Multivariate analyses of morphological characters of Leptolaena Thouars s.l. subgenera Mediusella and Xerochlamys (Sarcolaenaceae)

Leptolaena Thouars is one of the first described genera within Sarcolaenaceae, but represents the last great species-level taxonomic challenge in this endemic Malagasy plant family. As currently circumscribed, this genus comprises three subgenera, two of which, Mediusella Cavaco and Xerochlamys (Baker) Cavaco, exhibit patterns of morphological variation that have been understood differently and have led to an unstable taxonomy, such that a consensus on the delimitation of species has yet to be reached. Principal component analysis of morphological characters was performed on 211 herbarium specimens in order to evaluate the morphological variation within the two subgenera and to clarify historically problematical species boundaries. The results showed that ten entities could be distinguished on the basis of vegetative, floral, and fruit characters, and that they provide a robust basis for proposing a new species-level taxonomic framework.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 559–574.     

Origin and relationships of the myco-heterotrophic liverwort Cryptothallus mirabilis Malmb. (Metzgeriales, Marchantiophyta)

Heterotrophic life histories have evolved independently numerous times in the angiosperms. In non-vascular embryophytes, heterotrophy is known only in the genus Cryptothallus . Cryptothallus mirabilis obtains photosynthates indirectly from a host tree via a basidiomycete that is simultaneously ectomycorrhizal on the host, a strategy known as myco-heterotrophism. This simple thalloid liverwort was initially described as an albino variant of Aneura pinguis , and the literature varies on whether it should be considered as such, as a distinct species of Aneura , or as a separate genus. Here, the relationships of C. mirabilis within the family Aneuraceae are reconstructed using DNA sequence data from the chloroplast ( rps 4, rps 14, atp B- rbc L spacer, trn G), mitochondrial ( trn S), and nuclear (26S and ITS) genomes. Several allopatric populations of C. mirabilis and of both sympatric species of Aneura (i.e. A. pinguis and A. maxima ) were included. Cryptothallus mirabilis is resolved as having a single origin from within Aneura , and hence the myco-heterotrophic liverwort should be considered as a distinct species of Aneura , rather than an autonomous genus. The fungal symbiont of the photosynthetic A. pinguis is of the same genus, Tulasnella , as that of C. mirabilis , suggesting that the heterotrophic life strategy might have evolved from a pre-existing symbiosis.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 1–12.     

Comparative biology of pollination systems in the African-Malagasy genus Brownleea (Brownleeinae: Orchidaceae)

The role of pollinators in the evolution of the African-Malagasy orchid genus Brownleea (Brownleeinae) was investigated. Taxa show specialization for pollination by bees ( B. parviflora , B. recurvata ), short-proboscid flies ( B. galpinii ), and long-proboscid flies ( B. macroceras , B. coerulea ). All species in the genus produce nectar, but some ( B. coerulea , B. galpinii ) appear to mimic flowers of abundant sympatric species as an additional strategy to attract pollinators. Species investigated in terms of their breeding systems ( B. coerulea , B. parviflora , B. macroceras , B. galpinii ) are reliant on pollinator visits for seed production. Self-pollination results in strong inbreeding depression during embryo formation. A phylogeny of the genus, constructed using data from the ITS1-5.8S-ITS2 region and morphology, indicates that fly pollination is likely to be basal in the genus, and that there has been a single shift to bee pollination.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 65–78.     

Interspecific variation of acoustic signals in Mediterranean gobies (Perciformes, Gobiidae): comparative analysis and evolutionary outlook

Sound production of 11 Mediterranean goby species, belonging to five different genera, have been comparatively analysed on the basis of the quantitative properties of the acoustic signal emitted by the male in both the reproductive and aggressive context. The results obtained showed that three groups of species can be recognized on the basis of signal similarity: the larger sized species (genus Padogobius and Gobius paganellus ) producing tonal sounds, showing high values of pulse rate and low values of duration; the larger-sized species producing grunt sounds (genus Gobius and Zosterisessor ) with low pulse rate and low duration; and the small-sized species producing grunt sounds (genus Pomatoschistus and Knipowitschia ) with low pulse rate and high duration. The comparison between these results and those found in previous studies suggests congruence between the acoustic affinities among species and that obtained by means of morphological and genetic data. Furthermore, first hypotheses on the evolution of acoustic communication and the associated mechanisms in this fish group are suggested.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 763–778.     

