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1.
2.
The male drumming signal of Capnopsis schilleri is studied for the first time. It is a monophasic call composed of 4–8 beats with a decreasing frequency. In the present paper, the drumming signals of some Protonemura species are also recorded and described for the first time both in males (Protonemura alcazaba, Protonemura meyeri and Protonemura navacerrada) and females (P. meyeri, P. navacerrada and Protonemura pyrenaica). The male call is very homogeneous in all the studied species and they consist of a repetition of 2–11 sequences of 6–31 beats, with an inter‐beat interval ranging from 0.034 to 0.088 s. The females have monophasic long signals consisting of a repetition of 5 to 109 beats with an inter‐beat interval of 0.061 to 0.159 s. It is extraordinary that females produced signals when males were absent, and so the female signal can be also considered as a call and not only an answer, as usually pointed out in stoneflies.  相似文献   

3.
The male and larva of Protonemura cressa Zwick from Crete are described, the male is illustrated.  相似文献   

4.
1. The flight behaviour of adult merolimnic insects was studied on the first order limestone stream Leutra (Thuringia, Germany) using sticky traps. The focus of the present study was on testing the colonisation cycle hypothesis of Müller (1954) and on the small-scale dispersal of adult merolimnic insects. 2. A high number of sticky traps was used to guarantee a proper statistical analysis of the data and exclude effects of the heterogeneous environment on flight behaviour. 3. The flight behaviour of Leuctra hippopus, Nemoura cambrica, Nemoura flexuosa, Protonemura nitida, Protonemura praecox (Plecoptera), and Baetis rhodani (Ephemeroptera) was studied. 4. Specific flight corridors were observed for P. praecox, Nemoura spp., L. hippopus and B. rhodani. 5. Comparison of the catches on sticky traps set perpendicular to the water showed no significant flight upstream in any of the taxa studied. Thus, the results do not support the hypothesis of the colonisation cycle.  相似文献   

5.
The feeding habits of 17 species of Nemouroidea stoneflies (belonging to the families Nemouridae, Leuctridae and Capniidae) from the north‐western Iberian Peninsula are described and quantified by means of gut content analyses. As a whole, fungi, followed by pollen (both from angiosperm and, in a lesser degree, Pinaceae), leaf fragments (CPOM), detritus and, more punctually, lichens and animal matter are the most common items found in their guts. Nevertheless, variations among species were observed. For a species with a flight period that extends throughout the year, Protonemura globosa, variations in the diet were noticed among seasons, with pollen being more important during the spring and summer period. Together with a few previous studies, the present one reaffirms that feeding is an important aspect of the adult life in males and females of Nemouroidea.  相似文献   

6.
In this study, we analysed the decomposition of trout carcasses in a low-order Apennine stream, with the aim to investigate the mass loss rate in a Mediterranean lotic system, and to examine the influence of microhabitats on the invertebrates colonising fish carcasses. In May 2003, we put 56 dead rainbow trout (Oncorhynchus mykiss) in the stream, placing seven sets (four trout each) in both riffle and pool habitats. At four dates, we removed one trout per set to measure its dry mass and determine the associated macroinvertebrate assemblage. Fifty-eight macroinvertebrate taxa colonised the carcasses, with significant differences between the erosive and depositional microhabitats. Riffle trouts hosted richer and denser colonist communities than pool trouts. Chironomidae, Serratella ignita, Habrophlebia sp., Dugesia sp. and Protonemura sp. were the five most abundant taxa. Decomposition was initially very rapid in both environments and then tapered off over time. The mass loss rate was higher (k= –0.057 day–1) than that found in other studies. Higher Mediterranean temperatures probably increase the process. Although we found no significant difference between riffles and pools, mass loss was more regular in erosive habitats, underlining the importance of local, small-scale conditions. In small, low-order, heterotrophic streams, fish carcasses represent an important resource and shelter for rich and diversified invertebrate assemblages.  相似文献   

7.
Fruit shape is a quantitatively inherited character. In tomato, two major loci, sun and ovate, control fruit shape index, which is the ratio of fruit height over width. In this study, we measured many additional fruit shape features in three inter-specific F2 populations using the software application Tomato Analyzer. These populations were derived from varieties carrying elongated fruit but for which the major shape loci differed. We compared the effect of the major fruit shape loci with overall shape, as well as with the distal and proximal end shape features in each population. sun and ovate represented the largest effect on fruit shape in the Howard German and Sausage F2 populations, respectively. The largest effect QTL in the Rio Grande population carrying neither sun nor ovate, were fs8.1 on chromosome 8 and tri2.1/dblk2.1 on chromosome 2. These latter loci were also segregating in the other two populations, thus indicating common regions that control shape across the three populations. The phenotypic analyses showed that sun and ovate contributed to almost all aspects of shape such as the distal and proximal end features. In Rio Grande however, the largest effect QTL did not control all aspects of shape and the distal and proximal features were distinctly controlled in that population. Combined, our results implied that within the cultivated tomato germplasm pool the largest effect on elongated fruit shape was controlled by a combination of the loci sun, ovate, fs8.1 and tri2.1/dblk2.1. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

