Geometric morphometrics, neural networks and diagnosis of sibling Taterillus species (Rodentia, Gerbillinae)

The lack of diagnostic traits in sibling species means that great quantities of biogeographical and ecological data held in museum collections cannot be utilized effectively, leading to underestimates of biodiversity. In this study we applied neural networks (NN) and canonical variates analyses (CVA) to landmark measurements on the skulls of the West African species Taterillus arenarius , T. petteri , T. gracilis and T. pygargus in an attempt to discriminate species previously identified unambiguously from their karyotypes. Among suggested differences, the relationship between inflation of the tympanic bullae and lower population density is discussed. Cross-validated classification rates did not exceed 73%. Two hypotheses are proposed to explain such high phenotypic similarity: morphological plasticity limited by environmental constraints and the possibility that speciation has been too recent to allow significant morphological divergence.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 77 , 319−327.     

Evolution and determinants of host specificity in the genus Lamellodiscus (Monogenea)

The evolution and determinants of host specificity in Lamellodiscus species (Monogenea, Diplectanidae) were investigated. The 20 known Mediterranean species were studied, all parasites of fishes from the family Sparidae (Teleostei). An index of specificity, which takes into account the phylogenetic relationships of their fish host species, was defined. The link between specificity and its potential determinants was investigated in a phylogenetic context using the method of independent contrasts. Host specificity in Lamellodiscus species appeared to be highly constrained by phylogeny, but also linked to host size. Mapping specificity onto the parasite phylogenetic tree suggests that specialist species do not represent an evolutionary dead end, and that specialization is not a derived condition. It is hypothesized that the ability to be generalist or specialist in Lamellodiscus is controlled by intrinsic, phylogenetically-related characteristics, and that specialist species tend to use large hosts, which may be more predictable.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 77, 431−443.     

Comparative analysis of biological and ecological differentiation of Anemone palmata L. (Ranunculaceae) in the western Mediterranean (France and Spain): an assessment of rarity and population persistence

The western Mediterranean geophyte Anemone palmata L. is one of the most endangered angiosperm taxa in France. The biological and ecological characteristics of French populations are contrasted with those of populations from near the centre of the species distribution in east Spain. A Correspondence Analysis discriminates the French and Spanish populations according to substrate and the composition of the plant communities where they grow. The karyological study reveals that east Spanish plants are autotetraploid, whilst the French are all diploid. In addition, morphological differences were registered, Spanish plants generally being more vigorous. French populations consist mostly of senile plants, without or with very low rates of sexual reproduction, whereas the populations from Spain include all age groups with an important percentage of juvenile plants. The main factors which could affect the French populations are habitat destruction and modification of plant communities due to land-abandonment. Conservation measures should be supported by immediate protection of the French localities and habitats to prevent the total decline of this rare species.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 95–114.     

A revised classification of subtribe Helianthinae (Asteraceae: Heliantheae). I. Basal lineages

Results for nuclear ITS sequences were combined with previously obtained data from cpDNA restriction site studies to provide a comprehensive molecular phylogeny for subtribe Helianthinae. Results from the two molecular data sets were mostly congruent for basally diverging branches of the subtribe. Based on the results, combined with morphological observations, the basally diverging branches are placed in six genera, including one newly described. Bahiopsis is resurrected to accommodate species previously placed in Viguiera subgenus Bahiopsis . Calanticaria is newly proposed for the five species of Viguiera ser. Brevifolieae . Heliomeris is retained for the group sometimes included within Viguiera as sect. Heliomeris . Hymenostephium is revived and enlarged to include a number of species of similar habit and involucre, including members of Viguiera sect. Diplostichis , Haploca-lymma and Garcilassa . Although cpDNA results place the morphologically distinctive Sclerocarpus within the clade including species of Hymenostephium , the ITS data were consistent with morphology in suggesting it to be a distinctive lineage.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 65–76.     

Evidence for ecological speciation in the sister species Candidula unifasciata (Poiret, 1801) and C. rugosiuscula (Michaud, 1831) (Helicellinae, Gastropoda)

This paper studies the speciation of two land snail species in south-east France. By using two mitochondrial and one nuclear gene, the species are shown to be sister species within the larger clade of western European Candidula species. The species never occurred syntopically, but a narrow contact zone population was identified. Recent range expansions inferred from phylogeographical methods indicated that the present day distributions are not limited by the colonization capacity of the species. Analysis of environmental variables suggested distribution along an ecotone. The gastropod community is also correlated to this gradient. Morphometric shell analysis showed that the divergence between the sister species is a result of desiccation-resistant shell characters. We therefore conclude that the cause for the ecological speciation is most probably the establishment of the Mediterranean climate ≈ 3.2 mya. A model of ecological speciation with a moving ecotone is put forward.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79, 611–628.     

