Specific features of eye regeneration in multiocular planarians <Emphasis Type="Italic">Polycelis tenuis</Emphasis>

Regeneration and negative phototaxis were studied in planarians Polycelis tenuis, in which the anterior body end is fringed with many eyes. Comparative data for the same indices are given for binocular planarians Girardia tigrina. Multiple eyes regenerated gradually with a decrease in the rate of regeneration and independently from the rate of restoration of the anterior body end, where they are located. Negative phototaxis was restored independently from the total amount of regenerated eyes. It was unstable in both planarian species.     

Regeneration in two freshwater planarian species exposed to methylmercury compounds

The regeneration rate was studied by the morphometric method in planarians Polycelis tenuis and Dugesia lugubris after different periods of exposure on food substrates with high (0.30–0.50 mg/kg wet weight) and low (0.02–0.07 mg/kg) concentration of methylmercury compounds. The planarian growth and the ratio of regenerating tissue area to the total fragment area after transverse cutting were evaluated. The rate of size increment was lower in animals with high level than with low level of methylmercury than with low level of methylmercury. The highest relative and absolute body area increment after amputation was observed in D. lugubris and P. tenius, respectively. Thus, natural methylmercury compounds were shown to inhibit tissue regeneration in planarians in a dose-dependent manner.     

Monoamine- and peptide-containing elements in the body wall and nervous trunks of nemerteans

Localization and morphological peculiarities of cateholamine-containing (CA-C), serotonin-(5HTIR), neurotensin-(NT-IR) and FMRFamide-immunoreactive (FMRFa-Ir) cells and processes in the body wall and lateral nervous trunks of nemerteans were investigated. The following nemertean species from three orders occurring in the White Sea were studied by fluorescent histochemistry and by immunohistochemistry: Lineus viridis, Lineus ruber and Cerebratulus sp. (Heteronemertini), Cephalothrix linearis (Palaeonemertini), and Amphiporus lactifloreus (Hoplonemertini). The similarity and characteristics of morphological types of monoamine-and peptide-containing elements, their distribution and possible participation in regulation of some functions in different nemertean species and in other invertebrates are discussed. We suggest that 5HT-IR and CA-C bi-and multipolar intra-and subepidermal open-type cells prevailing in the body wall perform a receptive function, while the FMRFa-Ir and NT-IR neurons of the nerve trunks and body wall are responsible for efferent innervation of musculature and connections within the nervous system.     

Experience of plant infestation by the omnivorous arthropod <Emphasis Type="Italic">Nesidiocoris tenuis</Emphasis> affects its subsequent responses to prey-infested plant volatiles

Nesidiocoris tenuis, an omnivorous arthropod, infests plants in either the absence or presence of prey arthropods. We studied whether plant-infestation experience of N. tenuis affected its subsequent prey-finding behavior. We used sesame plants and eggplants as food plants for N. tenuis, and common cutworm (CCW) (Spodoptera litura larvae) as prey. We focused on their olfactory response to CCW-infested sesame plants versus CCW-infested eggplants in a Y-tube olfactometer. When N. tenuis adults experienced the infestation of sesame plants for one day, they preferred volatiles from CCW-infested sesame plants to those from CCW-infested eggplants. By contrast, when N. tenuis experienced the infestation of eggplants for one day, they showed no difference in their preference between the two odor sources. When the duration of the infestation of plants was increased to four days, N. tenuis that had experienced sesame plants showed a reversed response: they preferred CCW-infested eggplant volatiles, while those that had infested eggplants again showed no difference in their preference. Next, we studied the olfactory preference of N. tenuis that had previously infested plants with moth (Ephestia kuehniella) eggs. We found that irrespective of plant species and of duration of experience (either one or four days), N. tenuis adults that had previously experienced one plant species showed a significant preference for volatiles from CCW-infested plants of the same species. The blends of the volatiles emitted from CCW-infested sesame plants and those from CCW-infested eggplants were qualitatively different. Possibility to control the olfactory response of N. tenuis to certain prey-infested plant volatiles by adjusting their feeding history is discussed.     

A new Species of <Emphasis Type="Italic">Ceratozamia</Emphasis> (Zamiaceae) from the Sierra Norte of Puebla,Mexico

Recent collections of Ceratozamia from the Sierra Norte of Puebla, Mexico, point to a new undescribed species, which was previously subsumed under the concept of C. mexicana. Identification of this new species resulted from a review of three associated species: C. mexicana, C. tenuis, and C. delucana. Here we describe Ceratozamia totonacorum and provide information regarding its distribution and natural history. The Ceratozamia species from the Sierra Madre Oriental, Mexico, are circumscribed using morphological characters, including a detailed evaluation of reproductive structures such as the apex, position, color and shape of the ovulate strobilus.     

