scholarly journals Palinología de Agavaceae, una contribución biosistemática

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).

2021 ◽  
Vol 95 ◽  
Author(s):  
F.B. Drago ◽  
M. Dueñas Díaz ◽  
R. Draghi ◽  
V. Núñez

Abstract An annotated checklist of the cestode parasites of Argentinean wild birds is presented, as the result of a compilation of parasitological papers published between 1900 and April 2021. This review provides data on hosts, geographical distribution, sites of infection, location of material deposited in helminthological collections, references and taxonomic comments. A host/parasite list is also provided. During this period, 38 papers were published that gather information about 34 cestode nominal species and 11 taxa identified at generic level, belonging to three orders, ten families and 35 genera. The highest number of cestode taxa was recorded in the family Hymenolepididae, with 12 nominal species and two taxa identified at generic level, followed by Dilepididae, with eight nominal species and three taxa identified at generic level. Of the 1042 species of birds reported in Argentina, only 29 (2.8%) were reported as hosts of adult cestodes. The families of birds with the highest number of reported taxa were Laridae and Anatidae, with 20 and 14 taxa, respectively.


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.


Zootaxa ◽  
2012 ◽  
Vol 3313 (1) ◽  
pp. 53 ◽  
Author(s):  
HAILIN YANG ◽  
HU LI ◽  
XUN DAI ◽  
JIAN CHANG ◽  
WANZHI CAI

Some cytogenetic aspects of six Chinese species of Coreoidea were studied. The material included five species from the familyCoreidae: Hydarella orientalis (Distant), Homoeocerus bannaensis Hsiao, Cletus graminis Hsiao & Cheng, Paradasynus lon-girostris Hsiao, Acanthocoris scaber (Linnaeus), and one species from the family Stenocephalidae: Stenocephalus femoralisReuter. All species show holokinetic chromosomes, post-reductional meiotic division of XO sex chromosomes, a pre-reduc-tional type of meiosis for autosomes and m-chromosomes, intersticial chiasmata in most autosomes, and one chiasma per biva-lent in male meiosis. In the species studied, the diploid chromosome number ranged from 13 to 21. It was 13 in S. femoralis (10+ 2m + XO), 15 in Hy. orientalis (12 + 2m + XO), 17 in Ho. bannaensis (14 + 2m + XO) and C. graminis (14 + 2m + XO), 19in P. longirostris (16 + 2m + XO), and 21 in A. scaber (18 + 2m + XO). Hy. orientalis represents the first cytogenetically stud-ied species in subfamily Hydarinae. The phylogenetic relationships among Coreoidea are briefly discussed from a cytogenetic point of view.


2003 ◽  
Vol 60 (3) ◽  
pp. 533-568 ◽  
Author(s):  
J. C. MANNING ◽  
P. GOLDBLATT ◽  
M. F. FAY

A revised generic synopsis of sub-Saharan Hyacinthaceae is presented, based on a molecular phylogenetic analysis of the family. Generic rank is accorded only to reciprocally monophyletic clades that can be distinguished by recognizable morphological discontinuities, thereby permitting an appropriate generic assignment of species not included in the analysis. Three subfamilies are recognized within the region. Subfamily Ornithogaloideae, characterized by flattened or angular seeds with tightly adhering testa, is considered to include the single genus Ornithogalum, which is expanded to include the genera Albuca, Dipcadi, Galtonia, Neopatersonia and Pseudogaltonia. Recognizing any of these segregates at generic level renders the genus Ornithogalum polyphyletic, while subdivision of Ornithogalum into smaller, morphologically distinguishable segregates in order to preserve the monophyly of each is not possible. Subfamily Urgineoideae, characterized by flattened or winged seeds with brittle, loosely adhering testa, comprises the two mainland African genera Bowiea and Drimia. The latter is well circumscribed by its deciduous, short-lived perianth and includes the previously recognized genera Litanthus, Rhadamanthus, Schizobasis and Tenicroa. The monotypic Madagascan Igidia is provisionally included in the subfamily as a third genus on the basis of its seeds, pending molecular confirmation of its relationships. Subfamily Hyacinthoideae resolves into three clades, distinguished as tribes Hyacintheae (strictly northern hemisphere and not treated further), Massonieae and Pseudoprospereae tribus nov. Full descriptions and a key to their identification are provided for all genera. New combinations reflecting the generic circumscriptions adopted here are made for most African and all Indian and Madagascan species.


