scholarly journals Achnanthes citronella, A. trachyderma comb. nov. (Bacillariophyta) and allied taxa pertaining to the same morphological group

Phytotaxa ◽  
2015 ◽  
Vol 227 (2) ◽  
pp. 101 ◽  
Author(s):  
Catherine Riaux-gobin ◽  
Pierre Compère ◽  
Friedel Hinz ◽  
Luc Ector

Several diatoms in the family Achnanthaceae (Bacillariophyta), mainly from marine environments, have species with strongly apiculate, lemon-shaped valves. Some of them originally described under the genus Cocconeis (i.e., C. trachyderma or C. citronella), while others were first described as Stauroneis species [i.e. Stauroneis apiculata or S.(?) obesa]. Afterwards, Cocconeis citronella has been recombined within Achnanthes by Hustedt. The type material of C. citronella from Albert Mann’s collection, housed in the Smithsonian Institution (US), has been examined with light microscope; some ambiguities are pointed out and new details added to the original description. The intricate history of the latter taxon is redrawn and comparison with allied taxa are tentatively addressed. Cocconeis trachyderma is lectotypified and recombined as Achnanthes trachyderma comb. nov. Stauroneis apiculata and S.(?) obesa are recombined as Achnanthes apiculata comb. nov. and Achnanthes obesa comb. nov. respectively. The examination with light and scanning electron microscope of several marine samples from the Society Archipelago details the unique morphology of Achnanthes trachyderma which, until recently, has been often misidentified as Achnanthes citronella due to certain similarities between both taxa.

1985 ◽  
Vol 63 (3) ◽  
pp. 611-615 ◽  
Author(s):  
Kevin D. Hyde ◽  
E. B. Gareth Jones

Collections of filamentous marine fungi in Seychelles included Nimbospora effusa Koch and an undescribed species, Nimbospora bipolaris Hyde & Jones sp. nov. Tha latter differs from N. effusa in the size of the ascospores and in ascospore appendage morphology. Both species are illustrated by light microscope and scanning electron microscope micrographs.


IAWA Journal ◽  
2002 ◽  
Vol 23 (1) ◽  
pp. 83-96 ◽  
Author(s):  
Ryogo Nakada ◽  
Kaichiro Kawamura

The anatomy of tawara-shibo stems of Chamaecyparis obtusa (Siebold & Zucc.) Endl. was observed using a scanning electron microscope (SEM) and a light microscope. Tawara-shibo is a strange stem form with a series of swellings that appear at regular intervals along the stem axis. Multiseriate rays, trabeculae and related structures, and modified tracheids were frequently observed at swollen portions. These features were less frequent at non-swollen portions.We conclude that abnormal cambial activities, occurring at regular longitudinal intervals, cause the formation and development of these three anatomical features and higher growth rates at swollen portions. As a result of differences in growth rate between swollen and non-swollen portions, the stem form of tawara-shibo develops. It is suggested that formation of the characteristics observed in tawara-shibo stems is genetically controlled by hormonal secretion into or within the cambium.


2017 ◽  
pp. 117 ◽  
Author(s):  
Victoria Sosa

This work studies 17 species of mexican Araliaceae from the palynological point of view belonging to the genera Aralia, Dendropanax, Didymopanax, Redera, Oreopanax y Sciadodendron . All the pollen descriptions are presented at the generic level. The grains were studied based in scanning electron microscope and light microscope. It includes a dichotomous key for the genera grains. The results showed few differences between the pollen grains of the genera although some exine characters are important. Redera and Didymopanax presented an exine semi-tectate and the rest of the genera had tectate-perforate grains. This paper compared also some pollen characters with morphological ones, finding pollen characters considered primitive correlated with characters of primitive Araliaceae groups .


2009 ◽  
Vol 69 (4) ◽  
pp. 1059-1071 ◽  
Author(s):  
M. Garcia ◽  
C. Odebrecht

The detailed description of rarely recorded Thalassiosira species in Brazil is presented with light microscope (LM) and scanning electron microscope (SEM) illustrations. A total of 78 phytoplankton net samples (20 µm) collected between the years 2000 and 2006 in coastal waters of southern Brazilian, Cassino Beach and the estuary of Lagoa dos Patos, were studied in cleaned material using the Axiovert Zeiss LM and Jeol 6060 SEM. Water temperature and salinity of samples and six species are presented: Thalassiosira endoseriata, T. hendeyi, T. lundiana, T. minuscula, T. oceanica and T. wongii. Two species, Thalassiosira hendeyi and T. endoseriata were the most common being observed in all seasons at Cassino Beach in a wide temperature range (10-26 ºC), while only sporadically in the estuary of Lagoa dos Patos. Thalassiosira endoseriata, T. lundiana, T. oceanica and T. wongii are for the first time reported in Brazilian coastal waters. The latter two species, rarely recorded in the world, are fully illustrated based on Brazilian material.


Phytotaxa ◽  
2021 ◽  
Vol 516 (3) ◽  
Author(s):  
PRADIP VIKRAM DESHMUKH ◽  
SIDDHARTHAN SURVESWARAN ◽  
RAMCHANDRA DNYANOBA GORE ◽  
MANOJ MADHWANAND LEKHAK

The endemic Indian genus Haplanthodes (Acanthaceae) is revised. Four species, viz. H. neilgherryensis, H. plumosa, H. tentaculata and H. verticillata and a new variety, H. neilgherryensis var. toranganensis are recognized. Lectotype is designated for Haplanthodes, Haplanthus plumosus and H. verticillaris. The nomenclature of the Linnaean name Ruellia tentaculata is also discussed. Micromorphology of seed using light microscope (LM) and scanning electron microscope (SEM) is observed for the first time, and two types, reticulate and micro papillate, have been recognized based on surface sculpturing pattern. The genus differs from the related genera Andrographis and Haplanthus by distinctly two grooved seeds with hygroscopic hairs. Pollen grains of the genus are oblate or prolate spheroidal, distinctly triangular, trizonocolporate with reticulate exine ornamentation.


2020 ◽  
Vol 11 (2) ◽  
pp. 486-492
Author(s):  
Jens Anibal Juul ◽  
Vegard Asgeir Forsaa ◽  
Tor Paaske Utheim ◽  
Endre Willassen

We present a case report of periocular Loa loa. The key feature of L. loa distinguishing it from other human filarial parasites are cuticular bosses, which are presented in images from a light microscope and a scanning electron microscope. The cuticular bosses could be divided into three subtypes not previously described.


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