Sperm ultrastructure in the marine bivalve families Carditidae and Crassatellidae and its bearing on unification of the Crassatelloidea with the Carditoidea

An investigation of sperm ultrastructure in representatives of the marine bivalve families Carditidae (Carditoidea) and Crassatellidae (Crassatelloidea) reveals features o f taxonomic significance. Spermatozoa of Cardita muricata (Carditidae) and Eucrassatella cumingii, E. kingicola, Talabrica aurora (Crassatellidae) differ from the classic aquasperm type in having an elongate acrosomal vesicle and elongate nucleus. In addition, the midpiece region in these species is composed of a distinctive, and here considered t o be apomorphic. arrangement of 8 (rarely 7 or 9), tightly abutted mitochondria grouped around ii dense rod which is continuous with the distal centriole (basal body). A recognizable (i.e. triplet-substructure) proximal centriole is therefore absent in mature spermatozoa of crassatellids and carditids. This situation contrasts with the presence of an unmodified proximal centriole in the spermatozoa o f all other investigated bivalves. Observations on crassatellid and carditid spermatids indicate that the dense r o d is derived through metamorphosis of the proximal centriole. The shared and highly characteristic midpiece features of spermatozoa of the Crassatellidae and Carditidae clearly indicate ii close relationship between these families and support the unification of the Crassatelloidea and Carditoidea into a single superfamily Carditoidea Fleming. 1820 (date priority over Crassatelloidea Férussac. 1822).     

Comparative study of sperm ultrastructure of Donax hanleyanus and Donax gemmula (Bivalvia: Donacidae)

The ultrastructure of bivalve spermatozoa can be species‐specific and often provides important taxonomic traits for systematic reviews and phylogenetic reconstructions. Young individuals of the Donacidae species Donax hanleyanus are often identified as samples of Donax gemmula. Hence, the spermatozoa ultrastructure of both species was described in the present work, aiming to identify characters that could be useful for further taxonomic and phylogenetic analyses. D. hanleyanus and D. gemmula spermatozoa were different especially in relation to acrosomal characteristics and chromatin condensation. The spermatozoon produced by D. hanleyanus had a nucleus (exhibiting granular chromatin with a rope‐like appearance) capped by a long and conical acrosomal vesicle, which extended itself outward beyond the anterior nuclear fossa. Otherwise, the nucleus of the sperm cell of D. gemmula showed well‐compacted chromatin, and its acrosome, which was partially inserted into the anterior nuclear fossa, had a bubble‐like tip. In conclusion, the conspicuous ultra‐structural differences found between the spermatozoan morphologies were helpful for the discrimination of the species. In conclusion, our results suggest that analyses of sperm ultrastructure of the bivalves in the family Donacidae can be valuable to investigate their taxonomic relatedness. The present results also contribute to assess the monophyletic status of the family.     

Faecal case architecture in the gibbosus species group of Neochlamisus Karren, 1972 (Coleoptera: Chrysomelidae: Cryptocephalinae: Chlamisini)

Constructions composed of faeces are rare in insects, but occur in certain leaf-beetle clades. Members of the subfamily Cryptocephalinae share a complex behavioural and morphological synapomorphy, involving portable faecal cases that house the immature stages. A maternally initiated egg case is expanded and enlarged through four larval stadia, then sealed to provide a pupal chamber from which adults eventually emerge. We analyse and compare faecal-case architecture in ten taxa of the cryptocephaline genus Neochlamisus , and assess structural variation within a life cycle, between different 'host forms' of Neochlamisus bebbianae , and among species. These cases proved to be comprised primarily of faeces, with plant trichomes representing the only common secondary component. General architectural trends reflected variation in shape, faecal texture, and the incorporation and density of trichomes. Deviations of the Neochlamisus case from a simple geometrical gnomon reflect the changing body size of the animal, differential application of faeces, and shifts in the orientation of the carriage of the case. Neochlamisus cases are presumably energetically costly to produce, carry, and maintain, and some adaptive hypotheses of case evolution are proposed. Additionally, literature on case morphology in other camptosomates is reviewed.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 315–351.     

A palynological study of the genus Mentha L. (Lamiaceae)

The pollen morphology and exine structure of 10 Mentha L . species were investigated using light microscopy and scanning electron microscopy. The pollen grains of all 11 species were hexazonocolpate with granular membranes and a circular amb, varying in shape from prolate-spheroidal to suboblate. Different colpus shapes were recognized in M . ×  dumetorum . The exine was bireticulate in section Pulegium , and reticulate in section Menthae . A correlation was found between pollen size and chromosome number. The results indicate that the pollen characters of the genus Mentha are valuable for taxonomic applications and may be useful for classification.  © 2008 Uludag University. Journal compilation © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 141–154.     

