scholarly journals Cytogeography and morphological characterisation of a taxonomic, polyploid complex of Mimosa (Leguminosae) from subtropical South America

2018 ◽  
Vol 31 (2) ◽  
pp. 190 ◽  
Author(s):  
M. Morales ◽  
M. Fradkin ◽  
C. Bessega ◽  
L. Poggio ◽  
R. H. Fortunato

Mimosa subseries Dolentes Barneby and Brevipedes Barneby are ecologically and morphologically high-diversified infrageneric taxa of this genus in southern South America. We performed a cytogenetical and morphological analysis of both subseries. Chromosome numbers from accessions throughout the area of distribution were studied. The chromosome numbers 2n=8x=104 for M. dolens subsp. callosa (Benth.) Barneby, M. dolens subsp. acerba varieties acerba (Benth.) Barneby, latifolia (Benth.) Barneby and rudis (Benth.) Barneby, M. dolens subsp. rigida var. rigescens (Benth.) Barneby, var. anisitsii (Lindm.) Barneby and var. foliolosa (Benth.) Barneby; and 2n=4x=52 for M. sceptrum Barneby, M. aff. custodis Barneby and M. dolens var. pangloea Barneby are presented for the first time. Their karyotypes were symmetric, with small chromosomes. There were several areas with taxa growing in sympatry, occasionally with intermediate forms. No diploids were found, which suggests the presence of either a declining polyploid complex or ancient polyploidy in the clade of southernmost representatives of M. series Mimosa, the most derived of the genus. Some vegetative, inflorescence and carpological characters seem to be associated with chromosome duplication. The distribution pattern of the cytotypes suggests events of chromosome duplication in centres of diversity and expansion of octoploids to the southernmost areas of distribution. Our findings support the importance of polyploidy in the morphological diversity, distribution and speciation of this complex.

2010 ◽  
Vol 42 (6) ◽  
pp. 727-737 ◽  
Author(s):  
David J. GALLOWAY

AbstractAspiciliopsis macrophthalma, Placopsis fusciduloides, P. gelidioides and P. tararuana are reported for the first time from southern South America. New records for 13 species of Placopsis in southern South America are reported, and a revised key to 22 species of Placopsis and A. macrophthalma in the region is given.


Zootaxa ◽  
2017 ◽  
Vol 4338 (2) ◽  
pp. 263 ◽  
Author(s):  
CRISTIAN J. GRISMADO ◽  
NICOLÁS LÓPEZ CARRIÓN

A new genus of gnaphosid spiders, Almafuerte, gen. nov., is described for seven species from Southern South America. The new genus is diagnosed by a conspicuous retrolateral tegular projection on the male palp, and by having three teeth on the cheliceral retromargin. It comprises six species from Argentina, A. peripampasica sp. nov. (type species), from Central Argentina, also present in Uruguay, A. kuru sp. nov., from Santiago del Estero, A. vigorosa sp. nov., from Corrientes, A. goloboffi sp. nov., from Salta and Jujuy, A. remota sp. nov., from Santiago del Estero and Mendoza, and A. giaii (Gerschman & Schiapelli) comb. nov., here transferred from Echemus, from Santa Fe (the female is here described by the first time); and one species from Bolivia, A. facon sp. nov., from Cochabamba. Hypotheses of relationships of the new taxa are briefly discussed, in the context of the previously proposed groupings: the subfamilies Echeminae and Drassodinae (sensu Platnick 1990) and the “Echemus group” (sensu Murphy 2007). 


Phytotaxa ◽  
2018 ◽  
Vol 362 (2) ◽  
pp. 115
Author(s):  
DANILO MARQUES ◽  
GABRIELA ELIZABETH FARCO ◽  
JIMI NAOKI NAKAJIMA ◽  
MASSIMILIANO DEMATTEIS

A morphological analysis of the genus Lepidaploa (Vernonieae) of southern South America has been carried out. Until now, the information concerning the genus was fragmented and incomplete for this region. Altogether, 13 species are described and illustrated here. A comprehensive key to the species of southern South America is presented; in addition, we characterized and delimited the distributions of the species.


2021 ◽  
Vol 157 (3) ◽  
pp. 153-167
Author(s):  
Michael S. Engel ◽  
Diego A. Guevara ◽  
Rodulfo Ospina-Torres ◽  
Victor H. Gonzalez

The diverse bee genus Psaenythia Gerstaecker (Panurginae, Protandrenini), hitherto known from central and southern South America, is recorded from northern South America for the first time. Two new species are described: Psaenythia diceratops, sp. n., from northeastern Colombia, and P. guaricoensis, sp. n., from central Venezuela. The males of P. diceratops are noteworthy for possessing prominent apicolateral clypeal horns, elongate scythe-like mandibles, and displaying macrocephaly with strong dimorphism. Keywords: Andrenidae, Anthophila, Apoidea, Panurginae, taxonomy, Neotropical


Zootaxa ◽  
2017 ◽  
Vol 4337 (4) ◽  
pp. 523
Author(s):  
CHRISTIAN R. GONZÁLEZ

The tabanid tribe Diachlorini (Diptera) is the most genus-rich tribe in the Tabanidae; the tribe is cosmopolitan, but the greatest species richness and morphological diversity are found in the Australasian and Neotropical Regions. A new arrangement for the species of Acellomyia González is given; Acellomyia lauta (Hine) is transferred to a new genus, Montismyia gen.n., based on its morphological differences from Acellomyia and geographical distribution. The morphological differences between Acellomyia and Montismyia gen. n. are discussed. Two new species, Acellomyia casablanca sp.n. and Acellomyia puyehue sp.n., are described from specimens collected in southern Chile. Comparison of the morphology of Acellomyia paulseni mapuche (Coscarón & Philip) stat.nov. indicate that they should be elevated to species rank. A key to species of Acellomyia is provided and diagnostic characters are illustrated. 


