María Cristina Tellería

The Subfamily Mutisioideae (Asteraceae)

The subfamily Mutisioideae (74 genera, ca. 865 species), which comprises three tribes, Mutisieae (43 genera, ca. 500 species), Nassauvieae (25 genera, ca. 315 species), and Stifftieae (six genera, 48 species), is analyzed at the generic level. A total of 87 genera traditionally related to Mutisioideae were studied. The genera of Mutisioideae are described and illustrated, and keys to tribes and genera are given. Corollas, anthers, styles, and pollen, are analyzed and discussed. The styles (smooth, rugulose to papillose, papillae short and rounded) constitute the main characters for delimiting the subfamily. The presence and distribution of the style papillae support the recognition of three tribes, although other characters as corolla shape contribute to their definition. The pollen of Nassauvieae can be clearly differentiated from the pollen of Mutisieae and Stifftieae. The morphology supports the exclusion of Brachylaena, Cloiselia, Dicoma, Duseniella, Erythrocephalum, Gladiopappus, Hesperomannia, Macledium, Moquinia, Pasaccardoa, Pleiotaxis, Tarchonanthus, and Warionia but not the exclusion of other taxa, for example, Hecastocleis, the Gochnatia complex, or the Ainsliaea group members.ResumenLa subfamilia Mutisioideae (74 géneros, ca. 865 especies), que comprende tres tribus, Mutisieae (43 géneros, ca. 500 especies), Nassauvieae (25 géneros, ca. 315 especies), y Stifftieae (6 géneros, 48 especies), es analizada a nivel genérico. Se estudió un total de 87 géneros que tradicionalmente fueron relacionados a Mutisioideae. Se describen e ilustran los géneros de Mutisioideae, y se proveen claves para las tribus y los géneros. Se analizan y discuten las corolas, anteras y estilos. Los caracteres del estilo (glabro, ruguloso a papiloso, las papilas cortas y redondeadas) son los más importantes para delimitar la subfamilia. La presencia y distribución de las papilas del estilo ayudan al reconocimiento de las tres tribus, aunque otros caracteres como la forma de la corola contribuyen a su definición. El polen de Nassauvieae se puede diferenciar claramente del polen de Mutisieae y Stifftieae. La morfología apoya la exclusión de Brachylaena, Cloiselia, Dicoma, Duseniella, Erythrocephalum, Gladiopappus, Hesperomannia, Macledium, Moquinia, Pasaccardoa, Pleiotaxis, Tarchonanthus, y Warionia, pero no la exclusión de otros taxa, por ejemplo, Hecastocleis, los miembros del complejo Gochnatia o del grupo Ainsliaea.

Pollen collected by honey bees (Apis mellifera L.) from south of Caldén district (Argentina): botanical origin and protein content

In the south of the Caldén district (Phytogeographical province of Espinal, Argentina) the availability of flowering along with the botanical origin and protein content of pollen harvested by honey bees, was studied. During two apiculture periods (from end August to early January) pollen loads were collected every fortnight using pollen traps. A total of 637.96 g of pollen loads was analysed. From 139 species recorded, only 29 were visited by honey bees. In terms of biomass the contribution of exotic plants was high at the end of the winter (Brassicaceae and Erodium cicutarium); during this period of pollen shortage, honey bees collected spores of Puccinia interveniens. During the spring, the native plants (Condalia microphylla, Chuquiraga erinacea, Discaria americana, Grindelia tehuelches, Larrea divaricata, Prosopis sp., Prosopidastrum globosum and Vicia pampicola) were utilised. Those pollen types of high protein level were collected most intensively.

Early evolution of the angiosperm clade Asteraceae in the Cretaceous of Antarctica

Significance The flowering plant family Asteraceae (e.g. sunflowers, daisies, chrysanthemums), with about 23,000 species, is found almost everywhere in the world except in Antarctica. Asteraceae (or Compositae) are regarded as one of the most influential families in the diversification and evolution of a large number of animals that heavily depends on their inflorescences to survive (e.g. bees, hummingbirds, wasps). Here we report the discovery of pollen grains unambiguously assigned to Asteraceae that remained buried in Antarctic deposits for more than 65 million years along with other extinct groups (e.g. Dinosaurs, Ammonites). Our discovery drastically pushes back the assumed origin of Asteraceae, because these pollen grains are the oldest fossils ever found for the family. The Asteraceae (sunflowers and daisies) are the most diverse family of flowering plants. Despite their prominent role in extant terrestrial ecosystems, the early evolutionary history of this family remains poorly understood. Here we report the discovery of a number of fossil pollen grains preserved in dinosaur-bearing deposits from the Late Cretaceous of Antarctica that drastically pushes back the timing of assumed origin of the family. Reliably dated to ∼76–66 Mya, these specimens are about 20 million years older than previously known records for the Asteraceae. Using a phylogenetic approach, we interpreted these fossil specimens as members of an extinct early diverging clade of the family, associated with subfamily Barnadesioideae. Based on a molecular phylogenetic tree calibrated using fossils, including the ones reported here, we estimated that the most recent common ancestor of the family lived at least 80 Mya in Gondwana, well before the thermal and biogeographical isolation of Antarctica. Most of the early diverging lineages of the family originated in a narrow time interval after the K/P boundary, 60–50 Mya, coinciding with a pronounced climatic warming during the Late Paleocene and Early Eocene, and the scene of a dramatic rise in flowering plant diversity. Our age estimates reduce earlier discrepancies between the age of the fossil record and previous molecular estimates for the origin of the family, bearing important implications in the evolution of flowering plants in general.