An omnivorous arthropod, <Emphasis Type="Italic">Nesidiocoris tenuis</Emphasis>, induces gender-specific plant volatiles to which conspecific males and females respond differently

Nesidiocoris tenuis Reuter (Heteroptera: Miridae) is an omnivorous mirid bug that preys on diverse generalist herbivorous arthropods. N. tenuis adults are attracted to volatiles from plants induced by their prey, such as tobacco cutworms (CCW) (Spodoptera litura larvae) and two-spotted spider mites (Tetranychus urticae). N. tenuis adults also induce volatiles when they infest plants. In this study, we focused on olfactory responses of N. tenuis males and females to volatiles from eggplants and sesame plants induced by conspecifics of the same or different gender by using a Y-tube olfactometer. Males were attracted to volatiles from plants of both species induced by either males or females. The male preference was biased to volatiles from plants of both species induced by females, probably because the biased response would facilitate their mate-finding. Females were attracted only to volatiles from plants of both species induced by females. Mating occurs multiple times in this species. Thus, the responses would indirectly affect mating of males and females. Slight but significant qualitative and quantitative differences were detected between the volatiles of plants of both species induced by N. tenuis females and those of the plants induced by conspecific males. N. tenuis might use such differences in their gender-specific responses.     

Genetic diversity and reproductive traits in triploid and tetraploid populations of <Emphasis Type="Italic">Gladiolus tenuis</Emphasis> (Iridaceae)

Most perennial herbaceous plants are able to reproduce vegetatively as well as sexually. Sometimes, such plants may lose the capacity for sexual reproduction. We have studied the case of sterility in triploid populations (2n = 3x = 45) of Gladiolus tenuis M.Bieb. in a considerable part of its area of distribution. Initially, we recorded the presence of a large clone of G. tenuis to the east of the Volga River, as a result of isozyme analysis. We also used AFLP fingerprinting to genotype 55 samples from 10 populations of G. tenuis and one population of the closely related G. imbricutus L. This analysis revealed an extremely low genetic diversity in sterile triploid populations of G. tenuis and a rather high genetic diversity in fertile tetraploid populations (2n = 4x = 60) over most of the area of this species. Genetic distances between fertile and sterile populations of G. tenuis were similar to those between different species of gladioli. It appears that a single sterile genotype has spread vegetatively over 800 km, propagating by daughter corms. The study of the reproductive features of G. tenuis suggests that the cause of sterility may be self-incompatibility between individuals of the clone.     

Centromeric and non-centromeric satellite DNA organisation differs in holocentric <Emphasis Type="Italic">Rhynchospora</Emphasis> species

Satellite DNA repeats (or satDNA) are fast-evolving sequences usually associated with condensed heterochromatin. To test whether the chromosomal organisation of centromeric and non-centromeric satDNA differs in species with holocentric chromosomes, we identified and characterised the major satDNA families in the holocentric Cyperaceae species Rhynchospora ciliata (2n = 10), R. globosa (2n = 50) and R. tenuis (2n = 2x = 4 and 2n = 4x = 8). While conserved centromeric repeats (present in R. ciliata and R. tenuis) revealed linear signals at both chromatids, non-centromeric, species-specific satDNAs formed distinct clusters along the chromosomes. Colocalisation of both repeat types resulted in a ladder-like hybridisation pattern at mitotic chromosomes. In interphase, the centromeric satDNA was dispersed while non-centromeric satDNA clustered and partly colocalised to chromocentres. Despite the banding-like hybridisation patterns of the clustered satDNA, the identification of chromosome pairs was impaired due to the irregular hybridisation patterns of the homologues in R. tenuis and R. ciliata. These differences are probably caused by restricted or impaired meiotic recombination as reported for R. tenuis, or alternatively by complex chromosome rearrangements or unequal condensation of homologous metaphase chromosomes. Thus, holocentricity influences the chromosomal organisation leading to differences in the distribution patterns and condensation dynamics of centromeric and non-centromeric satDNA.     