Mathematics ◽  
2021 ◽  
Vol 9 (16) ◽  
pp. 1835
Author(s):  
Antonio Barrera ◽  
Patricia Román-Román ◽  
Francisco Torres-Ruiz

A joint and unified vision of stochastic diffusion models associated with the family of hyperbolastic curves is presented. The motivation behind this approach stems from the fact that all hyperbolastic curves verify a linear differential equation of the Malthusian type. By virtue of this, and by adding a multiplicative noise to said ordinary differential equation, a diffusion process may be associated with each curve whose mean function is said curve. The inference in the resulting processes is presented jointly, as well as the strategies developed to obtain the initial solutions necessary for the numerical resolution of the system of equations resulting from the application of the maximum likelihood method. The common perspective presented is especially useful for the implementation of the necessary procedures for fitting the models to real data. Some examples based on simulated data support the suitability of the development described in the present paper.


Phytotaxa ◽  
2016 ◽  
Vol 273 (2) ◽  
pp. 141 ◽  
Author(s):  
EUGENY V. BOLTENKOV

Iris aphylla Linnaeus (1753: 38) (Iridaceae) is a highly variable species from the morphological point of view, especially in the height of stem, stem branching, size of leaves, and color of flowers. Moreover, it can be found in different habitats. In the Middle-Russian Upland, this plant is mostly associated with meadow steppes on slopes and, rarely, with edges of shrub thickets; also occurs along forest edges and in open forests, where blooming plants are rare (Kazakova et al. 2015). It is native to Central, Eastern, and some parts of Western Europe. The species is widespread in the Ukraine and mainly in the south of middle European Russia, while in the European countries its populations are sparser. Iris aphylla is of autotetraploid origin (Mitra 1956); plants with the chromosome number 2n = 48 are found more frequently in Europe (Wróblewska et al. 2010). Its numerous synonyms, including four subspecies, indicate the variability of this species. The genetic data confirm the conclusion that the subspecies of I. aphylla should be regarded as a single species (Wróblewska et al. 2010). According to my best knowledge (see also Jarvis 2007) the name I. aphylla is still lacking typification.


PEDIATRICS ◽  
1965 ◽  
Vol 35 (4) ◽  
pp. 589-595
Author(s):  
John Lorber

1. The family histories of 722 infants who were born with spina bifida cystica were studied. 2. The index cases were referred for surgical treatment and were not selected in any way from the genetic point of view. 3. Intensive inquiries were made to obtain a complete family pedigree, including a prospective follow-up of siblings born after the index case. 4. Of 1,256 siblings 85 or 6.8% had gross malformation of the central nervous system: spina bifida cystica in 54, anencephaly in 22, and uncomplicated hydrocephalus in 9. 5. Of 306 children born after the index case 25 (8%) or 1 in 12 were affected. 6. There was a progressive increase in multiple cases in the family with increasing family size. In sibships of five or more, multiple cases occurred in 24.1%. 7. In 118 families cases of gross malformation of the central nervous system were known to have occurred among members of the family other than siblings. Cases occurred in three generations. 8. It is possible that spina bifida cystica might be a recessively inherited condition.


Author(s):  
M. Rodríguez

Abstract A description is provided for Meliola mangiferae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. DISEASE: Meliola mangiferae, as with the family Meliolaceae in general, is found on living leaves parasitizing the epidermis and sometimes deeper tissues, but without production of obvious disease symptoms. HOSTS: Mangifera indica, M. rigida and Mangifera sp. (Hansford, 1961). GEOGRAPHICAL DISTRIBUTION: Brazil, British Guiana, Costa Rica, Cuba, India, Indonesia (Java), Jamaica, Malaysia, Panama, Philippines, Puerto Rico, Surinam, Trinidad & Tobago, Venezuela. Meliola mangiferae is found in practically all areas of mango cultivation, with the exception of Africa and Australia (Hansford, 1961). TRANSMISSION: By air-borne ascospores.


Phytotaxa ◽  
2021 ◽  
Vol 501 (1) ◽  
pp. 151-161
Author(s):  
ER-HUAN ZANG ◽  
MING-XU ZHANG ◽  
WEN-LE WANG ◽  
CHUN-HONG ZHANG ◽  
MIN-HUI LI

In May 2020, a new taxon of Euphorbia, Euphorbiaceae was collected from a dry hillside of Dongsheng District, Ordos City, Inner Mongolia. The morphological characteristics of the specimens analyzed differ from those of the known Euphorbia species from this region; therefore, we suspected this may be a new species, and we set to analyze the ITS2 sequences of some Euphorbia species. The results show that the new taxon belongs to the sect. Esula of Euphorbia subg. Esula. It is similar to Euphorbia esula (description from Flora of China) but does not belong to the same species. Concomitantly, plant morphological data and pollen morphology results show significant differences between the new taxon, E. esula and E. caesia, a finding that supports the delimitation of this new taxon, which is named Euphorbia mongoliensis in accordance with its geographical distribution.


Sign in / Sign up

Export Citation Format

Share Document