scholarly journals The Biodiversity of Demodecid Mites (Acariformes: Prostigmata), Specific Parasites of Mammals with a Global Checklist and a New Finding for Demodex sciurinus

Diversity ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 261
Author(s):  
Joanna N. Izdebska ◽  
Leszek Rolbiecki
Keyword(s):  
Geographic Distribution ◽  
Taxonomic Diversity ◽  
Diagnostic Methods ◽  
Valid Species ◽  
Distribution Data ◽  
Medical Study ◽  
Parasite Relationship ◽  
New Finding ◽  
Parasitic Mites ◽  
Host Parasite

Demodecidae are the most specialized parasitic mites of mammals; they typically inhabit the skin, but they have been found in other tissues and organs. They can cause demodecosis (a disease which is hazardous and difficult to cure) in humans, domestic animals and livestock. They are parasites with high host and topical specificity. They have been found for most orders of mammals, and they are common in the populations of numerous host species. Therefore, they not only constitute an important subject of veterinary and medical study, but also comprise an excellent model for faunistic and parasitological analyses concerning different aspects of functioning and evolution of the host–parasite relationship. The current level or knowledge of demodecid mites is irregular and fragmentary, and numerous questions require elaboration and ordering, from the taxonomic diversity to geographic distribution and relations with hosts. Such data may be of use i.a. for the development of more efficient and reliable diagnostic methods, as well as understanding the etiology and pathogenesis mechanisms of demodecosis, currently a contentious issue. The present paper lists all formally-described valid species of demodecid mites, together with other functioning specific names, verified and with comments on their status. This is significant for correct species identification and demodecosis diagnostics. The list has been drawn up on the basis of data acquired in the period 1842−2020. It contains 122 valid species of parasite, including their hosts and geographic distribution, data on parasitism, as well as only the second record of Demodex sciurinus in Eurasian red squirrel Sciurus vulgaris in over 100 years since its initial discovery.

Susceptibilities of Various Snail Intermediate Hosts of Schistosoma mansoni to Different Strains of the Parasite

1965 ◽  
Vol 39 (4) ◽  
pp. 363-376 ◽  
Author(s):  
M.F.A. Saoud
Keyword(s):  
Puerto Rico ◽  
Schistosoma Mansoni ◽  
Intermediate Hosts ◽  
Considerable Evidence ◽  
The Past ◽  
Host Parasite Relationship ◽  
Parasite Relationship ◽  
Different Strains ◽  
Host Parasite ◽  
Comprehensive Studies

In the past two decades, considerable evidence has accumulated in the literature about the differences in the susceptibility of various intermediate hosts of Schistosoma mansoni to different strains of the parasite. Comprehensive studies on this aspect of host-parasite relationship have been published by Files & Cram (1949), Abdel-Malek (1950) and Files (1951). The results of more recent studies have been reported by Wright (1962) and Saoud (1964).In the present paper, the writer has studied the susceptibility of four intermediate hosts of S. mansoni from Brazil, Puerto Rico, Egypt and Tanganyika to some strains of the parasite.

Certain aspects of the host-parasite relationship ofNematospiroides dubius(Baylis). II. The effect of sex on experimental infections in the rat (an abnormal host)

Parasitology ◽  
1961 ◽  
Vol 51 (3-4) ◽  
pp. 499-510 ◽  
Author(s):  
Colin Dobson
Keyword(s):  
Male Rats ◽  
Male Rat ◽  
Normal Male ◽  
Female Rat ◽  
Castrate Male ◽  
Parasite Relationship ◽  
Nematospiroides Dubius ◽  
Resistance To Infection ◽  
Host Parasite ◽  
The Relationship