A new dwarf boa (Serpentes, Booidea, 'Tropidophiidae') from the Early Oligocene of Belgium: a case of the isolation of Western European snake faunas

Falseryx neervelpensis sp. nov. (Booid-grade, 'Tropidophiidae') from the earliest Oligocene (MP 21) of Belgium is described on the basis of vertebrae coming from all major portions of the vertebral column. In its peculiar caudal osteology, the snake approaches the unique morphological pattern characteristic of the living Neotropical Tropidophiinae. This is the first time such a complete and informative vertebral column of a dwarf boa has been described. The genus Falseryx was absent from Western Europe in younger parts of the Oligocene, but reappeared at the end of the Early Miocene. This dispersal pattern provides additional evidence that in most phases of the Oligocene and Early Miocene Western European snake faunas were effectively isolated from possible influences from the East.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 393–406.     

Their Day in the Sun: molecular phylogenetics and origin of photosymbiosis in the 'other' group of photosymbiotic marine bivalves (Cardiidae: Fraginae)

The subfamily Fraginae (Cardiidae) is a morphologically diverse group of small-bodied marine clams inhabiting shallow seas worldwide. Like the exclusively photosymbiotic giant clams (Cardiidae: Tridacninae), some fragines are known to host zooxanthellae photosymbionts. However, surveys to widely determine photosymbiotic status and the lack of a comprehensive phylogeny have hindered attempts to track the evolution of photosymbiosis in the group. Worldwide sampling of all fragine genera and subgenera with phylogenetic reconstructions based on four gene regions [nuclear (28S) and mtDNA (16S, cytochrome oxidase I, cytochrome b )] does not support a monophyletic Fraginae. Sampled taxa form four restructured clades: (1) the ' Fragum ' group, (2) the ' Trigoniocardia ' and ' Ctenocardia ' groups, (3) the ' Parvicardium ' group and (4) the ' Papillicardium ' group. Maximum likelihood analyses strongly support a clade of European cardiids uniting species from three subfamilies. Live examination of > 50% of species reveals that less than half of derived genera and subgenera host photosymbionts, supporting a single and relatively late origin of photosymbiosis in the Fraginae. The evolutionary implications for a small and little modified earliest diverging photosymbiotic lineage are discussed.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 448–465.     

A new hydrocharitacean seagrass from the Eocene of Florida

Middle Eocene seagrass compressions occur in the Avon Park Limestone Formation near Gulf Hammock on Florida's west coast. One group of specimens resembles two seagrass species of the hydrocharitaceans, Thalassia and Enhalus , that are living today in tropical and subtropical shallow marine environments. The Eocene plant has a dimorphic rhizome system consisting of a creeping, monopodial, plagiotropic rhizome with small roots and orthotropic laterals (short shoots) that occur in pairs every three to five nodes. Laterals bifurcate and produce glabrous eligulate leaves in an alternate and distichous arrangement. Foliage leaves have fibrous basal sheaths, blades with parallel venation, perpendicular and oblique cross veins, prominent midrib, and smooth, entire margins. Throughout the plant are numerous brown-coloured tanniferous dots and deposits of small calcium oxalate crystals. Based on features of these non-reproductive structures, the Florida Eocene seagrass is recognized as a new genus and species Thalassites parkavonensis in the Hydrocharitaceae.   © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 19–30.     

The evolution of sperm and non-sperm producing organs in male Drosophila

The male ejaculate is made up of two components: sperm and non-sperm. There has been little consideration of how these two basic compartments evolve. If they are subject to trade-offs, theory predicts that when the sperm competition raffle is unfair, when seminal fluid proteins stimulate fecundity and/or when ejaculate components alter fertilization success, there will be differential selection on sperm versus non-sperm ejaculate characteristics. However, the fundamental assumption that there are trade-offs between sperm and non-sperm ejaculate compartments in Drosophila has not yet been tested. To address this, we examined testis (sperm producing) and accessory gland (non-sperm producing) size across 22 species of Drosophila . We also examined how these characters varied with copulation duration, which may represent an additional target for sperm competition. The results showed no evidence of a trade-off between testis length and accessory gland length. Copulation duration correlated negatively with accessory gland length and there was a positive correlation with testis length, but only after correcting for body size. Overall, the results suggest no evidence for gross trade-offs in sperm versus non-sperm compartments across these Drosophila species, and motivate more detailed examination of ejaculate investment patterns.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 505–512.     

