Diploidy, polyploidy, and agamospermy among species of Eupatorium (Compositae)

1976 ◽  
Vol 54 (24) ◽  
pp. 2907-2917 ◽  
Author(s):  
Victoria I. Sullivan
Keyword(s):  
Normal Embryo ◽  
Herbarium Specimens ◽  
Pollen Production ◽  
Chromosome Counts ◽  
Distribution Maps ◽  
Normal Pollen ◽  
Abortive Pollen ◽  
Chromosomal Pairing ◽  
First Time

Diploids of eight species of Eupatorium, triploids of three species, and tetraploids of four species are reported here for the first time. Meiosisin microsporocytes of triploids and tetraploids either failed to occur resulting in failure of pollen production or less frequently resulted in either incomplete chromosomal pairing or complete asynapsis; the latter two events lead to the production of grossly malformed, abortive pollen with unevenly deposited walls. Megasporogenesis examined in two polyploid plants led to the formation of eight-nucleate, unreduced embryo sacs which formed endosperm and embryos without pollination, indicating that the sporophytes develop asexually through agamospermy. Evidence is given that this may be a facultative characteristic. Megasporogenesis, studied in diploids of four species, produced normal embryo sacs with no indication of agamospermous development. Diploid plants of 11 of 12 species were tested and found to be self-incompatible.Since diploids could readily be distinguished from polyploids by pollen production (diploids produced normal pollen, polyploids produced none or malformed pollen), distributions of a large number of diploid, triploid, and tetraploid individuals could be determined from examining anthers of herbarium specimens. Distribution maps were made using these data as well as those from chromosome counts. Diploid members of species having both diploid, triploid, and (or) tetraploid members consistently had smaller distributional ranges than polyploids of the same species.

scholarly journals A Synopsis of Orthotrichum s. lato (Bryophyta, Orthotrichaceae) in China, with Distribution Maps and a Key to Determination

Plants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 499
Author(s):  
Vítězslav Plášek ◽  
Zuzana Komínková ◽  
Ryszard Ochyra ◽  
Lucie Fialová ◽  
Shuiliang Guo ◽  
...  
Keyword(s):  
Single Species ◽  
Herbarium Specimens ◽  
Distribution Maps ◽  
First Time

A total of 46 species and two varieties of the traditionally interpreted genus Orthotrichum are currently known to occur in China. They represent five genera, including Orthotrichum (29 species), Lewinskya (14 species and two varieties), and Nyholmiella and Leratia that are represented by a single species each. The fifth genus Florschuetziella, also consisting of only one species, F. scaberrima, is an entirely neglected representative of the China’s moss flora. A list of all accepted taxa is presented and for each taxon all literature records and herbarium specimens are enumerated for provinces in which they have been recorded, and their distribution is mapped. A key to determination of Chinese orthotrichalean mosses is presented. A chronological list of 63 species and varieties and two designations, O. catagonioides and O. microsporum which have never been validly published, reported from China in the years 1892–2020 is presented. Four species, Orthotrichum brasii, O. hooglandii, O. elegans and O. gymnostomum are excluded from the bryoflora of China and Lewinskya affinis var. bohemica and Orthotrichum schimperi are recorded for the first time from this country. Phytogeography of the Chinese taxa of the orthotrichalean mosses is considered and they are grouped into eight phytogeographical elements and five sub-elements.

Can morphology and chromosome number contribute to species delimitation? A case in the Hibiscus trionum complex (Tribe Hibisceae, Malvaceae)

Phytotaxa ◽  
2019 ◽  
Vol 416 (4) ◽  
pp. 278-286
Author(s):  
MOHAMED OWIS BADRY ◽  
JENNIFER A. TATE ◽  
PRASHANT JOSHI ◽  
AHMED MAHMOUD ABBAS ◽  
SOHAIR THABET HAMED ◽  
...  
Keyword(s):  
Chromosome Number ◽  
Species Delimitation ◽  
Taxonomic Revision ◽  
Herbarium Specimens ◽  
Chromosome Counts ◽  
Comprehensive Description ◽  
Hibiscus Trionum ◽  
The World ◽  
First Time

A taxonomic revision of Hibiscus trionum from Egypt was undertaken using morphological and cytological studies of field collections and herbarium specimens. The data indicate that all specimens so far collected in Egypt belong to H. tridactylites, rather than H. trionum. This paper includes a comprehensive description of H. tridactylites, its occurrence, a comparison with other species in the H. trionum complex, and comments on habitat, along with images for easy identification. In addition, chromosome counts for this species from Egypt have been determined for the first time, which add to existing information on chromosome counts for the species from different regions of the world.

A revision of Centaurea sect. Cynaroides (Asteraceae, Cardueae—Centaureinae)

Phytotaxa ◽  
2018 ◽  
Vol 363 (1) ◽  
pp. 1 ◽  
Author(s):  
KAZEM NEGARESH ◽  
MOHAMMAD REZA RAHIMINEJAD
Keyword(s):  
Natural Habitat ◽  
Taxonomic Status ◽  
Herbarium Specimens ◽  
Chromosome Counts ◽  
Type Specimens ◽  
Distribution Maps ◽  
Biogeographical Distribution ◽  
Distribution And Ecology ◽  
Three New Species ◽  
Close Relatives

The taxonomic status of the taxa known to belong to Centaurea sect. Cynaroides and its close relatives was revised on the basis of herbarium specimens from the authors’ expeditions and other collections. It is established that Boissier is the correct author for C. sect. Cynaroides, and C. regia is designated as a lectotype of this section. Thirty seven species are recognised in the section. Three new species (C. kamalnejadii, C. mozaffarianii, and C. zarrei), four new subspecies (C. amadanensis subsp. ranjbarii, C. cataonica subsp. syriaca, C. gigantea subsp. rechingeri, and C. kurdica subsp. ciliata) and two varieties (C. regia var. longispinosa and C. regia var. purpurea) are described. Two subspecies are reduced to the variety rank, and two varieties are elevated to the subspecies rank. Centaurea sect. Paraphysis is reduced as a synonym of C. sect. Cynaroides. Centaurea onopordifolia is transferred from C. sect. Cynaroides to a new section, i.e. C. sect. Cardueae. Three lectotypes are designated, six lectotypes from previous lectotypifications are rejected and the author names for six species are corrected. The recognized taxa, the relevant synonyms, type details, examined specimen lists, full descriptions and a taxonomic key are provided for this section. Distribution maps are provided for each sections, species, subspecies and varieties. Images of the type specimens of all taxa and also photos of the species in its natural habitat and related fields are provided. Five chromosome counts (2n = 18) are reported for C. amadanensis subsp. amadanensis, C. amadanensis subsp. gymnoclada, C. nemecii, C. regia var. regia, and C. regia var. purpurea. Biogeographical distribution and ecology of taxa of C. sect. Cynaroides are presented and discussed. In addition, cytotaxonomy, homoploidy and evolution of C. sect. Cynaroides are illustrated and discussed. Finally, the pollination of C. sect. Cynaroides is illustrated, and also images of the pollinators of some species of the section are provided.

scholarly journals An integrative monograph of Carex section Schoenoxiphium (Cyperaceae)

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11336
Author(s):  
Modesto Luceño ◽  
Tamara Villaverde ◽  
José Ignacio Márquez-Corro ◽  
Rogelio Sánchez-Villegas ◽  
Enrique Maguilla ◽  
...  
Keyword(s):  
Plastid Dna ◽  
Eastern Africa ◽  
Herbarium Specimens ◽  
Distribution Maps ◽  
Distinct Genus ◽  
Biogeographic Region ◽  
Center Of Diversity ◽  
History Of ◽  
Nomen Novum ◽  
First Time

Carex section Schoenoxiphium (Cariceae, Cyperaceae) is endemic to the Afrotropical biogeographic region and is mainly distributed in southern and eastern Africa, with its center of diversity in eastern South Africa. The taxon was formerly recognized as a distinct genus and has a long history of taxonomic controversy. It has also an important morphological and molecular background in particular dealing with the complexity of its inflorescence and the phylogenetic relationships of its species. We here present a fully updated and integrative monograph of Carex section Schoenoxiphium based on morphological, molecular and cytogenetic data. A total of 1,017 herbarium specimens were examined and the majority of the species were studied in the field. Previous molecular phylogenies based on Sanger-sequencing of four nuclear and plastid DNA regions and RAD-seq were expanded. For the first time, chromosome numbers were obtained, with cytogenetic counts on 44 populations from 15 species and one hybrid. Our taxonomic treatment recognizes 21 species, one of them herein newly described (C. gordon-grayae). Our results agree with previous molecular works that have found five main lineages in Schoenoxiphium. We provide detailed morphological descriptions, distribution maps and analytical drawings of all accepted species in section Schoenoxiphium, an identification key, and a thorough nomenclatural survey including 19 new typifications and one nomen novum.

