A SYNOPSIS OF CYTOLOGICAL STUDIES IN GESNERIACEAE

2003 ◽  
Vol 60 (3) ◽  
pp. 425-447 ◽  
Author(s):  
M. MÖLLER ◽  
M. KIEHN

Our knowledge of cytological data published on members of the family Gesneriaceae is summarized and critically evaluated in the light of current taxonomic treatments and phylogenetic hypotheses. There are about 1000 published chromosome counts, covering 56% of the genera but only 18% of the species. In particular the New World tribes Beslerieae and Napeantheae and the Old World tribe Didymocarpeae are underexplored at generic level. In Gesneriaceae chromosome data are a valuable source of taxonomic characters. From our current knowledge of the phylogenetic relationships in the family we know that basic chromosome numbers in the New World subfamily Gesnerioideae appear to be rather conserved, but that a more complex pattern of genome evolution seems to be present among the Old World tribes. Both polyploidy and dysploid changes have played a significant role in the evolution of the family. However, the number of species for which both cytological and molecular data are available is at present too low to reach firm conclusions on ancestral basic chromosome numbers, particularly for the Old World group. To facilitate wider access to cytological data on the Gesneriaceae, a website has been developed (http://www.rbge.org.uk/rbge/web/search/index.jsp), which is introduced in this paper.

Zootaxa ◽  
2019 ◽  
Vol 4668 (3) ◽  
pp. 301-328
Author(s):  
TERRY A. WHEELER ◽  
BRADLEY J. SINCLAIR

Paraleucopidae Wheeler fam. nov. is proposed for the previously unplaced New World genera Paraleucopis Malloch, Mallochianamyia Santos-Neto and Schizostomyia Malloch and undescribed Australian species. A key to genera of Paraleucopidae is provided. Paraleucopis is revised and includes nine species: P. auripes Wheeler & Sinclair sp. nov. (type locality: Andalgala, Argentina); P. bispinosa Wheeler & Sinclair sp. nov. (type locality: Socos, Coquimbo, Chile); P. boharti Wheeler & Sinclair sp. nov. (type locality: Andalgala, Argentina); P. boydensis Steyskal (type locality: nr. Palm Desert, California, USA); P. corvina Malloch (type species of genus; type locality: New Mexico, USA); P. mexicana Steyskal (type locality: Kino Bay, Mexico); P. nigra Wheeler & Sinclair sp. nov. (type locality: Portal, Arizona, USA); P. paraboydensis Wheeler & Sinclair sp. nov. (type locality: Willis Palms Oasis, California, USA); P. saguaro Wheeler & Sinclair sp. nov. (type locality: Usery Mtn Park, Arizona, USA). A key to the species of Paraleucopis is provided. The distribution of Paraleucopis is disjunct, with six species in the western United States and northwestern Mexico and three species in northern Chile and northern Argentina.                The sister group and superfamilial assignment of the Paraleucopidae cannot be established based on current knowledge although the family has affinities to some families of the Asteioinea sensu J.F. McAlpine. A well-supported hypothesis on the relationships of the families of the Acalyptratae will be required before the sister group relationships of Paraleucopidae can be determined. 


2012 ◽  
Vol 69 (2) ◽  
pp. 323-345 ◽  
Author(s):  
F. Christie ◽  
S. Barber ◽  
M. Möller

Chromosome numbers were determined in 23 accessions representing 21 species hitherto belonging toChirita(Gesneriaceae), a genus that has recently been remodelled and split into five different genera:Damrongia,Henckelia,Liebigia,MicrochiritaandPrimulina. The previously monotypicPrimulina tabacumwas also investigated. Counts for 19 species were new, two were confirmatory and two gave different numbers from previously published counts. The results here, together with previously published cytological data for the erstwhile genusChirita, were analysed in the light of the taxonomic revision of the genus and published phylogenetic data.Chiritawas originally highly heterogeneous in chromosome numbers, including seven different somatic numbers, 2n= 8, 18, 20, 28, 32, 34 and 36. Among the five remodelled genera,Henckeliawas found to be as equally heterogeneous as the erstwhileChirita,Microchiritaincluded only two chromosome numbers, 2n= 18 and 34, the three species ofDamrongiawere uniform with 2n= 18, while species belonging to the extendedPrimulinashowed only one basic number,x= 18, with 15 samples being diploid, and one being tetraploid. In the light of recent phylogenetic studies, polyploid as well as dysploid changes appear to have shaped the genomes of the newly defined generaHenckelia,Microchiritaand, to a lesser degree,Primulina.


Zootaxa ◽  
2007 ◽  
Vol 1617 (1) ◽  
pp. 67-68
Author(s):  
RICHARD S. ZACK ◽  
AUBREY MOORE ◽  
ROSS H. MILLER

Pygmy backswimmers, pleids, can be common in aquatic habitats with stagnant or slow-moving water that is rich in vegetation.  They are small bugs, usually less than 3.5 mm in length and confine themselves to the vegetation in which they hide and where they prey on mosquito larvae and other small arthropods (Schuh and Slater 1995).  The family is represented by 37 species in three genera: Plea, confined to the Old World; Neoplea confined to the New World; and Paraplea, the largest and most widely distributed genus (Schuh and Slater 1995).


2014 ◽  
Vol 10 (3) ◽  
pp. 20131093 ◽  
Author(s):  
Michail Rovatsos ◽  
Martina Pokorná ◽  
Marie Altmanová ◽  
Lukáš Kratochvíl

Many poikilothermic vertebrate lineages, especially among amphibians and fishes, possess a rapid turnover of sex chromosomes, while in endotherms there is a notable stability of sex chromosomes. Reptiles in general exhibit variability in sex-determining systems; as typical poikilotherms, they might be expected to have a rapid turnover of sex chromosomes. However, molecular data which would enable the testing of the stability of sex chromosomes are lacking in most lineages. Here, we provide molecular evidence that sex chromosomes are highly conserved across iguanas, one of the most species-rich clade of reptiles. We demonstrate that members of the New World families Iguanidae, Tropiduridae, Leiocephalidae, Phrynosomatidae, Dactyloidae and Crotaphytidae, as well as of the family Opluridae which is restricted to Madagascar, all share homologous sex chromosomes. As our sampling represents the majority of the phylogenetic diversity of iguanas, the origin of iguana sex chromosomes can be traced back in history to the basal splitting of this group which occurred during the Cretaceous period. Iguanas thus show a stability of sex chromosomes comparable to mammals and birds and represent the group with the oldest sex chromosomes currently known among amniotic poikilothermic vertebrates.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Alessio Strazzulla ◽  
Salvatore Cocuzza ◽  
Marilia Rita Pinzone ◽  
Maria Concetta Postorino ◽  
Stefano Cosentino ◽  
...  

We present a review of current knowledge about mucosal leishmaniasis (ML). Although involvement of mucous membranes is classically admitted in New World leishmaniasis, particularly occurring in infection byLeishmania (L.) braziliensisspecies complex, ML is also a possible presentation of Old World leishmaniasis, in eitherL. donovaniorL. majorspecies complex infections. Thus, ML has to be considered not only as a Latin American disease but as an Old and New World disease. We describe ML epidemiology, pathogenesis, clinics, diagnosis, and therapy. Considering both its highly disfiguring lesions and its possible lethal outcome, ML should not be underestimated by physicians. Moreover, leishmaniasis is expected to increase its burden in many countries as sandfly vector distribution is widespreading towards non-endemic areas. Finally, the lack of clear understanding of ML pathogenesis and the absence of effective human vaccines strongly claim for more research.


1966 ◽  
Vol 44 (3) ◽  
pp. 309-319 ◽  
Author(s):  
Gerald A. Mulligan

Chromosome numbers are given for a number of North American species in the genera Draba, Erophila, and Erysimum. New basic chromosome numbers are suggested for North American species of Draba and Erysimum and it is suggested that Erysimum inconspicuum reproduces by agamospermy.


2020 ◽  
Vol 69 (1) ◽  
pp. 13-19 ◽  
Author(s):  
Shubhi Rastogi ◽  
Deepak Ohri

AbstractThe present report is based on a cytological data base on 614 (56.0 %) of the total 1104 recognized species and 82 (90.0 %) of the 88 recognized genera of gymnosperms. Family Cycadaceae and many genera of Zamiaceae show intrageneric uniformity of somatic numbers, the genus Zamia is represented by a range of number from 2n=16-28. Ginkgo, Welwitschia and Gentum show 2n=24, 2n=42, and 2n=44 respectively. Ephedra shows a range of polyploidy from 2x-8x based on n=7. The family Pinaceae as a whole shows 2n=24except for Pseudolarix and Pseudotsuga with 2n=44 and 2n=26 respectively. Araucariaceae constantly shows 2n=26 while Podocarpaceae has a range of 2n=18-38. Sciadopityaceae and Cupressaceae are represented by 2n=20 and 2n=22 respectively. Taxaceae shows variable numbers of 2n=24, 36 and 22. Polyploidy is exceptional being represented by 8.0 % of the taxa studied. B-chromosomes have been studied in 31 taxa while heteromorphic sex chromosomes have been reported in some dioecious taxa.


