摘要:

The taxonomy, intraspecific variation and distribution of each of the eight Israeli species of the rock‐dwelling landsnailBuliminusis described, with a new subspecieslabrosus jiftliki.The general biology of the genus is briefly described, and a key to all species and subspecies is given.Intraspecific and interspecific variation is partly associated with different environmental conditions. In the more hot regions of their distribution areas, the snails have a narrow shell, a smaller aperture, a more smooth shell surface and thick lips. The possible adaptive significance of these characteristics in hot regions is discussed.The distribution limits of many species closely coincide with both isohyets and types of substratum, suggesting that rainfall and substratum are the most important physical factors determining distribution. Vegetation in the Mediterranean region could perhaps influence such aspects of the distribution as the choice of northern or southern slopes.It is suggested that in Israel, in each climatic zone and within the limits determined by these physical factors, a faunal succession is today in operation. In the mediterranean, steppe, steppe periphery and arid regions, species which evolved or arrived recently are displacing more ancient elements. As compared with the ancient fauna, the new species have less rigid ecological requirements and are more capable of adjusting themselves to severe environmental conditions by altering their shell proportions. The last relics of the ancient fauna survive in the Judean Hills and along the isohyet 70 mm, on the brim of the extreme desert.InI. labrosusthe presence of a reverse cline, in both shell and genitalia, near the borderline withl.spirectinus, and, in addition, the presence along the borderline of a few intermediate individuals, suggests thatl. labrosusis “rolling back”l. spirectinusby keeping up a narrow belt of hybridiz

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1975.tb01889.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Observations on feeding and locomotion of the desert millipedeOrthopoms ornatuswere made in three separate habitats during the summer feeding season. The habitats were Tornillo Flat in Big Bend National Park, Texas; the Jornada Validation Site of IBP/Desert Biome near Las Cruces, New Mexico; and the base of a volcanic escarpment near Albuquerque, New Mexico.In each habitat diurnal or diel temperatures were monitored in a typical millipede microsite. Microsites included portions of aLarrea/Opuntiashrub complex (Tornillo Flat), anEphedrashrub (Jornada Site), and aSalsolashrub (Albuquerque). Adjacent mammal‐burrow temperatures were also monitored, as were soil‐surface temperatures (two habitats) and air temperatures (one habitat).Diurnal feeding and locomotion were greatest in early morning and late afternoon; nocturnal activity also occurred. Soil‐surface activity generally ceased before surface temperatures reached 35oC and began again when they cooled to about the same level. In the meantime, movement to burrows, to beneath rocks and vegetation, and to aerial portions of shrubs occurred. Additional behavioural thermoregulation was manifested by horizontal and vertical movements within shrubs, maximum air temperatures encountered being 35.5oC.Such behaviour is considered in light of recent studies of water balance and metabolism in this sp

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1975.tb01890.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

SummaryOf the lipolytic enzymes studied histochemically, lipase (Tween 80 specific enzyme) showed highest activity while non‐specific esterases (Tween 60, α‐naphthyl acetate, β‐naphthyl acetate and 5‐bromo‐indoxyl acetate esterases) and Tween 20 and Tween 40 esterases exhibited medium and lowest activities respectively. The pattern of distribution of these enzymes was found to be variable among the various elements of the hepatopancreas. Lipase. Tween 20 and Tween 40 esterases were localized at the apical parts of the R‐cell, F‐cell cytoplasm, the B‐cell vacuolar contents and the lumina of the hepatopancreatic acini. Non‐specific esterases were primarily present in the cytoplasm of the R‐cells, brush border of the tubules and connective tissue.A striking reduction in the lipase activity of the R‐ and B‐cells was apparent 4 hours after the bilateral extirpation of eyestalks. Restoration of activity was observed 48 hours after the operation. On the other hand, a rise in the level of non‐specific esterases was conspicuous 4 hours after the eyestalk amputation. This increased enzyme activity was restored to normal 24 hours after the operation.Administration of eyestalk extract into normal and de‐stalked animals caused an increase in the lipase activity of the R‐ and B‐cells. Surprisingly, the activity of non‐specific esterases also enhanced considerably in the R‐cell cytoplasm and connective tissue. The enhanced activity of lipase and non‐specific was noted 4 hours after the treatment.From the present findings it appears that the eyestalk hormone(s) are directly involved in regulating the activity of the lipolytic enzymes.The physiological role of the F‐ and B‐cells seems to be secretion and extrusion of lipase respectively. The R‐cells and connective tissue appear to be assoc

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1975.tb01891.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

The present communication deals with 11 species of rotifers from Andhra Pradesh, India belonging to six genera and three families (Notommatidae, Dicranophoridae and Asplanch‐nidae) including a new speciesAsplanchnopus bhimavaramensis, together with a key for the identification of species of the genusAsplanchnopus.All the species described are new to South India, four of them being reported for the first time from Indi

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1975.tb01892.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1975.tb01889a.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY