Sequence-based identification of species belonging to the genus Debaryomyces

In the present study we assessed the identification by sequence analysis of the 15 species belonging to the genus Debaryomyces. We found that the following species can be identified both quickly and correctly by direct sequence comparison of the ribosomal 5.8S-ITS region: D. carsonii, D. etchelsii, D. maramus, D. melissophilus, D. occidentalis and D. yamadae. In contrast, the species D. castellii, D. coudertii, D. hansenii, D. nepalensis, D. polymorphus, D. pseudopolymorphus, D. robertsiae, D. udenii and D. vanrijiae showed high sequence similarity in ribosomal regions with one or several species. In these cases, sequence comparison of the ACT1 gene is proposed to ensure unequivocal strain designation.     

Molecular identification of species of the genus Euglossa Latreille (Hymenoptera: Apidae, Euglossini)

Euglossine bees interact with more than 60 plant families of the Neotropical region. The richness and abundance of these bees have been intensively studied in different ecosystems using the methodology of capturing males with chemical baits. Females are poorly known for most of the species and morphological characters for their taxonomic classification have not yet been described. The purpose of this study was to use allozymes and restriction patterns of the mitochondrial regions 16S and Cyt b to identify species of Euglossa Latreille. Bees were collected while visiting Thevetia peruviana (Apocynaceae) flowers in five cities of the state of S?o Paulo, Brazil. Three Euglossa species were identified among the 305 individuals collected. Euglossa cordata (L.) was the only species found in all cities, while E. securigera Dressler and E. townsendi Cockerell were restricted to two and one cities respectively. EST-3 was a diagnostic marker, whereas ICD, MDH, ME and PGM were informative for species identification when used in combination. Restriction by VspI of the amplified 16S fragment differentiated the three species and showed intraspecific polymorphism for E. cordata and E. securigera. The Cyt b region showed distinctive patterns for E. townsendi but it was not possible to differentiate the other two species. Our results describe potentially useful genetic markers for the identification of Euglossa spp. at the species and group level.     

Agglutinated loricae of some Baltic and Antarctic Tintinnina species (Ciliophora)

The abundance and species composition of diatoms adhering tothe loricae of four agglutinated Tintinnina species, Laackmanniellanaviculaefera, Codonellopsis gaussi, Cd.balechi and Tintinnopsislobiancoi, were determined. Diatoms from the Fragdariopsis group,F.cylindrus and F.pseudonana, dominated on tintinnid loricaefrom the Antarctic waters, whilst Thalassiosira spp. were predominanton loricae from the Baltic Sea. Although tintinnids utilizeddiatoms in the environment, it is not a rule that they use onlythese which are dominant. Our results suggest that certain diatomsare actively selected and agglutinated by particular tintinnidspecies.     

Fecundity in relation to wing-morph of three closely related species of the melanocephalus group of the genus Calathus (Coleoptera: Carabidae)

Summary In two successive years the fecundity of the carabid beetles Calathus (Neocalathus) cinctus, C. (N.) melanocephalus and C. (N.) mollis was studied in relation to wing-morph and temperature. Differences were found between the three species in both egg production and timing and length of the oviposition period. In all species the fecundity of laboratory bred beetles was significantly higher than that of females collected in the field. Long-winged females of both cinctus and melanocephalus had significantly higher egg production than short-winged females, and they also tended to produce eggs over a longer period. In mollis only the fecundity of the long-winged morph was established. The observed lower relative fitness of the short-winged morph in both cinctus and melanocephalus contradicts the supposed increase of the frequency of this morph in ageing, more or less isolated, populations of these species. The loss of long-winged genotypes, resulting from flight activities, is considered the most plausible cause of the increase of short-winged beetles in ageing populations. The higher fecundity of macropterous females makes them especially suited for (re)establishing populations.Communication No. 429 of the Biological Station WijsterPresent address and address for offprint requests: Kortenburg 31, NL-6871 ND Rentum     

Myxosporea (Protozoa: Myxozoa) of freshwater fishes in Africa: keys to genera and species

In Africa, about a hundred species of Myxosporea are known to infest fishes in various countries. Species of nine genera have been described in freshwater fishes: Myxidium, Sphaerospora, Myxobilatus, Myxobolus, Thelohanellus, Unicauda, Henneguya, Chloromyxum and Kudoa. In the present note, we propose a key to the species infecting freshwater fishes. A systematic revision of some species is given. A list of different species, their hosts and their geographical distribution are also presented.     

Behavioural plasticity in relation to egg and time limitation: the case of two fly species in the genus Anastrepha (Diptera: Tephritidae)

Reproductive opportunities in insects that deposit their eggs in discrete resource patches are frequently limited because the availability of oviposition substrates is often spatially and temporally restricted. Such environmental variability leads individuals to confront time‐ or egg‐limitation constraints. Additionally, species with different oviposition strategies (i.e. single egg layers vs clutch layers) commonly deal with different structural and ecological characteristics of larval host plants. To test the hypothesis that oviposition strategies such as laying eggs singly or in batches (clutches) are related to these constraints (i.e. egg vs time limitation), we compared the lifetime oviposition patterns of two closely related sympatric species of Anastrepha (Diptera: Tephritidae) with different oviposition strategies. We exposed five cohorts of A. obliqua and A. ludens females, over the course of their adult lifetimes, to three conditions of “habitat quality” (measured as host density per cage): unpredictable habitat quality (host density varied randomly from day to day between 1, 5, 15, 30 and 60 hosts/cage), low habitat quality (fixed density of one host/cage) and high habitat quality (fixed density of 60 hosts/cage).
Responses to host density conditions were strikingly different in the two species. (1) Frequency of host visits and oviposition events increased in A. obliqua but not in A. ludens when host densities increased. (2) Anastrepha ludens females accepted low quality hosts (i.e. fruits on which eggs had already been laid and were therefore partially covered with host marking pheromone) significantly more often than A. obliqua females did. (3) Females of A. obliqua adjusted their oviposition activity to variations in host density, whereas A. ludens females exhibited a constant oviposition pattern (i.e. did not respond to variations in host density). Based on the above, it is likely that in A. obliqua oviposition is governed by egg‐limitation and in A. ludens by time‐limitation constraints. We discuss the relationship between the oviposition strategies of each fly species and the fruiting phenology and density of their native host plants. We also address the possible influence of oogenesis modality and parasitism by braconid wasps in shaping oviposition behaviour in these insects.     

