A karyological study of Allium rouyi Gautier (Liliaceae), a recently rediscovered endemic species from the south of Spain

A karyological study ofAllium rouyiGautier (Liliaceae), a recently rediscovered endemic species from the south of Spain

Karyological studies of some orophyte taxa of the genus Ranunculus L. from the Iberian Peninsula

Four Terminalia L. species namely, T. arjuna (Roxb.) Wight and Arn., T. bellirica (Gaertn.) Roxb., T. chebula Retz. and T. catappa L. were studied to evaluate the chromosomal relationship corresponding with their taxonomic characters. Analysis of mitotic metaphases showed that the somatic chromosome numbers and the centromeric formulas of these species were 2n = 24 (16m + 8sm) for T. arjuna, 2n = 48 (36m + 12sm) for T. bellirica, 2n = 48 (46m + 2sm) for T. chebula and 2n = 24 (24m) for T. catappa. Two pairs of satellites were found in T. bellirica and T. catappa. Based on different karyological data, T. chebula was positioned in 1A, T. arjuna and T. catappa in 1B and T. bellirica in 2B. Based on comparative karyomorphological data, T. bellirica and T. arjuna presented more advanced features in comparison with T. chebula and T. catappa, which also correlated with the taxonomic characters in respect of the evolutionary point of view. Therefore, the present investigation effectively evaluated chromosomal relationships with morphological implications that conferred upon evolutionary changes among these four Terminalia species.

Study of the helminth fauna in eagle owl (Bubo bubo) in the south of Spain

Developmental potential was assessed in 8 intra-specific and 20 inter-specific hybrid clones obtained by fusion of embryonic stem (ES) cells with either splenocytes or fetal fibroblasts. Number of chromosomes derived from ES cells in these hybrid clones was stable while contribution of somatic partner varied from single chromosomes to complete complement. This allowed us to compare pluripotency of the hybrid cells with various numbers of somatic chromosomes. Three criteria were used for the assessment: (i) expression of Oct-4 and Nanog genes; (ii) analyses of teratomas generated by subcutaneous injections of the tested cells into immunodeficient mice; (iii) contribution of the hybrid cells in chimeras generated by injection of the tested cells into C57BL blastocysts. All tested hybrid clones showed expression of Oct-4 and Nanog at level comparable to ES cells. Histological and immunofluorescent analyses demonstrated that most teratomas formed from the hybrid cells with different number of somatic chromosomes contained derivatives of three embryonic layers. Tested hybrid clones make similar contribution in various tissues of chimeras in spite of significant differences in the number of somatic chromosomes they contained. The data indicate that pluripotency is manifested as a dominant trait in the ES hybrid cells and does not depend substantially on the number of somatic chromosomes. The latter suggests that the developmental potential derived from ES cells is maintained in ES-somatic cell hybrids by cis-manner and is rather resistant to trans-acting factors emitted from the somatic one.

The phylogenetic relationships among five species of sculpins, including Myoxocephalus stelleri, M. brantii, M. jaok, M. ochotensis, and Megalocottus platycephalus, were estimated from the sequence variability of the mtDNA cytochrome b (cytb) and cytochrome oxidase 1 (CO1) genes. Analysis of the topologies of combined phylogenetic trees showed that all of the morphologically described species from different genera represented monophyletic groups with high support of branch robustness. Haplotypes with different karyotypes from different geographical localities with an intragroup nucleotide diversity of 43% were combined into the M. stelleri clade. All of the species (except for M. stelleri from the Sea of Japan and the Okhotsk Sea coast of the Hokkaido Island) were characterized by relatively low values of the intragroup variation, along with high values of interspecific variation of mtDNA-encoded markers. Studies of the M. stelleri karyotypes using Ag-banding showed that karyotypes of the individuals from the Sea of Japan and Okhotsk differed not only in the number of chromosomes (2n) but also in the number of active nucleolus organizers (NO) and stained NO blocks, calling into question whether they belong to a single species. The observed discrepancy between the phylogenetic topologies and karyological data is discussed in relation to the informative capacity of mtDNA fragments and the phenomenon of intraspecific chromosomal polymorphism.

The history and value of cytogenetic features for addressing questions of the evolution and systematics of tapeworms (Cestoda) are briefly reviewed along with instructions for collecting karyological data. As a supplement to worm morphology, chromosome number and morphology have been helpful in determining the systematic status of some genera in the Diphyllobothriidae and species in the Bothriocephallidea. In addition, many new techniques for chromosome analysis have been recently applied in morphological and molecular studies of invertebrates, including tapeworms. Methods of molecular karyology, fluorescence in situ hybridisation, and chromosomal location of satellite DNA, microsatellites or histone genes may also provide useful data to inference of taxonomic relationships and for revealing trends or general lines of chromosome evolution. However, as karyological data are available only for few tapeworms, they are seldom an integral part of evolutionary and taxonomic studies of cestodes. A primary reason for this lack of karyological data may lie in general difficulties in working with tapeworm chromosomes. To address these problems, herein we present a well-tested, step-by-step illustrated guide on the fixation of tapeworm material and preparation of their chromosomes for cytogenetic studies. The technique requires standard glassware, few reagents and simple equipment such as needles; it can also be used on other neodermatan flatworms.