8.
A total of 29 species of stoneflies (Plecoptera) from 7 families were found in Belarus: Perlodidae—6, Perlidae—1, Chloroperlidae—3, Taeniopterygidae—2, Nemouridae—11, Capniidae—2, and Leuctridae—4 species. The fauna is fairly diverse and includes a number of rare species in Belarus and other European countries: Diura bicaudata, Marthamea vitripennis, Isoptena serricornis, Xanthoperla apicalis, Brachyptera risi, Protonemura intricata, Nemoura cambrica, Nemoura marginata, and Capnia bifrons.  相似文献   

9.
Resource dynamics and detritivore production in an acid stream   总被引:2,自引:0,他引:2  
1. Life history patterns and production of eight shredder‐detritivore species were studied in relation to the detritus dynamics of a small acidic stream in England. Mean annual detritus inputs (direct and lateral sources combined) were approximately 400 g m?2 year?1 and showed significant seasonal and annual variation. 2. Detritus standing stock did not increase significantly during times of high input, reflecting low retention efficiency. However, the mean detritus standing stock was relatively large (108 g m?2) reflecting a slow decomposition rate typical of acid streams. 3. Four species were univoltine with highly synchronous patterns of emergence and recruitment (Leuctra inermis, Leuctra hippopus, Capnia vidua and Amphinemura sulcicollis). Two species were univoltine with extended patterns of emergence and recruitment (Nemoura cinerea, Potamophylax cingulatus). Leuctra nigra was apparently semivoltine, while Protonemura meyeri showed two successive cohorts in the second year of the study, suggesting either bivoltinism or cohort splitting. 3. Secondary production of the dominant shredders was 1.67 g m?2 year?1 in 1997 and 1.99 g m?2 year?1 in 1998, which is low compared with other small European streams. This was probably because of an impoverished invertebrate community and poor food quality associated with acid conditions. Food availability probably did not account for the low production as the detritus standing stock far exceeded the estimated shredder ingestion of 42–50 g m?2 year?1. 4. Despite low overall shredder production, species‐specific production was high, possibly because of competitive release in this species‐poor acid stream. Periods of high production and growth showed no relationship with detritus availability but were closely related to life history.  相似文献   

10.

Background  

Grafting is a widely used technique contributing to sustainable and ecological production of many vegetables, but important fruit quality characters such as taste, aroma, texture and shape are known for years to be affected by grafting in important vegetables species including pepper. From all the characters affected, fruit shape is the most easily observed and measured. From research in tomato, fruit shape is known to be controlled by many QTLs but only few of them have larger effect on fruit shape variance. In this study we used pepper cultivars with different fruit shape to study the role of a pepper Ovate-like gene, CaOvate, which encodes a negative regulator protein that brings significant changes in tomato fruit shape.  相似文献   

11.
Aside from use as estimates of body mass dimorphism and fore to hind limb joint size comparisons, postcranial elements have not often contributed to assessments of variation in Australopithecus africanus. Meanwhile, cranial, facial, and dental size variation is interpreted to be high or moderately high. Further, the cranial base and face express patterns of structural (shape) variation, which are interpreted by some as evidence for the presence of multiple species. Here, the proximal femur is used to consider postcranial size and shape variation in A. africanus. Original fossils from Makapansgat and Sterkfontein, and samples from Homo, Pan, Gorilla, and Pongo were measured. Size variation was assessed by comparing the A. africanus coefficient of variation to bootstrapped distributions of coefficient of variation samples for each taxon. Shape variation was assessed from isometrically adjusted shape variables. First, the A. africanus standard deviation of log transformed shape variables was compared to bootstrapped distributions of logged standard deviations in each taxon. Second, shape variable based Euclidean distances between fossil pairs were compared to pairwise Euclidean distance distributions in each reference taxon. The degree of size variation in the A. africanus proximal femur is consistent with that of a single species, and is most comparable to Homo and Pan, lower than A. afarensis, and lower than some estimates of cranial and dental variation. Some, but not all, shape variables show more variation in A. africanus than in extant taxa. The degree of shape difference between some fossils exceeds the majority of pairwise differences in the reference taxa. Proximal femoral shape, but not size, variation is consistent with high estimates of A. africanus cranial variation.  相似文献   

