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39992. Morphology and ultrastructure of the male reproductive system of the woolly beech aphid Phyllaphis fagi (Hemiptera: Aphididae: Phyllaphidinae)
- Creator:
- Wieczorek, Karina and Świątek, Piotr
- Type:
- article, model:article, and TEXT
- Subject:
- Aphididae, Phyllaphidinae, Phyllaphis fagi, male reproductive system, and ultrastructure
- Language:
- English
- Description:
- In the present paper we describe for the first time the ultrastructure of the male reproductive system of aphids using Phyllaphis fagi as a representative. Paired testes of this species consist of three follicles each, arranged in a rosette, the walls of the proximal part of vasa deferentia cling together, accessory glands are club-shaped and elongated whereas the ejaculatory duct is reduced. Our study also shows that vasa deferentia, accessory glands and ejaculatory duct are histologically very simple. All of them are composed of cubical epithelium of secretory type. The epithelial cells are rich in rough endoplasmic reticulum, Golgi complexes and produce small heterogeneous vacuoles. The apical membrane of these cells forms microvilli. The reproductive system epithelia stand on thin basal lamina. Outside the basal lamina thin muscle fibres are observed. Histochemical staining shows that secretion filling the lumen of vasa deferentia and accessory glands contains proteins and polysaccharides.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39993. Morphology of accessory ovaries in adult males of Perla marginata (Plecoptera: Perlidae)
- Creator:
- Rościszewska, Elźbieta and Soldán, Tomáš
- Type:
- article, model:article, and TEXT
- Subject:
- Plecoptera, Perla, Dinocras, rudimentary hermaphroditism, morphology, ultrastructure, accessory ovary, vitellogenesis, follicular epithelium, and sex determination
- Language:
- English
- Description:
- Bisexual gonads in the stoneflies Perla burimeisteriana, P. pallida and Dinocras cephalotes are reported for the first time. Gross morphology and ultrastructure of the accessory ovaries of mature larvae and adult males of Perla marginata are described in detail. There are 36-58 male ovarioles situated distal to the paired testes and opening into fused termini of the lateral ducts in abdominal segments II and III. These correspond in structure to the ovarioles of adult females but are significantly smaller (maximum size of proximal oocyte 9.0 × 45 µm) and each usually contains 10-14 linearly arranged previtellogenic oocytes. Oogenesis ceases at the end of previtellogenesis or at the onset of vitellogenesis. The ooplasm contains either regularly dispersed or irregularly accumulated particles in different regions of the cell with accumulations occurring near mitochondria and Golgi complexes. Based on results of metachromatic staining, these are thought to represent either lipid droplets (most) or yolk globules. The oolemma rarely develops short microvili and few pycnotic vesicles. Development of the follicular epithelium (influencing vitellogenesis and secretory activity during choriogenesis) is abnormal. Follicular cell growth is not synchronized with that of the oocytes, and the follicular cells of the terminal (distal) oocytes show neither patency nor secretory activity. The mechanism controlling degeneration of male ovarioles and the evolutionary significance of hermaphroditic gonads in the Plecoptera are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39994. Morphology of Bertiella studeri (Blanchard, 1891) sensu Stunkard (1940) (Cestoda: Anoplocephalidae) of human origin and a proposal of criteria for the specific diagnosis of bertiellosis
- Creator:
- Galán-Puchades, Maria Teresa, Fuentes, Márius Vicent, and Mas-Coma, Santiago
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Bertiella studeri, diagnosis of bertiellosis, species complex, and morphology
- Language:
- English
- Description:
- Human material of an African specimen of Bertiella studeri (Blanchard, 1891 ), a typical intestinal ceslode of monkeys, is described. Mature, postmaturc and gravid proglottides, and eggs, previously inadequately figured, are illustrated and photographed. The description of the species agrees with that provided by Stunkard (1940). A comparative study with other descriptions of the species is made in an attempt to clarify previous findings. The morphological differences reported in various earlier descriptions of the species suggest that B. studeri should be regarded as a “B. studeri species complex”. Improvements are required in the descriptions of new future findings in order to clarify the specific diagnosis of human bertiellosis. Evidence suggests that a generalised diagnosis exclusively based on egg size and geographical distribution is insufficient to differentiate B. studeri and Bertiella mucronata (Meyner, 1895), or additional species may be affecting humans.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
39995. Morphology of immature stages of Prostomis mandibularis (Coleoptera: Tenebrionoidea: Prostomidae)
- Creator:
- Schunger, Isabel, Beutel, Rolf G., and Britz, Ralf
- Type:
- article, model:article, and TEXT
- Subject:
- Prostomis mandibularis, Prostomidae, Tenebrionoidea, SEM, morphology, larva, pupa, larval head anatomy, and systematic position
- Language:
- English
- Description:
- Structural features of larvae and pupae of Prostomis mandibularis are described in detail. Larval features are discussed with respect to their functional and phylogenetic significance. The distinct asymmetry of the larval head, absence of stemmata, presence of a sensorial field on antennomere III, and elongated and broadened mandibles of pupae and adults are autapomorphies of Prostomidae. The placement of Prostomis within Tenebrionoidea is suggested by the posteriorly diverging gula with well developed gular ridges and the anterior position of the posterior tentorial arms. Affinities of Prostomidae with the pythid-pyrochroid-lineage is supported by the pad-like structure of the maxillary articulatory area, the abdominal tergite IX extending to the ventral side of the segment, and the strongly pronounced prognathous condition. Presence of a distinct molar tooth is a derived feature shared by Prostomidae, Pythidae, Pyrochroidae, Inopeplidae and Othniidae. A thorax narrower than the head and the abdomen, and a plate-like abdominal segment IX, which articulates with segment VIII, are possible synapomorphies of Prostomidae, Boridae, Mycteridae and Pyrochroidae. The strongly flattened, prognathous head and the strongly flattened body of larvae of Prostomidae are correlated with their habits of boring in wood of decaying logs.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39996. Morphology of invasion: body size patterns associated with establishment of Coccinella septempunctata (Coleoptera: Coccinellidae) in western North America
- Creator:
- Evans, Edward W.
