General consensus in linguistics is that language context (or ''co-text'') plays crucial role in describing linguistic properties of language items. Isolated units are, as a corollary to this statement, inherently ambiguous (polysemous and/or polyfunctional). In this paper we describe the most influential forces leading to disambiguation of language units, specifically the role of n-gram length on its ambiguity.
The most influential achievement of corpus linguistics lies in the growing importance of context in the description of language. This is also reflected by context analysis which is introduced in this paper. Context analysis is an umbrella term for a bundle of methods sharing the same hypothesis: that all the features (form, meaning, function) of the language phenomena are mirrored by the context which they enter. It is important to emphasise that by the term ''context'', it is meant here not only one or two adjacent tokens in a particular text, but all the neighbouring units (e.g. words, lemmas, part of speech tags etc.) which co-occur with a given word in all of its instances in a corpus. The paper discusses various types of context (range, type of contextual units etc.) and their effect on the analysis. By comparing contexts of distinct words or word groups we may find out what the similarities and differences are between language units, phenomena or even groups of lexemes. This type of research was conducted here to determine the relations between parts of speech.
The larval morphology of Aphodius (Plagiogonus) nanus Fairmaire, 1860 and A. (P.) arenarius (Olivier, 1789) are described and redescribed, respectively. The common characters of both species, and the specific diagnostic characters are provided and discussed. The most important morphological characters of the larvae of Plagiogonus Mulsant, 1842 are the longitudinal alignment of the anterior setae of the stipes, the spatulate form of the posterior-lateral setae of the glossae of the hypopharynx, the slight development of the anal lobe slit, the form of the epitorma of the epipharynx, the slight sclerotization of the pternotormae and the relative length of second antennal segment. A key to the larvae of both species of Plagiogonus is presented along with life history data and the preferred food of these species. This study shows that A. arenarius and A. nanus feeding habits are closer to saprophagy than to coprophagy.
The third instar larvae of three Anisoplia species, Anisoplia baetica Erichson, 1847, Anisoplia depressa Erichson, 1847 and Anisoplia remota Reitter, 1889 are described and illustrated to show the diagnostic characters of the species. The third instar larva of the monospecific genus Anthoplia, represented by Anthoplia floricola (F., 1787) is also described and illustrated. These four species are included in a revised key to the larvae of Anisopliini, which now includes four genera, and ten species. The taxonomic status of Anthoplia based on the larval morphology, is discussed.
A provisional larval groundplan of the family Hygrobiidae is provided through descriptions of internal and external features of three of six extant species, Hygrobia hermanni (Fabricius, 1775), H. wattsi Hendrich 2001 and H. australasiae (Clark, 1862) and phylogenetic interpretations. Hygrobiidae larvae are morphologically differing dramatically from all other known Adephaga by 20 autapomorphies. Structures involved with feeding, i.e., mouthparts, prepharynx and foregut are highly modified as a result of a specialisation on small tubificid worms and chironomid larvae. A placement of Hygrobiidae within Dytiscoidea is well supported by the reduced condition of the terminal abdominal segments, and the presence of 10 ancestral setae on femur and a clade comprising Hygrobiidae, Amphizoidae, and Dytiscidae by the presence of thin and elongate caudal tentorial arms, a very strong musculus verticopharyngalis and a longitudinally divided adductor tendon of the mandible. A highly modified foregut, reduced terminal spiracles VIII and the presence of tubular gills are features which distinguish hygrobiid larvae from those of other groups of Dytiscoidea (i.e, Amphizoidae, Noteridae, Dytiscidae). A sister-group relationship between Hygrobiidae and Dytiscidae is indicated by a distinctly shortened and transverse prepharynx and a cerebrum and suboesophaeal ganglion shifted to the anterior third of the head. Larvae of the Australian species H. wattsi and H. australasiae share the presence of a bluntly rounded mandible and an apical position of the primary pore MNd in instar I as potential synapomorphies.
Geographic range expansion is one of the best documented macroecological consequences of climate change. A concomitant change in morphology has been demonstrated in some species. The relationship between latitudinal variation in morphology (e.g. Bergmann's rule) and the morphological consequences of microevolutionary pressures at expanding range margins have received little attention in the literature. Here we compare morphology of males of two Palaearctic damselfly (Odonata: Zygoptera) species, Coenagrion puella (Linnaeus, 1758) and Pyrrhosoma nymphula (Sulzer, 1776). C. puella has recently expanded its range from the north of England into Scotland. P. nymphula does not exhibit a range margin in the United Kingdom and has established populations in northern Scotland. We demonstrate evidence for spatially correlated variation in body size across the sampling sites between the two species but a deviation in patterns of dispersal-related morphology. P. nymphula exhibited very weak relationships between dispersal-related morphology (wing loading and thorax : abdomen mass ratio) and latitude. However, the more southerly-distributed C. puella exhibited strong relationships between mass investment in dispersal-related morphology and latitude. These trends appear to indicate compensatory growth patterns in cooler environments like those demonstrated for other species. The limits of this compensation for conditions that are close to the limits of a species' tolerance may contribute to the determination of the range margin. Greater variation in morphology towards the range margin has been observed in previous studies in Odonata. As such, the location of the sampling sites relative to the range margin of each species (closer in C. puella than P. nymphula) is highlighted as a potential contributing factor to the variation observed.