12.
SUMMARY. 1. Egg development and larval growth of Protonemura intricata (Ris, 1902) (Plecoptera: Nemouridae) were studied in the laboratory and in the Breitenbach, a small stream-in Germany (F.R.G.). 2. The mean number of eggs in batches collected from the field was 627 (S=314). 3. Mean batching success in the laboratory was 60–100% at 2–18°C. Cumulative hatch in individual batches could be described by asymmetrically sigmoid curves. The length of the hatching period was positively correlated with the length of the incubation period. 4. The incubation period of I', intricata normally consists of an initial dormancy followed by subsequent development. The length of embryonic development (Y. days) is strongly inversely temperature (T, °C) dependent and can be described by the equation: 5. The length of dormancy is dependent on oviposition dale, and is shorter the later that the eggs are laid. It also depends on temperature during incubation and is increased by rising temperatures. As a consequence, larvae hatch more or less synchronously in the field during autumn. Total incubation period, i.e. dormancy and actual development, exhibits a complex dependence on both incubation temperature and oviposition date. Under constant laboratory temperatures, a late sharp fall in temperature can terminate dormancy earlier. 6. Photoperiod probably induces dormancy and may already act on the last larval instars of the parent generation. The dormancy of P. intricata is classified as an oligopause (Müller. 1970, 1976). 7. In the laboratory. P. intricata larvae from early batches with long dormancy grew faster than larvae from late batches with direct development. Final size was the same in both cases. This acted against the population synchrony induced through egg dormancy. Benthos samples suggest the same in the field. 8. Avoidance of the suboptimal summer conditions in streams by the cold stenothermous P. intricata is suggested to partly explain the success of the species, which contributes more to total emergence biomass than do other Plecoptera in the Breitenbach.  相似文献   

13.
The ulstrastructural study on Porphyridium aerugineum showed vesicles in the peripheral cytoplasm which contain fibrous material similar in appearance to the cell sheath. In most respects the morphology of P. aerugineum, a freshwater form, is very similar to that of P. cruenturn, a marine species. However, there is a marked difference in the shape of the phycobilisomes which are attached to the chloroplast lamellae. In P. cruentum the phycobilisomes are always spherical or oblate, whereas in P. aerugineum they are disk shaped. The possibility is considered that the shape of the phycobilisomes may be determined by the phycoerythrin and phycocyanin content.  相似文献   

14.
Cultivated tomato (Lycopersicon esculentum) encompass a wide range of fruit shape and size variants. This variation can be used to genetically dissect the molecular basis of ovary and fruit morphology. The cultivar Long John displays an extremely elongated fruit phenotype, while the wild relative Lycopersicon pimpinellifolium LA1589 produces fruit that are nearly perfect spheres, typical of wild tomatoes. Quantitative trait mapping of an F2 population between Long John and LA1589 revealed four fruit shape QTLs, located on chromosomes 2, 3, 7 and 11. The primary role of the fruit shape QTL located on chromosome 7, ljfs7, is to control pericarp elongation. The primary role of the fruit shape QTLs on chromosome 2, 3 and 11 (ljfs2, ljfs3 and ljfs11, respectively) is to control pear shape, measured as the eccentricity index. QTL map position and the effect of the loci on fruit shape suggested that ljfs2 and ljfs7 are allelic to the well-studied fruit shape loci ovate and sun, respectively. ljfs3 and ljfs11 map near the previously identified, but less characterized, fruit shape loci fs3.2 and fs11.1, respectively. This result suggests that most of the variation in tomato fruit shape is controlled by a few major QTLs. Although eccentricity and pericarp elongation were largely controlled by independent growth processes, significant interactions were detected between all four fruit shape loci in the control of eccentricity. This indicates that the three eccentricity loci, ljfs2, ljfs3 and ljfs11, epistatically control the same developmental process, while ljfs7 had a pleiotropic effect on eccentricity. Received: 27 March 2001 / Accepted: 7 May 2001  相似文献   

15.
A modified bootstrapping procedure is described by means of which standard errors and confidence limits may be determined for the Penrose shape coefficient. This method is then applied to odontometric data derived from four closely related groups of primates: Cercopithecus aethiops pygerythrus, C. a. sabaeus,St. Kitt’s green monkey (derived from C. a. sabaeus),and C. a. centralis.Although statistically significant distances were found to exist between these groups, one shape coefficient was significantly greater than the others: that between C. a. pygerythrusand C. a. centralis.Low levels of sexual dimorphism characterized the shape coefficients, with distances based on mandibular teeth being greater than those derived from maxillary teeth.  相似文献   

