Cytogenetic studies in relation to taxonomy within the family Gryllidae (Orthoptera). I. Subfamily Gryllinae

1973 ◽  
Vol 51 (2) ◽  
pp. 179-186 ◽  
Author(s):  
H.-C. Lim ◽  
V. R. Vickery ◽  
D. K. McE. Kevan

Twelve species of Gryllinae were studied to determine the number, morphology and behavior of their chromosomes. The male diploid numbers ranged from 19 to 31. Gryllus campestris and a population of "G. bimaculatus" from Singapore showed anomalies in chromosome behavior and structure, including breaks, stickiness, C-mitosis, polyploidy, lagging, unequal segregation and non-disjunction in the former and many aberrations and loss of fertility in the latter. One or two B-chromosomes occurred in some individuals of G. veletis, the chromosome number of this species thus varying from 2n ♀ = 29 to 31. In the Gryllinae, karyotypic differences are shown to be more useful than chromosome number at the species level; differences in chromosome number are useful taxonomically at the generic level, when combined with differences in karyotypes.

Bothalia ◽  
1989 ◽  
Vol 19 (1) ◽  
pp. 125-132 ◽  
Author(s):  
J. J. Spies ◽  
E. J. L. Saayman ◽  
S. P. Voges ◽  
G. Davidse

Cytogenetic studies of 53 specimens of 14 species of the genus  Ehrharta Thunb. confirmed a basic chromosome number of 12 for the genus. Chromosome numbers for 13 species are described for the first time. The highest ploidy level yet observed in the genus (2n = lOx = 120) is reported for E. villosa var.  villosa. B chromosomes were observed in several specimens of four different species.


1988 ◽  
Vol 9 (3) ◽  
pp. 301-310 ◽  
Author(s):  
E. Solleder ◽  
M. Schmid

The karotypes of nine species of the family Agamidae were analyzed with various banding techniques and conventional cytogenetic stainings. Whereas the examined species of the genera Calotes and Leiolepis exhibit conservative karyotypes, the chromosome number and chromosome morphology varies considerably within the genus Agama. This is attributed to centric fusions between telocentric chromosomes and pericentric inversions within the chromosomes. None of the species demonstrated multiple quinacrine banding patterns in the euchromatic segments of the metaphase chromosomes. This is probably due to the special DNA organization in these organisms.


2017 ◽  
Vol 31 (5) ◽  
pp. 566 ◽  
Author(s):  
Michael G. Rix ◽  
Robert J. Raven ◽  
Barbara Y. Main ◽  
Sophie E. Harrison ◽  
Andrew D. Austin ◽  
...  

The Australasian spiny trapdoor spiders of the family Idiopidae (subfamily Arbanitinae) are revised at the generic level, using a multi-locus molecular phylogenetic foundation and comprehensive sampling of all known lineages. We propose a new family- and genus-group classification for the monophyletic Australasian fauna, and recognise 10 genera in four tribes. The Arbanitini Simon includes Arbanitis L. Koch, 1874 (61 species), Blakistonia Hogg, 1902 (one species) and Cantuaria Hogg, 1902 (43 species). The Aganippini Simon includes Bungulla Rix, Main, Raven & Harvey, gen. nov. (two species), Eucanippe Rix, Main, Raven & Harvey, gen. nov. (one species), Eucyrtops Pocock, 1897 (two species), Gaius Rainbow, 1914 (one species) and Idiosoma Ausserer, 1871 (14 species). The Cataxiini Rainbow and Euoplini Rainbow include just Cataxia Rainbow, 1914 (11 species) and Euoplos Rainbow, 1914 (12 species), respectively. Two distinctive new genera of Aganippini are described from Western Australia, and several previously valid genera are recognised as junior synonyms of existing genus-group names, including Misgolas Karsch, 1878 (= Arbanitis; new synonymy), Aganippe O. P.-Cambridge, 1877 (= Idiosoma; new synonymy) and Anidiops Pocock, 1897 (= Idiosoma; new synonymy). Gaius stat. rev. is further removed from synonymy of Anidiops. Other previously hypothesised generic synonyms are supported by both morphology and molecular phylogenetic data from 12 genes, including the synonymy of Neohomogona Main, 1985 and Homogona Rainbow, 1914 with Cataxia, and the synonymy of Albaniana Rainbow & Pulleine, 1918, Armadalia Rainbow & Pulleine, 1918, Bancroftiana Rainbow & Pulleine, 1918 and Tambouriniana Rainbow & Pulleine, 1918 with Euoplos. At the species level, the identifications of Eucy. latior (O. P.-Cambridge, 1877) and I. manstridgei (Pocock, 1897) are clarified, and three new species are described: Bungulla bertmaini Rix, Main, Raven & Harvey, sp. nov., Eucanippe bifida Rix, Main, Raven & Harvey, sp. nov. and Idiosoma galeosomoides Rix, Main, Raven & Harvey, sp. nov., the latter remarkable for its phragmotic abdominal morphology. The Tasmanian species Mygale annulipes C. L. Koch, 1842 is here transferred to the genus Stanwellia Rainbow & Pulleine, 1918 (family Nemesiidae), comb. nov., Arbanitis mestoni Hickman, 1928 is transferred to Cantuaria, comb. nov. and Idiosoma hirsutum Main, 1952 is synonymised with I. sigillatum (O. P.-Cambridge, 1870), new synonymy. In addition to the morphological synopses and an illustrated key to genera, molecular diagnoses are presented for all nominal taxa, along with live habitus and burrow images to assist in field identification. The Australasian idiopid fauna is highly diverse, with numerous new species known from all genera. As a result, this study provides a taxonomic and nomenclatural foundation for future species-level analyses, and a single reference point for the monographic documentation of a remarkable fauna. http://zoobank.org/?lsid=urn:lsid:zoobank.org:pub:BACE065D-1EF9-40C6-9134-AADC9235FAD8


