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1.
During recent cruises aboard RV Polarstern in the Antarctic Peninsula region, a new species of benthic octopodid was discovered whose generic affinities based on morphological characteristics were uncertain. Molecular sequence analysis of six mitochondrial and nuclear genes allows this species to be placed with confidence within the genus Pareledone. The species is described herein and morphological diagnostic characters are provided for its identification.  相似文献   

2.
Soil samples and museum collections were analysed from all zoogeographic regions of the world. From this material eleven new species of Ortheziola?ulc are described from Africa and the U.K., five additional species are redescribed and a key is presented for the identification of all sixteen species. A slightly modified concept of the genus is presented and several new characters are given as diagnostic of the genus. A phylogenetic hypothesis is given based on analysis of the morphological features of adult females. Results show that Ortheziola is most diverse in eastern Africa where relatively more advanced species occur. Basal species occur primarily in western Africa and Asia.  相似文献   

3.
Three cryptic species of Ceratopteris thalictroides, named the south type, the north type and the third type, were examined for their morphological characteristics, using sporophytes cultivated under common conditions. The discriminant analysis for leaf characters followed by one-way layout ANOVA or Kruskal–Wallis test for selected combinations of characters revealed that the following characters may be effective for identifying the three types: the relative lengths of stipe to blade and to pinna, the degree of dissection, the segment densities on rachis and pinna rachis, and the elongation degree of ultimate segments. The number of annulus cells on sporangia also proved to be a possible distinguishing character. As morphological data were obtained from a limited number of cultivated sporophytes, they are regarded as not definitive, but only referential diagnostic characters of the types and should be utilized not solely, but collectively, to avoid identification errors of the types. An identification trial using herbarium specimens proved these diagnostic characters to be useful to a considerable degree. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

4.
Two new species of Scrophularia L. sect. Tomiophyllum Benth., S. attariae Ranjbar & Rahchamani and S. maharluica Ranjbar & Rahchamani, are described and illustrated from Fars Province, south Iran. The diagnostic morphological characters of these species and closely related taxa are discussed. The distribution, ecology and conservation status of the new species are also described. The value and utility of stem indumentum and leaf stomata is evaluated as an additional source of information for their taxonomy. Finally, an identification key and distribution map for the new taxa and related species are presented.  相似文献   

5.
与传统的连续检索表相比,基于计算机等数字终端的多通道交互式检索表具有很多优势,如易于携带、实时更新、界面直观、使用方便、用户广泛、产生新数据集且便于研究以及能够推动分类学知识的普及等。本文以兰科植物为例介绍了交互式检索表的特点、程序建立和应用。兰科植物是生物多样性保育的旗舰类群,具有很强的观赏和药用价值,但中国兰科植物种类繁多,分类困难。我们在自主研发交互式检索表软件MagIden的基础上,以《中国植物志》和Flora of China的描述为依据,制作了中国兰科植物交互式电子检索表,为分类学研究者和爱好者提供了一个新的、鉴定中国兰科植物的中英文双语工具;同时,交互式检索表生成的MVSP和Bayes形态特征数据集可用于聚类分析和分支分类学研究。交互式检索表在数据积累、更新和分析利用等方面具有独特的优势,是提高传统植物分类学研究与应用效率的重要工具。  相似文献   

6.
The new species Impatiens brittoi (Balsaminaceae) allied to I. herbicola Hook. f., is described from the Idukki biodiversity zone of the Western Ghats of India. Detailed notes on morphology, key diagnostic characters, distribution, pollen morphology, conservation status and colour photographs are provided for the identification of the new species.  相似文献   

7.
Comparative analysis of morphometric characters of surman goby Neogobius cephalargoides and of two subspecies of ginger goby N. eurycephalus is made. Characteristics liable to size variation and sex dimorphism are revealed. Independence of the investigated species and the diagnostic value of characters previously suggested for classification are confirmed. The obtained data confirm isolation of north-western populations of ginger goby as a separate subspecies N. eurycephalus odessicus and suitability of three meristic characters for differentiation of the subspecies: the number of rays in the second dorsal fin and anal fin and the number of transverse rows of scales.  相似文献   

