Ultrastructure of the male reproductive organs in the interstitial annelid Sphaerosyllis hermaphrodita (”Polychaeta”, Syllidae)

 The reproductive organs of the simultaneous hermaphrodite Sphaerosyllis hermaphrodita (Syllidae, Exogoninae) were examined by TEM and reconstructed from ultrathin serial sections. Oocytes are produced in the 11–13th chaetigerous segments and then attached to the outer body surface. The male organs comprise a seminal vesicle, testes, sperm ducts and copulatory chaetae. The unpaired seminal vesicle is an uncompartmented cavity above the gut and within the chaetigerous segments 8–10. Its interior is lined with a layer of gland cells that degenerate as spermatogenesis in the vesicle proceeds. The testes are situated ventrolaterally, close to the seminal vesicle in the 9th chaetigerous segment. They contain cells at early stages of spermatogenesis, which are connected to one another by zonulae collares. The testes and seminal vesicle are enclosed in epithelia. Paired sperm ducts run ventrally from about the midline of the body under the seminal vesicle and into the parapodia of the 9th chaetigerous segment. There they open, together with the protonephridia of this segment, to the outside next to the stout copulatory chaeta. Each sperm duct consists of six cells, the luminal surface of which bears microvilli but no cilia. Only in animals with fully differentiated sperm does the small opening of the proximal duct cell in each duct give access to the seminal vesicle. The mode of sperm transfer is discussed. Accepted: 9 December 1996     

Are there two cryptic species of the lesser jerboa Jaculus jaculus (Rodentia: Dipodidae) in Tunisia? Evidence from molecular,morphometric, and cytogenetic data

Jerboas belonging to the genus Jaculus are widely distributed rodents inhabiting Palearctic desert and semi‐desert areas. Previous studies on the lesser Egyptian jerboa Jaculus jaculus showed the existence of various morphological forms of controversial taxonomic status. They were sometimes related to two different species, J. jaculus and Jaculus deserti, although this has not been recognized in recent taxonomic updates. To clarify the systematic status of J. jaculus in Tunisia, we performed molecular (phylogenetic analyses of cytochrome b sequences), morphological (multivariate analyses of 13 skull measurements) and karyotypic (standard preparations from bone marrow cells) analyses on a number of specimens collected from ten localities. Our analyses revealed two monophyletic, well differentiated clades, with a mean genetic divergence value (K2P = 10.9 ± 0.01%), which is within the range of distances generally observed between rodent species. Morphometric analyses clearly separated populations of the two genetic clades from each other. However, karyotypes of individuals from both clades appeared similar. Individuals from both molecular clades/morphometric groups were found in sympatry in most of the localities sampled. These results, as obtained from a restricted area of the total distribution, suggest that there are two separate species within the currently accepted J. jaculus in Tunisia. Alternative hypotheses such as the occurrence of a strong, ancient phylogeographic structure, or the presence of pseudogenes, are also considered to account for the results obtained. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 673–686.     

Ultrastructure of sympathetic ganglion cells and granule-containing cells in the paracervical (Frankenhäuser) ganglion of the newborn rat

Summary A study was made of the ultrastructure of the paracervical (Frankenhäuser) ganglion of the newborn rat, using immersion fixation by glutaraldehyde (2.5%) followed by OsO₄ (1%), or KMnO₄ (3%) fixation. The cells containing dense—core vesicles were divided into three groups: (1) primitive sympathetic cells, (2) cells containing some dense-core vesicles 700–1100 Å in size and structurally resembling sympathetic neurons, called principal neurons, and (3) cells containing many dense-core vesicles with a larger, darker dense core, 800–2000 Å in diameter, called granule-containing cells. Using glutaraldehyde-osmium fixation, the principal neurons were further divided into dark and light cells on the basis of electron opacity of the cytoplasmic matrix. The granule-containing cells were believed to correspond to the small, intensely fluorescent cells (SIF-cells) previously described using the formaldehyde-induced fluorescence technique. On the basis of the amount of granules, the granulecontaining cells were classified as mature or maturing SIF-cells and as more primitive SIF-cells, and developing sympathicoblasts. The development of synapses in autonomic ganglia was discussed.Grant: The Finnish Medical Foundation.     

