How much information do language users need to differentiate potentially absolute synonyms into near-synonyms? How consistent must the information be? We present two simple experiments designed to investigate this. After exposure to two novel verbs, participants generalized them to positive or negative contexts. In Experiment 1, there was a tendency across conditions for the verbs to become differentiated by context, even following inconsistent, random, or neutral information about context during exposure. While a subset of participants matched input probabilities, a high proportion did not. As a consequence, the overall pattern was of growth in differentiation that did not closely track input distributions. Rather, there were two main patterns: When each verb had been presented consistently in a positive or negative context, participants overwhelmingly specialized both verbs in their output. When this was not the case, the verbs tended to become partially differentiated, with one becoming specialized and the other remaining less specialized. Experiment 2 replicated and expanded on Experiment 1 with the addition of a pragmatic judgment task and neutral contexts at test. Its results were consistent with Experiment 1 in supporting the conclusion that quality of input may be more important than quantity in the differentiation of synonyms.

The present study reviews Perinereis Group 2 species from the Eastern and South-eastern Asian seas based on morphological analysis of the types, non-types and original descriptions, and the use of molecular evidence (COI and 16S rDNA) from newly collected material. These species are characterized by having two bar-shaped paragnaths on pharyngeal area VI, which are often deemed conical when small and pointed, triggering misidentifications as to Neanthes species. New terminology and definition for this particular type of bars are proposed, and the generic position of some resembling Neanthes species is also re-assessed. Five species are transferred to Perinereis: Perinereis babuzai comb. nov., P. belawanensis comb. nov., P. kinmenensis comb. nov., P. shigungensis comb. nov. and P. vitabunda comb. nov. ‘Perinereis aibuhitensis’ species group is newly proposed by encompassing species having proximal dorsal ligule similar throughout the body, dorsal cirri short, and blades of heterogomph falcigers straight with long terminal tooth forming a distinct tendon. Perinereis belawanensis comb. nov., P. linea and P. vitabunda comb. nov. are redescribed. Perinereis linea is regarded as a senior synonym of Nereis (Neanthes) orientalis and Perinereis vancaurica tetradentata based on type material, whereas its exotic status in the Mediterranean Sea is questioned. An identification key to all currently valid species within Perinereis Group 2 is also provided.

During several nematological surveys in cultivated and natural habitats in Khuzestan and Zanjan provinces of Iran, a new species, Bitylenchus parvulus n. sp., two new records for Iran – namely, Tylenchorhynchus agri and Tylenchorhynchus graciliformis – and a population of Bitylenchus parvus and one of Sauertylenchus maximus were recovered and characterized based upon morphological and molecular approaches. The new species is characterized by lip region with five to seven annuli, stylet 17.7 (17.0–18.5) μm long, sub-cylindrical tail narrowing abruptly near terminus giving a bluntly digitate shape to the tail tip, cuticle near anterior part of vulva wrinkled and post-rectal sac occupies whole of tail cavity. The phylogenetic analyses were carried out using molecular data from D2–D3 expansion segments of large ribosomal subunit (28S rRNA) for all studied species and the partial small ribosomal subunit (18S rRNA) for the new species. The representatives of Bitylenchus and Sauertylenchus formed distinct clades from Tylenchorhynchus members, supporting the hypothesis in which Bitylenchus and Sauertylenchus could be considered as valid genera, but rejecting the ‘large-genus’ concept for Tylenchorhynchus. Also, Sauertylenchus ibericus was proposed as a junior synonym of S. maximus based on the results from morphological and phylogenetic analysis. Furthermore, an identification key for all known species included in the three genera Bitylenchus, Tylenchorhynchus and Sauertylenchus is presented herein. The number of transverse annuli on the lip region and presence/absence of post-rectal sac were considered as the main diagnostic characters for classifying the species into seven groups, and other morphological and morphometric characters were subsequently used for distinguishing species in each group.

Typical accounts of imagistic content have focused on the apparent analog character or continuous variability of images. In contrast, I consider the distinctive features of digital images, those composed of finite sets of discrete pixels. A rich source of evidence on digital imagistic content is found in the content-preserving algorithms that resize and reproduce digital images on computer screens and printers. I argue that these algorithms reveal a distinctive structural feature: digital images are always compositional (their parts contribute systematically to overall content), but never inverse compositional (atomic parts may be replaced nonsynonymously without changing content). This indicates a sharp contrast with linguistic representations, which may or may not be compositional, and may or may not be inverse compositional. I argue this result sheds new light on the claim that imagistic content is inherently perspectival.

Biting midges (Diptera: Ceratopogonidae) are a large family of flies that commononly appear in Lower Cretaceous to Miocene strata, with over 280 fossil species (4.3 % of the family), belonging to 49 genera (26 extant; 23 extinct). Morphological characters used in the identification of fossil genera and species are identical to those used in studies of extant Ceratopogonidae and, as a result, their potential indicative value is reliable. Two relictual extant genera, Leptoconops and Austroconops, reported from Lower Cretaceous Lebanese amber, are at least 125 million years old. Certain ceratopogonid genera are indicative for the Lower Cretaceous, Upper Cretaceous, Eocene or Miocene. A morphological character indicative for the Upper Cretaceous and Cenozoic is macrotrichia on the wing membrane of adults. Indicator species and genera are reviewed for all amber deposits. Eocene Baltic amber contains the best known fauna of biting midges, with 109 named species. Some genera are indicative of aquatic and semiaquatic habitats (predaceous genera, subfamily Ceratopogoninae), forests with rotting trees (Forcipomyia), sandy sea shore habitats (Leptoconops), a cold boreal climate (Ceratopogon) or warm climates (Nannohelea, Austroconops, Leptoconops, Meunierohelea, Metahelea). Females require a protein-rich meal and are well known for feeding on the blood of vertebrates, but many feed on other things, so this information can help with the interpretation of palaeoenvironments. Washingtonhelea taimyrica Szadziewski, 1996, described from Siberian amber, is transferred to the fossil genus Palaeobrachypogon: P.taimyricus (Szadziewski, 1996), comb. nov. For Serromyia alphea, mistakenly redescribed and illustrated from Eocene Bitterfeld amber (= Baltic amber) by Szadziewski (1993), a new name – Serromyiaerrata Szadziewski, nom. nov. – is proposed.

The lost snout of Richard Harlan’s specimen of Mosasaurus missouriensis has been rediscovered in the vertebrate palaeontology collections of the Muséum national d’Histoire Naturelle (MNHN) in Paris, France. The specimen (MNHN 9587) bears the handwritten description, ‘Amérique du Nord. Par M. Harlan.’, which translated reads, ‘North America. By/From Mr. Harlan’. Accession information indicates the specimen was a gift to the museum prior to 1860 and was likely gifted from Harlan’s estate after his death. We examine the available history of the collection of the specimen present a description of the rediscovered snout, and demonstrate conclusively the conspecificity of M. maximiliani Goldfuss, 1845 and M. missouriensis (Harlan, 1834a) by providing a revised diagnosis of the taxon.

Trichosirocalus horridus sensu lato has been used as a biological control agent of several invasive thistles (Carduus spp., Cirsium spp. and Onopordum spp.) since 1974. It has been recognized as a single species until 2002, when it was split into three species based on morphological characters: T. horridus, Trichosirocalus briesei and Trichosirocalus mortadelo, each purported to have different host plants. Because of this taxonomic change, uncertainty exists as to which species were released in various countries; furthermore, there appears to be some exceptions to the purported host plants of some of these species. To resolve these questions, we conducted an integrative taxonomic study of the T. horridus species complex using molecular genetic and morphological analyses of specimens from three continents. Both mitochondrial cytochrome c oxidase subunit I and nuclear elongation factor 1α markers clearly indicate that there are only two distinct species, T. horridus and T. briesei. Molecular evidence, morphological analysis and host plant associations support the synonymy of T. horridus (Panzer, 1801) and T. mortadelo Alonso-Zarazaga & Sánchez-Ruiz, 2002. We determine that T. horridus has been established in Canada, USA, New Zealand and Australia and that T. briesei is established in Australia. The former species was collected from Carduus, Cirsium and Onopordum spp. in the field, whereas the latter appears to be specific to Onopordum.

In this study, 15 simple sequence repeat (SSR) markers were used for genetic diversity analysis of 45 almond accessions, which included 25 local cultivars from La Palma Island and three other commercial cultivars. A total of 110 amplification fragments were produced, with an average value of 7.9 alleles per locus. Twelve of the SSR markers can be considered as highly informative, with values of expected heterozygosity and power of discrimination above 0.5 and 0.8, respectively. Due to cases of synonymy and homonymy, 37 different genetic profiles were obtained, with the homonymy of the soft-shell varieties known as ‘Mollar’ being the most significant. Cluster analysis identified four groups within the accessions. One of these groups exclusively consisted of the two commercial cultivars ‘Guara’ and ‘Ferraduel’. The other commercial cultivar used in the study, ‘Desmayo Largueta’, was in a cluster with three cultivars from the same locality. The analysis of molecular variance revealed that the within-localities component accounts for most of the total variation, suggesting that La Palma almond cultivars did not originate independently in different parts of the island. The results of the study reveal the genetic singularity of La Palma almond cultivars and the genetic diversity among them.

Selwynia, is regarded as a senior subjective synonym of Aphanodactylus (Crustacea: Brachyura: Pinnotheroidea: Aphanodactylidae). This synonymy does not affect the family name Aphanodactylidae. A diagnosis is provided for Selwynia laevis and this species is re-described.