Author(s):  
Walia Gurinder Kaur ◽  
Chahal Sarabjit Singh ◽  
Singh Navdeep

Male germ cell chromosomes of Burmagomphus divaricatus, Burmagomphus pyramidalis and Burmagomphus sivalikensis of family Gomphidae have been investigated by using conventional staining, C-banding, silver nitrate staining and sequence specific staining. The species were collected from Punjab and Himachal Pradesh, India. All the species possess the chromosome number 2n = 23 which is the type number of the family. Terminal C bands and NOR’s are present at the autosomal bivalents and X chromosome is C positive and NOR rich in all the three species, while m bivalents show variation in distribution of C- heterochromatin and NOR’s. In the sequence specific staining, whole complement shows bright DAPI signals in B. divaricatus, bright CMA3 signals in B. pyramidalis and both DAPI and CMA3 signals in B. sivalikensis.


2018 ◽  
Vol 12 (2) ◽  
pp. 163-170
Author(s):  
Tiago Marafiga Degrandi ◽  
Jean Carlo Pedroso de Oliveira ◽  
Amanda de Araújo Soares ◽  
Mario Angel Ledesma ◽  
Iris Hass ◽  
...  

Kingfishers comprise about 115 species of the family Alcedinidae, and are an interesting group for cytogenetic studies, for they are among birds with most heterogeneous karyotypes. However, cytogenetics knowledge in Kingfishers is extremely limited. Thus, the aim of this study was to describe the karyotype structure of the Ringed Kingfisher (Megaceryletorquata Linnaeus, 1766) and Green Kingfisher (Chloroceryleamericana Gmelin, 1788) and also compare them with related species in order to identify chromosomal rearrangements. The Ringed Kingfisher presented 2n = 84 and the Green Kingfisher had 2n = 94. The increase of the chromosome number in the Green Kingfisher possibly originated by centric fissions in macrochromosomes. In addition, karyotype comparisons in Alcedinidae show a heterogeneity in the size and morphology of macrochromosomes, and chromosome numbers ranging from 2n = 76 to 132. Thus, it is possible chromosomal fissions in macrochromosomes resulted in the increase of the diploid number, whereas chromosome fusions have originated the karyotypes with low diploid number.


Crustaceana ◽  
1999 ◽  
Vol 72 (8) ◽  
pp. 781-816 ◽  
Author(s):  
Stefan Koenemann ◽  
John Holsinger

AbstractThe increasing number of world-wide discoveries of subterranean amphipods, especially during the last two decades, has led to additions of numerous new taxa in the stygobiont family Bogidiellidae s. lat. To date, the family is composed of 23 genera and 11 subgenera, and approximately 110 described species. However, given the uneven quality of generic and subgeneric diagnoses in the literature, there is considerable confusion regarding the status of some of the taxa at these levels. Even the family itself lacks a clear definition. In order to gain a better knowledge of the phylogeny of this group, a cladistic analysis, employing both PAUP 3.0s and MacClade, was performed on the genera and subgenera currently assigned to the Bogidiellidae s. lat. Supported by the results of this analysis, the taxonomic structure of this group is completely revised above the species level. The revision excludes 5 genera from the family, all remaining subgenera are elevated to generic level. Four taxa are split, resulting in 5 new genera. The family Bogidiellidae now consists of 33 genera. Die wachsende Zahl weltweiter Neuentdeckungen von Grundwasser-Amphipoden, insbesondere wahrend der letzten zwei Jahrzehnte, erweiterte die Stygobiontenfamilie Bogidiellidae s. lat., um zahlreiche neue Taxa. Bis heute sind in der Familie etwa 110 beschriebene Arten in 23 Gattungen und 11 Untergattungen zusammengefasst. Aufgrund der unterschiedlichen Qualitat diagnostischer Beschreibungen herrscht allerdings erhebliche Verwirrung hinsichtlich des taxonomischen Status einiger Gruppen. Sogar die Definition der Familie selbst ist relativ undeutlich. Um neue Einsichten in die Phylogenie der Bogidielliden s. lat., zu erhalten, fuhrten wir eine kladistische Analyse der Gattungen und Untergattungen unter Verwendung der Computerprogramme PAUP 3.0s und MacClade durch. Die Resultate dieser Analyse dienten als hilfreiche Erganzung bei der umfassenden taxonomischen Revision der Gattungen und Untergattungen. Funf Gattungen wurden aus der Familie entfernt und alle Untergattungen zu Gattungen erhoben. Das Aufspalten von vier Taxa resultierte in 5 neuen Gattungen. Die Familie Bogidiellidae besteht somit aus 33 Gattungen.