A Taxonomic Treatment of Rogiera (Guettardeae, Rubiaceae)

2021 ◽  
Vol 46 (1) ◽  
pp. 186-210
Author(s):  
Alejandro Torres-Montúfar ◽  
Hilda Flores-Olvera ◽  
Helga Ochoterena
Keyword(s):  
Taxonomic Revision ◽  
Morphological Evidence ◽  
Herbarium Specimens ◽  
Phenological Data ◽  
Distribution Maps ◽  
Taxonomic Treatment ◽  
Center Of Diversity ◽  
Previously Treated ◽  
Northern South America ◽  
First Time

Abstract—Rogiera (Guettardeae, Rubiaceae) is a Neotropical genus distributed from Mexico to northern South America that includes shrubs, treelets, or trees, which were previously treated in the taxonomically controversial and confused Rondeletia complex. Rogiera can be recognized among other Rubiaceae by the combination of multiflowered inflorescences, heterostylous flowers, quincuncial corolla aestivation, a hairy ring at the corolla mouth, and capsular fruits with loculicidal dehiscence. Despite the recent taxonomic circumscription of Rogiera there is not a comprehensive taxonomic treatment to it. Moreover, regional floristic treatments disagree on the species circumscriptions, with discrepancies in the number of species of Rogiera from 11 to 20. Based on molecular and morphological evidence studied on field and herbarium specimens, we present a taxonomic revision of Rogiera. We recognize ten species; Mexico is the center of diversity with nine species, four of them endemic. An identification key, descriptions, distribution maps, nomenclatural history, phenological data, and illustrations of all the species in the genus are provided for the first time. Several names required lecto- or epitypifications designated here.

scholarly journals A taxonomic revision of the African genus Desplatsia Bocq. (Malvaceae – Grewioideae)

2019 ◽  
Author(s):  
Julia Wellsow ◽  
Michelle Hart ◽  
Peter Wilkie ◽  
David J. Harris
Keyword(s):  
Conservation Status ◽  
Central Africa ◽  
Taxonomic Revision ◽  
Herbarium Specimens ◽  
Distribution Maps ◽  
West And Central Africa ◽  
Species Descriptions ◽  
First Time ◽  
Trees And Shrubs ◽  
African Genus

A taxonomic revision of Desplatsia Bocq. (Malvaceae s. lat. Juss., subfamily Grewioideae Hochr., tribe Grewieae Endl.) based on about 800 herbarium specimens is presented. Desplatsia is a genus of trees and shrubs found in tropical West and Central Africa and is characterized by subulately divided stipules, the absence of an androgynophore, stamens that are fused to a tube at the base, and large and distinctive fruits that are dispersed by elephants. Four species are recognized (D. subericarpa Bocq., D. chrysochlamys (Mildbr. & Burret) Mildbr. & Burret, D. dewevrei (De Wild. & T.Durand) Burret and D. mildbraedii Burret) and 12 species names are placed into synonymy, two of which have been put into synonymy for the first time: D. floribunda Burret syn. nov. and D. trillesiana (Pierre ex De Wild.) Pierre ex A.Chev. syn. nov. All four species are widely distributed and their conservation status is assessed as Least Concern (LC). A key to the species, full species descriptions, illustrations, a specimen citation list and distribution maps are provided.

CYTOTAXONOMY OF THREE SPECIES OF CENTAUREA ADVENTIVE IN CANADA

1954 ◽  
Vol 32 (1) ◽  
pp. 182-186 ◽  
Author(s):  
R. J. Moore ◽  
C. Frankton
Keyword(s):  
Chromosome Number ◽  
Introduced Species ◽  
Chromosome Numbers ◽  
Diploid Chromosome Number ◽  
Chromosome Counts ◽  
Normal Pollen ◽  
Taxonomic Problem ◽  
First Time

The chromosome numbers of three introduced species of Centaurea are here reported: C. diffusa Lam., 2n = 18; C. maculosa, Lam., 2n = 36; C. repens L., 2n = 26. The chromosome counts of C. diffusa and of C. maculosa, which are here reported for the first time, help to clarify a taxonomic problem. A pappus is usually lacking on the achenes of C. diffusa but is present on those of C. maculosa. As a result, plants of C. diffusa with a short pappus have been considered to be possible hybrids between these species. Three such plants here studied had the diploid chromosome number 18, rather than the triploid number to be expected in such a hybrid. Examination of pollen of suspected hybrid specimens shows that the percentage of normal pollen is high. This fact also supports the belief that plants of C. diffusa with a short pappus on the achene are not hybrids with C. maculosa.