Revision of Trigonostomum Schmidt, 1852 (Platyhelminthes, Typhloplanoida, Trigonostomidae) with the description of seven new species

A morphological and taxonomic account of the genus Trigonostomum is provided. All known species are discussed and briefly re-described where necessary. Seven new species are described: T. franki from Curaçao, Florida (USA), the East African Coast and New Caledonia, T. nataschae from the French sub-Antarctic island Kerguelen, T. spinigerum from New Caledonia and T. watsoni from the Australian East Coast and New Caledonia. T. tori and T. galapagoensis , both formerly enclosed in T. setigerum , are considered new species, while T. australis also belongs to the same species group. Proxenetes denhartogi is transferred to Trigonostomum . Based on a comparison of old and new material, T. marki is synonymized with T. penicillatum , while T. prytherchi and T. divae are regarded as junior synonyms of T. lilliei ; T. intermedium and T. quadrifolium are considered synonyms of T. coronatum . Three species are considered species inquirendae : T. brunchorsti , T. piriforme and Marinellia lingulifera . Similarities and differences of the 17 valid species are discussed and summarized in an identification key.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 271–296.     

Clarification of the systematic position of Hippophae goniocarpa (Elaeagnaceae)

New information on (1) Hippophae goniocarpa Y.S. Lian et al . ex Swenson et Bartish and (2) H. goniocarpa ssp. litangensis (Lian et X.L. Chen ex Swenson et Bartish) Lian et K. Sun from China is provided and illustrated. Based on morphological characters and distribution, H. litangensis Y.S. Lian et X.L. Chen ex Swenson et Bartish is re-described as a subspecies. H. goniocarpa (including ssp. litangensis ) is a distinct species and should be placed in Section Gyantsensis of Hippophae , although it has been suggested that sspp. litangensis and goniocarpa are the result of hybridization between H. rhamnoides ssp. sinensis and H. neurocarpa ssp. neurocarpa , and H. rhamnoides ssp. yunnanensis and H. neurocarpa ssp. stellatopilosa , respectively. The type subspecies of H. goniocarpa is distributed in Songpan and Hongyuan Counties of Sichuan Province and Qilian County of Qinghai Province, at 3500–3750 m, whereas ssp. litangensis is found only in Jiawa, Litang County, Sichuan Province at c . 3700 m. A key including the four taxa of sect. Gyantsensis is provided.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 425−430.     

A revision of the status of Lepadogaster lepadogaster (Teleostei: Gobiesocidae): sympatric subspecies or a long misunderstood blend of species?

Molecular (partial mitochondrial 12S ribosomal DNA sequences), morphological and meristic analysis of Lepadogaster lepadogaster lepadogaster , L. l. purpurea and L. zebrina were performed to investigate the relationships between these taxa. On the western shore of mainland Portugal, where the two subspecies of L. lepadogaster occur sympatrically, they differ in microhabitat preferences and their breeding seasons are largely out of phase. This information, combined with data on distribution patterns, led to the following conclusions: Lepadogaster l. purpurea is considered to be a valid species, L. purpurea ( Bonnaterre, 1788 ), different from L. l. lepadogaster , now designated L. lepadogaster ( Bonnaterre, 1788 ). L. zebrina was found to be a synonym of L. lepadogaster . The two newly defined species were found to be in sympatry at Madeira and the Canary islands, the Atlantic coast of the Iberian Peninsula, and the Mediterranean at least as far as Genoa (Italy). Diagnostic characters and a list of synonyms are provided.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76 , 327–338.     

Revision of Rogneda Uljanin, 1870 (Rhabditophora, Eukalyptorhynchia, Polycystididae) with the description of seven new species

A morphological and taxonomical account of the taxon Rogneda is given. A new interpretation of the stylet morphology is presented and a new terminology pertaining to these hard parts is proposed. All known species are discussed and additional information is provided when necessary. Seven new species are described. Five of these are from the Mediterranean: R. colpaerti sp. nov. , R. licyae sp. nov. , R. schaereri sp. nov. , R. valckei sp. nov. and R. vangronsveldi sp. nov . R. verveckeni sp. nov . is from the Atlantic coast of Spain (Galicia). The seventh, R. martensi sp. nov. , is from Indonesia and is the first species of Rogneda to be found outside the Northeast Atlantic and the Mediterranean. All new species can be recognized based on the morphology of the stylets in the male system. A discussion on the similarities and differences of the 22 species is provided, resulting in the grouping of the species into seven morphological groups: the capulata -group, the falcata -group, the hibernica -group, the polyrhabdota -group, the steueri -group, the tripalmata -group and the westbladi -group. R. minuta cannot be placed into any of these groups and therefore stands alone within the taxon. An identification key is provided to facilitate further study of the taxon Rogneda .  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 153 , 1–28.     