Is Sperm Ultrastructure Useful in Polychaete Systematics? An Example Using 20 Species of the Fabriciinae (Polychaeta: Sabellidae)

The utility of sperm morphology in the systematics of polychaetes has been questioned in the past. This doubt stems from a problem with methodology, not with sperm morphology. It is argued that sperm characters used in combination with other morphological features have utility at various hierarchical levels. As a test of this proposition males in species from each of the following 10 fabriciin genera: Augeneriella, Fabricia, Fabriciola, Fahricinuda, Manayunkia, Novafabricia, Parafabricia, Pseudofabricia, Pseudofabriciola and an undescribed new Genus A (Fitzhugh et al., in preparation), were examined in order to provide new characters for phylogenetic systematic studies. All species were found to have a dorsal sperm duct running beneath the faecal groove of the thoracic region. No sabellin sabellids or serpulids have this duct. The above Fabriciinae have spermatids developing in large clusters of several hundred cells. Serpulids and sabellins nearly always have sperm developing in tetrads or small groups. Fabriciins studied also have a sperm structure distinct from the Sabellinae and the Serpulidae. Proposed synapomorphies for the members of the Fabriciinae, based on sperm structure, include (1) a thick glycocalyx over the plasma membrane; (2) a distinctive nuclear projection, with an anterior thickening of the nuclear membrane; (3) a thickened. spiraling ridge of nuclear membrane; (4) an extra-axonemal sheath and (5) a unique sheath of mitochondrial material in the midpiece. Within the sub-family there were differences among species in sperm structure. This variability involves acrosome morphology; the structure of the sperm nucleus and nuclear projection; the spiral of thickened nuclear membrane; the structure of the extra-axonemal sheath; the mitochondrial sheath. The monophyly of the Fabriciinae (sensu Fitzhugh, 1991, 1993) is well supported by this analysis. The status of Caobangia is still unresolved and a close examination of this genus is warranted.     

Ultrastructure of the germ cells in the testis of matrinxã, Brycon cephalus (Teleostei, Characidae)

This study describes at ultrastructural level the germ cells in the testis of matrinx? (Brycon cephalus) raised in captivity. The specimens 'matrinx?' were maintained in four breeding tanks of 200 m(2), at the Aquaculture Research Center at Vale do Ribeira-CEPAR, from Fishery Institute, in Pariquera-A?u City, S?o Paulo, Brazil. The samples were collected from March 1994 to February 1996. The testis has been classified as tubular unrestricted spermatogonial type, in which four stages of germ cells can be distinguished as follows: spermatogonia, spermatocytes (primary and secondary); spermatids and spermatozoa.     

Ultrastructure of the spore in four Japanese species of Ptychomitrium Fürnr. (Musci)

The ultrastructure of the mature spore in four Japanese species of the acrocarpous moss genus Ptychomitrium is presented. In all species the spores have a similar pattern: there is no recognisable aperture nor sporoderm polarity, exine and perine are poorly developed, cytoplasm only occasionally shows polarity, and plastids have a well developed inner membrane system. The presence of frequent intine protrusions is a remarkable feature of this genus. A multilaminar structure of the exine, already observed in Grimmia, occurs also in these species although here it is less pronounced. The significance of these features is discussed within these species, as well as in comparison to other taxa, especially the genus Grimmia.     

Revision of the Agrilus beatissimus species–group (Coleoptera,Buprestidae) with description of five new species from Southeast Asia

The newly defined Agrilus beatissimus species–group comprising seven species from Southeast Asia is revised. The key to species is provided and complemented with illustrations of habitus, genitalia and type specimens. The following five new species are described: Agrilus bilyanus sp. nov. (Thailand); A. campana sp. nov. (Laos); A. galazopos sp. nov. (Laos); A. plurifrons sp. nov. (Laos, Myanmar) and A. undatus sp. nov. (Laos). Comprehensive commented references, data on type specimens and new faunal records are cited. The distribution is updated for A. beatissimusDescarpentries and Villiers 1963 and A. dunoyeriBaudon 1968.     

A checklist of the genus Tomosvaryella Aczél (Diptera: Pipunculidae) from the Middle East with the description of a new species

A checklist of 39 species of the genus Tomosvaryella Aczél (Diptera, Pipunculidae) known from the Middle East is provided. A new species, T. hamata Majnon Jahromi &; Kehlmaier sp. n. is described from southern Iran and diagnostic characters of male and female terminalia are illustrated. Tomosvaryella dentiterebra (Collin, 1949 Collin, J. E. (1949): Results of the Armstrong College Expedition to Siwa Oasis (Libyan Desert), 1935, under the leadership of Prof. J. Orner-Cooper. Diptera Empididae, Dolichopodidae, Aschiza and Acalypterae. Bulletin de la Societe Fouad I^erd'Entomologie, 33, 75–225. [Google Scholar]) is redescribed and male and female terminalia are illustrated for the first time. A phylogenetic maximum-likelihood analysis and uncorrected pairwise genetic distances of 18 out of 22 Iranian species of Tomosvaryella based on DNA barcodes of the mitochondrial COI gene are presented and also discussed.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:FF8C116D-0C92-431A-B52C-11F3711B6A62     

A new species of Simaba (Simaroubaceae) from Pará, Brazil,with a key to the species north of the Amazon River

A new species,Simaba cavalcantei, is described and illustrated. It is considered to be intermediate between sectionsGrandiflorae andFloribundae and is distinguished from potentially sympatric species in a key to the species occurring north of the Amazon River.     