Fossil pollen records indicate that Patagonian desertification was not solely a consequence of Andean uplift

The Patagonian steppe-a massive rain-shadow on the lee side of the southern Andes-is assumed to have evolved ~15-12 Myr as a consequence of the southern Andean uplift. However, fossil evidence supporting this assumption is limited. Here we quantitatively estimate climatic conditions and plant richness for the interval ~10-6 Myr based on the study and bioclimatic analysis of terrestrially derived spore-pollen assemblages preserved in well-constrained Patagonian marine deposits. Our analyses indicate a mesothermal climate, with mean temperatures of the coldest quarter between 11.4 °C and 16.9 °C (presently ~3.5 °C) and annual precipitation rarely below 661 mm (presently ~200 mm). Rarefied richness reveals a significantly more diverse flora during the late Miocene than today at the same latitude but comparable with that approximately 2,000 km further northeast at mid-latitudes on the Brazilian coast. We infer that the Patagonian desertification was not solely a consequence of the Andean uplift as previously insinuated.

A Comparative Palynologic Study of Chaetanthera (Asteraceae, Mutisieae) and Allied Genera

Abstract Chaetanthera is a South American genus of 43 species in seven subgenera. Pollen grain morphology of 39 species of Chaetanthera and allied genera of Mutisiinae was surveyed using light and electron microscopy. Two palynologic groups are distinguished in Chaetanthera, defined as types I and II, the latter with the subtypes II 1 and II 2. The groups are supported by additional morphological and habit characteristics. Type I has pollen with a thinner exine (usually 5–7 μm thick), subrectangular shape, nexine outline elliptic to subrectangular, and medium-sized; type II has pollen with a thicker exine (11–18 μm thick), elliptic shape, nexine outline dumbbell-shaped, and large-sized. Subtype II 1 has columellae in the ectosexine, whereas subtype II 2 has a compact ectosexine. A palynologic alliance is established among the mutisiean genera Aphyllocladus, Gypothamnium, and Plazia (Plazia group), species of Onoseris and Urmenetea (Onoseris group), Brachyclados, Chaetanthera, Lulia, Mutisia, and Pachylaena (Mutisia group), Gerbera, Trichocline, and Uechtritzia (part of the Gerbera group), and Hyaloseris and Dinoseris on the basis of pollen similarities. These generic groups are defined by the habit and floral and fruit features, and the pollen structure is mainly useful to establish relationships among the groups. In this scheme the Mutisia group, which includes Chaetanthera, approaches the Onoseris and Gerbera groups.

Proustia and Lophopappus (Asteraceae, Mutisieae): generic and subtribal relationships based on pollen morphology

Abstract Pollen of Proustia (10 specimens examined) and Lophopappus (12 specimens examined) (Asteraceae, Mutisieae) are described as part of an analysis of the classification of these genera. Their exine structure is determined and compared with structures found in other genera of Mutisieae (25 specimens examined and data of other authors), in order to clarify the subtribal position of Proustia and Lophopappus. Pollen of Proustia and Lophopappus have the following characters in common: Grains radially symmetrical and isopolar; tricolporate, long colpi with a microgranulate membrane, endoaperture lalongate with acute or bifurcate equatorial ends; subprolate or prolate-spheroidal; elliptic or spheroidal; polar caps conspicuous or not so distinctive, and exine microechinate. Two types of sexine structure are observed: (1) Trixis type, with two columellate ramified sublayers, the inner sublayer thicker than the outer one (found in Lophopappus berberidifolius, L. tarapacanus, Proustia cuneifolia var. cuneifolia, P. cuneifolia var. mendocina, P. cuneifolia var. mollis, P. ilicifolia var. baccharoides, and P. pyrifolia); and (2) Proustia type, with two equally thick sublayers of ramified columella (found in Lophopappus blakei, L. cuneatus, and L. foliosus). Proustia ilicifolia var. ilicifolia and Lophopappus peruvianus have both types of sexine structure. Pollen analysis of other genera of Mutisieae subtribes Nassauviinae, Mutisiinae and Gochnatiinae demonstrate two new exine types: (1) Ainsliaea type, with two sublayers poorly distinguishable, the exine appearing compact, the outer surface microechinate; and (2) Wunderlichia type, with two well-differentiated sublayers, the outer surface echinate, the spines with apical channels. The results show that: (1) Proustia and Lophopappus cannot be differentiated from each other by pollen characters; (2) the genera of subtribe Nassauviinae can be differentiated from the other two subtribes by having sexine sublayers with similar structure; (3) Proustia and Lophopappus have the pollen exine structural types that are typical of pollen of subtribe Nassauviinae; (4) subtribes Gochnatiinae and Mutisiinae are characterized by having sexine sublayers with different structures; but (5) those two subtribes cannot be differentiated based on pollen characters.

