ anatomy, e.g. C. papyrus ) and the genera Alinula , Ascolepis , Kyllinga , Lipocarpha , Pycreus , Remirea and Sphaerocyperus . The position of two species is uncertain; C . tenellus is resolved in a clade together with Isolepis although with typical cyperoid spikelets, whereas I. humillima is not resolved near either Isolepis or Cyperus s . l . © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 138 , 145–153.     

Occurrence of tetraploid and octoploid cytotypes in Senecio jacobaea ssp. jacobaea (Asteraceae) in Pannonia and the Carpathians

Four different cytotypes have been reported for Senecio jacobaea L. ssp. jacobaea throughout Europe, with the most common occurrence of tetraploids (2 n  = 40). Here we present a survey of previously published chromosome number data on this subspecies and its geographical distribution, and focus on populations from Pannonia and the Carpathians. Two ploidy levels have been determined in the study area, using chromosome counting and flow cytometry: tetraploid (2 n  = 40) and octoploid (2 n  = 80). Fifty-one populations originating from Slovakia, Austria, the Czech Republic, Hungary, Ukraine and Romania have been analysed. Multivariate morphometric analyses have been performed on 39 populations to study morphological differentiation between these two cytotypes. Despite slight morphological tendencies expressed on the level of populations, tetraploid and octoploids cannot be reliably distinguished morphologically and they are not taxonomically classified formally here.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153 , 231–242.     

The Rubiaceae of São Tomé e Príncipe (Gulf of Guinea): taxonomy and conservation

A synoptic treatment of the Rubiaceae of São Tomé e Príncipe (Gulf of Guinea) is presented based on herbarium collections kept at BM, COI, K and LISC. There are 36 genera and 64 species of Rubiaceae represented in the flora of São Tomé e Príncipe. Identification keys are provided for genera, species and infraspecific taxa. A new combination is made in Chassalia . Twenty-nine taxa are endemic to these islands, two of which are also endemic to Annobon. The conservation status of the endemic taxa is assessed and IUCN categories of threat are proposed for ten taxa. Nineteen taxa of Rubiaceae are considered under threat in São Tomé e Príncipe and ten are considered nearly threatened.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 85–114.