Two new species of deepwater cardinalfish from the Indo-Pacific, with a definition of the Epigonus pandionis group (Perciformes: Epigonidae)

Two new Indo-Pacific species of deepwater cardinalfish, Epigonus lifouensis and E. tuberculatus are described based on the specimens collected from the Loyalty Islands and Cocos-Keeling Islands, respectively. These species belong to the Epigonus pandionis group defined as lacking an opercular spine, having more than 43 pored lateral-line scales to the end of the hypural and dorsal-fin rays VII-I, 9–11. Epigonus lifouensis is distinguished from other members of the group by a combination of the following characters: ribs present on the last abdominal vertebra; tongue toothless; tubercle absent on inner symphysis of lower jaw; eye elliptical; total gill rakers 24–25; pectoral-fin rays 18–19; pyloric caeca 10–13; body depth 17.0–17.1 % SL; and posterior half of oral cavity and tongue black. Epigonus tuberculatus is distinguished from other members of the group by a combination of the following characters: ribs on the last abdominal vertebra reduced or absent; tongue toothless; tubercle present on inner symphysis of lower jaw; total gill rakers 21–22; pectoral-fin rays 19–20; pyloric caeca 8–10; orbital diameter 14.5–15.4 % SL; and lower-jaw length 16.0–17.6 % SL. A key to the species and some comments on the group are provided based on examination of all members (nine species, including two new species) of the group.     

Ultrastructure of the dendritic outer segments of sensory cells in poreless (‘no-pore’) sensilla of insects

Summary Poreless sensilla with inflexible sockets in insects presumably house hygro- and thermoreceptors (type-1, type-2 receptors). The dendritic outer segments of these receptor cells were studied mainly in cryofixed antennae of two species of moth (Antheraea pernyi, A. polyphemus) and one beetle (Aleochara curtula). As a rule two type-1 receptor cells are present. Their dendritic outer segments do not branch. They project into the distal cuticular parts of the sensillum and are in close contact with its four-layered wall. The segments differ in shape and microtubule density. As well, in A. curtula, the microtubules are interconnected by electron-dense material for some distance, thus forming a tubular body-like structure of 1.3 m length. The dendritic outer segment of the single type-2 receptor cell is branched and lamellated. Its lamellae are connected by structures similar to septate junctions, which occupy about 70% of the total surface of the lamellated portion of the dendrite. In tangential sections, the septa appear as parallel strands approximately perpendicular to the long axis of the dendritic segment. The structure of type-1 receptors is discussed with regard to the hypothesis for a mechano-electrical transduction. The possible functions of lamellation and junctional connections in type-2 receptors are discussed.Supported by the Deutsche Forschungsgemeinschaft (SFB 4/G1)     

New data on the Cricetidae from the Miocene “Terre Rosse” of Gargano (Apulia,Italy)

The Gargano “Terre Rosse” deposits are paleokarst fissure fillings found in the Mesozoic limestone of the Apricena-Poggio Imperiale area. They are an important source of information for evolutionary and paleobiogeographic studies. The Late Miocene-Early Pliocene assemblages found in the Terre Rosse attest the complex history of endemic faunal distribution in a paleoarchipelago. Based on the cricetid samples from six distinct fissures (F15, F21a, F21b, F21c, F1, F9, NBS) stored in the Department of Earth Sciences of the University of Florence, three species of endemic cricetids are described: the small-sized Hattomys beetsi, the middle-sized Hattomys nazarii, and the large-sized Hattomys gargantua. The specimens from fissure F15 are attributed to H. beetsi, those from F21a-b to the transitional form Hattomys beetsi-nazarii, those belonging to NBS are ascribed to H. nazarii, whereas those from F1 and F9 are classified as H. gargantua. F21c is considered contaminated with material from different fissures. In line with previously published results, the analysis confirms that the endemic cricetids underwent a remarkable increase in size through time. The morphological variations show a marked trend towards increasing enamel thickness, but also the tendency of the cusps to assume a carved-in aspect. The variations of the morphological characters confirm that the three species likely belong to the same lineage.     