scholarly journals A revision of Scleria (Cyperaceae) in Madagascar

2019 ◽  
Vol 64 (3) ◽  
pp. 195-213 ◽  
Author(s):  
J. Galán Diaz ◽  
K. Bauters ◽  
L. Rabarivola ◽  
M. Xanthos ◽  
P. Goetghebeur ◽  
...  
Keyword(s):  
Endemic Species ◽  
Habitat Preference ◽  
Taxonomic Revision ◽  
Species Level ◽  
Herbarium Specimens ◽  
Distribution Maps ◽  
Conservation Assessments ◽  
Data Deficient ◽  
Rare Endemic ◽  
First Time

A taxonomic revision of the genus Scleria (Cyperoideae, Cyperaceae) in Madagascar is presented. Herbarium specimens have been examined and 422 identified to species level. Our results recognise 25 species of Scleria from Madagascar, plus an additional heterotypic variety. Eight species are endemic to Madagascar, two are near endemic, eight taxa are also found on mainland Africa, and eight are widespread tropical taxa. Scleria achtenii is reported from Madagascar for the first time, and S. rosea is accepted at species level instead of being considered as a synonym of S. trialata. Distribution maps, conservation assessments, and notes on synonymy, ecology and ethnobotany are provided. Fourty-seven names are typified. Three rare endemic species: S. andringitrensis, S. madagascariensis and S. perpusilla, are assessed as threatened; and a recently described species, S. ankaratrensis, is indicated as Data Deficient. The most species-rich infrageneric taxa, sections Hypoporum, Abortivae and Foveolidia include 18 taxa in total, and showed strong differences in habitat preference.

The revision of lichens, lichenicolous and non-lichenized fungi from the Vodlozersky National Park (Republic of Karelia, Russia) in the Herbarium of the Botanical Museum, University of Helsinki

2019 ◽  
Vol 53 (2) ◽  
pp. 337-348
Author(s):  
V. N. Tarasova ◽  
T. Ahti ◽  
O. Vitikainen ◽  
A. V. Sonina ◽  
L. Myllys
Keyword(s):  
National Park ◽  
Common Species ◽  
Lichenized Fungi ◽  
Herbarium Specimens ◽  
Lichenicolous Fungi ◽  
Biogeographic Province ◽  
Botanical Museum ◽  
The Republic ◽  
First Time ◽  
Lichen Flora

This is a report of a revision of 565 herbarium specimens of lichens, lichenicolous or non-lichenized fungi and additional locality records of common species produced from a visit of the Russian-Finnish expedition to Vodlozersky National Park right after its foundation in 1991. The analyzed collection and field records represent the earliest information about the lichen flora of the territory of the park. In total, 177 species are listed including 173 lichens, 3 non-lichenized and 1 lichenicolous fungi. Xylographa rubescens is new to the Republic of Karelia. Twenty two species are reported for the first time for biogeographic province Karelia transonegensis; 47 species for the Karelian part of Vodlozersky National Park; and 17 species for the whole territory of the park.

scholarly journals The genera Turnera and Piriqueta (Passifloraceae sensu lato) in the state of Pernambuco, Brazil

Rodriguésia ◽  
2019 ◽  
Vol 70 ◽  
Author(s):  
Andréia Zelenski ◽  
Rafael Louzada
Keyword(s):  
Species Richness ◽  
Atlantic Forest ◽  
New Record ◽  
National Park ◽  
The State ◽  
Northeastern Brazil ◽  
Distribution Maps ◽  
Taxonomic Treatment ◽  
Semideciduous Seasonal Forest ◽  
First Time

Abstract A taxonomic treatment of the genera Turnera and Piriqueta in the state of Pernambuco, northeastern Brazil, is presented. Fourteen species of Turnera and six species of Piriqueta were found in the Atlantic Forest and Caatinga, of which nine are endemic to Brazil. Turnera pernambucensis is threatened and restricted to the Atlantic Forest of Pernambuco, while T. joelii is a new record for the state. The species predominate in steppe savanna and semideciduous seasonal forest, but several of them grow naturally in anthropized areas. Catimbau National Park is the locality with the highest species richness. Tristyly is recorded for the first time in Piriqueta guianensis. Identification keys, descriptions, illustrations, distribution maps, and comments about habitat, flowering, fruiting, and morphological relationships are provided.

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