Wood anatomy of Krameriaceae with comparisons with Zygophyllaceae: phylesis, ecology and systematics

Wood of nine species of Krameria (including all clades proposed within the genus) reveals a few characters related to infrageneric systematics; most relate primarily to ecology and habit. Wood of Krameria closely fits quantitative data reported for desert shrubs. Lack of vessel grouping correlates with the presence of densely pitted tracheids. Wood xeromorphy in Krameria may relate in part to hemiparasitism. Tracheid presence may also account for relatively low vessel density. Wood anatomy of six species of Zygophyllaceae (including both genera of Morkillioideae) is compared with that of Krameriaceae because recent phylogenies propose that these two families comprise the order Zygophyllales. Several wood characters appear to represent synapomorphies reflecting this relationship. Differences in wood anatomy between Krameriaceae and Zygophyllaceae are believed to represent autapomorphies. Notable among these include Paedomorphic Type II rays (Krameriaceae), storying (Zygophyllaceae), presence of vestured pits (Zygophyllaceae), and differentiation into vasicentric tracheids and fibre-tracheids (Zygophyllaceae). The latter feature is referable to the concept of fibre-tracheid dimorphism. Recognition of Krameriaceae as separate from Zygophyllaceae is supported by wood characters. Wood of Zygophyllales does not conflict with the idea that the order belongs to rosids, with Malpighiaceae as the outgroup of Zygophyllales.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 257–270.     

The largest eukaryotic genome of them all?

We report the largest eukaryotic genome to date in the monocot Paris japonica (Melanthiaceae, 1C = 152.23 pg), measured using flow cytometry. This value is 15% larger than any previous estimate and extends the range of genome sizes to c. 2400‐fold across angiosperms and c. 66 000‐fold across eukaryotes. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164 , 10–15.     

A revision of Danielssenia perezi Monard, D. paraperezi Soyer, D. eastwardae Coull (Harpacticoida; Paranannopidae) and their transfer to a new genus

The harpacticoid copepod Danielssenia perezi Monard, 1935 is redescribed on the basis of the only available material from the Scilly Isles off south-west Britain. Sentirenia gen. nov is erected because this species exhibits significant differences from the type species Danielssenia typica Boeck, 1872 in the structure of the antennule; the presence of sensory aesthetascs on, and structure of, the mandible, maxillula and maxilla; the form of the female P5; the setation of the swimming legs and details of the sexual dimorphism on the endopod of the male P2. Further, it is shown that the characters by which D. paraperezi Soyer, 1970 was originally distinguished from D. perezi are no longer valid and D. paraperezi is a junior synonym of S. perezi which now assumes a boreo-mediterranean distribution. A re-examination of the type material of D , eastwardae Coull, 1971 shows that this species is identical to S. perezi in the structure of the mouthparts (including the presence of aesthetascs on the mandible, maxillula and maxilla) and setation of P1–P5. However, within the genus Sentirenia, its specific status is maintained by virtue of a 5-segmented female antennule; a difference in the shape of the endopodal lobe of the female P5; the sexually dimorphic characters of the male P2 endopod; and variation in the ornamentation of some appendages.     

Floral anatomy of Thomandersia (Lamiales), with particular reference to the nature of the retinaculum and extranuptial nectaries

Thomandersia is an isolated genus that is currently unplaced in Lamiales. In the past it has been classified in Acanthaceae or Pedaliaceae, on the basis of intuitive assessments of a limited number of morphological characters. Recent molecular sequenced-based phylogenies have suggested a relationship to Bignoniaceae, Schlegeliaceae or Verbenaceae. Here we present new observations of the floral anatomy of Thomandersia , with particular emphasis on the structure of the retinaculum, a character shared with Acanthaceae, and calyx nectaries, which may be shared with other families in Lamiales. The morphological and anatomical characters of Thomandersia are discussed in the context of recent phylogenetic hypotheses for Lamiales, with the aim of identifying potential primary and secondary homologies between Thomandersia and related families in Lamiales. We find that Thomandersia shares a range of characters with each of the families to which it might be sister-group, and that some of these primary homologies must therefore be homoplastic. In particular, if the topology based on molecular sequence data is correct, the retinacula of Thomandersia and Acanthaceae are homoplastic and represent an example of parallel morphological evolution.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 469–482.     

Dealing with allometry in linear and geometric morphometrics: a taxonomic case study in the Leporinus cylindriformis group (Characiformes: Anostomidae) with description of a new species from Suriname

To achieve maximum efficacy, taxonomic studies that seek to distinguish amongst species must first account for allometric shape variation within species. Two recently developed software packages (SMATR and MorphoJ) offer regression‐based allometric approaches that are notable for their statistical power and ease of use and that may prove highly useful to taxonomists working with linear or geometric morphometric data. We investigate species delimitation of the slender‐bodied fishes in the Leporinus cylindriformis group using these programs and demonstrate the utility of the allometric corrections that they provide. Without allometric correction, many pairs of species are difficult to distinguish on the basis of morphometrics, but once regressions are used to account for marked allometric variation within species, most of the recognized species in this group can be readily distinguished with linear or geometric morphometrics, particularly using variation in the depth of the body. Both approaches returned congruent patterns of separation amongst putative species, but the geometric approach in MorphoJ distinguished amongst four more pairs of species than did the linear approach in SMATR and appears to provide slightly more statistical power. Based on distinctive morphometrics, meristics, and coloration, a highly elongate species of Leporinus from the Suriname, Corantijn, and Coppename rivers of Suriname is described herein as a new species, Leporinus apollo sp. nov. The unique L. cylindriformis holotype from Porto de Moz, Brazil differs in morphology, meristics, and pigmentation from specimens commonly referred to that species from the main basin of the Amazon; the latter specimens may represent an additional undescribed species. The L. cylindriformis holotype itself may represent a rare species or a specimen collected at the edge of its native range. Measurements of the holotype and paratype of Leporinus niceforoi, which were collected in the Amazonian slope of Colombia, differ substantially from similarly pigmented and putatively conspecific specimens from Amazonian portions of Ecuador and Peru. Recently collected specimens from Colombia are needed to determine whether the observed morphometric variation encompassed by the current concept of L. niceforoi indicates a morphocline within a single species, suggests the presence of multiple cryptic species, or results from shrinkage of the types. In all these cases, linear or geometric morphometric data can reliably differentiate amongst species, but only after one accounts for allometric shape variation. The new SMATR and MorphoJ software packages both offer easy and effective approaches to such allometrically informed taxonomy, and may prove useful to any systematist working on taxa that change shape as they grow. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 103–130.