South African mouse shrews (<Emphasis Type="Italic">Myosorex</Emphasis>) feel the heat: using species distribution models (SDMs) and IUCN Red List criteria to flag extinction risks due to climate change

Five species of mouse or forest shrews (Myosorex) are endemic to South Africa, Lesotho and Swaziland, four of which (Myosorex varius, Myosorex cafer, Myosorex longicaudatus and Myosorex cf. tenuis) are associated with montane or temperate grassland, fynbos and/or forest habitats while a fifth (Myosorex sclateri) is associated with lowland subtropical forests. Due to their small size, specialised habitat, low dispersal capacity, high metabolism and sensitivity to temperature extremes, we predicted that, particularly for montane species, future climate change should have a negative impact on area of occupancy (AOO) and ultimately extinction risks. Species distribution models (SDMs) indicated general declines in AOO of three species by 2050 under the A1b and A2 climate change scenarios (M. cafer, M. varius, M. longicaudatus) while two species (M. sclateri and M. cf. tenuis) remained unchanged (assuming no dispersal) or increased their AOO (assuming dispersal). While temperate species such as M. varius appear to be limited by temperature maxima (preferring cooler temperatures), the subtropical species M. sclateri appears to be limited by temperature minima (preferring warmer temperatures). Evidence for declines in AOO informed the uplisting (to a higher category of threat) of the Red List status of four Myosorex species to either vulnerable or endangered as part of a separate regional International Union for Conservation of Nature (IUCN) Red List assessment.     

Anatomy of fishes of genus <Emphasis Type="Italic">Lampanyctus</Emphasis> (sensu lato), its taxonomic structure,and status in the Lampanyctini (Myctophidae) tribe system

An analysis of the structure of lateral musculature of the head and the basic skeletal elements was made in 14 species of genus Lampanyctus, which belong to all of its species groups. Although there are visible differences in the external morphology that are inherent in Lampanyctus from different species groups, stable anatomical differences were not revealed. Apparently, an important role in the evolution of Lampanyctus species was played by the process of paedomorphosis, which is expressed in a weak skeleton ossification, abnormal development or loss of its separate elements, a decrease in the maximum size of the body, and strong watering of body musculature. The absence of osteological differences between the species groups of Lampanyctus indirectly shows the unity of their origin and, therefore, confirms the hypothesis on the monophyly of this genus.     

Developmental dynamics of myogenesis in the shipworm <Emphasis Type="Italic">Lyrodus pedicellatus</Emphasis> (Mollusca: Bivalvia)

Background

The shipworm Lyrodus pedicellatus is a wood-boring bivalve with an unusual vermiform body. Although its larvae are brooded, they retain the general appearance of a typical bivalve veliger-type larva. Here, we describe myogenesis of L. pedicellatus revealed by filamentous actin labelling and discuss the data in a comparative framework in order to test for homologous structures that might be part of the bivalve (larval) muscular ground pattern.

Results

Five major muscle systems were identified: a velum retractor, foot retractor, larval retractor, a distinct mantle musculature and an adductor system. For a short period of larval life, an additional ventral larval retractor is present. Early in development, a velum muscle ring and an oral velum musculature emerge. In late stages the lateral and dorsal mantle musculature, paired finger-shaped muscles, an accessory adductor and a pedal plexus are formed. Similar to other bivalve larvae, L. pedicellatus exhibits three velum retractor muscles, but in contrast to other species, one of them disappears in early stages of L. pedicellatus. The remaining two velum retractors are considerably remodelled during late larval development and are most likely incorporated into the elaborate mantle musculature of the adult.

Conclusions

To our knowledge, this is the first account of any larval retractor system that might contribute to the adult bodyplan of a (conchiferan) mollusk. A comparative analysis shows that a pedal plexus, adductors, a larval velum ring, velum retractors and a ventral larval retractor are commonly found among bivalve larvae, and thus most likely belong to the ground pattern of the bivalve larval musculature.

     

Some chromosome numbers of the CzechoslovakLeguminosae

Chromosome numbers of the Czechoslovak species of the genusLotus, from various localities have been determined. The paper includes the speciesLotus uliginosus Schkuhr,L.tenuis Waldst. etKit. andL. borbásii Ujhelyi.     