Eumerus purpurariae, described from the Canary Islands (Atlantic), has been reared from the stems (platyclades) of the cactus Opuntia maxima (the first known host) on Nueva Tabarca, a Mediterranean island close to the Iberian coast. The egg, larva and puparium of E. purpurariae, as well as its life cycle on the above host-plant are described. The feeding behaviour of the larva in relation to the cephalopharyngeal skeleton morphology is analysed. Based on the present data, comparative table containing the main morphological characteristics of the injurious Eumerus species of the Palaearctic region is presented.
Structures that assist in spreading secretions produced by the metathoracic glands were examined in Reduviidae and Pachynomidae (Heteroptera). The systematic distribution of a row of long and stout setae on the metacoxa, the metacoxal comb, was reinvestigated in a representative sample in both taxa. Observations on living Dipetalogaster maximus (Reduviidae: Triatominae) corroborated the interpretation of this metacoxal comb as an evaporatory device, which assists in atomizing the gland secretions. In addition to the metacoxal comb, a row of stout setae on the metacetabulum - a metacetabular comb - was found in several Reduviidae, which interacts with the metacoxal comb during rotation of the metacoxa. In addition to those atomizing devices, cuticular modifications surrounding the opening of the metathoracic gland, which presumably form evaporatoria, were discovered in Ectrichodiinae. The meshwork-like structure of this cuticle resembles the cuticular modifications found associated with the opening of the Brindley's gland in Reduviidae, but differs from the mushroom-like evaporatoria around the metathoracic glands in most Cimicomorpha and Pentatomomorpha. Thus, two fundamentally different mechanisms to spread secretions of the metathoracic gland - atomization and evaporation - are present in Reduviidae.
We present a molecular phylogeny incorporating all five species of the Palaearctic geometrid genus Lythria, based on a 2810-bp combined data matrix comprising the full sequence of the mitochondrial gene cytochrome oxidase subunit one (COI) and fragments of the nuclear genes elongation factor 1 alpha (EF-1α) and wingless (wgl). L. venustata, which was recently rediscovered from Kazakhstan, is shown to be sister taxon to all other members of the genus. The remaining species within the genus form two pairs of sister species: L. purpuraria groups together with L. plumularia, and L. cruentaria with L. sanguinaria. The phylogeny is well supported by characters of the male genitalia of all Lythria species. In addition to the molecular phylogeny of the genus Lythria, we illustrate the external appearance of L. venustata for the first time and describe the anatomy of its male genitalia.
Eudiplozoon nipponicum (Goto, 1891) Khotenovsky, 1985 (Monogenea: Diplozoidae), is known to parasitise Cyprinus carpio Linnaeus and species of Carassius. In this study, we conducted a taxonomic re-examination of E. nipponicum using genetic analysis and morphological comparisons from different host species from a single water system. rDNA nucleotide sequences of the internal transcription spacer 2 (ITS-2) region (645 bp) showed interspecific-level genetic differences among diplozoids from species of Carassius and C. carpio (p-distance: 3.1-4.0%) but no difference among those from different species of Carassius (0-0.4%) or between those from C. carpio collected in Asia and Europe (0-1.1%). Large variation was observed among 346 bp cytochrome c oxidase subunit I (COI) sequences (0.3-16.0 %); the topology of the phylogenetic tree showed no relationship to host genera or geographical regions of origin. Morphological observation showed that average clamp size of diplozoids from C. carpio was larger than those from Carassius spp. The number of folds on the hindbody was 10-25 for diplozoids from C. carpio and 12-19 for those from Carassius spp. Thus, our ITS-2 sequence and morphological comparison results indicate that diplozoids from C. carpio and species of Carassius belong to different species. The scientific name E. nipponicum should be applied to the species infected to the type host, Carassius sp. of Nakabo (2013) (Japanese name ginbuna). The diplozoid infecting C. carpio (Eurasian type) should be established as a new species: Eudiplozoon kamegaii sp. n. A neotype of E. nipponicum is designated in this report because the original E. nipponicum specimens are thought to have been lost.