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2000. Volume 7. No. 3. Contents PULMONARY MECHANORECEPTORS AND THE MODULATION OF VENTILATORY PATTERN AND VARIABILITY IN THE MARINE TOAD, Bufo marinus Previous studies reveal that chemoreceptors and pulmonary stretch receptors (PSR) have distinct effects on respiratory patterns and mechanics in toads. Removal of pulmonary feedback by vagotomy modifies behavior of glottal and narial valves, but has no effect on respiratory patterns. Since vagotomy may have a transformational effect on ventilation, I looked at the relationships between pulmonary feedback and ventilatory mechanics, pattern, and variability by unidirectionally ventilating (UDV) toads' lungs to set lung pressure and volume. UDV dampens oscillations in both slowly and rapidly adapting PSRs. Changes in lung pressure did not affect narial and glottal timing during inflation breaths in UDV toads. This result indicates that the coordination of narial and glottal valves do not depend directly on PSR output and that studies reporting alteration of valve timing in vagotomized toads may be looking at a transformational effect caused by denervation. Buccal pump stroke, also became significantly slower while ventilatory entropy became smaller as static lung volume was increased. I conclude that levels of PSR output are relevant to the control of buccal pumping frequency but not valve timings and that qualitative aspects of PSR activity (presence of oscillations) are important for generation of adaptive variation in the system's output. Key words: Anuran, Toad, Bufo marinus, Mechanoreceptors, Ventilatory control, Respiratory physiology, Entropy, Lung. NUCLEAR DNA CONTENT IN SOME GREEN TOADS (Bufo viridis COMPLEX) OF TURKEY AND IRAN 15 specimens from western Turkey, northern and southern Iran were examined. According to external characters and geographic position, the toads seem to belong to B. v. viridis, to the so-called Transcaspian population group, and to B. v. kermanensis, respectively. The diploid level of toads was evidenced from DNA flow cytometry. The distribution of diploid and polyploid toads in Western Asia is discussed. Key words: Bufo viridis complex, Turkey, Iran, Genome size, DNA flow cytometry. DISTRIBUTION AND BIOGEOGRAPHY OF NON-MARINE CRETACEOUS TURTLES During the Cretaceous, non-marine turtles show strong patterns of provincialism, mirroring the pattern of land masses resulting from the breakup of Pangea since the Jurassic. These patterns are a result of several factors, of which vicariancy and ecological controls on the distribution of groups of turtles are considered the most significant. The large scale patterns, such as the dominance of pleurodires in the southern land masses, including Africa, South America, and India, and the dominance of Cryptodires in the northern land masses cannot be strictly attributed to vicariancy because exceptions to both distributional patterns are present. The pleurodires in Europe and North America during the Late Cretaceous may reflect the removal of the barriers that prevented the terrestrial faunal interchange between the northern and southern continents. Two groups of cryptodires that occurred in the southern continents during the Cretaceous, the Meiolaniidae and Otwayemys, seem to reflect a widespread distribution of the very primitive cryptodires which were diverse prior to the breakup of Pangea in the Early or possibly Middle Jurassic. In Laurasia, three regions of turtle diversity can be identified, the North American region, the European region, and the Asian region. In the Early Cretaceous, North American region is dominated by members of the Paracryptodira, and the Asian region is dominated by members of the Eucryptodira. Europe includes taxa from both groups. In the Late Cretaceous, Eucryptodires become increasingly more abundant and diverse in North America. The Baenidae which are not found outside North America appears to be truly endemic to this region. Two groups of "modern," non-marine cryptodires or Chelomacryptodira, the Testudinoidea and the Trionychoidea, appear to have an Asian origin. Both have their earliest record in the Neocomian of Japan. Key words: Non-marine turtles, Cretaceous, Phylogeny, Distribution, Gondwana, Laurasia. Triceratolepidophis sieversorum, A NEW GENUS AND