A revised chitinozoan classification

1999 ◽  
Vol 73 (4) ◽  
pp. 549-570 ◽  
Author(s):  
Florentin Paris ◽  
Yngve Grahn ◽  
Viiu Nestor ◽  
Iskra Lakova

The successful definition of chitinozoan genera depends primarily on the precision of the criteria used. A standardized morphological terminology based upon details from scanning electron microscope observations of the most representative taxa bearing these characters is therefore proposed. The 143 genera, or subgenera, described so far in the literature are reviewed in order to exclude invalid taxa and obvious junior synonyms. Particular attention is paid to preventing the overlap of generic definitions of the 56 genera ultimately retained. A brief account of the diagnostic features and stratigraphic range of selected genera is given, and basic information concerning the type material of these genera is listed. Finally, a suprageneric classification of the whole Chitinozoa group based on diagnostic features whose hierarchy is established on statistical and evolutionary grounds, is given. One new subfamily, Pogonochitininae, three new genera, Baltochitina, Hyalochitina, and Saharochitina, and a new species Baltochitina nolvaki, are defined. The subspecies Fungochitina fungiformis spinifera is elevated to a specific rank.

Nematology ◽  
2002 ◽  
Vol 4 (3) ◽  
pp. 403-419 ◽  
Author(s):  
James Baldwin ◽  
Paul De Ley ◽  
Manuel Mundo-Ocampo ◽  
Steven Nadler ◽  
S. Patricia Stock ◽  
...  

AbstractA detailed morphological description (light and scanning electron microscope observations) is given of two isolates currently used in molecular and developmental studies: PDL0024, Panagrobelus stammeri Rühm, 1956 and PDL0025, a new species herein described as Plectonchus hunti n. sp. We redescribe the lip region, interpret the orientation of the lips in P.stammeri and provide additional morphological and morphometric diagnostic features. Plectonchus hunti n. sp. is characterised by the bifurcating spicule tip and by the placement of the male genital papillae in a 3/3 + p + 2 arrangement. Additionally, females of this new species can be differentiated from other species of Plectonchus by the more anterior position of the vulva, the more anterior location of the excretory pore and the tail morphology. An emended diagnosis for this genus is provided. In this study we demonstrate that both studied taxa share morphological similarities, such as the presence of a 'cephaloboid-type' spermatheca. Our observations also indicate slight but consistent differences in cell composition of the female reproductive system between these two taxa.


Author(s):  
J. D. Hutchison

When the transmission electron microscope was commercially introduced a few years ago, it was heralded as one of the most significant aids to medical research of the century. It continues to occupy that niche; however, the scanning electron microscope is gaining rapidly in relative importance as it fills the gap between conventional optical microscopy and transmission electron microscopy.IBM Boulder is conducting three major programs in cooperation with the Colorado School of Medicine. These are the study of the mechanism of failure of the prosthetic heart valve, the study of the ultrastructure of lung tissue, and the definition of the function of the cilia of the ventricular ependyma of the brain.


Author(s):  
Michael T. Postek

The term ultimate resolution or resolving power is the very best performance that can be obtained from a scanning electron microscope (SEM) given the optimum instrumental conditions and sample. However, as it relates to SEM users, the conventional definitions of this figure are ambiguous. The numbers quoted for the resolution of an instrument are not only theoretically derived, but are also verified through the direct measurement of images on micrographs. However, the samples commonly used for this purpose are specifically optimized for the measurement of instrument resolution and are most often not typical of the sample used in practical applications.SEM RESOLUTION. Some instruments resolve better than others either due to engineering design or other reasons. There is no definitively accurate definition of how to quantify instrument resolution and its measurement in the SEM.


Diversity ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 213
Author(s):  
M. Hossain ◽  
Pat Hutchings

A new species of glycerid polychaete, Glycera sheikhmujibi, is described from the saltmarsh on the central coast of Bangladesh. The species is identified based on morphological characteristics using both a light microscope and scanning electron microscope (SEM). The species is characterized by the presence of three distinct types of proboscideal papillae: type 1 papillae (conical with three transverse ridges), type 2 (conical with a straight, median, longitudinal ridge), and type 3 (round, shorter, and broader, with a straight, median, longitudinal ridge). It has a Y-shaped aileron with gently incised triangular base, almost equal-size digitiform noto- and neuropodial lobes in the mid-body, and long ventral cirri at the posterior end. The new species is compared with its related species, previously described from the Bay of Bengal region. A key to all these species is provided.