Morphological Traits of Two Seed-Feeding Beetle Species and the Relationship to Resource Traits

Morphological traits are useful to investigate insect sex-related differences in body size and to reveal differences in resource use. It has been suggested that as the resource increases, so does the body size of organisms interacting with the resource, highlighting the crucial role of resource quality and quantity in determining the morphological traits of organisms interacting with the resource. Here, we describe morphological traits of two species of Bruchinae, Merobruchus terani (Kingsolver 1980) and Stator maculatopygus (Pic 1930), consuming seeds of Senegalia tenuifolia (Fabaceae: Mimosoideae). We evaluated the influence of monthly sample and sampling sites on tibia and femur length and biomass. In addition, we tested two predictions in which body size related to resource amount and body size related to longevity. Males of M. terani were heavier than females, whereas the two sexes of S. maculatopygus did not differ in biomass. Both species had larger body sizes in the late ripe-fruit stage. With respect to sampling sites, biomass of M. terani did not differ, whereas S. maculatopygus did differ in biomass. Merobruchus terani showed a positive relationship with seed traits, whereas S. maculatopygus showed no relationship. At the same time, fruit traits showed a negative effect on morphological traits for both beetle species. The longevity experiment, performed using only M. terani, showed an equal longevity and seed consumption rate for both sexes. Our study indicates that different species, interacting in the same system and performing similar functional behaviors, respond differently to the same resource.     

Morphological variability,chromosome polymorphism,and problems of identifying individual species of gobies of the group <Emphasis Type="Italic">Ponticola</Emphasis> (Gobiidae) and assessing taxonomic relations of local populations

In connection with the problems of identification of certain species of the genus Ponticola, and especially their juveniles, morphological and genetic studies of gobies collected in the northwestern part of the Black Sea basin were carried out using literature data and museum collections. Karyological data indicate a distinct species status of western (P. odessicus) and eastern (P. eurycephalus) mushroom gobies; the range of the latter includes not only the Sea of Azov but also waters of the Black Sea coast of the Crimean Peninsula; these conclusions are supported by preliminary molecular genetic studies. Based on the obtained results of intraspecific morphological variability of species, we propose morphological characteristics for identification of adult P. syrman and P. odessicus, as well as a specific set of characteristics to identify juvenile (body length less than 50 mm) P. syrman, P. kessleri, and P. odessicus. We reveal differences in the karyotype structure of P. syrman from populations of the Sasyk Lake and the Don River, which do not differ in terms of external morphological characteristics and variability of cytochrome b haplotypes. The need for further research of phylogeography and morphological and karyological variability of P. syrman sensu lato is assumed.     

Musculature of the Ovipositor of <Emphasis Type="Italic">Timia erythrocephala</Emphasis> Wiedemann, 1824 (Diptera,Ulidiidae)

The structure of the ovipositor sclerites and musculature was investigated in Timia erythrocephala Wiedemann, 1824 (Ulidiidae), whose larvae are saprophagous. The ovipositor musculature of this species is compared with that of the previously investigated Tephritidae. Based on morphological analysis, characters common to Ulidiidae and primitive Tephritidae and supposedly plesiomorphic for Tephritidae are revealed. Abdominal segment VII in Timia is compact and consists of tergite and stemite VII fused into a syntergostemite with a visible suture. The preserved suture between the stemite and tergite of segment VII should be regarded as an intermediate state in the process of syntergostemite formation in tephritoid flies, which was completed already in Lenitovena.     

Allelopathic Potential of <Emphasis Type="Italic">Koelreuteria bipinnata</Emphasis> var. <Emphasis Type="Italic">integrifoliola</Emphasis> on Germination of Three Turf Grasses

Allelopathy is very important for the scientific disposition of garden plants. To understand the allelopathic potential of Koelreuteria bipinnata Franch. var. integrifoliola, the germination of Agrostis tenuis Sibth., Festuca arundinacea Schreb. and Lolium perenne L. were determined under laboratory conditions. The results showed that root, stem and leaf aqueous extracts of K. bipinnata var. integrifoliola had allelopathic effects on all three turf grasses, and the allelopathic activity varied according to extract concentrations, test species, and extract sources. Lower extract concentrations did not affect or promoted the germination and initial seedling growth of turf grasses, but the highest concentrations almost had inhibitory effect. The order of allelopathic potentials of the three organs on germination of these receptors was root < stem < leaf. And at the highest concentration of leaf extract, the most strongly inhibition was found in A. tenuis, followed by F. arundinaces and then L. perenne. In addition, according to gas chromatography–mass spectrometry (GC–MS) analysis, the allelopathic potential compounds and their abundance in root, stem and leaf were obviously different. Therefore, the allelopathic compounds may responsible for allelopathy of K. bipinnata var. integrifoliola. These findings suggested that more attention should be paid to the leaf of K. bipinnata var. integrifoliola for the relative higher allelopathic effects.     