Molecular phylogeny of the western Atlantic species of the genus Portunus (Crustacea, Brachyura, Portunidae)

The genus Portunus encompasses a comparatively large number of species distributed worldwide in temperate to tropical waters. Although much has been reported about the biology of selected species, taxonomic identification of several species is problematic on the basis of strictly adult morphology. Relationships among species of the genus are also poorly understood, and systematic review of the group is long overdue. Prior to the present study, there had been no comprehensive attempt to resolve taxonomic questions or determine evolutionary relationships within this genus on the basis of molecular genetics. Phylogenetic relationships among 14 putative species of Portunus from the Gulf of Mexico and other waters of the western Atlantic were examined using 16S sequences of the rRNA gene. The resultant molecularly based phylogeny disagrees in several respects with current morphologically based classification of Portunus from this geographical region. Of the 14 species generally recognized, only 12 appear to be valid. We recommend that P. vossi be hereafter regarded as a junior synonym of P. spinimanus and that P. bahamensis be regarded as a junior synonym of P. depressifrons . Our analysis suggests that western Atlantic members of the genus can be subdivided into at least three well-defined clades. Pending further molecular analyses with a large subset of species, it appears that the genus is not monophyletic and that it warrants further taxonomic revision.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 150 , 211–220.     

A synopsis of Goniothalamus species (Annonaceae) in Thailand, with descriptions of three new species

A comprehensive taxonomic revision of Goniothalamus species (Annonaceae) occurring in Thailand is presented for the first time. Twenty-five species are recognized, including three that are described as new to science ( Goniothalamus aurantiacus from South-Western Thailand, Goniothalamus maewongensis from Northern Thailand, and Goniothalamus rongklanus from Northern and North-Eastern Thailand). Several taxonomic and nomenclatural misunderstandings are corrected. The name G. griffithii is shown to be widely misapplied for populations in Northern Thailand, for which the name G. calvicarpus should be applied; 'true' G. griffithii is restricted to South-Western Thailand and Myanmar. In addition, the widely used name G. marcanii is shown to be a synonym of G. tamirensis , and the name G. latestigma , previously regarded as a synonym of G. undulatus , is reinstated. Goniothalamus cheliensis is furthermore newly recorded from Thailand. Most species are restricted to Peninsular Thailand and represent a Malesian floristic component.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 355–384.     

Killer sperm whale: a new basal physeteroid (Mammalia, Cetacea) from the Late Miocene of Italy

Zygophyseter varolai , a new genus and species of Physeteroidea (Cetacea, Odontoceti), is based on an almost complete skeleton from the Late Miocene (Tortonian) in southern Italy. The extreme elongation of the zygomatic process of the squamosal and the circular supracranial basin (probably for housing the spermaceti organ) delimited by a peculiar anterior projection of the supraorbital process of the right maxilla are the most distinctive features of this bizarre sperm whale. Large body size, large teeth present in both lower and upper jaw, and anteroposteriorly elongated temporal fossa and zygomatic process of the squamosal indicate that this cetacean (for which we suggest the English common name killer sperm whale) was an active predator adapted to feeding on large prey, similarly to the extant killer whale ( Orcinus orca ). A phylogenetic analysis reveals that Zygophyseter belongs to a Middle–Late Miocene clade of basal physeteroids, together with Naganocetus (new genus for the type of ' Scaldicetus ' shigensis ). Moreover, the phylogenetic analysis shows evidence of a wide physeteroid radiation during the Miocene and that the extant Physeter and Kogia belong to two distinct families that form a clade representing the crown-group Physeteroidea.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 148 , 103–131.     

Towards a revision of the genus Parastenocaris Kessler, 1913: establishment of Simplicaris gen. nov. from groundwaters in central Italy and review of the P. brevipes-group (Copepoda, Harpacticoida, Parastenocarididae)

A new genus Simplicaris (Copepoda, Harpacticoida, Parastenocarididae) is established to accommodate two species collected from deep groundwater in Italy, S. lethaea sp. nov. and S. veneris (Cottarelli & Maiolini, 1980) comb. nov. Parastenocaris hippuris Hertzog, 1938 and P. aedes Hertzog, 1938 are ranked as incertae sedis within the genus. Members display complete absence of leg 5 in both sexes and an unusual elongation of the first exopodal segments of legs 1–4, in which exp-1 is distinctly longer than exp-2 or -3, or as long as exp-2 and -3 combined. As the systematic status of the family Parastenocarididae and of the type genus Parastenocaris is still in flux, a list of phylogenetically informative characters is proposed, along with a discussion of their various states in representative members of the family. The genus Parastenocaris sensu stricto is redefined to comprise only the brevipes -group. The remaining members of the genus are considered Parastenocaris sensu lato pending a thorough revision of the family.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 417−436.     

Sarcinomyces sideticae, a new black yeast from historical marble monuments in Side (Antalya, Turkey)

A new species of Sarcinomyces , a melanized fungus with meristematic development, is described. On the basis of small subunit and internal transcribed sequence regions of ribosomal DNA sequencing, the new species was accommodated in the anamorph genus Sarcinomyces (Herpotrichiellaceae, Chaetothyriales) close to S. petricola .  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 373–380.