Hans Adam

Biometric and Morphogenetic Comparison of the Sibling Species Stylonychia mytilus and S. lemnae, including a Phylogenetic System for the Oxytrichids (Ciliophora, Hypotrichida)

Summary Stylonychia mytilus only differs from S. lemnae by its dorsal kineties 1–4, which are more bent apically and have a significantly greater number of cilia. These characters are difficult to recognize in vivo. Thus, we suggest that field biologists ought to employ the designation “member of the Stylonychia mytilus complex”. The cortical divisional morphogenesis is the same in the 4 clones investigated and described in detail for S. lemnae. The development of the dorsal ciliature and the division of the nuclear apparatus do not differ from those known of other Stylonychia species. The stomatogenesis begins with a proliferation of basal bodies close to the uppermost transverse cirrus. Three frontal-ventral-transverse (FVT) anlagen of the opisthe separate from the oral primordium and 3 from the right postoral ventral cirrus. In the proter anlage 1 originates from the parental undulating membranes, anlage 2 from the oral primordium of the opisthe, anlage 3 from the left posterior frontal cirrus, anlage 4 from the right posterior frontal cirrus, and anlagen 5 and 6 evolve from the right postoral ventral cirrus. The anlagen 1–6 generate 1-3-3-3-4-4 FVT-cirri. The phylogenetic sequence of the oxytrichous genera Paraurostyla (Pa), Amphisiella (Am), Gastrostyla (Ga), Histriculus (Hi), Stylonychia (St), Oxytricha (Ox), Tachysoma (Ta), Urosoma (Ur), Urosomoida (Ua), and Gonostomum (Go) is reconstructed using the method of Hennig. For this proposal, 8 morphological and morphogenetic characters were selected. Their ancestral and derived states are discussed. The monophyletic origin of the oxytrichous ciliates is assumed for their longitudinal, fan-like FVT-anlagen, which evolve during the formation of the ventral ciliature. Synapomorphies show the close relationship of oxytrichids “sensu lato” (Pa, Am, Ga) and oxytrichids “sensu stricto” (Hi, St, Ox, Ta, Ur, Ua, Go). Only Urosomoida and Gonostomum can be justified to be “true” sister groups by autapomorphies at the present state of knowledge. This method furnishes additional arguments for the validity of questionable genera, like Urosoma and Urosomoida, and for the transfer of Amphisiella to the Oxytrichidae. The loss of caudal cirri in Amphisiella and Tachysoma is interpreted as parallelism. Synapomorphies relate Histriculus Corliss , 1960 to Stylonychia Ehrenberg , 1838, but their lack of autapomorphies suggests an invalidity of Histriculus. However, the 17 FVT-cirri of “Histriculus” muscorum imply a slightly distant position, as compared with “typical” Stylonychia species, which possess 18 FVT-cirri. Stylonychia mytilus and S. lemnae are probably more evolved than S. vorax and S. pustulata, because of their more numerous synapomorphies. The scheme only proves S. mytilus and S. lemnae to be “true” sister species.

Cortical Pattern in Non‐dividers, Dividers and Reorganizers of an Austrian Population of Paraurostyla weissei (Ciliophora, Hypotrichida): A Comparative Morphological and Biometrical Study

The morphology and the regulation of cortical pattern associated with the cell size, division, and reorganization of Paraurostyla weissei (Stein, 1859) were investigated. The ranges of variation of the Austrian, Polish, and American strains were compared by biometrical analyses. The Austrian population most frequently shows 4 frontal cirri in the anteriormost and 2 in the posterior row, 4 ventral rows, 8 transverse cirri, and 7 dorsal kineties. The oral primordium originates next to the postoral ventral row. The undulating membrane field and 3 frontal‐ventral‐transverse(FVT)‐streaks for the opisthe develop as a result of the dispersion of the basal bodies of 1 or 2 cirri of the 1st ventral row. The farthest‐right ventral row is of composite origin from 2 FVT‐streaks. Three short dorsal bristle rows originating beside the right marginal row are a constant feature. In reorganizers the oral primordium characteristically possesses a group of kinetosomes extending toward the anterior right, fusing with the undulating membrane field. The development of dorsal primordia always starts in the 3rd dorsal kinety. These results provide important criteria for future species discrimination, if the examination of non‐morphological characters supplies evidence that P. weissei is a complex of sibling species.