8.
Additional diagnostic characters of the three-dimensional structure of the male genitalia revealed with the use of scanning electron and light microscopy allowed elaborating a key to Aedes species from northwestern Russia. The key includes 29 species of 5 Aedes subgenera known or possibly occurring in the region.  相似文献   

9.
ABSTRACT

Larvae of the invasive mosquito Culex quinquefasciatus Say are morphologically similar to those of the native Culex pervigilans Bergroth, yet distinguishing these species can be hampered by morphological variations in Cx. quinquefasciatus. We present detail about the extent of these variations in an urban population of Cx. quinquefasciatus in Auckland. To aid in identification of this exotic species, we provide images of key diagnostic characters and some observed exceptions to these. Details regarding variation in diagnostic characters for < 3rd instar and 3rd/4th instar larvae are given. Of the nine characters used for identification, three were highly consistent (dorsal papillae, mantle plate, pecten teeth); each observed in > 90% of larvae, although these characters were not always visible. Other characters were less reliable, for instance, the expected position of seta 1a-S in relation to the pecten teeth was observed in < 10% of larvae. Further exploration of regional morphological variation in both Cx. quinquefasciatus and Cx. pervigilans is recommended, ideally with associated molecular characterisation.  相似文献   

10.
Lepidaploa belongs to tribe Vernonieae, one of the most complex tribes of Asteraceae, and the relationships within Lepidaploa and among related genera are poorly understood. Microcharacters may be of taxonomic value and may be used in the identification of taxa at different ranks. To evaluate the reliability of microcharacters as taxonomic markers in this group, we analysed the micromorphology of phyllaries, florets and cypselae in detail in 23 species of Lepidaploa .The species were studied using stereo, light, and scanning electron microscopy. Eight trichome types (eglandular and glandular) were observed on phyllaries, florets and cypselae, in addition to crystals, idioblasts and other microstructures. The results demonstrates that the ocurrence of different combinations of trichome types and crystals, presence of a stylar basal node, idioblasts and glandular apical anther appendages are highly useful to differentiate between related species of Lepidaploa and a diagnostic key using these characters is presented. However, these characters are not of much use to distinguish between closely related genera of Vernonieae since most characters appear homeoplasic and are found in representatives of different genera.  相似文献   

11.
Aphids of the species Cryptomyzus alboapicalis (Theobald, 1916) and Cryptomyzus leonuri Bozhko, 1961 are very similar morphologically, although exploit different host plants (Lamium album and Leonurus cardiaca, respectively). Morphological characters proposed for the separation of this species couple in the identification key to European Cryptomyzus species appeared to be of little discriminatory power when applied to apterous viviparous females from clonal lineages, whilst alate viviparous females of C. leonuri were not included in the key at all. The aim of this study was to find reliable morphological characters and their combinations for the separation of apterous and alate viviparous females of C. alboapicalis and C. leonuri. Forward stepwise discriminant analysis based on characters without statistically significant (P < 0.05) correlation (|r| ≥ 0.50) with body length resulted in canonical functions enabling correct classification of 95–100% of specimens from clonal lineages involved in the analysis with a priori specified group membership. The post hoc classification gave 95–100% correct identification of individuals from clonal and 85–100% from field-collected samples. The discriminative values of single morphological characters and canonical functions are discussed and modified key for the morphological identification of C. alboapicalis and C. leonuri apterous and alate viviparous females is suggested.  相似文献   

12.
Based on 100 species representative of the four genera, we scored 290 herbarium specimens for a number of morphological characters. The data were subjected to canonical discriminant analysis using characters different from those in the identification key to these genera byBaum, Yen, andYang (1991). These characters collectively support the four groupsAgropyron, Kengyilia, Roegneria, andElymus as previously defined. The four groups are also supported by the linear discriminant function with an overall rate of 83% correct classification. Length of lemma awn was found to be an additional diagnostic character asAgropyron andKengyilia have lemma awns shorter than 5 mm, whereasRoegneria andElymus have longer lemma awns with very few exceptions. Length of glume awns is also a useful supplementary generic diagnostic.Agropyron andElymus have glume awns, whereas the majority of species ofKengyilia and more than half of the species ofRoegneria lack them. If a glume awn is present it is usually not longer than 1 mm.  相似文献   