Early history of Asteraceae in Patagonia: Evidence from fossil pollen grains

Abstract The Asteraceae are classified into three subfamilies: Barnadesioideae, Cichorioideae, and Asteroideae. It has been suggested that the southern South American subfamily Barnadesioideae is the basal branch of the phylogenetic tree of the family, and Patagonia is the ancestral area of Asteraceae. Here we explore the chronological records of some members of the family, with findings of Mutisiinae (tribe Mutisieae, subfamily Cichorioideae) from the Late oligocene (28–23 Ma) and of Barnadesioideae and Nassauviinae (Mutisieae) from the early Miocene (23–20 Ma), all recovered from marine deposits of Patagonia. even though the succession of fossil appearances (first Mutisieae) differs from that provided by molecular data (first Barnadesioideae), this new scheme offers additional evidence towards the understanding of the early history of ancestral Asteraceae.

Native vs. introduced bee flora: a palynological survey of honeys from Uruguay

SUMMARYA melissopalynological study was made to classify the botanical and geographical origin of 21 samples of commercial Uruguayan honeys. Sixty-six pollen types were found; 67% of the samples were unifloral. The taxa with the greatest frequencies (> 15% of pollen in each sample) were Lotus corniculatus, Eucalyptus spp., Echium plantagineum, Scutia buxifolia and Baccharis spp. The taxa with highest occurrence (present in > 85% of samples) were Eucalyptus spp., Trifolium pratense, L corniculatus, Schinus molle-type, Baccharis spp., Trifolium repens, Echium plantagineum, Eryngium spp., Scutia buxifolia, Salix humboldtiana and Poaceae. Forty-eight percent of the pollen taxa were endemic to the Americas; the majority of the other taxa were from Europe. The Uruguayan honeys we analysed typically contained pollen from the native Schinus molle type, Baccharis spp., Eryngium spp., Scutia buxifolia and Salix humboldtiana, together with pollen from the introduced Eucalyptus spp., L corniculatus, T. pratense, T. r...

The unusual occurrence of tricolpate pollen within Mutisieae (Asteraceae)

The monotypic genus Hecastocleis and species of Ainsliaea DC. (Asteraceae, Mutisieae) have tricolpate pollen, which is unusual in Asteraceae. The pollen morphology of H. shockleyi and species of Ainsliaea were studied with light microscope and scanning electron microscope. Pollen of H. shockleyi and some species of Ainsliaea have tricolpate aperture but differ in size and exine features. The pollen of Ainsliaea is bigger than that of Hecastocleis, and has more conspicuous microspines, a Mutisia‐ or an Ainsliaea‐ exine type, and is slightly thickened at the poles. The pollen of H. shockleyi is scabrate‐microechinate with small puncta, and has the Mutisia‐exine type, which is regularly thickened over the complete grain. The occurrence of tricolpate pollen supports previous studies that Hecastocleis and Ainsliaea stand apart from other genera of Mutisieae, but the occurrence of Mutisia‐exine type does not suggest complete independence of the tribe.

Salcedoa gen. nov., a Biogeographic Enigma in the Caribbean Mutisieae (Asteraceae)

Abstract A new genus, Salcedoa, is described from the Cordillera Septentrional, northern Dominican Republic. The bilabiate florets, smooth style branches, caudate anthers, and pollen grains size and shape, exine structure and sculpture, and endoaperture shape place it close to the South American genera of the tribe Mutisieae (Asteraceae) centered in the Guayana Shield. Two morphology-based phylogenetic analyses, one using Gochnatia and the other using Chaetanthera as outgroups, and including Salcedoa and the 12 Guayanan genera were performed to determine the sister group relationships of Salcedoa. The results suggest that Salcedoa is sister to Gongylolepis. The unusual distributional pattern of Salcedoa and the Guayanan genera was explored through the dispersal-vicariance method. A trans-oceanic dispersal of fruits is postulated as a probable mechanism by which Salcedoa reached Hispaniola from a South American ancestor.