- Type:
- article, model:article, and TEXT
- Subject:
- biological control, biological invasions, body size, Coccinella septempunctata, Coccinella transversoguttata, Coccinellidae, exotic species, Hippodamia convergens, Hippodamia quinquesignata, Hippodamia sinuata, Hippodamia tredecimpunctata, habitat distribution, interspecific competition, intraguild predation, and invasive species
- Language:
- English
- Description:
- The Old World ladybird Coccinella septempunctata has rapidly established itself as an abundant, widespread species throughout North America. Overwintering individuals of this species, and of native ladybirds, were collected from early season alfalfa in northern Utah during the period of initial establishment of the invader (1989 to 1999), and were measured for body size. Adult body size can vary widely within insect species, often reflecting differential success of individuals as immatures in obtaining food. Here I examine patterns of ladybird body size to address two questions associated with the establishment of C. septempunctata: (1) is there evidence for adverse impact on native species?, and (2) why has the invader has been so successful in establishment? As an indirect test of adverse competitive effect of the invader on native species, I determined whether mean body size of adults of the five most common native species (Coccinella tranversoguttata, Hippodamia convergens, H. quinquesignata, H. sinuata, and H. tredecimpunctata) declined over the period 1991-1997 as the invader increased rapidly in abundance. No such decline was observed for any of these species, thus providing no evidence that the invader's establishment has significantly increased scramble competition for food among immature ladybirds. I also compared body size distribution of the invading species with that of native species. The invader was distinctive in having particularly large variation in body size among individuals (i.e., in having relatively high proportions of both unusually large and small individuals). Such results are consistent with the hypothesis that the invader's success derives from being a generalist with much "ecological flexibility" in regard to the conditions under which it engages and succeeds in reproduction.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39997. Morphology of the karyologically identified spined loach (Teleostei, Cobitidae) from a diploid population
- Creator:
- Jeleń, Iwona, Boroń, Alicja, Szlachciak, Jolanta, and Juchno, Dorota
- Type:
- article and TEXT
- Subject:
- diploids, Cobitis taenia, morphology, osteology, and taxonomy
- Language:
- English
- Description:
- The variability of morphological characters was studied in a population of spined loach from Klawój Lake karyologically identified as a pure diploid C. taenia (2n = 48). 24 metric features were used to calculate correlation coefficients and linear regressions to determine the relationships between metric features with total length. As regards 11 meristic features, females had more lateral and predorsal spots than males. Statistically significant differences between males and females were also found in mean values of 15 metric indices. Age variability in the shape of the lamina circularis of males was revealed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
39998. Morphology of the spermatheca in the Cydnidae (Hemiptera: Heteroptera): Bearing of its diversity on classification and phylogeny
- Creator:
- Pluot-Sigwalt, Dominique and Lis, Jerzy A.