Foraminifera and their associations of a possibly Rhaetian section of the Nayband Formation in central Iran,northeast of Esfahan

The following paper describes the foraminiferal fauna and associated faunal assemblages of the bedded and reef carbonates of the Upper Triassic (most probably Rhaetian) Nayband Formation, which are exposed in a section south of the small town of Bagher-Abad, northeast of Esfahan. Foraminifers are extremely rare in sponge- or coral-dominated bioconstructions and in the bedded carbonates of the Nayband Formation in central Iran. Some carbonate beds are composed of bioclastic wackstone/packstone. These are exposed in the solenoporacean horizon at the uppermost part of the section. Here, the aulotortid- and trocholinid-type foraminifers are relatively abundant. The following foraminiferal taxa with different abundances were found within the carbonates of the investigated section: Trocholina umbo Frentzen, T. turris Frentzen, T. gracilis Blau, Aulotortus tumidus (Kristan-Tollmann), Aulotortus tenuis (Kristan), Aulotortus friedli (Kristan-Tollmann), Coronipora etrusca (Pirini), Semiinvoluta clari Kristan, Turrispirillina? licia variabilis Blau, Galeanella? laticarinata Al-Shaibani, Carter and Zaninetti, Ophthalmidium sp., Agathammina sp., “Sigmoilina” schaeferae Zaninetti, Planiinvoluta carinata Leischner, Planiinvoluta sp., Nubecularia sp., Endothyra sp., Paeolituonella sp. and some sessile agglutinated and nodosariid types. All mentioned taxa are very rare, except the involutinid and trocholinid types. The following species are described as new: Trocholina blaui nov. sp., Spirilina? iranica nov. sp., and Coronipora serraforma nov. sp. Trocholina blaui is usually attached to solenoporacean thalli. Four foraminiferal associations, which are named after the occurrence of the abundant species, were distinguished as Aulotortus tumidus association, Aulotortus friedli association, Trocholina umbo association, and Trocholina blaui association. Aulotortid types and Trocholina umbo were found within the bioclastic wackstone/packstone carbonates. Trocholina blaui is abundant in solenoporacean framestones. The foraminiferal association of investigated carbonates contains a mixed fauna, known from Upper Triassic–Liassic in the Tethyan realm. Carbonates of the whole investigated section are dated—due to occurrence of the genus Aulotortus, with species A. tumidus (Kristan-Tollmann), A. tenuis (Kristan), and A. friedli (Kristan-Tollmann)—as Upper Triassic (most probably Rhaetian). The “typical” foraminifers occurring in the reef biotopes in the northwestern Tethys are either missing or extremely rare in the Iranian bioconstructions.     

The first occurrence of a lingulid brachiopod from the Cretaceous of Sergipe,Brazil, with a restudy of ‘<Emphasis Type="Italic">Lingula</Emphasis>’ <Emphasis Type="Italic">bagualensis</Emphasis> Wilckens, 1905 from southern Patagonia

The lingulid brachiopod Lingularia? notialis sp. nov. is described from the upper Turonian (Cretaceous) of the Sergipe Basin in northeastern Brazil. The rare but well-preserved new material shows morphological characters such as muscle scars, mantle canals and a baculate shell structure. In a preliminary note L.? notialis was referred to Lingularia? bagualensis (Wilckens, 1905) from the uppermost Cretaceous of southern Patagonia, a species restudied here and referred conditionally to Credolingula Smirnova in Smirnova and Ushatinskaya, 2001.     

A multivariate morphometric delimitation of species boundaries in the South American genus <Emphasis Type="Italic">Nicoraepoa</Emphasis> (Poaceae: Pooideae: Poeae)

A multivariate morphometric study of the genus Nicoraepoa was carried out to examine patterns of morphological variation among the species and to identify additional characters to allow a clearer delimitation among species. Nicoraepoa is a taxonomically complex genus comprising seven species endemic to South America. Although most of the species are well delimited, two of them, N. andina and N. chonotica, are morphologically similar and very difficult to separate. The morphological variation among species, with overlapping morphological characters, pseudovivipary and possible hybridization make species boundaries unclear. In the present paper, sixty-seven characters were scored for a total of 216 specimens and analyzed using ordination, cluster and discriminant analyses. Based on multivariate results, we recognized species groups and morphological diagnostic characters that allow clearer species delimitation. As a result, N. chonotica has been transferred to N. andina as a subspecies that inhabit southern Patagonia. Other taxa could be recognized and delimited by diagnostic characters: N. erinacea, N. pugionifolia, N. stepparia, N. subenervis subsp. spegazziniana and N. subenervis subsp. subenervis. Moreover, we discuss the possibility that a new species from Bolivia, based on only one specimen, closely related to N. subenervis should be ascribed in Nicoraepoa.