Biogeography of limno-terrestrial Tardigrada, with particular reference to the Antarctic fauna

The Tardigrada is a cosmopolitan phylum of pre-Pangaean origin, yet tardigrade families and genera show distinct biogeographic components isolated by two major geological events. Separate Laurasian and Gondwanan familial clusters correlate with the Triassic disintegration of Pangaea, while discrete Antarctic, Australian and New Zealand familial/generic clusters relate to the subsequent Jurassic/Cretaceous disintegration of Gondwana.     

Fuseudoxid: the elusive sexual stage of the calycophoran siphonophore Crystallophyes amygdalina (Clausophyidae: Crystallophyinae)

We have identified the sexual stage of the calycophoran siphonophore Crystallophyes amygdalina Moser, 1925 and it appears to be closely related to the undescribed Eudoxia X . In both of these sexual stages, the bract and gonophore have become fused together as a single entity. This new type of siphonophoran sexual stage warrants the creation of a particular terminology and here we name it a fuseudoxid (fused eudoxid). To demonstrate these findings, both fuseudoxids are described, and their phylogenetic relationships as well as the systematic position of the genus Crystallophyes are discussed. The subfamily Crystallophyinae Moser (1925) is re-established.     

Serological Relationship of the Tacaribe Complex of Viruses to Lymphocytic Choriomeningitis Virus

By means of the indirect fluorescent-antibody test, cross serological reactivity was demonstrated between lymphocytic choriomeningitis (LCM) virus and the viruses of the Tacaribe complex. Antisera to all members of the Tacaribe complex reacted with LCM virus; LCM antisera gave significant staining of Amapari virus, but minimal or inconsistent reactions with Tacaribe virus, and no reaction with two other viruses of the Tacaribe complex. A low level cross-reaction was observed in complement fixation tests of Machupo and Pichinde antisera against LCM antigen. Immunization with Tacaribe and Amapari viruses did not protect mice against challenge with LCM virus. Because of the identical appearance of the virions, the sharing of antigens, and the many biological similarities between LCM and the Tacaribe complex viruses, it is proposed that they be considered as constituting a new taxonomic group of viruses.     

Morphological and Cytochemical Studies on Lymphocytic Choriomeningitis Virus

Lymphocytic choriomeningitis (LCM) virus was observed by electron microscopy in thin sections of infected tissue cultures. The particles were pleomorphic and varied greatly in size. The smaller particles (50 to 200 nm) appeared to be spherical, whereas the largest (over 200 nm) were often cup-shaped. All particles contained one to eight or more electron-dense granules which were removed by ribonuclease. The particles were formed by budding from the plasma membrane and appeared to have spikes. The morphological evidence suggests that LCM should be considered as belonging to the presently unclassified group of lipoprotein-enveloped ribonucleic acid viruses.