13.
14.
An identification key to 29 valid species of Hoplolaimus is given. A compendium of the most important diagnostic characters for use in identification of species is included as a practical alternative and supplement to the key. Diagnosis of Hoplolaimus is emended and lists of species of the genus, their synonymies, species inquirendae, nomina nuda, and species transferred to other genera are given. Hoplolaimus sheri, H. chambus, H. casparus, and H. capensis are recognized as valid species.  相似文献   

15.
Glyptomorpha baetica, G. discolor, G. gracilis, G. kasparyani, and G. pectoralis are recorded from Turkey. Glyptomorhpa baetica is new to the Turkish fauna. It was reared from a new host Sesamia nonagrioides (Noctuidae, Lepidoptera) and was redescribed. Its diagnostic characters are illustrated. An identification key is provided for nine species of Glyptomorpha of Turkey and adjacent regions. Distribution of each species is added.  相似文献   

16.
17.
The distribution of Daphniaspecies in tropical Africa is poorly known and understood. Daphniaare assumed rare in tropical regions, but systematic studies covering large areas are sparse. We sampled the active community (live zooplankton) and/or the dormant community (diapausing egg banks in the sediment) of 41 standing water bodies in Kenya in search for Daphnia.Overall the dormant communities yielded 11 species of Daphnia, a species richness more than twice the species richness found in the active communities. Dormant community species diversity better reflects the spatial, and particularly the temporal (multi-annual) variation in environmental conditions available to Daphniain these tropical standing waters. Hence, we suggest that the dormant community be taken into account when assessing local zooplankton diversity, especially in fluctuating tropical lake ecosystems, where the presence of each local Daphniaspecies in the active community may be strongly seasonal or erratic. Geographic distribution data from this study are supplemented with previous records of Daphniain East Africa to provide an overview of the known distribution of Daphniain Kenya and neighbouring countries. We also present a detailed key for morphological identification of the ephippia of the 11 Daphniaspecies encountered, complemented with photographs and drawings of diagnostic characters.  相似文献   

18.
Three new species of the mycophagous aleocharine genus Gyrophaena Mannerheim are described in Korea. The types and paratypes of the new species are designated. Illustrations of the diagnostic characters and habitus photographs of new species are provided with a key to Korean species of Gyrophaena.  相似文献   

19.
This paper documents the occurrence of the genus Umbilicaria in the neighbourhood of Admiralty Bay on King George Island in the maritime Antarctic. Nine species are reported from the area surveyed, with Umbilicaria kappeni being reported from King George Island for the first time. The occurrence of U. aprina, U. cristata and U. umbilicarioides on the island is confirmed and that of U. aprina is its first documented record from the maritime Antarctic. Fertile specimens of U. umbilicarioides are recorded for the first time from Antarctica. The area around Admiralty Bay seems to be one of the Antarctic regions with the highest diversity of Umbilicaria species. The diagnostic characters and distribution of each species are discussed. An updated key for identification of all the Antarctic species of the genus is provided.  相似文献   

20.
A key based on cyst and juvenile characters is given for identification of 12 valid Heterodera species in the H. avenae group. A compendium providing the most important diagnostic characters for use in identification of species is included as a supplement to the key. Cyst characters are most useful for separating species; these include shape, color, cyst wall pattern, fenestration, vulval slit length, and the posterior cone including presence or absence of bullae and underbridge. Also useful are those of second-stage juvenile characteristics including aspects of the stylet knobs, tail hyaline tail terminus, and lateral field. Photomicrographs of diagnostically important morphological features complement the compendium.  相似文献   

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