A voluminous information is available on karyological studies of fishes; however, limited efforts were made for compilation and curation of the available karyological data in a digital form. ‘Fish Karyome’ database was the preliminary attempt to compile and digitize the available karyological information on finfishes belonging to the Indian subcontinent. But the database had limitations since it covered data only on Indian finfishes with limited search options. Perceiving the feedbacks from the users and its utility in fish cytogenetic studies, the Fish Karyome database was upgraded by applying Linux, Apache, MySQL and PHP (pre hypertext processor) (LAMP) technologies. In the present version, the scope of the system was increased by compiling and curating the available chromosomal information over the globe on fishes and other aquatic organisms, such as echinoderms, molluscs and arthropods, especially of aquaculture importance. Thus, Fish Karyome version 2.1 presently covers 866 chromosomal records for 726 species supported with 253 published articles and the information is being updated regularly. The database provides information on chromosome number and morphology, sex chromosomes, chromosome banding, molecular cytogenetic markers, etc. supported by fish and karyotype images through interactive tools. It also enables the users to browse and view chromosomal information based on habitat, family, conservation status and chromosome number. The system also displays chromosome number in model organisms, protocol for chromosome preparation and allied techniques and glossary of cytogenetic terms. A data submission facility has also been provided through data submission panel. The database can serve as a unique and useful resource for cytogenetic characterization, sex determination, chromosomal mapping, cytotaxonomy, karyo-evolution and systematics of fishes.Database URL:http://mail.nbfgr.res.in/Fish_Karyome

Chromosome number, size and morphology of five taxa of the genus Glycyrrhiza growing naturally in Turkey were investigated. Permanent slides were made by using the standard liquid nitrogen method. Karyotypes were determined using Image Analysis System (Bs200Pro). In addition, the karyotype asymmetry of each taxa was evaluated by different methods: TF%, AsK%, Rec and Syi, A1, A2, A, AI and Stebbins classification. Correlations between the karyotype asymmetries of the different taxa were calculated. Two different chromosome numbers were found in the studied taxa; 2n = 16 in Glycyrrhiza echinata, G. glabra, G. flavescens subsp. flavescens, G. flavescens subsp. antalyensis and 2n = 14 in G. asymmetrica. The karyological data were evaluated with the NTYSY software package and used to create a dendrogram. The results were compared with previous cytological data. Photos of the taxa in their natural environment are also presented.

Are polyploids really evolutionary dead-ends (again)? A critical reappraisal of Mayrose etal. ().

The faunal succession of Japanese Quaternary mammals is described within the stratigraphic framework provided mainly by KAMEI, KAWAMURA and TARUNO (1988). Descriptions are given separately for Hokkaido, Honshu-Shikoku-Kyushu and the Ryukyu Islands.In Hokkaido, Pleistocene mammalian remains are too scarce to provide a detailed faunal succession, but abundant remains of Holocene age suggest that the fauna was almost identical to that of the present day. Large mammals recorded for the Late Pleistocene are therefore considered to have been extinct by the Holocene.In Honshu-Shikoku-Kyushu, the Early Pleistocene fauna is of temperate forest type, and related to those of north China. Almost all the components are, however, assigned to extinct endemic species. The Middle Pleistocene fauna is characterized by the presence of extant species. In fact, they exceed half of the components in the middle Middle Pleistocene fauna, and are still more common in the later faunas. This fauna is also dominated by temperate forest elements and endemic species. Immigration from south China in the middle Middle Pleistocene is more limited than previously thought, and only a few forms migrated from north and northeast China in the late Middle Pleistocene. The Late Pleistocene fauna is basically identical with that of the Middle Pleistocene except for the absence of several extinct species and several exotic species which still survive in other regions. Although the fauna seems to have been isolated from those of the adjacent continent in the early Late Pleistocene, immigration of large herbivores from the northern part of the continent was recognized in the late Late Pleistocene. Most of the extinct and exotic species were eliminated from the fauna between 20, 000 and 10, 000 years BP, and thus the fauna became almost identical with that of the present day by the early Holocene.In the Ryukyu Islands, Early and Middle Pleistocene faunas are almost unknown, while Late Pleistocene and Holocene ones are relatively well recorded. The Late Pleistocene fauna is of insular type, and includes several species endemic to the islands. Some of them are extinct species. From the end of the Pleistocene to the Holocene, insularity of the fauna was enhanced by the extinction of major species and by extreme reduction in habitat areas of the survivors.