Morphologie des Gebisses und Nahrungspraferenzen von dreizehn adriatischen Blenniiden (Teleostei, Perciformes)

The morphology and arrangement of the teeth in 13 sympatric species of the genus Blennius were investigated by SEM. All the species were collected in the upper littoral of the Northern Adriatic near Rovinj (Yugoslavia) and represent the total species inventory of the genus Blennius in this area. After analysing the content and length of the intestine, four groups with different feeding habits could be distinguished to which the morphological adaptations of the teeth could be correlated. There is a non‐selective omnivorous group of Aufwuchs‐grazer which take the inhabiting vagilfauna {Blennius gattorugine, B. incognitas, B. tentacularis), a herbivorous group (B. sanguinolentus, B. sphynx, B. canevae), a carnivorous group (B. trigloides, B. dalmatinus, B. rouxi), and a linking group between omnivorous grazers and carnivores (B. adriaticus, B. pavo, B. nigriceps). B. galerita shows a preponderance of comblike teeth and feeds exclusively scraping microscopic algae from the rocky substrate. The morphology and position of the caniniforms vary greatly within the investigated species. The dentition on the vomer is lacking in five species and seems of no consequence in the uptake of food.

Morphologie und Infraciliatur von Perispira pyriformis nov. spec., Cranotheridium foliosus (Foissner, 1983) nov. comb. und Dileptus anser (O.F. Muller, 1786) (Protozoa, Ciliophora).

Summary The morphology and the infraciliature of Perispira pyriformis nov. spec., Cranotheridium foliosus ( Foissner , 1983) nov. comb., and Dileptus anser Muller , 1786 are described from small alpine water bodies. Perispira pyriformis differs from known species of this genus by its marked pear-shaped body. The infraciliature consists of approximately 19 somatic kineties, 1 perioral kinety with paired basal bodies and a dorsal brush of 3 rows. The spiraling oral bulge may be derived from the straight oral bulge of Spathidium . This is supported by the observation that nematodesmata occur only in the anterior part of the oral bulge. Cranotheridium foliosus differs from the other species of this genus by its body shape and the nuclear apparatus. The infraciliature consists of about 25 somatic kineties and 1 perioral kinety with paired basal bodies from which very delicate nematodesmata originate. The dorsal brush is composed of several short rows at the left lateral side and 3 longer rows at the dorsal side. Perispira pyriformis and Cranotheridium foliosus have the peculiarities of the Spathidiidae and can be classified without difficulty into this family. Dileptus cygnus Claparede and Lachmann , 1859 is synonym with Vibrio anser O. F. Muller , 1786 (compare Dingfelder 1962). It is characterized by the conspicuous long and contractile proboscis and numerous contractile vacuoles extending to the top of the proboscis. The strongly varible number of the somatic kineties in different populations (see Grain and Golinska 1969) suggests the occurrence of presently inseparable sibling species.

The vascularization of the neural stalk and the pars nervosa of the hypophysis in the toad, Bufo bufo (L.) (amphibia, anura)

SummaryThe angioarchitecture of the neural stalk and the encephalo-posthypophysial portal system of the hypophysis of the toad, Bufo bufo (L.), was studied using three different methods. The neural stalk is mainly supplied by branches of the arteria infundibularis superficialis which form a widemeshed vascular network. Dorsally this network continues into the plexus of the pars nervosa. The vascularization of the pars nervosa is made up of the encephalo-posthypophysial portal system. This portal system consists of a hypothalamic branch (=portion), a mesencephalic and a mesencephalic-bulbar branch (=portion). The hypothalamic branch was found to drain the pars ventralis of the tuber cinereum as well as more dorsal regions of the diencephalon. The mesencephalic-bulbar trunk enters the hypothalamic branch. The resulting common stem of the encephalo-posthypophysial portal vein then curves around the retroinfundibular communicating artery, crosses its ventral side and runs caudally. The secondary capillary plexus of the pars nervosa is characterized by well defined capillary networks which are located at the periphery of the parenchyma of the pars nervosa, thus forming a rostral, dorsal and ventro-caudal net. The central region of the parenchyma of the pars nervosa is supplied only by main branches of the encephalo-posthypophysial portal vein. The venous drainage of the pars nervosa is via the vena hypophysea transversa.

A new cell type in the taste buds of anurans

SummaryA hitherto undescribed cell type within the fungiform papillae of the tongue of the toad, Bufo bufo (L.) and the taste-disks of the soft palate of Bombina variegata L. was identified by means of scanning and transmission electron microscopy. This cell type is characterized by an apical protrusion carrying numerous microvilli. Bundles of filaments are present in the cytoplasm of the protrusion. Vesicles with electron lucent content and microtubules are present throughout the cytoplasm of the cell.