1. The male rat is more susceptible to infections ofNematospiroides dubiusthan the female. As the rat grows older the resistance of the female rat to infection increases at a greater rate than that of the male.2. The course of the infection is modified by the sex of the host.3. More larvae penetrated the intestinal mucosa to encyst in the male than in the female. More larvae, however, formed cysts in the female than in the male rat by the fifth day.4. The male harboured more adult worms than the female rat, although this difference was not significant in the immature animals.5. The sex resistance of the rat toN. dubiusinfections was removed by bilateral gonadectomy. Castration decreased the susceptibility of the male rat, while spaying increased it in the female compared with the susceptibility in the respective normal hosts.6. Subsequent replacement of the homologous sex hormone in the gonadectomized rat restores the sex resistance, and may even increase it (particularly in the immature animals). Oestradiol increased the resistance of the spayed female rat, while testosterone increased the susceptibility of the castrate male rat to infection.7. Oestradiol implanted in castrate male rats increased the resistance of these hosts to a greater level than was shown in the normal male rat.8. The rat shows a marked age resistance over which the sex resistance is superimposed.9. The relationship between the sex of the host and its resistance to infection is discussed.This work was done during the tenure of a Department of Scientific and Industrial Research Studentship. My thanks are due to Dr E. T. B. Francis for his helpful and critical supervision and to Professor I. Chester Jones, in whose department the work was done, for the facilities he provided.

An update to the taxonomy of the genus Macroderes Westwood 1842 (Coleoptera: Scarabaeidae: Scarabaeinae) with descriptions of new species from South Africa

Zootaxa ◽  
2018 ◽  
Vol 4504 (1) ◽  
pp. 41
Author(s):  
ISHTIAG H. ABDALLA ◽  
CHRISTIAN M. DESCHODT ◽  
CLARKE H. SCHOLTZ ◽  
CATHERINE L. SOLE
Keyword(s):  
South Africa ◽  
New Species ◽  
Geographic Distribution ◽  
Extreme Points ◽  
Valid Species ◽  
The South ◽  
Diagnostic Characters ◽  
Incertae Sedis

The genus Macroderes Westwood, 1842 (Scarabaeidae: Scarabaeinae, tribe incertae sedis) is practically endemic to South Africa with only one species that is found little north in southern Namibia. The ranges of the species are limited to the winter-fall and bimodal biomes of South Africa comprising the regions of Richtersveld as extreme points of its northerly distribution, and extending to the south through Namaqualand to Cape Agulhas. The taxonomy of the genus is revised. Fourteen valid species are recognised and three others are of doubtful validity. Seven new species are described, these are: M. cederbergensis Abdalla & Deschodt, new species, M. tortuosus Abdalla & Scholtz, new species, M. gifboomi Abdalla & Scholtz, new species, M. leipoldti Abdalla & Deschodt, new species, M. oreatus Abdalla & Deschodt, new species, M. porselinus Abdalla, new species, and M. soleiana Abdalla & Deschodt, new species. Macroderes nitidus Harold, 1877 is redescribed and its lectotype is designated. The diagnostic characters as well as an updated geographic distribution of each species are summarised. An updated key of the genus, photographs of habitus, sclerites of internal sac, pronotum, pronotal punctures and elytra also are provided. 

scholarly journals Host-parasite relationship during Epistylis sp. (Ciliophora: Epistylididae) infestation in farmed cichlid and pimelodid fish

2016 ◽  
Vol 51 (5) ◽  
pp. 520-526 ◽  
Author(s):  
Santiago Benites de Pádua ◽  
Maurício Laterça Martins ◽  
Gustavo Moraes Ramos Valladão ◽  
Laura Utz ◽  
Fernando José Zara ◽  
...  
Keyword(s):  
The Body ◽  
Farmed Fish ◽  
Hydropic Degeneration ◽  
Ulcer Disease ◽  
Opportunistic Bacteria ◽  
Parasite Relationship ◽  
Hemorrhagic Ulcer ◽  
Host Parasite ◽  
Portal Of Entry

