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1

Philotolepis raymondi [Gigon et Beuret, 1991] comb.n. [Cyclophyllidea, Dilepididae]: new geographical record and synonymy

100%
Georgiev B. B., Genov T.
Acta Parasitologica
|
1993
|
tom 38
|
nr 3
Ptilotolepis raymondi (Gigon et Beuret, 1991) comb. n. (Syns. Unciunia raymondi Gigon et Beuret, 1991; Ptilotolepis philomelae Okulewicz, 1991, new synonymy) is recorded and redescribed from Turdus philomelos (Passeriformes, Muscicapidae, Turdinae) in Bulgaria. The same specimens were mentioned as Anomotaenia constricta by Paspalev and Paspaleva 1972 and as Ptilotolepis sp. by Georgiev 1990. P. raymondi is regarded as a species specific parasite of T. philomelos.
2

The morphology and new records of two progynotaeniid cestode species

100%
Nikolov P. N., Georgiev B. B.
Acta Parasitologica
|
2002
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tom 47
|
nr 2
Progynotaenia odhneri Nybelin, 1914 and Paraprogynotaenia charadrii (Yamaguti, 1956) are redescribed and figured on the basis of specimens from Charadrius alexandrinus in Bulgaria (new geographical records). P. odhneri of Ryzhikov and Tolkacheva (1981) is considered to represent a heterogeneous group of species. The allocation of P. charadrii to the genus Paraprogynotaenia rather than Proterogynotaenia, as proposed by Jensen etal. (1983), is confirmed. The regularity of the alternation of the genital pores is rejected as a character for distinguishing Progynotaenia and Paraprogynotaenia; for this purpose, (he most reliable character is the position of the seminal receptacle relative to the ovary in female proglottides.
3

Redescription of Decorataria decorata [Spirurida, Acuariidae] based on nematodes from Podiceps cristatus and P.grisegena [Aves, Podicipediformes] from Bulgaria

100%
Mutafchiev Y., Georgiev B. B.
Acta Parasitologica
|
2008
|
tom 53
|
nr 2
Decorataria decorata (Cram, 1927) is redescribed on the basis of light-microscopy and SEM observations on specimens collected from the stomach of Podiceps cristatus and P. grisegena from Bulgaria. The SEM study revealed the presence of a porebearing field on each pseudolabium and a pair of spines (one dorsal and one ventral) situated between bases of the cordons. The deirids are spine-like and minute. The light-microscopy examination showed the presence of ornamentation situated under the dorsal surface of caudal alae. The occurrence of D. decorata in Bulgaria is a new geographical record.
4

First record of the nematode Aviculariella alcedonis [Yamaguti et Mitunaga, 1943] [Spirurida, Acuariidae] in Europe, with SEM observations and comments on its taxonomic position

81%
Mutafchiev Y., Zehtindjiev P., Georgiev B. B.
Acta Parasitologica
|
2009
|
tom 54
|
nr 4
374-379
Aviculariella alcedonis (Spirurida, Acuariidae) is recorded from Alcedo atthis (Coraciiformes, Alcedinidae) from Bulgaria (new geographical record). A description of female specimens based on light-microscopy and SEM studies is presented. On the basis of the observations of the cephalic end, the position of the genus is considered to be in the subfamily Acuariinae, not in the Seuratiinae where it was previously placed. The host range of Aviculariella spp. is recognised as restricted to birds of the family Alcedinidae. A new morphological peculiarity described in A. alcedonis is the presence of a pair of sublateral ribs at the anterior end of each pseudolabium.
5

A new genus of the family Hymenolepididae (Cestoda) from Sephanoides sephaniodes (Apodiformes, Trochilidae) in Northern Patagonia (Chile)

81%
Widmer V. C., Georgiev B. B., Mariaux J.
Acta Parasitologica
|
2013
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tom 58
|
nr 1
A new species of hymenolepidid cestodes from Sephanoides sephaniodes (Trochilidae) found in Chile is described. The most characteristic features of Colibrilepis pusilla gen. nov., sp. nov. are the lack of rostellum, a cirrus sac with a thick-walled distal end (separated by a constriction) and protruding into genital atrium, a thick-walled saccular uterus filling entire median field of the gravid proglottis and the small number of eggs containing thick walled embryophores with polar swellings. Staphylepis is the most similar genus but differs in its apical structure because of the presence of a rudimentary rostellum. Moreover, molecular phylogenetic analyses show that Staphylepis and Colibrilepis are not sister taxa.
6

Redescriptions and comments on the validity of Acuaria subula and A. skrjabini (Nematoda, Spirurida, Acuariidae), parasites of passerine birds

81%
Mutafchiev Y., Kontrimavichus V. L., Georgiev B. B.
Acta Parasitologica
|
2013
|
tom 58
|
nr 3
Acuaria subula (Dujardin, 1845) is redescribed by light microcopy (LM) and scanning electron microscopy (SEM) on the basis of specimens from its type host, Erithacus rubecula (Passeriformes, Muscicapidae), from Curonian Spit (Kaliningradskaya Oblast’, Russia) and Bulgaria. Acuaria skrjabini (Ozerskaya, 1926) is redescribed by LM and SEM on the basis of specimens from Passer domesticus (type host) and P. hispaniolensis (Passeriformes, Passeridae) from Bulgaria. Contrary to previous opinions recognizing A. skrjabini as a junior synonym of A. subula, the present study confirms that they are distinct species. They can be distinguished on the basis of the ratio between the length of cordons and the body length, the ratio between the length of muscular oesophagus and glandular oesophagus, and the ratio between the total length of oesophagus and the body length. In addition, the plates forming the cordons in these two species exhibit different morphological characters. Another difference between these two species is associated with the particular irregular mosaic ornamentation of the cuticle on the ventral and lateral sides of body around the region of vulva of A. subula and its absence in A. skrjabini. Data on their host and geographical ranges are surveyed. The type series of Acuaria buttnerae Chabaud et Petter, 1961, described as a parasite of Calandrella brachydactyla (Passeriformes, Alaudidae) in France, is re-examined; the latter species is recognized as a junior synonym of A. skrjabini (new synonymy).
7

Land snails in the transmission of protostrongylids on pastures in Southern Bulgaria: variability of infection levels related to environmental factors

81%
Georgiev D. M., Kostadinova A., Georgiev B. B.
Acta Parasitologica
|
2003
|
tom 48
|
nr 3
Prevalence, intensity and abundance of protostrongylid larvae in snails and slugs were studied on 10 sheep and goat pastures in the region of Stara Zagora, Southern Bulgaria, in 2001. Eight gastropod species were infected: Helicella obvia, Cernuella virgata, Monacha cartusiana, Zebrina detrita, Cepaea vindobonensis, Chondrula microtraga, Helix pomatia and Deroceras reticulatum. Four nematode species were identified: Muellerius capillaris, Neostrongylus linearis, Cystocaulus ocreatus and Protostrongylus sp. Helicella obvia was the most common and abundant snail, and showed the highest infection parameters. Cernuella virgata was the only species in one pasture and had high infection descriptors. Monacha cartusiana and Zebrina detrita had high infection levels in some pastures. A subset of data representing the infection of H. obvia was used to test for relationships with environmental characteristics. Protostrongylid infections in this host species showed considerable variation between sites. M. capillaris had the highest prevalence and intensity, followed by C. ocreatus and Protostrongylus sp. Comparisons of sites at lower vs at upper elevations did not show significant differences in infection, with the exception of Protostrongylus sp. The primary vegetation was the only explanatory variable for the total prevalence of protostrongylids. This variable, in a combination with altitude, mollusc species richness and sample size explained 73% of the variation of mean intensity. In the models explaining variations in the prevalence and the mean intensity of the nematode species, 9 variables were included: primary vegetation, altitude, annual precipitation, mean annual precipitation, mollusc and nematode species richness, concentration of inorganic nitrogen in soil, snail population density and ratio between the number of goats and the number of sheep grazing on pasture. H. obvia was considered a suitable screening species for assessing the pasture contamination in the region.
8

Cyclophyllidean cysticercoids from Echinogammarus tibaldii [Amphipoda, Gammaridae] from Lake Piediluco, Italy

81%
Nikolov P. N., Georgiev B. B., Dezfuli B. S.
Acta Parasitologica
|
2008
|
tom 53
|
nr 2
In August 2007, 856 specimens of Echinogammarus tibaldii Pinkster et Stock, 1970 from the Lake Piediluco (Central Italy) were collected from 3 different sites and examined for larval helminths. Fourteen amphipods (1.63%) were infected with larvae of Lateriporus teres (Dilepididae) and one amphipod (0.12%) was infected with Microsomacanthus microsoma (Hymenolepididae). Adults of both species are known from waterfowl and gulls. The present results constitute new host records for both cestode species and the first finding of L. teres in Italy.
9

Ultrastructure of spermiogenesis and mature spermatozoon of Skrjabinoporus merops [Cyclophyllidea, Metadilepididae]

71%
Yoneva A., Georgieva K., Mizinska Y., Georgiev B. B., Stoitsova S. R.
Acta Parasitologica
|
2006
|
tom 51
|
nr 3
The ultrastructure of the mature spermatozoon and the spermiogenesis of a cestode belonging to the family Metadilepididae is described for the first time. The mature spermatozoon of Skrjabinoporus merops is characterized by twisted peripheral microtubules, the presence of a single crested body, periaxonemal sheath and electron-dense rods, and the absence of intracytoplasmic walls and inclusions (glycogen or proteinaceous granules); no peripheral microtubules where nucleus contacts the external plasma membrane. Four morphologically distinct regions of the mature spermatozoon are differentiated. The proximal part (Region I) contains a single crested body, periaxonemal sheath is absent in some (proximal) sections and is present in others situated closer to the nucleus. The central Region II is nucleated, and is followed by Region III that contains a periaxonemal sheath. The distal pole, Region IV, is characterized by disintegration of the axoneme. Spermiogenesis follows the type III pattern (Bâ and Marchand 1995) although in S. merops a slight flagellar rotation is observed. The differentiation zone is characterized by the absence of striated roots and intercentriolar body; two centrioles are present, one of which gives rise to a free flagellum. The latter rotates and undergoes proximodistal fusion with the cytoplasmic protrusion of the differentiation zone. Spermiological characters of S. merops are similar to those of the families Taeniidae and Catenotaeniidae. The mature spermatozoon differs from those of the Dilepididae (where the metadilepidid species have previously been classified) by the lack of glycogen.
10

Records of cysticercoids of Fimbriarioides tadornae Maksimova, 1976 and Branchiopodataenia gvozdevi [Maksimova, 1988] [Cyclophyllidea, Hymenolepididae] from brine shrimps at the Mediterranean coasts of Spain and France, with a key to cestodes from Artemia spp. from the Western Mediterranean

61%
Vasileva G. P., Redon S., Amat F., Nikolov P. N., Sanchez M. I., Lenormand T., Georgiev B. B.
Acta Parasitologica
|
2009
|
tom 54
|
nr 2
143-150
Cysticercoids of two cestode species isolated from brine shrimps from the Mediterranean coasts of Spain and France are described. Fimbriarioides tadornae Maksimova, 1976 (adults known as parasites of Tadorna tadorna) was recorded from Artemia parthenogenetica and A. franciscana from Spain (Bras del Port and River Ebro Delta, respectively), and from A. franciscana from Aigues-Mortes, France (new geographical record). Branchiopodataenia gvozdevi (Maksimova, 1988) (adults known as parasites of Larus genei) was recorded from A. parthenogenetica (Bras del Port, Spain), A. salina (San Pedro del Pinatar, Spain) and A. franciscana (River Ebro Delta, Spain); this is the first record of the species in Europe. An illustrated key to cysticercoids of 12 cestode species from Artemia spp. from the Western Mediterranean is proposed.
11

Post-embryonic development and ultrastructural characteristics of the polycephalic larva of Taenia parva Baer, 1926 [Cyclophyllidea, Taeniidae]

61%
Swiderski Z., Miquel J., Mlocicki D., Georgiev B. B., Eira C., Grytner-Ziecina B., Feliu C.
Acta Parasitologica
|
2007
|
tom 52
|
nr 1
Post-embryonic development and fully-formed polycephalic larvae of Taenia parva Baer, 1926 were examined by light (LM) and transmission electron microscopy (TEM). Three developmental stages were recognised: (1) an early stage of exogenous budding at the surface of the central vesicle; (2) a stage of polycephalic cyst development accompanied by segmentation of the growing larval strobile and an obvious decrease in the size of the central vesicle; (3) fully-formed larval strobile and invaginated scoleces. In fully-developed encysted polycephalic larvae, there are usually 14–24 segmented larval strobilae, each terminating with an invaginated scolex; larval strobilae arise from a common central vesicle and remain attached posterior to it during the entire development. The number of segments varies between 109 and 120 per larval strobila. The polycephalic larvae examined closely resemble the strobilocercus type of taeniid larvae. The structure of developing and fully-formed larvae was examined by TEM. The tegument, scolex, subtegumental musculature of the strobilar segments, protonephridial system, calcareous corpuscles and medullary parenchyma of larvae exhibit general similarity with the same structures in adults at both LM and TEM levels. The morphogenesis of the larva of T. parva is compared with that of the polycephalic larvae of other Taenia spp. (T. krepkogorski, T. twitchelli and T. endothoracica) and with other asexually-multiplying cestode larvae (mesocestoidids, hymenolepidids and dilepidids).
12

Ultrastructure of spermiogenesis and mature spermatozoon of Angularella beema [Clerc, 1906] [Cestoda, Cyclophyllidea, Delepididae]

61%
Yoneva A., Miquel J., Swiderski Z., Georgieva K., Mizinska Y., Georgiev B. B.
Acta Parasitologica
|
2006
|
tom 51
|
nr 4
The ultrastructure of the spermiogenesis of a dilepidid cestode species is described for the first time. The spermiogenesis of Angularella beema is characterised by absence of both flagellar rotation and proximodistal fusion. The differentiation zone is surrounded by cortical microtubules and is delimited by a ring of arching membranes. It contains two centrioles, one of which develops the axoneme that grows directly into the elongating cytoplasmic protrusion. This pattern of spermiogenesis was described as the Type IV spermiogenesis of cestodes. Among cestodes, similar pattern of spermiogenesis is known in the family Hymenolepididae and in some representatives of the family Anoplocephalidae. The mature spermatozoon of A. beema consists of five regions differing in their ultrastructural characteristics. It is characterised by the presence of cortical microtubules (spirally arranged at angle of 30–40° to the spermatozoon axis) and a single crested body. There is a periaxonemal sheath in certain parts of the spermatozoon as well as glycogen-like granules between the periaxonemal sheath and the cortical microtubules. The comparisons of the mature spermatozoon of A. beema with those of other two dilepidid species (Dilepis undula and Molluscotaenia crassiscolex) demonstrate some variation within the family: presence of periaxonemal sheath in A. beema and D. undula and its absence in M. crassiscolex; presence of electron-dense rods in D. undula and their absence in A. beema.
13

Cestodes from Artemia parthenogenetica [Crustacea, Branchiopoda] in the Odiel Marshes, Spain: A systematic survey of cysticercoids

61%
Georgiev B. B., Sanchez M. I., Green A. J., Nikolov P. N., Vasileva G. P., Mavrodieva R. S.
Acta Parasitologica
|
2005
|
tom 50
|
nr 2
A total of 3,300 specimens of brine shrimps Artemia parthenogenetica from the Odiel Marshes, Huelva Province, SW Spain, were studied during several seasons of 2002 and 2003 for the presence of cestode infections. Cysticercoids were found in 26.8% of brine shrimps. Eight cestode species were recorded, i.e., Hymenolepididae: Flamingolepis liguloides (adults parasitic in flamingos) with prevalence (P) 18.5%, mean intensity (MI) 1.48 and mean abundance (MA) 0.28; F. flamingo (adults parasitic in flamingos), P 0.9%, MI 1.03, MA 0.01; Confluaria podicipina (adults parasitic in grebes), P 6.5%, MI 1.42, MA 0.09; Wardium stellorae (adults parasitic in gulls), P 0.2%, MI 1.00, MA 0.002; Dilepididae: Eurycestus avoceti (adults parasitic in waders and flamingos), P 2.7%, MI 1.08, MA 0.03; Anomotaenia sp., probably A microphallos (adults parasitic in waders), P 0.8%, MI 1.04, MA 0.01; A tringae (adults parasitic in waders), P 2.2%, MI 1.01, MA 0.02; Progynotaeniidae: Gynandrotaenia stammen (adults parasitic in flamingos), P 0.6%, MI 1.00, MA 0.01. The cysticercoids are described and accompanying illustrations are presented. This study provides the first record of Anomotaenia tringae in an intermediate host and the first records of C. podicipina, E. avoceti, A. tringae and G. stammeri in Spain.
14

Larval helminths in the invasive American brine shrimp Artemia franciscana throughout its annual cycle

51%
Georgiev B. B., Angelov A., Vasileva G. P., Sanchez M. I., Hortas F., Mutafchiev Y., Pankov P., Green A. J.
Acta Parasitologica
|
2014
|
tom 59
|
nr 3
One of the best examples of rapid displacement of native species by an invader is the eradication of native Artemia salina and A. parthenogenetica in the Mediterranean by the introduced American A. franciscana. Previous studies based on sampling from limited time periods suggest that the success of the American species as a competitor may be due partly to different parasite burden, since native Artemia spp. have high cestode infection rates regulating their density. The aim of this study is to test the hypothesis that the helminth infection in A. franciscana in its invasive range is low throughout its annual life cycle. Samples of A. franciscana were collected every second month from La Tapa saltern (Andalusia) during one year. Five helminth species were recorded: cestodes Flamingolepis liguloides, F. flamingo, Gynandrotaenia stammeri (all flamingo parasites), Eurycestus avoceti (a shorebird parasite) and larval spirurids of the Acuariinae (the first record of nematodes in Artemia). The overall infection rate was low, with total prevalence 5.9% and prevalence of individual parasite species between 0.2 and 3.2%. The mean abundance of helminths was 0.005–0.155 (av. 0.068), 5–13 times lower than in native congeners. Waterbird counts indicate that the low infection rates cannot be explained by lack of definitive hosts. The results are consistent with the hypothesis that helminths have no regulating effect on the invasive brine shrimp in the Mediterranean. The replacement of the native populations by the invader can be partially explained by a competition mediated by parasites/predators through a differential impact on host fitness.
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