Parmelina quercina (Parmeliaceae, Lecanorales) includes four phylogenetically supported morphospecies

Morphological and phylogenetic relationships of the worldwide Mediterranean lichen forming fungus, Parmelina quercina , have been studied. Specimens from western Europe, western North America and southern Australia were analysed using molecular data (nuITS rDNA, nuLSU rDNA and mtSSU rDNA) and selected morphological features (upper cortex maculae, scanning electron microscopy examination of the epicortex, ascospores and conidia shape and size, and amphithecial retrorse rhizines). The results conclusively reveal that: (1) there is not one single species but four separate species in the Mediterranean or sub Mediterranean areas of the world. Parmelina quercina and Parmelina carporrhizans (Euroasiatic species), Parmelina coleae sp. nov. (North America) and Parmelina elixia sp. nov. (Australia); (2) largely debated P. carporrhizans is not a synonym of P. quercina but supported as a valid species circumscribed to Macaronesic relict sites; (3) the geographical isolation of the Australian population is correlated with a large genetic distance; (4) morphological characters (ascospores and conidial variability and thallus epicortex) correlate with the phylogenetic hypothesis; (5) the new or revalidated species within Parmelina quercina are not cryptic species but morphologically recognizable taxa.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 455–467.     

Taxonomic revision of the genus Succisella (Dipsacaceae) in the Iberian Peninsula

A revision of the three endemic Iberian species of Succisella G. Beck ( S. carvalhoana , S. microcephala and S. andreae-molinae ), based on herbarium studies, SEM photographs and field observations, is presented utilizing morphological, palynological, karyological, biogeographical and ecological characters. The distribution of the species in the Iberian Peninsula is shown in a grid map. Full synonymy is given for all taxa.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 351–364.     

Sex-biased initial eggs favours sons in the slightly size-dimorphic Scops owl (Otus scops)

There is considerable controversy concerning the origin of Iberian populations of the Mediterranean chameleon, Chamaeleo chamaeleon . Current opinion dictates that Spanish populations result from introductions during the 18^th and 19^th centuries, with subsequent translocations from the original populations to other parts of Spain. The Portugese population in the Algarve is believed to have been introduced from Africa or Spain during the 1920s. However, Holocene remains of chameleons suggest that the Malaga population at least could have a much older origin. Analysis of sequences from the mitochondrial 16S ribosomal RNA gene of samples from the Iberian Peninsula and North Africa revealed a double origin for the Iberian population. The Mediterranean Iberian (Malaga) population is closely related to Mediterranean North African populations, with Atlantic Iberian populations more closely related to populations of the Atlantic coast of North Africa. The overall genetic differentiation and diversity observed was very low, preventing precise dating of the colonization events. However this low level of differentiation is not consistent with Plio-Pleistocene colonization, the assumed timing for a natural colonization event and suggests that chameleons were probably introduced twice by man in the recent past. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 75 , 1–7.     

Systematics of the tribe Podalyrieae (Fabaceae) based on DNA, morphological and chemical data

Phylogenetic relationships among nine genera and 28 species of the southern African tribe Podalyrieae were estimated from sequences of the internal transcribed spacer (ITS) of nuclear ribosomal DNA as well as morphological and chemical data. Morphological and ITS sequence data produced cladograms with similar topologies, both supporting the monophyly of Podalyrieae (excluding Hypocalyptus ). The combined data sets indicate that subtribe Xiphothecinae are monophyletic, but embedded within Podalyriinae. The high degree of congruence between previous taxonomic hypotheses and those based on DNA data provides further evidence for the utility of ITS sequences in studying phylogeny.  © 2002 The Linnean Society of London , Botanical Journal of the Linnean Society , 2002, 139 , 159–170.     

Is the morphological disparity of lemur skulls (Primates) controlled by phylogeny and/or environmental constraints?