The genus Pancratium, belonging to Amaryllidaceae, has widespread therapeutic utility mainly owing to presence of bioactive alkaloids. However, its taxonomical relationships remain inadequately explored, resulting in an ill-defined infra-generic classification. This necessitates further investigation using cytogenetic and molecular phylogenetic approaches, which can further clarify taxonomic relationships. Existing reports on such attributes are scattered across the literature, making the collation and consolidation of data a prerequisite for further analysis. The present review ascertained that cytogenetic characterization has been initiated in less than 50% of accepted Pancratium species, with no data for unplaced species. Most species exhibit a chromosome count of 2n=22 and n=11, suggesting widespread homoploidy, with dominance of asymmetric karyotype with x=11 as the most probable basic chromosome number. Nuclear genome size estimations are reported only in two species, with 2C values of 36.30 pg and 60.10 pg in P. illyricum and P. maritimum, respectively. Karyological studies have been done only in six species with mostly bimodal or graded asymmetric karyotypes and predominance of chromosomes with submedian to subterminal primary constrictions. Fluorochrome chromosome banding is reported only in P. illyricum and P. maritimum, both exhibiting CMA positive bands associated with nucleolar organizer regions identified by FISH. Thus, from the present review it is evident that the genus Pancratium exhibits widespread cytogenetic diversity with probable taxonomic utility but awaits the exploration of these traits in most species for further implications. Research on Mediterranean species using chloroplast non-coding DNA (cpDNA) sequences suggests the possible existence of a P. maritimum species complex. However, similar studies are limited in Asian species and entirely absent in Indian taxa, underscoring the need for further investigation. Correlation of such molecular phylogenetic analysis with karyological data and genome size can help in further elucidation of taxonomic relationships by establishing either distinctiveness or diversity of the established groups. However, such analysis is limited in literature and awaits further exploration.

In this study, the somatic chromosome numbers and karyotype analyses were determined for nine taxa that belong to three different genera of Senecioneae tribe. The studied taxa are; Senecio tauricolus V.A.Matthews, Senecio racemosus (M.Bieb.) DC., Senecio paludosus L., Senecio trapezuntinus Boiss., Senecio inops Boiss. & Balansa subsp. inops, Turanecio pandurifolius (K.Koch) Hamzaoglu, Turanecio hypochionaeus (Boiss.) Hamzaoglu, Turanecio eriospermus (DC.) Hamzaoglu, Tephroseris integrifolia (L.) Holub. subsp. aurantiaca (Hoppe ex Willd.) B.Nord. S. tauricolus, S. trapezuntinus, S. inops subsp. inops and T. hypochionaeus taxa are endemic to Turkey. The chromosomal variability in the tribe Senecioneae has observed the existence of four chromosome numbers: 2n = 38, 2n = 40, 2n = 46 and 2n = 80. The chromosome number 2n = 38 is a new record for Turanecio species. All taxa existed karyotypes measured by a set of median to submedian chromosomes and a smaller number of subterminal chromosome pairs. Also their karyotype asymmetry indices (TF %, As K %, Syi, Rec, A, A 1 and A 2) were calculated. The ideograms and detailed chromosome morphology measurements of the species were performed by the use of image analysis system (Bs200Pro). This is the first account of somatic chromosomes and karyotypes for the studied taxa except for S. paludosus. The research has contributed to the taxonomic revision of the tribe, Senecioneae, in Turkey.

Contributions to the karyological study of the genus Ranunculus L. subgenus Batrachium (DC.) A Gray from the Iberian Peninsula

1. Cytological examination ofD. annulatum, D. caricosum, D. nodosum andB. intermedia was undertaken. 2. Meiotic and somatic chromosome numbers observed namelyn = 20 and2n = 40 inD. annulatum are in confirmation with the observations of the previous workers. 3. Meiotic and somatic chromosome numbers inD. caricosum have been observed as 20 and 40 respectively for the first time as the somatic number reported by Krishnaswamy (1939) does not agree with the number reported here. 4. The somatic chromosome number inD. nodosum is 2n = 40. This is being reported for the first time. 5. No polyploidy was observed in the forms of the three species ofDichanthium studied. 6. InB. intermedia 40 chromosome type is being reported for the first time and the existence of 60 chromosome type is confirmed. 7. The existence of polyploidy has been observed inB. intermedia and the increase in chromosome number is associated with the increase in size and other characters.