Females of the new species Exrima walteri sp. nov. were found in sediment trap samples deployed over different sites of the East Pacific Rise (13°N) at 2600 m depth. Four traps were deposited during the HOPE99 cruise (1999) and recovered during the AMISTAD (1999) cruise on the research vessel ‘L'Atalante’. The new species is distinguished from congeners, E. singula Humes, 1987 and E. dolichopus Humes, 1987, by the following derived characters: first somite of the urosome with 3 (one dorsal and two lateral) stout conical extensions; distal endopodal segment on the swimming leg 4 broad. In addition, many specimens of copepodids I and lecithotrophic nauplii, identified as belonging to Dirivultidae gen. sp., were found in the samples of all sediment traps. This is the first record of copepodids I and of a nauplius of dirivultids from the Pacific Ocean. Study of type and additional material collected during different Ifremer cruises at different vent sites (HERO91, EXOMAR, PHARE and MoMARETO) required synonymy of four species of Aphotopontius Humes, 1987, Stygiopontius Humes, 1987 and Rhogobius Humes, 1987. Aphotopontius rapunculus Humes and Segonzac, 1998 is transferred to the genus Rhogobius because it possesses all presumed derived attributes of this genus: last abdominal somite with lobes at sides of anal operculum; second segment of antennal endopod elongate and slender. A new study of the type material suggests that: Aphotopontius temperatus Humes, 1997 is a synonym of A. atlanteus Humes, 1996; Stygiopontius lumiger Humes, 1989 is a synonym of S. sentifer Humes, 1987 while S. bulbisetiger Humes, 1996 is a synonym of S. pectinatus Humes, 1987. Females of the three synonymized species were found to be sub-adult females at copepodid V. Leg 6 on these specimens is one seta located dorsolaterally on the posterior part of the genital somite. This position for leg 6 is unknown for copepodid V of other siphonostomatoids whose leg 6 is located ventrally at copepodid V; the dorsolateral position is presumed derived and shared by the dirivultid genera Aphotopontius Humes, 1987 and Stygiopontius Humes, 1987. A new key to the Dirivultidae genera is presented.

Twenty-six species recently described from Thailand are revised. Eleven taxa are reduced to synonymy with previously described species, including Leptotrema phaeosporum var. vainiona Räsänen. The following new combinations are proposed: Chapsa calathiformis (Vain.) Lumbsch & Papong, C. laemensis (Homchantara & Coppins) Lumbsch & Papong, Melanotrema melanophthalmum (Homchantara & Coppins) Lumbsch & Papong, Ocellularia albocincta (Hale) Divakar & Mangold, O. guianensis (Sipman) Divakar & Mangold, O. khunantensis (Homchantara & Coppins) Lumbsch & Papong, O. percolumellata (Sipman) Divakar & Mangold, O. subcalvescens (Nyl.) Divakar & Mangold and Ocellularia subgranulosa (Homchantara & Coppins) Lumbsch & Papong.

Studies of type specimens and other specimens of Menegazzia subsimilis and M. dissecta have shown that they are referable to the same taxon. Thus, M. dissecta is reduced to synonymy with M. subsimilis, which is characterized by lacerate soralia protruding from lobe apices or vertical lobules (protuberances), small perforations and the presence of the stictic acid complex in the medulla. It has 2-spored asci. The synonymy implies that M. subsimilis has a much wider distribution range than previously known. It is reported here from Oceania (Hawaii, Solomon Islands), Asia (Japan, Papua New Guinea, Russia), Europe (Austria, Germany, Portugal), South America (Ecuador, Peru), the Caribbean (Dominican Republic, Jamaica) and North America (Canada, USA).

A taxonomic revision of Oreorchis is presented. A key to the species and synonymies, descriptions, illustrations and distributions for each taxon are provided. The status of the genera Kitigorchis F. Maek. and Diplolabellum F. Maek. are discussed. The former is redefined as a monotypic genus, with three of the four species included by Maekawa being returned to Oreorchis; the latter is considered congeneric with Oreorchis. Three species, O. angustata, O. aurantiaca and O. nepalensis, are newly described here and O. indica is reduced to varietal status within O. foliosa. Some outstanding problems in the taxonomy of the genus are noted.

The present work deals with the structure of the cephalic part, traces of the digestive system and gills of Ostenocaris cypriformis (Thylacocephala). The structure of the cephalic part has provoked the most substantial controversy since it has been interpreted as being formed by a pair of enormous compound eyes or as a sac structure that we have called the cephalic sac. Particular attention has been devoted to the minute structure of the cephalic sac. Structures that we have previously termed ‘microsclerites’ can be readily observed, but are by no means easy to interpret.

In many specimens, the basal part of the cephalic area contains abundant traces of alimentary residues. The area thus appears to be part of the digestive system. Our observations do not enable us to give a definitive picture of the anatomical organisation of these animals but do lead to substantial corrections of previously proposed interpretations.