1975 ◽  
Vol 17 (2) ◽  
pp. 173-180 ◽  
Author(s):  
Armando Garcia V.

Chromosome number determinations were made on 137 collections of seven Persea species. Persea americana Mill., P. schiedeana Nees, and P. aff. cinerascens Rands, had a diploid number of 24 as reported earlier. The first chromosome counts for four species are reported. Persea hintonii Allen (2n = 48) is the first tetraploid species found in this genus. Persea indica (L.) Spreng. (2n = 24) is the first Old World species to have its chromosome number reported. Persea donnell-smithii Mez and P. pachypoda Nees also have the diploid number (2n = 24). One triploid (2n = 36) and one tetraploid (2n = 48) individual were found in P. americana. Based on stomatal size, their maternal plants were considered to be triploid and diploid, respectively.This is the first karyotype study in Persea and also in the family Lauraceae. The karyotype in Persea is asymmetric. The chromosomes range in size from 2.3 µm to 6.1 µm. Persea americana has one pair of satellited chromosomes, which is the largest pair, two metacentric pairs and nine submetacentric pairs. Two of the submetacentric pairs are highly heterochromatic and both are attached to the nucleolus. All the other species have karyotypes very similar to P. americana.


2017 ◽  
pp. 25
Author(s):  
Lina Ojeda-Revah ◽  
Beatriz Ludlow-Wiechers

The pollen of 15 genera and 36 species of the family Agavaceae were studied, based on Hutchinson' s classification. Observations were made with LM and SEM. Different taxonomical classifications are reviewed considering pollen morphology, geographical distribution, chromosome number and ovary position. From palynological point of view, Dahlgren et al., last classification agrees with the results obtained. Pollen samples studied show two levels of morphological behaviour: at an interespecific level there is little or no variation and at a generic level the following patterns are observed: a) semitectate and mainly monosulcate: Agave, Beschorneria, Dasylirion, Furcraea, Hesperaloii, Manfreda and Polianthes sometimes disulcate (Agavaceae, Agavoideae); b) tectate-perforate and monosulcate: Yucca (Agavaceae, Yuccoideae) and Dracaena americana (Dracaenaceae); c) tectate perforate to microreticulate and monosulcate to disulcate: Beaucamea, Calibamis and Nolina (Nolinaceae); d) intectate verrugate and monosulcate: Hasta (Funkiaceae); e) semitectate to tectate perforate and trichotomosulcate: Phormium (Phormiaceae); f) fosulate and monosulcate: Cordyline (Asteliaceae) and Dracaenafragans (Dracaenaceae) and g) psilate and ulcerate: Sansevieria (Dracaenaceae).


2016 ◽  
Vol 5 (03) ◽  
pp. 4902
Author(s):  
Afrin Nazli ◽  
Kamini Kumar*

Haworthia limifolia is a xerophytic plant belonging to the family Liliaceae and is indigenous to Africa. It is use extensively for its medicinal properties like antibacterial, antifungal properties and used for the treatment of sores, superficial burns, as a blood purifier and to promote pregnancy in women and cattles. In present investigation chromosomal behaviour of H. limifolia in meiosis was studied. In diplotene stage chiasmata was observed showing the possibilities of genetic recombination. Chromosome clumps were observed in diakinesis indicating sticky nature of chromosomes. Meiotic abnormalities like stickiness, precocious movement, formation of bridges and laggards were also reported in both meiosis I and II. A fairly high percentage of pollen sterility that is 73.41% was recorded resulting in failure of fruit formation. This plant could be designated as facultative apomict (Swanson, 1957) as the only means of reproduction found was asexual or vegetative.


Author(s):  
Lisa M. Diamond ◽  
Molly R. Butterworth ◽  
Ritch C. Savin-Williams

The present chapter provides a review of some of the primary psychological issues confronting sexual minorities (i.e., individuals with same-sex attractions and relationships). Our goal is to provide a flexible set of preliminary questions that can be used to help sexual-minority clients to articulate their own idiosyncratic experiences and give voice to their own unique needs. We begin by addressing two of the most common and important clinical issues faced by sexual minorities: generalized “minority stress” and acceptance and validation from the family of origin. We then turn attention to the vast—and vastly underinvestigated—population of individuals with bisexual attractions and behavior, who actually constitute the majority of the sexual-minority population, despite having been systematically excluded from most prior research. We review the increasing body of research suggesting that individuals with bisexual patterns of attraction and behavior actually face greater mental health risks than those with exclusive same-sex attractions and behavior, and we explore potential processes and mechanisms underlying this phenomenon, focusing particular attention on issues of identity development and transition over the life span. We conclude by outlining a number of areas for future clinically oriented research.


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