For a finite group $G$ denote by $N(G)$ the set of conjugacy class sizes of $G$. In 1980s, J. G. Thompson posed the following conjecture: If $L$ is a finite nonabelian simple group, $G$ is a finite group with trivial center and $N(G) = N(L)$, then $G\cong L$. We prove this conjecture for an infinite class of simple groups. Let $p$ be an odd prime. We show that every finite group $G$ with the property $Z(G)=1$ and $N(G) = N(A_i)$ is necessarily isomorphic to $A_i$, where $i\in\{2p,2p+1\}$., Azam Babai, Ali Mahmoudifar., and Obsahuje bibliografii
The external morphology of Aphylidae was studied previously in detail by the two junior authors, including the description of unique derived structures formed by their lateral thoracico-abdominal region (the exponium). Here we provide an additional description of the external scent efferent system of the metathoracic scent glands of species in the genus Aphylum Bergroth, 1906 (based on scanning electron microscope study) and its connection with an autapomorphic aphylid thoracico-abdominal region, the exponium. The origins of exponial sclerites are discussed and function of the exponium is hypothesised as being part of a complex defensive mechanism in the Aphylidae., Petr Kment, Pavel Štys, Jitka Vilímová., and Obsahuje seznam literatury
a1_Three genera of rhinebothriideans, previously referred to as New genus 1, New genus 2 and New genus 4, are erected in the the Anthocephaliidae. New genus 1 is established as Divaricobothrium gen. n., with Divaricobothrium tribelum sp. n. as its type species; Echeneibothrium trifidum Shipley et Hornell, 1906 is transferred to the genus as Divaricobothrium trifidum (Shipley et Hornell, 1906) comb. n. This genus is unique among rhinebothriidean genera in bearing bothridia that are posteriorly deeply divided into two lobes with facial loculi but no apical sucker, and a vagina that extends to near the anterior margin of the proglottid. Its species parasitise Indo-Pacific members of the genera Brevitrygon Last, Naylor et Manjaji-Matsumoto, Maculabatis Last, Naylor et Manjaji-Matsumoto and Pateobatis Last, Naylor et Manjaji-Matsumoto. New genus 2 is established as Barbeaucestus gen. n., with Barbeaucestus jockuschae sp. n. as its type species; Barbeaucestus ralickiae sp. n. is also described. Anthobothrium sexorchidum Williams, 1964 and Rhinebothrium shipleyi Southwell, 1912 are transferred to the genus as Barbeaucestus sexorchidus (Williams, 1964) comb. n. and Barbeaucestus shipleyi (Southwell, 1912) comb. n., respectively. This genus is unique among rhinebothriidean genera in that its bothridia are substantially wider than long, bear an apical sucker and at least one row of two or more facial loculi in their anterior half. Its species parasitise the genera Neotrygon Castelnau and Taeniura Müller et Henle. New genus 4 is established as Sungaicestus gen. n. with transfer of Rhinebothrium kinabatanganensis Healy, 2006, as Sungaicestus kinabatanganensis (Healy, 2006) comb. n., as its type species. Among the genera of its order, this genus most closely resembles Rhinebothrium Linton, 1890, however, despite the original description, the bothridia were found to bear, rather than lack, apical suckers., a2_This monotypic genus is known only from the freshwater stingray Urogymnus polylepis (Müller et Henle). The familial diagnosis of the Anthocephaliidae Ruhnke, Caira et Cox, 2015 is emended. The family now houses five genera., Janine N. Caira, Claire J. Healy, Fernando P.L. Marques, Kirsten Jensen., and Obsahuje bibliografii