Author(s):  
Pedro PIÑERO ◽  
A. Itatí OLIVARES ◽  
Diego H. VERZI ◽  
Victor H. CONTRERAS

ABSTRACT Echimyidae is the most widely diversified family among hystricognath rodents, both in the number of species and variety of lifestyles. In the Patagonian Subregion of southern South America, extinct echimyids related to living arboreal species (Echimyini) are recorded up to the middle Miocene, whereas all the known southern fossils since the late Miocene are linked to terrestrial and fossorial lineages currently inhabiting the Chacoan open biome in eastern South America. In this work, we describe a new genus of echimyid rodent, Paralonchothrix gen. nov., from the late Miocene of northwestern Argentina and western Brazil. Its single recognised species, Paralonchothrix ponderosus comb. nov., is represented by two hemimandibles. One of them comes from a level of Loma de Las Tapias Formation, underlying a tuff dated at 7.0 ± 0.9 Ma (Huayquerian age, late Miocene); the other specimen comes from the ‘Araucanense’ of Valle de Santa María (type locality, Huayquerian age, late Miocene). A phylogenetic analysis linked Paralonchothrix to Lonchothrix, both being the sister group to Mesomys. Thereby, for the first time, an echimyid linked to living Amazonian arboreal clades is recognised for the late Miocene of southern South America. Paralonchothrix gen. nov. thus represents an exceptional record that raises the need to review the postulated evolutionary pattern for echimyids recorded at high latitudes since the late Miocene. The new genus provides a minimum age (ca.7 Ma) in the fossil record for the divergence between Mesomys and Lonchothrix. The palaeoenvironmental conditions inferred for the late Miocene in western and northwestern Argentina suggest savanna-type environments, with areas with more closed woodlands in peri-Andean valleys. The record of Paralonchothrix gen. nov. supports the hypothesis that this area would have maintained connections with tropical biomes of northern South America during the late Miocene.


Zootaxa ◽  
2017 ◽  
Vol 4216 (3) ◽  
pp. 261 ◽  
Author(s):  
MIGUEL SIMÓ ◽  
ARNO A. LISE ◽  
GABRIEL POMPOZZI ◽  
ÁLVARO LABORDA

Three species of the genus Allocosa Banks, 1900 from southern South America are redescribed: Allocosa alticeps (Mello-Leitão, 1944), A. brasiliensis (Petrunkevitch, 1910) and A. senex (Mello-Leitão, 1945). The female of A. senex is described for the first time and the species is revalidated. A new species, A. marindia sp. nov. from southern Uruguay and southern Brazil is described. The new species is distinguished by the flattened terminal apophysis of the male bulb and the conspicuous pointed projections on the posterior margin of the female epigynum. The species inhabits in sandy estuarine and oceanic coasts with psammophile vegetation. 


Phytotaxa ◽  
2018 ◽  
Vol 357 (3) ◽  
pp. 179
Author(s):  
ADRIÁN O. CEFARELLI ◽  
MARTINA MASCIONI ◽  
JULIÁN SIMONATO ◽  
GASTÓN O. ALMANDOZ ◽  
MARIA VERNET

A new variety of the marine diatom Haslea crucigeroides, H. crucigeroides var. australis, var. nov., is described here based on phytoplankton samples collected in sub-Antarctic coastal waters of the southern South America and Antarctica. The new taxon was characterized by using light and electron microscopy, and the holotype of H. crucigeroides, the only existing material type, was analyzed with light microscopy. Haslea crucigeroides var. australis differs from the nominal variety by having acute valve apices instead of acute rostrate; furthermore, it has a different geographical distribution. The species is being recorded in the Southern Hemisphere for the first time. Cell abundance and a brief discussion on the species habitat are also presented.


1976 ◽  
Vol 25 (1) ◽  
pp. 113-130 ◽  
Author(s):  
Plínio Solhes Moreira

This paper reports on part of the species of the marine isopod genus Serolis (Crustacea, Flabellifera, Serolidae) collected from benthic stations performed during one of the cruises of the Brazil ian Navy Oc/S "Almirante Saldanha" along southern South America. The species reported are Serolis polccris Richardson, 1911, Serolis elliptica Sheppard, 1933, Serolis uaperta Moreira, 1971, and Serolis foresti Bastida & Torti, 1970. A complete synonymy is given for each of these species, as well as the main distinctive characteristics enabling its ready recognition. Some remarks are provided on features not lengthned treated on previous accounts. The geographi cal distribution of all named taxa is given. Serolis uaperta is for the first time reported from off State of Rio Grande do Sul (Brazil) and Uruguay, extending considerably southernwards its southern limit of distribution. Both Serolis foresti and Serolis elliptica are also for the first time recorded from off Uruguay.


Zootaxa ◽  
2017 ◽  
Vol 4338 (1) ◽  
pp. 51 ◽  
Author(s):  
DAMIÁN E. PÉREZ ◽  
CLAUDIA J. DEL RÍO

The systematics of the Family Carditidae is currently poorly elucidated. This paper reviews the Eocene to Pleistocene carditids from Patagonia and Entre Ríos Province (Argentina). Twelve species are described and illustrated and the presence of the genera Cyclocardia Conrad, Pleuromeris Conrad, Scalaricardita Sacco, Fasciculicardia Maxwell and Purpurocardia Maxwell in southern South America is discussed. The genus Scalaricardita is documented for the first time in South America. Two new genera, Darwinicardia gen. nov. and Kolmeris n. gen. are proposed for the species ‘Venericardia’ patagonica (Sowerby) and ‘V.’ tehuelchana (Ihering), respectively, and one new species, Cyclocardia dalek sp. nov., is described. 


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