The cranial morphology of Lemur catta and of the five species of the genus Eulemur is investigated here by landmark identification and Procrustes superimpositions. This geometrical morphometric method makes it possible to describe pure shape differences independent of size effects, and to quantify differences between specimens. The aim of this study is to determine whether the morphological disparity of lemur skulls is constrained by the environment and/or by the group's phylogenetic history. First, Procrustes residuals are analysed by principal component analysis and the scatter-plots interpreted against the geographical distributions of taxa to determine whether morphology is correlated with geography. Then, a morphological distance tree is computed and compared with various cladograms reported in the literature to test for any correlation between morphology and phylogeny. Morphological disparity is found to be closely correlated with geographical distribution but independent of phylogeny. This confirms that the morphological disparity of lemur skulls is associated with a high degree of homoplasy, probably as a result of ecological constraints.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76 , 577–590.     

Systematics of two deep-water species from the Indo-West Pacific: Struvea gardineri A.Gepp & E.Gepp and Phyllodictyon orientale (A.Gepp & E.Gepp) Kraft & M.J.Wynne (Siphonocladales, Chlorophyta)

Two rare and ill-known subtidal species of stalked, net-forming green algae, Struvea gardineri A.Gepp & E.Gepp and Phyllodictyon orientale (A.Gepp & E.Gepp) Kraft & M.J.Wynne, are re-described on the basis of the examination of type material and recent collections from the Maldives, Seychelles, and Socotra Island in the tropical Indian Ocean. The taxonomic position of both species is re-appraised on the basis of morphological data (cell division, branching pattern, tenacular cells, crystalline cell inclusions, cell shape, and cell dimensions) and molecular phylogenetic evidence (partial large subunit nuclear ribosomal DNA sequences). On the basis of the occurrence of segregative cell division in young plants of S. gardineri , this species is returned to its original genus, Struvea . Cell division in P. orientale takes place exclusively by centripetal wall ingrowths, confirming its placement in the genus Phyllodictyon as currently defined. However, morphological observations and molecular phylogenetic studies indicate that the delineation of genera on the basis of modes of cell division is problematic, and that the genera Struvea and Phyllodictyon , as presently conceived, almost certainly do not represent natural groups.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 115–132.     

Relationships, classification and evolution of Scleranthus (Caryophyllaceae) as inferred from analysis of morphological characters

Study of floral anatomy, micromorphology, palynology and onotogeny has revealed new characters for phylogenetic analysis in the genus Scleranthus . Cladistic analysis of these characters, along with those previously available, suggests that the genus consists of Eurasian/Mediterranean and Australasian sister clades. Gynoecial morphology and development are closely similar in all species, suggesting the genus is monophyletic despite its disjunct northern and southern hemisphere distribution. Variation in pollen:ovule ratios and their implications for the evolution of Scleranthus species are also discussed and it is concluded that a range of breeding strategies intermediate between autogamy and xenogamy exists in the genus. Single-stamened species of Scleranthus are likely to be obligate autogams, despite their comparatively high pollen:ovule ratios in relation to autogamic species of other genera.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 15–29.     

Rapid radiation of the Mediterranean Luciobarbus species (Cyprinidae) after the Messinian salinity crisis of the Mediterranean Sea, inferred from mitochondrial phylogenetic analysis

Phylogenetic relationships of 64 freshwater Barbus s.s. species distributed in basins around the Mediterranean Sea were assessed using cytochrome b sequences. Our results are in concordance with previous morphological and genetic studies, which proposed that these species belong to two major lineages (or subgenera): Barbus and Luciobarbus . We were particularly interested in phylogenetic relationships among species of the Luciobarbus lineage that are primarily found in the southern Mediterranean region from the Iberian Peninsula to the Middle East. In the Luciobarbus lineage, species that were previously attributed to the Capoeta genus were clustered. In this study, we observed short internodes between monophyletic groups having a geographical agreement around the Mediterranean. However, groups from the opposite sides of the Mediterranean Sea (Iberian Peninsula– Capoeta , north-western Africa–Middle East) seem to be phylogenetically close. We therefore infer that rapid radiation of Luciobarbus species in the Late Miocene better fits our data rather than gradual founder events in the southern Mediterranean. We propose that the biogeographical event along an east–west route, responsible for the present distribution of Luciobarbus species, was the 'Lago Mare' phase of the Mediterranean Sea that provided a rapid dispersal route over extensive distances. This provides new insights into the speciation pattern of this group, and may be of general use in the study of freshwater species in these regions.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 80 , 207–222.