Description of the oöcysts of theree new species ofEimeria (Apicomplexa: Eimeriidae) from geckoes (Auria: Gekkonidae)

Three new species ofEimeria are described from the faeces of geckoes. Oöcysts ofEimeria vittati n. sp. fromGekko vittatus are elongate-ellipsoid 34.3 × 16.9 (32.5–36.5 × 16.5–17.5) μm; shape index (mean length/mean width) 2.03. Its sporocysts are ovoid 11.0 × 6.5 (10–12.5 × 5–7.5) μ; shape index 1.7. Oöcysts ofE. simonkingi n. sp. were found inG. vitttus and two subspecies ofPhelsuma lineata, and are spherical to subspherical 20.5 × 19.4 (19.5–22 × 17.5–21) μm; shape index 1.06. Its sporocysts are ellipsoidal 9.9 × 5.9 (8–11.5 × 5.5–7) shape index 1.7. Oöcysts ofE. tokayae n. sp. fromG. gecko were spherical or subspherical, 18.3 × 18.2 (17–21 × 13–20.5) μm; shape index 1.01. Its sporocysts are ellipsoidal 9.2 × 5.9 (8–11.5 × 5.5–7) All of the new species ofEimeria from gekkonid lizards described since 1986 are listed in a reference table, and details of their oöcyst and sporocyst measurements and their morphology are given.     

Ultrastructure of the spermatozoa of<Emphasis Type="Italic"> Parenterodrilus taenioides</Emphasis> (Protodrilida: “Polychaeta”) and its phylogenetic significance

The interstitial annelid Parenterodrilus taenioides from coral sands of the island of Moorea (French Polynesia) is a mouthless species characterized by a vestigial non-functioning alimentary canal and a distinctive body shape. It is the only known annelid that has a non-functioning gut and no symbiotic bacteria. Parenterodrilus is thought to represent the sister group of the well-known taxon Protodrilus, generally recognized as Protodrilidae. An ultrastructural study revealed that, as in Protodrilus spp., the males of P. taenioides have lateral organs, i.e. paired epidermal, glandular and ciliated grooves, in the anterior body region where the sperm ducts are located. As in Protodrilus two types of spermatozoa were found, commonly called euspermatozoa and paraspermatozoa. Both types are filiform and the euspermatozoa, like those in Protodrilus spp., have a characteristic midpiece reinforced by symmetrically arranged supporting structures and reduced mitochondria. The ultrastructure of the spermatozoa in P. taenioides and Protodrilus spp. is basically the same but the species can be distinguished from each other on the basis of particular structural details of spermatozoa and the pattern of lateral organs. The two types of spermatozoa and the epidermal lateral organs are unique features of these two taxa; as they are not present in any other potentially related taxon, such as Saccocirrus and Protodriloides, they very likely represent autapomorphies of Protodrilidae. In Protodrilus spp. spermatophores are deposited on the epidermis of the females, whereupon sperm are released and penetrate the body wall. Since in polychaetes the structure of the sperm is correlated with the fertilization biology, the similar structure of sperm suggests that sperm transfer and fertilization are very probably the same in P. taenioides as in Protodrilus.This paper was presented at the symposium Morphology, molecules, evolution and phylogeny in Polychaeta and related taxa held in Haus Ohrbeck, Osnabrück, in September 2002, and is dedicated to Prof. Dr. Wilfried Westheide on the occasion of his 65th birthday     

Morphological and karyotypic analysis of five blackfly species of the genus Cnetha (Diptera: Simulidae): description of the novel species from the Dzhrvezhskiĭ canyon in Armenia

Morphological and karyotypical features of a new blackfly species Cnetha akopi sp. n. from Armenia are described. Comparative analysis of the new species and four closely related endemic species from Caucasus is performed. Photographic maps of polythene chromosomes are provided.     

A new species of the morid genusgadella (teleostei: gadiformes) from the galápagos islands

A new species of deepwater morid fish,Gadella thysthlon, is described on the basis of five specimens from the Galápagos Islands. It differs from other species ofGadella by its low dorsal and anal fin ray counts (8+56–58 and 64–66 respectively), moderate number of gill rakers (4–5+9–11), small luminous organ that is closer to the anus than the interventral line, and its dark body, bright red-orange median fins with dark bases, and melanophores on the tongue apex and the palatal midline.     

Taxonomic review of the genus Coelopisthia F?rster (Hymenoptera:Pteromalidae) from China,with four new species

The pteromalid genus Coelopisthia from China is studied with eight species including four new species and two newly recorded species: C. dasycladus sp. nov., C. gracilentus sp. nov., C. pseudaletia sp. nov., C. condensus sp. nov., C. areolata Askew and C. caledonica Askew. A key to Chinese species is provided. All the specimens are deposited in the Zoological Museum, Institute of Zoology, Chinese Academy of Sciences.