a1_Three new species of acanthocephalans are described from marine fishes collected in Sodwana Bay, South Africa: Rhadinorhynchus gerberi n. sp. from Trachinotus botla (Shaw), Pararhadinorhynchus sodwanensis n. sp. from Pomadasys furcatus (Bloch et Schneider) and Transvena pichelinae n. sp. from Thalassoma purpureum (Forsskål). Transvena pichelinae n. sp. differs from the single existing species of the genus Transvena annulospinosa Pichelin et Cribb, 2001, by the lower number of longitudinal rows of hooks (10-12 vs 12-14, respectively) and fewer hooks in a row (5 vs 6-8), shorter blades of anterior hooks (55-63 vs 98), more posterior location of the ganglion (close to the posterior margin of the proboscis receptacle vs mid-level of the proboscis receptacle) and smaller eggs (50-58 × 13 µm vs 62-66 × 13-19 µm). Pararhadinorhynchus sodwanensis n. sp. differs from all known species of the genus by a combination of characters. It closely resembles unidentified species Pararhadinorhynchus sp. sensu Weaver and Smales (2014) in the presence of a similar number of longitudinal rows of hooks on the proboscis (16-18 vs 18) and hooks in a row (11-13 vs 13-14), but differs in the position of the lemnisci (extend to the level of the posterior end of the proboscis receptacle or slightly posterior vs extend to the mid-level of the receptacle), length of the proboscis receptacle (910-1180 µm vs 1,460 µm) and cement glands (870-880 µm vs 335-350 µm). Rhadinorhynchus gerberi n. sp. is distinguishable from all its congeners by a single field of 19-26 irregular circular rows of the tegumental spines on the anterior part of the trunk, 10 longitudinal rows of hooks on the proboscis with 29-32 hooks in each row, subterminal genital pore in both sexes, and distinct separation of the opening of the genital pore from the posterior edge of the trunk (240-480 μm) in females., a2_Sequences for the 18S rDNA, 28S rDNA and cox1 genes were generated to molecularly characterise the species and assess their phylogenetic position. This study provides the first report based on molecular evidence for the presence of species of Transvena Pichelin et Cribb, 2001 and Pararhadinorhynchus Johnston et Edmonds, 1947 in African coastal fishes., Olga I. Lisitsyna, Olena Kudlai, Thomas H. Cribb, Nico J. Smit., and Obsahuje bibliografii
Three species of Pseudodactylogyrus Gusev, 1965 (Monogenea: Pseudodactylogyridae) were collected from the gills of Anguilla reinhardtii Steindachner and A. australis Richardson from several localities in Australia and eels imported to Japan from Australia. Pseudodactylogyrus gusevi sp. n. from A. reinhardtii (type host) and A. australis in Queensland, Australia is most similar to P. bini (Kikuchi, 1929), but can be differentiated by the shorter male copulatory tube, heavy sclerotisation of the vaginal tube and the presence of a small projection of the supplementary piece of the hamulus. Pseudodactylogyrus rohdei sp. n. from A. australis (type host) in Queensland, Australia is most similar to P. anguillae (Yin et Sproston, 1948), but differs in the possession of a longer cement gland and the presence of a small projection on the supplementary piece of the hamulus. Pseudodactylogyrus bini sensu Gusev, 1965 and P. anguillae sensu Gusev, 1965 are synonymised with P. gusevi sp. n. and P. rohdei sp. n., respectively. Pseudodactylogyrus mundayi sp. n. from A. australis, originating in Tasmania, Australia and sent alive to Japan, is most similar to P. kamegaii Iwashita, Hirata et Ogawa, 2002, from which it can be discriminated by the shorter male copulatory tube and the shorter vaginal tube. Dactylogyrus bialatus Wu, Wang et Jian, 1988 from Synechogobius ommaturus (Richardson) (Gobiidae) is transferred to Pseudodactylogyrus as P. bialatus comb. n. A phylogenetic tree based on the ITS2 region of six species of Pseudodactylogyrus including P. gusevi and P. mundayi shows that P. haze from a goby diverged first, and that species from eels are monophyletic, forming three lineages differing by their zoogeographical distribution. With the three new species and one new combination proposed in this paper, Pseudodactylogyrus is now comprised of eight species infecting anguillid and gobiid fish, and a key to species is presented., Kazuo Ogawa, Makoto Iwashita, Craig J. Hayward, Akira Kurashima., and Obsahuje bibliografii