Archive

A comparative study of the ventral skeleton of idiosoma of male of the subfamily Amblyomminae was carried out. Much prominence was given to the hind half of idiosoma: great diversity of the composition, shape, size and topography of integumentary hard elements. A comparative study of the topography of dorsoventral musculature attachment to the ventral wall of idiosoma in its hind half was carried out, too. The structure of skeleton with the largest area and least differentiation, should be considered most primitive; in this case all hard elements have no distinct species or group form and are attached rigidly to the extensible cuticle. Such structure is characteristic of Haemaphysalis (Allocerea) inermis which has primary unpaired anal and paired postanal shields occupying nearly the whole ventral surface of the hind half of idiosoma (fig. 1, 1). This variant suggests the other ones characteristic of the subfamily Amblyomminae. Two types of evolutionary transformations of hard ventral integuments of male have been revealed. One type represents a successive process of skeleton reduction through disintegration of primary shields into numerous small ones and decrease of their sizes and number up to their complete disappearance (figs. 1, 2). Hard elements are preserved for the most long time on hind branches of the genital groove. Continuous chains of bundles of dorso-ventral musculature, running along hind branches of the genital groove, are attached to hard elements and reach the posterior end of idiosoma between scallops II and III (fig. 5). In H. (Allocerea) inermis muscles are attached to the primary paired postanal shields, and where a partial skeleton reduction took place — to derivatives of these shields. The shields or their derivatives have no species or group form, are asymmetrical and attached rigidly to extensible integuments; the number of derivative sclerites varies much. A complete reduction of the ventral skeleton marks the top of this evolutionary trend. In this case the topography of musculature attachment is preserved (fig. 5). During evolutionary transformations of the other type the primary postanal shields along the line of hind branches of the genital groove broke into adanal and accessory ones, and their medial and lateral divergence took place (figs. 3, 4). Later on, in some recent genera the skeleton underwent a partial reduction at the expense of the decrease of the above shields in area, or complete disappearance of the accessory ones (figs. 3, 2; 4—6). On the contrary, in the other genera the area of hard integuments enlarged on account of the growth or increase in the number of shields (fig. 4). If the transformations are estimated by the character of hard integuments area, then their initial stage is close to the area in H. (Allocerea) inermis (figs. 3, 1, 3). But this type of transformations lacks a complete reduction of ventral skeleton. The topography of attachment of the bundles of dorso-ventral musculature to the ventral wall of idiosoma is characterized by the branching from the genital groove to adanal and accessory shields and the bundles do not reach marginal scallops (fig. 6). All the shields have a distinct species or group form and number; the connection with extensible integuments is semimobile. The two types evolutionary transformations of the ventral skeleton of idiosoma in male with characteristic topography of musculature attachment enable us to place two tribes in the subfamily Amblyomminae Banks, 1907. The tribe Amblyommini Banks, 1907 includes the genera Haemaphysalis Koch, 1844, Amblyomma Koch, 1844, Aponomma Neum., 1899, Anomalohimalaya Hoog., Kaser et Mitch., 1970, Dermacentor Koch, 1844, Rhipicentor Nutt. et Warb., 1908. The tribe Rhipicephalini Banks, 1907 includes the genera Rhipicephalus Koch, 1844, Hyalomma Koch, 1844, Cosmiomma Schulze, 1919, Nosomma Schulze, 1919, Boophilus Cur., 1891, Margaropus Karsch., 1897.

Observations were made through examination of thin blood films which were prepared at appropriate intervals from citrated fresh blood of infected birds. The comparative description of gametogenesis, zygote and ookinete formation of Haemoproteus tartakovskyi, H. belopolskyi, H. fringillae, H. pallidus under the light microscope is given for the first time. This process has a general pattern for all investigated haemoproteid species. It is shown that macrogametocyte has been transformed directly to macrogamete without forming a residual body, as it was noted by Desser (1972) for H. (=Parahaemoproteus) velans. The most informative signs, which can be used for haemoproteid systematics, were determined. Among them microgamete length, zygote structure, morphological features of developing ookinete as well as the rate of ookinete formation can be pointed out first of all. H. pallidus microgametes are twice shorter than H. tartakovskyi, H. belopolskyi, H. fringillae ones. A large clear vacuole is formed in zygote of H. fringillae only. The majority of diagnostic features has the developing ookinetes. On the basis of ookinetes morphology the investigated species of haemoproteids can be determined easily. There were clear differences between haemoproteid species on the rate of ookinete formation. The ookinetes of H. belopolskyi and H. fringillae are formed for about 12 times more slowly than H. pallidus ones, and for about 6 times more rapidly than H. tartakovskyi ones. The peculiarities of gametogenesis, zygote and ookinete formation under the stable conditions in vitro can be used as usefull additional signs for determination of haemoproteid species.