Myxosporida (Protozoa): The determination and maintenance of spore size and shape

Data are presented which suggest that the size of fish myxosporidan spores is primarily determined by the parasite's development in the tissues or organ's cavities and the spore's shape is determined by the presence of physiologically and behaviorally suitable fish.     

A new family, genus, and seven new species of Entodiniomorphida (Protozoa) from the gut of African rhinoceros

This report deals with a group of ciliated protozoa with short ciliary bands found mainly in the cecum of black rhinoceros, Diceros bicornis (linnaeus, 1758), and white rhinoceros, Ceratotherium simum (Burchell, 1817) from southern Africa. A new genus, Rhinozeta, based on the sum total of the characteristics of seven new related species is described. The species described are R. rhinozeta n. sp., R. triciliata n. sp., R. caecalis n. sp., R. addoensis n. sp., R. cristata n. sp., R. multiplatus n. sp., and R. unilaminatus n. sp. The specific features of the new genus make it incompatible with any of the known families of the Order Entodiniomorphida containing the ciliates present in the digestive tract of herbivorous mammals. This merits the creation of a new family, the Rhinozetidae.     

The taxonomy of Sarcocystis (Protozoa, Apicomplexa) species

The taxonomy of the heteroxenous apicomplexan protozoan genus Sarcocystis was reviewed, and a list of 122 species with their synonyms and hosts given. Both definitive and intermediate hosts are known for only 56 species. The fine structure of the sarcocyst wall may change with age and is not considered necessarily satisfactory for separating species. Specificity for the intermediate host is not narrow for all species. Earlier work on transmission of the parasite from one intermediate host to another should be repeated in the light of present knowledge of the life cycle of species of Sarcocystis.     

Design of molecular markers for identification of species of the genus Chironomus (Diptera,Chironomidae)

Accurate identification and differentiation of species of the genus Chironomus based on their morphological features is a difficult problem. Unambiguous species identification by means of molecular markers is possible at any stage of the life cycle. Polymerase chain reaction (PCR) with species-specific primers was used to develop molecular markers (amplicons) for identification of Chironomus piger, Ch. dorsalis, and Ch. pseudothummi. Nucleotide sequences of the internal transcribed spacer region (ITS) of the locus coding for ribosomal RNA were used to design species-specific primers for these target species. Each of the species-specific primer pairs yielded species-specific amplicons (molecular markers) only with the DNA of target species: Ch. piger, Ch. dorsalis, and Ch. pseudothummi. Test PCRs with the DNA of eighteen Chironomus species confirmed the specificity of the primers obtained. The molecular markers produced in PCR with the designed species-specific primers permit reliable identification of Ch. piger, Ch. dorsalis, and Ch. pseudothummi and their differentiation from other species of the genus Chironomus.     

寄螨属1新种和革索螨属1新种(蜱螨亚纲:中气门目:寄螨科)

记述寄螨属1新种:简单寄螨Parasitus simplendogynii sp.nov.和革索螨属1新种:泾源革索螨Gamasodes jingyuanensis sp.nov.     

Korean species of the genus Bisnius Stephens (Coleoptera: Staphylinidae)

Two Korean species of the genus Bisnius Stephens are studied. Bisnius macies (Sharp), found along the seashore of some islands, is introduced for the first time in Korea.     

Larval identification of species and subspecies of the genus Hyalomma (Acari: Ixodidae) from Russia and neighbouring territories

The following species and subspecies of Hyalomma Koch, 1844 are recorded from Russia and neighbouring territories, including those involved in natural foci of tick-borne diseases: H. (Hyalomma) aegyptium (Linnaeus, 1758), H. (Euhyalomma) dromedarii Koch, 1844, H. (Euh.) asiaticum asiaticum Schulze et Schlottke, 1930, H. (Euh.) asiaticum caucasicum Pomerantzev, 1940, H. (Euh.) asiaticum kozlovi Olenev, 1931, H. (Euh.) anatolicum Koch, 1844, H. (Euh.) excavatum Koch, 1844, H. scupense Schulze, 1918, H. (Euh.) marginatum marginatum Koch, 1844, H. (Euh.) marginatum turanicum Pomerantzev, 1946, and H. (Euh.) marginatum rufipes Koch, 1844. The geographic distribution and host-parasite relationships of each taxon are discussed. Species characters of the larval stage, that can be distinguished using light microscopy, are found to be very few. These characters include shape of scutum, shape and rate of hypostome denticulation, shape and rate of the development of spurs on coxae I to III. Measurements of some morphological structure and their rations show statistically significant differences between some closely related species, even if qualitative discriminating characters are unknown. Only measurements and their ratios can be used for the discrimination of larval H. anatolicum from larval H. excavatum, because qualitative discriminating features have not been found for these species. The complex structure of the subspecific morhological differentiation of all parasitic stages in the polymorphic species H. asiaticum and H. marginatum is revealed. This structure probably reflects some peculiarities of the microevolutionary processes. Identification key for the larval stage of seven Hyalomma species is provided.