16.
Laboulbenia coneglanensis isolated from Japanese harpaline carabids is described and photographed. It is compared morphologically withL. flagellata from Japan and Europe, which is similar in appearance. The most important difference between the two species is in antheridial character and host range. Other characters such as coloration, perithecial shape, especially the shape of the perithecial apex, and size of ascospores are also useful for distinction.Laboulbenia ophoni var.dilatata described by Maire (1920) is regarded as a synonym ofL. coneglanensis.  相似文献   

17.
Eight species of the genus Monhystrella, six of which are new to science, are described from bottom samples collected from three lakes, two rivers and a hot spring in Ethiopia. Monhystrella hoogewijsi n. sp. is identified by a distinctive bulge on the lip region, position of the amphids, offset and well developed single pharyngeal terminal bulb, tail shorter than vulva-anus distance, tail elongate-conoid for two-thirds of its length, and by the shape and size of the spinneret outlet; M. jacobsi n. sp. by its slender body, distinctively offset and distended lip region, indistinct and weakly expanding single terminal pharyngeal bulb, and shape and size of the tail and spinneret outlet; M. arsiensis n. sp. by its single terminal pharyngeal bulb, position of amphids, shape and length of tail and spinneret outlet; M. woitorum n. sp. by its hemispherical lip region, double terminal pharyngeal bulb, shape and length of the spinneret outlet, and shape and length of tail; M. ethiopica n. sp. by its bipartite stoma, size of amphid in relation to corresponding body width, filiform tail and shape and length of spinneret outlet. M. atteae n. sp. differs from all known Monhystrella species in having an inflated cap-like lip region and fine crystalloid bodies. M. macrura (de Man, 1880) Andrássy, 1981 and M. lepidura altherri (Juget, 1969) Jacobs, 1987 are reported from Ethiopia for the first time. Crystalloid bodies in the genus Monhystrella is reported here for the first time. Also the presence of a hyaline coelomocyte next to the germinal zone of the reproductive system is reported for the first time in the genus here in all eight species. The structures used in the taxonomy of the genus are reviewed.  相似文献   

18.
A nematological survey of Belgium revealed four species of Aphanolaimus, two known ones, A. attentus de Man, 1880 and A. aquaticus Daday, 1894, and two new ones. A. pseudoattentus n.sp. resembles A. attentus in many respects but can easily be distinguished by the greater body length, the head shape, the shape of the amphideal fovea and the longer cephalic setae. A. deconincki n.sp. is characterized by its head shape, shape of amphideal fovea, posterior origin of lateral field and large number of body annules.  相似文献   

19.
Cephalaria kleinii Ranjbar & Z. Ranjbar sp. nova from Iran is described and illustrated. It is confined to Mazandaran province in northern Iran. The new species is closely related to C. kotschyi Boiss. & Hohen., but differs from it by its abaxial leaves colour, its basal leaves shape, dissection and petiole length, by the shape of apices of lateral and terminal segments of the cauline leaves, by the shape of apices of lateral and terminal segments of the upper leaves and by peduncle length. Furthermore, C. axillaris is resurrected and lectotypes are designated for C. axillaris and C. kotschyi for the first time.  相似文献   

20.
We previously identified fs10.1 as a major QTL controlling fruit shape (index of length to width) in an interspecific F2 cross of Capsicum annuum (round fruit) × C. chinense (elongated fruit) in pepper. To more precisely map and characterize the QTL, we constructed near-isogenic lines for fs10.1 and mapped it in a BC4F2 population. In this population, fs10.1 segregated as a Mendelian locus and mapped 0.3 cM away from the closest molecular marker. We further verified the effect of fs10.1 in an F2 population from an independent cross between elongated- and conical-fruited parents. To identify additional allelic variation at fruit shape loci, we screened an EMS-mutagenized population of the blocky-fruited cv. Maor and identified the mutant E-1654 with elongated fruit. This fruit shape mutation was mapped to the fs10.1 region and was determined to be allelic to the QTL. By measuring fruit shape of near-isogenic lines for fs10.1 during fruit development, we found that the shape of the fruit is determined primarily in the first 2 weeks after anthesis. Histological measurements of cell size and cell shape in pericarp sections of fruits of the isogenic lines throughout fruit development indicated that the shape of the fruit is determined primarily by cell shape and that the development of fruit shape is correlated with cell shape.  相似文献   

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