Abstract: The objective of this work was to describe the host-Epistylis sp. relationship during infestation on farmed fish. Five Nile tilapia (Oreochromis niloticus) and ten hybrid surubim catfish (Pseudoplatystoma reticulatum x P. corruscans), all diseased, were used for in vivo morphological analysis of sessile peritrichs by contrast microscopy. Fragments of infected tissues were subjected to histological processing and scanning electron microscopy. Epistylis sp. caused hemorrhagic ulcer disease, and cichlids were more prone to develop infestations throughout the body surface due to the attachment of the colonies to the scales, which did not occur with pimelodids. Multifocal granulomatous dermatitis was observed, associated with the hydropic degeneration of the epithelium and to ulcerative areas of necrosis. Microscopic examination showed the presence of bacterial microflora associated to Epistylis sp. peduncles. Therefore, this species can be considered a portal of entry for opportunistic bacteria.

scholarly journals Biodiversity Inventory and Distribution of Metriorrhynchina Net-Winged Beetles (Coleoptera: Lycidae), with the Identification of Generic Ranges

Insects ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 710
Author(s):  
Ladislav Bocak ◽  
Michal Motyka ◽  
Dominik Kusy ◽  
Renata Bilkova
Keyword(s):  
Solomon Islands ◽  
New Guinea ◽  
The Philippines ◽  
Species Level ◽  
Valid Species ◽  
Distribution Data ◽  
Generic Level ◽  
Biodiversity Inventory ◽  
Australian Continent ◽  
Northern Edge

We reviewed the species-level classification of Metriorrhynchina net-winged beetles to make the group accessible for further studies. Altogether, 876 valid species are listed in a checklist along with known synonyms, combinations, and distribution data. The compilation of geographic distribution showed that Metriorrhynchina is distributed mainly in the Australian region with very high diversity in the islands at the northern edge of the Australian craton, i.e., in the Moluccas and New Guinea (54 and 423 spp. respectively). The neighboring northern part of the Australian continent houses a majority of known Australian species (112 spp.) and the diversity of net-winged beetles gradually decreases to the south (43 spp.). The fauna of Sulawesi is highly endemic at the generic level (4 of 10 genera, 67 of 84 spp.). Less Metriorrhynchina occur in the Solomon Islands and Oceania (in total 22 spp.). The Oriental Metriorrhynchina fauna consists of a few genera and a limited number of species, and most of these are known from the Philippines (51 of 94 Oriental spp.). We identified a high species level turn-over between all neighboring landmasses. The genus-level endemism is high in Sulawesi (4 genera) and New Guinea (11 genera), but only a single genus is endemic to Australia. During the compilation of the checklist, we identified some homonyms, and we propose the following replacement names and a new synonym: Metriorrhynchus pseudobasalis, nom. nov. for M. basalis Lea, 1921 nec M. basalis Bourgeois, 1911; Metriorrhynchus pseudofunestus, nom. nov. for M. funestus Lea, 1921 nec M. funestus (Guérin-Méneville, 1838), Trichalus pseudoternatensis, nom. nov. for T. ternatensis Kleine, 1930 nec T. ternatensis Bourgeois, 1900, Procautires subparallelus, nom. nov. for P. parallelus (Pic, 1926) nec P. parallelus (Bourgeois, 1883), and Cautires pseudocorporaali, nom. nov. for C. corporaali (Pic, 1921: 12), (formerly Odontocerus and Cladophorus) nec C. corporaali (Pic, 1921) (formerly Bulenides, later Cautires). Diatrichalus biroi Kleine, 1943, syn. nov. is proposed as a junior subjective synonym of D. subarcuatithorax (Pic, 1926). Altogether, 161 new combinations are proposed, and 47 species earlier placed in Xylobanus Waterhouse, 1879 transferred from Cautirina to Metriorrhynchina incertae sedis. The study clarifies the taxonomy of Metriorrhynchini and should serve as a restarting point for further taxonomic, evolutionary, and biogeographic studies.

Sign in / Sign up

Export Citation Format

Share Document