The ultrastructure of Tuzetia coryniformis Voronin, 1968, a parasite of the copepode Macrocyclops albidus Jur., is described with emphasis on the sporophorous vesicle and mature spore. The sporogonial Plasmodium is divided by a rosette-like budding, producing 4 — 8 sporoblasts. Stages of sporogony are limited by a thin and fragile envelope of the sporophorous vesicle. The lageniform, 7—8.5 µm long uninucleate spores have a heterofilar polar filament arranged in 16 — 17 coils. The polaroplast consists of three lamellar parts. Young spores have the exosporal coat which is transformed into the individual episporal envelope in mature spores. On the basis of the ultrastructural cytology the microsporidium is transferred from the genus Tuzetia to the genus Cougourdella.

The diploid number of chromosomes of T. szidati and B. polonica equals 16. Karyotype structure of T. szidati is as follows: 1,5,8 m+2,6,7 sm+3 st-sm+sm-m, that of B. polonica is 1 Z st, 1 W sm+2,8 m+3,7 sm-m+4,6 sm+5 m-sm. The absolute length of chromosomes of T. szidati is from 3.41 to 8.71 µm, that of B. polonica from 2.48 to 9.48 µm. The relative length of Z chromosomes constitutes 23.26, W — 9.79% of the total haploid set length of B. polonica. It is noteworthy that the level of sex chromosomes differentiation is similar to that of the schistosomes of the genera Schistosomatium, Heterobilharzia and Austrobilharzia.

The ultrastructure of the scolex protonephridial system in five species of cestodes of the families Hymenolepididae, Dilepididae, Taeniidae is described. The following morphofunctional departments are distinguished: ciliary (flame) cells, the "weir", the terminal excretory canals, excretory canals. The epithelium of excretory canals is supposed to be a polyfunctional system like tegument. The "draining" of cestode body, the ensuring of the interstitial fluid current from the surface to the inner departments, is considered to be the main function of the excretory system along with the osmoregulation.

The structure of cysts of metacercariae of O. felineus has been analyzed. The cyst structure appears to have folds, pores and spherical formations providing for larval homeostasis. On the tegument of metacercariae thorns are arranged in staggered order. They represent 3 to 6 finger-shaped structures. The thorns and tegument excreta are secreted. On the surface of the parasite there are single and group sensory cupola-shaped and conoid papillae which make a chain around the mouth sucker. Polymorphism is revealed in the opisthorchis metacercariae structure.

Summary is absent.

Cladistic analysis of phylogenetic relations between species of the genus Cotylurus was carried out. The obtained data show that the genus is homogenous and monophyletic and serve as a basis for unification of the genera Cotylurus and Cotylurostrigea as the species assigned to the latter do not form a monophyletic branch. The same analysis of phylogenetic relations between the genera of the family Strigeidae has confirmed the validity of separation of the genus Pseudapatemon into a distinct subfamily. The other genera form two distinct monophyletic groups differing in the structure of copulatory organ. It seems to be expedient to accord the above groups the rank of subfamilies: Cotylurinae (the genera Cotylurus and Ichthyocotylurus) and Strigeinae (all the other genera excluding Pseudapatemon).

Larval material on the Aedes mosquitoes of the complex punctor (Far East expeditions in 1976—1980) was compared to material preserved in the Zoological Institute, Academy of Sciences of Russia. 6 types of aberrations (presence — absence of accessory hairs on the surface of siphon, their parity, etc.) were found. The individual variability and absence of diagnostic validity of these accessory hairs are suggested.

Data are compared on the intensity of immunity at the Oedemagena infection depending on the protein quantity in antigen and the intensity of infection of reindeer.

A new species of cestodes is described from the intestine of Erignathus barbatus Erx. The species differs from the other members of the genus in the shape of scolex, the character of strobilation and in many other characters. Data are given on its morphological variability in different waters: the Greenland and East-Siberian Seas, the Bering Strait. Two subspecies, D. s. europeum and D. s. asiaticum, are erected. The species is named in honour of Professor A.S. Scrjabin, one of the most outstanding workers in the field of helminthology of marine mammals.

Differences in the infection with copepods and the character of distribution of occurrence frequencies of Lernaea in crucian carp depending on the body length and sex of the latter are shown. The lowest infection rate with copepods was recorded for fishes with body length 8—11 cm as compared to specimens with body length 12—18 and 18.5—34 cm. The two latter groups did not differ from each other in this index. In males and females whose body length is 8—11 cm as well as in females with body length 12—34 cm the occurrence frequencies of Lernaea are satisfactorily described by the negative binominal distribution curve. In males with body length 12—18 cm the occurrence frequencies of copepods are approximated by the binominal distribution curve. On the basis of obtained data it was concluded that fishes with a small body length as well as Carassius males and females with a greater body length represent three distinct host groups which differ in their part of maintaining the number of Lernaea of the host group.