Phytotaxa ◽  
2018 ◽  
Vol 373 (3) ◽  
pp. 169 ◽  
Author(s):  
YUE CAO ◽  
PAN YU ◽  
QINGMIN YOU ◽  
REX L. LOWE ◽  
DAVID M. WILLIAMS ◽  
...  

A new species of Tabularia, Tabularia sinensis, is described from the inland Poyang Lake (Jiangxi Province), the largest lake in China. The description is based on light and scanning electron microscope observations of valve and girdle elements. Given the diversity of forms in the genus, the relationships and status of the genus was investigated in the context of the other known species in the genus and to ascertain if Tabularia, as originally circumscribed, remains monophyletic.


Zootaxa ◽  
2020 ◽  
Vol 4729 (1) ◽  
pp. 138-144
Author(s):  
FLAVIO ROBERTO DE ALBUQUERQUE ALMEIDA ◽  
FERNANDO DA SILVA CARVALHO-FILHO ◽  
ALEXANDER KNYSHOV ◽  
JOSE ANTONIO MARIN FERNANDES

The genus Voragocoris Weirauch, 2012 is composed of Voragocoris schuhi Weirauch, 2012 and Voragocoris amrishi Makhan, 2013, previously recorded from Peru and Suriname, respectively. In this paper, a new species, Voragocoris weirauchae sp.n., is described based on specimens collected in the Brazilian Amazon, representing the first record of the genus from Brazil. We provide diagnosis, description, photographs of habitus, and scanning electron micrographs of the diagnostic features. A key to species based on males of Voragocoris is also presented. 


1986 ◽  
Vol 64 (10) ◽  
pp. 2207-2210 ◽  
Author(s):  
Eveline Guého ◽  
Charles De Vroey

Anixiopsis biplanata sp.nov. is described as a new ascomycete isolated from soil at an altitude of 3100 m in Nepal. It is heterothallic and characterized by small, reddish brown ascospores (4 × 3 μm), which under the light microscope seem subrectangular to hexagonal in side view and appear smooth walled. Under the scanning electron microscope, however, they are tire shaped, ornamented with an equatorial reticulum and with two smooth, flat, lateral discs. Its anamorph is a Chrysosporium. Anixiopsis biplanata is briefly compared with the three other species already included in the genus Anixiopsis Hansen.


Phytotaxa ◽  
2020 ◽  
Vol 455 (4) ◽  
pp. 295-300
Author(s):  
SAÚL BLANCO ◽  
CLAUDIA L. MUÑOZ-LÓPEZ ◽  
CARLOS A. RIVERA-RONDÓN

A new species, Nupela eremica sp. nov. is described from a high mountain lake located in the Eastern Range of Colombian Andes. The new taxon was studied from sediment and epiphyton samples and under light and scanning electron microscope. Comparison with morphologically similar taxa is showed. N. giluwensis, N. carolina, N. gomphosphenioides, N. encyonopsis, N. incerta, N. neglecta, N. tenuicephala, and N. exilissima show morphometric values overlapping those of Nupela eremica sp. nov. The combination of valve size and outline is unique and justifies the erection of this new species.


Zootaxa ◽  
2004 ◽  
Vol 397 (1) ◽  
pp. 1 ◽  
Author(s):  
JUNGSUN YOO ◽  
JOOPIL KIM ◽  
HOZUMI TANAKA

Alopecosa volubilis n. sp. is described from Korea and is differentiated from other species in Alopecosa Simon, 1885 by morphological characteristics, such as three retromarginal teeth of chelicera, smaller body size, and the presence of a distinct tip of the median apophysis. The pedipalpal sclerites and somatic characters of two similar species, A. moriutii Tanaka, 1985 and A. hokkaidensis Tanaka, 1985, are compared with those of the new species. An illustration of the body and scanning electron microscope (SEM) pictures of the pedipalpal organ are provided.


Phytotaxa ◽  
2017 ◽  
Vol 308 (2) ◽  
pp. 275
Author(s):  
MOAAKUM MOA ◽  
SANTANU DEY ◽  
WOJCIECH ADAMOWSKI ◽  
RAJIB GOGOI

Impatiens nagorum from Fakim Wildlife Sanctuary, Nagaland, Northeast India, is described and illustrated. Detailed descriptions, distribution, and ecological information, along with colour photographs of the plant, as well as micromorphology of seeds and pollen grains under scanning electron microscope (SEM) are presented.


Sign in / Sign up

Export Citation Format

Share Document