SPECIES OF PITVIPER (REPTILIA: SERPENTES: VIPERIDAE: CROTALINAE) FROM VIETNAM A new genus and species of pitviper from the Annam Mountain Range, Quang Binh Province, Vietnam are described. The description is based on a single male specimen. This member of the Trimeresurus group is characterized by the presence of raised horn-like multiple supraoculars and by having the unique structure of the dorsal scales showing a keel consisting of three horn-like upraisings as well as the unique microdermatoglyphic pattern of the Oberhäutchen, which is tessellate fimbriate. First notes on its biology are provided and possible relationships of this new and striking taxon are discussed. Key Words: Reptilia, Squamata, Serpentes, Viperidae, Crotalinae, Triceratolepidophis genus nov., Triceratolepidophis sieversorum species nov., Phong Nha Nature Reserve, Vietnam. THE MATING CALL AND MALE RELEASE CALL OF Bufo raddei STRAUCH, 1876 WITH SOME PHYLOGENETIC IMPLICATIONS The mating call of Bufo raddei is analyzed and described for the first time. Although species-specific, important parameters (call duration, amplitude-time waveform of single pulses, absence of interpulse intervals at higher body temperatures) of the mating call show a similar structure to those of the allopatric Bufo calamita, mainly differing by lower pulse rates. B. raddei mating calls differ from those of diploid, triploid and tetraploid representatives of the parapatric Eurasian Bufo viridis complex which have a pulsed structure with distinct interpulse intervals. The release call of male B. raddei consists of a single pulse group with slight frequency modulation and appears similar to the release call of B. calamita, but differs from those in the B. viridis complex which always are subdivided in pulse groups. We suggest the occurrence of two different types of amplitude modulation as an indication for a possible divergence of two evolutionary lineages, the B. calamita/B. raddei lineage and the B. viridis complex lineage. Furthermore, we compare these results with other published phylogenetic data on these taxa. Key words: Bufo raddei, Bufo calamita, Bufo viridis complex, Mating calls, Male release calls, Amplitude modulation, Phylogeny. SOME SPECULATIONS ON THE LIFE STYLE OF PERMO-CARBONIFEROUS SEYMOURIAMORPH TETRAPODS (DISCOSAURISCIDAE): IMMATURITY OR PAEDOMORPHOSIS? The recent knowledge on the development and paleoenvironment of Permo-Carboniferous seymouriamorph tetrapods of the family Discosauriscidae are summarized and compared with those of existing Amphibia. The analysis of many factors (skeleton structure, ontogenesis and climatic conditions) allows to evaluate a probability of paedomorphic development of Discosauriscidae as at least very possible. Key words: Permo-Carboniferous, Discosauriscidae, Paedomorphosis, Immaturity. SHORT COMMUNICATIONS THE RADIATION OF Pleurodeles TO NORTH AFRICA COULD BE RELATED TO ADDITIONAL THYROID TISSUE Key words: Pleurodeles waltl, Thyroid glands, Metamorphosis, Amphibian plasticity. PRELIMINARY OBSERVATIONS AND COMMENTS ON SYNTOPIC OCCURRENCE OF LIZARDS IN IRAN Relatively little is known about the ecology of lizards in Iran. This paper serves as a brief introduction to five representative biotopes and their associated lizard species living syntopically, based largely on my own observations. The selected localities are found in 1) Masjed Soleyman, foothills of the Zagros Mountains, Khuzestan; 2) Kupal dunes, on the Mesopotamian Plain, Khuzestan; 3) Shah 'Abbas Caravanserai, Dasht-e Kavir, on the Central Plateau; 4) an abandoned village in Sistan, ruined buildings and loose loess substrate; 5) Hyrcanian Forest, northern slopes of lower Alborz Mountains and the Gorgan region. The biotopes are characterized briefly and the concept of syntopy is discussed. Key words: Iran, Sauria, Natural history ecology, Sympatric species. EPICORACOID OVERLAP INDICES IN NEWTS OF THE GENUS Triturus (Amphibia: Salamandridae) According to the epicoracoid overlap index, Triturus vulgaris, T. cristatus, T. dobrogicus, and T. karelinii form a rather homogenous group. Until now, members of the genus Triturus are the only arciferal amphibians in which the overlap index is less than 1. Key words: Triturus, epicoracoid position. BOOK REVIEW |
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