- Type:
- article, model:article, and TEXT
- Subject:
- Heteroptera, Pentatomomorpha, Pentatomoidea, Cydnidae, Amaurocorinae stat. n., vaginal structures, spermatheca, parietovaginal gland, ring sclerite, fecundation canal, morphology, classification, and phylogeny
- Language:
- English
- Description:
- Cuticular parts of the spermatheca and associated vaginal structures (chiefly the ring sclerites of the parietovaginal glands) have been examined and compared in 190 cydnid species representing 65 genera and all five subfamilies currently recognized in the family (Amnestinae, Cephalocteinae, Cydninae, Garsauriinae, Sehirinae). Four species belonging to genera formerly included within the Cydnidae (Dismegistus, Parastrachia, Thaumastella, Thyreocoris) were also examined. Morphology of the three main parts of the spermatheca [seminal receptacle (distal bulb), intermediate part (pump apparatus), spermathecal duct] is described. Four main types of spermathecae can be recognized from the distal receptacle and the intermediate part: the amaurocorine type (in Sehirinae: Amaurocorini), amnestine type (in Amnestinae), garsauriine type (in Garsauriinae), and "cydnoid" type (in Cephalocteinae + Cydninae: Cydnini, Geotomini + Sehirinae: Sehirini). No synapomorphy of these types was found which suggests that the currently conceived Cydnidae are not monophyletic. Moreover, out of these four types only the "cydnoid" is typically pentatomoidean due to the presence of an intermediate part usually well delimited by two flanges and having always an unsclerotized flexible zone as well as two internal cuticular structures (septum and fretum) partly obstructing the lumen. The simple tubular amaurocorine type is unusual and aberrant within all Pentatomoidea. The amnestine and garsauriine types display some similarities with taxa outside the Pentatomoidea, especially with some lygaeoid or coreoid spermathecae, mainly in the structure of the intermediate part not delimited proximally (absence of flanges) and devoid of the flexible zone. Within the "cydnoid" type, six spermathecal facies can be characterized principally according to the shape of both the apical reservoir along with the intermediate part, and the differentiations of the spermathecal duct. It has been impossible to find any synapomorphy for all species and for the six facies belonging to the "cydnoid" type of spermatheca. We suggest that the Cydnidae as defined presently are probably a polyphyletic group; moreover its main "cydnoid" branch, called by us Cydnidae sensu stricto (Cephalocteinae + Cydninae + Sehirinae: Sehirini) seems to be relatively recent among the Pentatomoidea. Nishadana and Nishocoris are transferred from Garsauriinae back to Cydninae: Cydnini and the tribe Amaurocorini (Sehirinae) is upgraded to a separate subfamily Amaurocorinae stat. nov. Moreover, we regard the Geotomini and the Sehirini both as non-monophyletic and we indicate that by appending them sensu lato (Geotomini "s. l.", Sehirini "s. l.")
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
39999. Morphology, bioacoustics and phylogeography of the Isophya major group (Orthoptera: Tettigoniidae: Phaneropterinae): A species complex occurring in Anatolia and Cyprus
- Creator:
- Sevgili, Hasan, Ciplak, Battal , Heller, Klaus Gerhard , and Demirsoy, Ali
- Type:
- article, model:article, and TEXT
- Subject:
- Orthoptera, Phaneropterinae, Isophya, I. major, I. mavromoustakisi, I. mersinensis sp. n., I. salmani sp. n., biogeography, Anatolia, Cyprus, Turkey, and Eastern Mediterranean
- Language:
- English
- Description:
- The species of the Isophya major-group (Orthoptera: Tettigoniidae: Phaneropterinae), are reviewed. I. major Brunner von Wattenwyl and I. mavromoustakisi Uvarov are redescribed. Two new species are described; Isophya mersinensis Sevgili & Çiplak sp. n. and Isophya salmani Sevgili & Heller sp. n. from south Anatolia. Illustrations of morphology and male calling song are provided and a detailed comparison of the four species in the group is presented. We conclude that these four species constitute a natural group in sharing male cerci with two or more denticles not ordered in a line, a character unique to this species group within the genus. From an evaluation of their morphology and song characteristics, relationships among the species in the group are I. major + (I. mersinensis sp. n. + (I. salmani + I. mavromoustakisi). Based on the the distribution pattern and habitat preference, we concluded that the division of I. salmani and I. mavromoustakisi was a vicariant event resulting from the separation of Cyprus and Anatolia due to reflooding of the Mediterranean after the Messinian salinity crisis at the beginning of the Pliocene, around 5 My ago.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
40000. Morphology, cytology and sexual reproduction in the aerophytic cave diatom Luticola dismutica (Bacillariophyceae
- Creator:
- Poulíčková, Aloisie
- Type:
- article and TEXT
- Subject:
- auxosporulation, diatoms, homothally, meiosis, and sexual reproduction
- Language:
- English
- Description:
- Monoclonal cultures of the aerophytic cave diatom Luticola dismutica were studied and its frustule morphology, cytology and reproduction recorded. Luticola dismutica is a laterally asymmetrical, monoplastidic pennate diatom with imposed chloroplast division and nuclear behaviour of type 1.A sensu Mann & Stickle. Clones of L. dismutica decreased in cell size in culture until they have reached the sexual size range. Homothallic sexual reproduction and auxosporulation (type IB1a auxosporulation sensu Geitler) were induced in four sexualized clones. Gametangia paired via the girdle, two isogametes were formed per gametangium and hence two zygotes were produced per pair of gametangia. No surviving superfluous nuclei were observed in the gamete and zygote stages and no unfused haploid nuclei were seen in the auxospore stage; zygotes and expanded auxospores had only one nucleus. Auxospores expanded perpendicular to the apical axis of gametangia. Expanded auxospores and initial cells had a swollen central part, the linear-lanceolate outline shape of the vegetative valves was restored during the first divisions of the post-initial cells. Initial cells left the perizonium by a route unique to pennate diatoms, through a transverse rupture of the perizonium. The key cytological and reproductive characteristics reviewed in this paper indicate, that Luticola is more closely related to Placoneis and Dickieia, than to Navicula sensu stricto.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/