Dictyterina cholodkowskii (Skrjabin, 1914) is recorded from iMnius collurio L. in Bulgaria (new geographical record). The species is redescribed and figured. A full list of synonyms is presented; it includes, among the other synonyms, Deltokeras delachauxi Hsii, 1935 (new synonym), Biulerina passerina of Oshmarin (1963) and Paruterina parallelipipeda of Paspalev and Paspaleva (1972). A survey of published records characterizes D. cholodkowskii as limited to the Palaearctic in six species of the genus Lanius (Aves, Passeriformes, Laniidae).
Two species with different resistances to alkaline pH, the glycophylic Triticum aestivum (wheat) and the halophilic Chloris virgata, were chosen as test organisms. The salt-alkaline (SA) mixed stress conditions with different buffer capacities (BC) but with the same salt molarities and pH were established by mixing neutral (NaCl, Na2SO4), and alkaline salts (NaHCO3 and Na2CO3) in various proportions. Growth, photosynthetic characteristics, and solute accumulation of the seedlings were monitored to test the validity of BC as a decisive index of alkali-stress (AS) intensity in SA mixed stress. At the same salinities and pHs, the relative growth rate, the content of photosynthetic pigments, and net photosynthetic rates of wheat and C. virgata decreased, while Na+ content and Na+/K+ ratios in shoots increased with increasing BC. Hence BC was a true measure of AS intensity at mixed SA stress and the alkali-resistance mechanism of plants was easy to interpret. BC of soil solution is an important parameter for estimating the alkalization degree of salt-alkalized soil. and C.-W. Yang ... [et al.].
Hysterothylacium winteri sp. n. (Nematoda: Anisakidae) was collected from the intestine of a marine-estuarine fish, Eleginops maclovinus (Valenciennes) (Perciformes: Eleginopsidae), from Abtao in the Gulf of Ancud, Chile. Sixteen (51.6%) out of 31 fish were infected; the intensity was 1-10 (mean 4) worms/host. The new species belongs to the group of congeners possessing one double pair of postanal papillae. By possessing a lateral pair of phasmids situated near the tip of tail, H. winteri most closely resembles Hysterothylacium habena. The new species can be distinguished by the lip flanges forming broadly rounded points and the equal, short spicules (320-400 µm long) representing 0.9-1.7% of body length.
Larval development of the nematode Onchocamallanus bagarii (Karve et Naik, 1951), recovered from the intestine of the fish Bagarius bagarius (Hamilton) was studied under laboratory conditions. The cyclopoid copepods Mesocyclops leuckarti (Claus) and M. crassus (Fischer) were infected with first-stage larvae from female uteri and maintained at temperatures 29-30°C. After being swallowed by the copepods, first-stage larvae burrow through the intestinal wall and reach the haemocoel of the copepods and there they grow and moult twice to attain the third and infective-stage. First-stage larvae become ensheathed after 65 hours of infection and second-stage larvae first appeared on day 3 post infection (p.i.). The second moult occurred on day 5 p.i. The larval stages occurring during development are described.
A new nematode species, Philometroides caudata sp.n., is described from the swimbladder (under the serosa cover) of the freshwater pimelodid catfish, Rhamdia guatemalensis, from cenotes (— sinkholes) in Yucatan, southeastern Mexico. It differs from all hitherto known members of the genus, except P. maplestoni (Travassos, Artigas et Pereira, 1928), in having the functional anus, the conical tail with a terminal knob-like structure and the oesophagus without an anterior inflation in female, and in the structure of the caudal end in male. It can be distinguished from P. maplestoni (described only from females) by the extent of embossed cuticle, the size of body and the host type. P. caudata, representing a Neotropical element, is the first Philometroides species reported from freshwater fishes in Mexico.
Rates of the net photosynthetic CO2 uptake the import of '“♦C-labelled assimilates in developing groundnut leaves on the 5"’, 9‘*' and I6"i positions from the stem base were followed over a 20 d maturation period. Maximum import of labelled assimilates into the leaf was observed on the 2"^ day after leaf emergence, when the developing leaf had attained 10-12 % of its fmal leaf area (% Aj). Thereafter, by the day the •‘^C-import rate declined rapidly and asymptotically to a near zero value. The rapid decline in import was offset by a rapid rise in /’n. Pjsj was first observed at 20-30 % Af. Maximum values were attained by the 6‘*’ day, irrespective of leaf area attained by the developing leaves, and were maintained up to the end of the experiment.