Morphometric variation of individuals in field collected samples of the Hyalopterus pruni complex from various Prunus species and regions of Greece was examined, to determine whether this variation is correlated with the host-trees from which the aphids originated. Morphometric data for 13 parameters of aphids from 74 field samples (760 adult apterae) were analysed by canonical variates analysis (CVA). Each sample was collected from a different tree and consisted of individuals from 2-3 neighbouring leaves from the same branch. Each field sample was used as a grouping factor in the CVA. The analysis produced three clusters corresponding to the taxa indicated by previous studies using allozyme markers (i.e., Hyalopterus pruni on apricot, blackthorn, plum and cherry, H. amygdali A on almond and H. amygdali B on peach). The separation was independent on the geographical origin of the samples. However, host associations within the complex were not absolute, and in particular the samples from apricot appeared to include both H. pruni and H. amygdali A. In contrast to previous views, the present study showed that the taxa have their own distinct morphology. Lastly, discriminant functions for separating the adult apterae of the taxa are given.
Tomicus piniperda and T. destruens are sibling species which are extremely difficult to separate by morphological characters. Although several papers report differences between the two species, many characters need confirmation or better description. Moreover, new morphological characters are required for correct species determination. For these purposes, eight populations of T. destruens from Italy, Greece, Spain and Algeria, and ten of T. piniperda from Finland, Poland, Czech Republic, Austria, Sweden and Italy, were investigated considering eleven morphological characters. The morphological differences most useful for the species separation include four previously described characters (colour of the elytra, colour of the antennal club, distribution of the antennal setae, distribution of the punctures along the elytral declivity), and four new characters (body proportions, setation of the first antennal club suture, sculpture of the elytral declivity and striae density of the pars stridens). Distribution of the two species is discussed and an illustrated key is included.
Brachylecithum microtesticulatum Timon-David, 1955 (Digenea: Dicrocoeliidae) is recorded for the first time in the Black Sea region. The morphology and variability of the digeneans recovered from Larus argentatus in Bulgaria and the Ukraine are described and compared with the redescription of the species (Bartoli and Mas-Coma 1989). Lyperosomum lari Travassos, 1917 of Smogorzhevskaya (1976) is considered a synonym of B. microtesticulatum.
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.
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.
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.
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.
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.")
Adult females of Strongyloides robustus Chandler, 1942, a parasite of sciurids in North America, were found in the duodenal mucosa of 30 of 32 red squirrels (Tamiasciurus hudsonicus (Erxleben)) collected in Cape Breton Island, Nova Scotia, Canada. The parasitic female is illustrated and redescribed; characteristics include: body 3.8-8.0 mm long, cephalic extremity with X-shaped mouth and 8 circumoral lobes, ovaries spiralling around intestine, and tail bluntly rounded. Eggs in fresh feces contained tadpole-stage larvae. In fecal cultures, eggs hatched and larvae invariably developed to the filariform infective third stage; i.e. a free-living generation did not occur and is probably absent in S. robustus in Cape Breton and possibly other parts of North America. It is hypothesized that homogonically developing S. robustus might be more fecund or more efficiently transmitted than species of Strongyloides that exhibit both homogonic and heterogonic development. Larvae of S. robustus in fecal cultures, i.e. homogonic larvae, are described in detail. Intestinal walls of second- and third-stage larvae, as well as the lateral chords of young third-stage larvae, contained numerous round bodies, likely nutrient stores. Third-stage larvae were present within 2 days in cultures maintained at 30°C, 4 days at 20°C, and 7 days at 15°C. They lived for at least 33 and 30 days at 15° and 20"C, respectively. Third-stage larvae probably die when their nutrient stores are exhausted.
A new genus Diphyonyx is proposed here for a previously unrecognised lineage of geophilid centipedes. It is distinct from other geophilids in its unique combination of morphological characters, including the peculiar shape of the pretarsus of the legs on the anterior part of the trunk. The type species D. conjungens (Verhoeff, 1898), comb. n., is redescribed in detail and its geographical distribution updated (Balkan Peninsula, Anatolia, Crimea). Included in Diphyonyx are also D. sukacevi (Folkmanová, 1956), comb. n., and D. garutti (Folkmanová & Dobroruka, 1960), comb. n., both from southern Russia. D. garutti is raised here to species rank.