2004 ◽  
Vol 52 (1) ◽  
pp. 13 ◽  
Author(s):  
Khidir W. Hilu

The wide range in basic chromosome number (x = 2–18) and prevalence of polyploidy and hybridisation have resulted in contrasting views on chromosomal evolution in Poaceae. This study uses information on grass chromosome number and a consensus phylogeny to determine patterns of chromosomal evolution in the family. A chromosomal parsimony hypothesis is proposed that underscores (1) the evolution of the Joinvilleaceae/Ecdeiocoleaceae/Poaceae lineage from Restionaceae ancestors with x = 9, (2) aneuploid origin of x�=�11 in Ecdeiocoleaceae and Poaceae (Streptochaeta, Anomochlooideae), (3) reduction to x = 9, followed by chromosome doubling within Anomochlooideae to generate the x = 18 in Anomochloa, and (4) aneuploid increase from the ancestral x = 11 to x = 12 in Pharoideae and Puelioideae, and further diversification in remaining taxa (Fig. 3b). Higher basic chromosome numbers are maintained in basal taxa of all grass subfamilies, whereas smaller numbers are found in terminal species. This finding refutes the 'secondary polyploidy hypothesis', but partially supports the 'reduction hypothesis' previously proposed for chromosomal evolution in the Poaceae.


Zootaxa ◽  
2020 ◽  
Vol 4869 (1) ◽  
pp. 149-150
Author(s):  
KAROL SZAWARYN ◽  
WIOLETTA TOMASZEWSKA

Recently the classification of the ladybird beetles’ tribe Epilachnini was revised based on morphological and molecular data (Szawaryn et al. 2015, Tomaszewska & Szawaryn 2016). Based on these findings a new classification of the tribe was proposed. The genus Epilachna Chevrolat in Dejean, 1837 sensu lato was split into several clades, with Epilachna sensu stricto limited to New World fauna, and one of the Afrotropical clades, formerly defined as Epilachna sahlbergi-group (Fürsch 1963), has been named Chazeauiana Tomaszewska & Szawaryn, 2015 (Szawaryn et al. 2015), with Epilachna sahlbergi Mulsant, 1850 as the type species. However, that taxon received an unnecessary replacement name, as Mulsant (1850) already described a subgenus of Epilachna named Cleta distributed in Afrotropics, with Epilachna eckloni Mulsant, 1850 as the type species, which also belongs to the E. sahlbergi-group. Consequently Cleta has been elevated to the genus level (Tomaszewska & Szawaryn 2016) and Chazeuiana was synonymized with Cleta as a junior synonym. Nonetheless, authors (Tomaszewska & Szawaryn 2016) were not aware that the name Cleta is preoccupied. It appeared that Duponchel (1845) established the genus Cleta in the family Geometridae (Lepidoptera) that makes Cleta Mulsant (1850) a junior homonym. Therefore, we propose here Afrocleta nom. nov. as a replacement name for Cleta Mulsant, 1850. 


2008 ◽  
Vol 54 (2) ◽  
pp. 223-238 ◽  
Author(s):  
Henrik Glenner ◽  
Philip Francis Thomsen ◽  
Alexey V. Rybakov ◽  
Bella S. Galil ◽  
Jens T. Hoeg

Within parasitic barnacles of the family Sacculinidae, the genus Heterosaccus is the third largest, with 12 species infesting various brachyuran hosts throughout the world. As part of an effort to reconstruct rhizocephalan phylogeny we performed an analysis of four species of Heterosaccus and of selected sacculinid and non-sacculinid rhizocephalans. We used both molecular sequence data (16s rDNA and 18s rDNA) and morphological characters from an SEM analysis of the cypris larvae. Using Bayesian methods we obtained a highly supported tree in which the four species of Heterosaccus form a monophylum, whereas both the genus Sacculina and the family Sacculinidae are polyphyletic. The sistergroup to Heterosaccus is a clade consisting of the sacculinids Loxothylacus panopaei and the "classical" rhizocephalan Sacculina carcini. The molecular results found support in cypris morphology, where we identified two distinct synapomorphies for Heterosaccus, both present in male cyprids only: A large flap extending posteriorly from the third antennular segment, and the male-specific aesthetasc on the third segment being reduced to a rudiment or lacking completely. Female cyprids didn't show generic level apomorphies but resembled those of other sacculinid species. No morphological synapomorphies were identified between Heterosaccus, L. panopaei and S. carcini. While larval characters proved to be informative, we conclude that future studies on rhizocephalan taxonomy must rely primarily on molecular data, both to provide an overall phylogenetic framework and to assure an accurate identification of species for biogeographical and other biological purposes.


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