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1642. A new genus with two new species of lecanicephalidean tapeworms (Cestoda) from the mangrove whipray, Urogymnus granulatus (Myliobatiformes: Dasyatidae),from the Solomon Islands and northern Australia
- Creator:
- Herzog, Kaylee S and Jensen, Kirsten
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- skenovací elektronová mikroskopie, scanning electron microscopy, Tichý oceán (západní oblast), West Pacific Ocean, Lecanicephalidea, apical organ, Polypocephalidae, Indo-West Pacific region, 2, and 59
- Language:
- English
- Description:
- A new lecanicephalidean genus is erected for cestodes previously recognised as "New Genus 12" (Polypocephalidae) in a phylogenetic analysis of the interrelationship of members of this order. Examination of the cestode fauna of the mangrove whipray, Urogymnus granulatus (Macleay) (Myliobatiformes: Dasyatidae) from the Solomon Islands and northern Australia revealed the existence of specimens representing two new species, consistent in morphology with "New Genus 12." Corollapex gen. n. is unique among the 24 valid lecanicephalidean genera in its possession of an apical organ in the form of an external retractable central disk surrounded by eight concave muscular, membrane-bound pads and an internal heterogeneous glandular component. The two new species described herein, Corollapex cairae sp. n. (type species) and Corollapex tingoi sp. n., differ from one another in overall size and number of mature and immature proglottids, and are noted to demonstrate a differential distribution between mature and juvenile host individuals. Additional species diversity in the new genus, beyond C. cairae sp. n., C. tingoi sp. n., and "New Genus 12 n. sp. 1" of Jensen et al. (2016) is suggested. Corollapex gen. n. appears to be restricted to dasyatid hosts in the Indo-West Pacific region., Kaylee S. Herzog, Kirsten Jensen., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1643. A new hyperapolytic species, Trilocularia eberti sp. n. (Cestoda: Tetraphyllidea), from Squalus cf. mitsukurii (Squaliformes: Squalidae) off South Africa with comments on its development and fecundity
- Creator:
- Pickering, Maria and Caira, Janine N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- tapeworms, taxonomy, growth, life history, sharks, and parasites
- Language:
- English
- Description:
- A new species of tetraphyllidean cestode in the genus Trilocularia is described from an undescribed shark species, Squalus cf. mitsukurii, off the coast of South Africa. Trilocularia eberti sp. n. is the second known member of its genus, and like its congener, T. gracilis (Olsson, 1866-1867) Olsson, 1869, is extremely hyperapolytic, dropping proglottids from its strobila while they are still very immature. Characteristic of the genus, it possesses a distinctive scolex with triloculated bothridia, but differs conspicuously from its congener in its possession of an anterior loculus that is much larger in width relative to the paired posterior loculi, and also in its possession of an anterior, enlarged region of its free proglottids that is triangular with a slit-like ventral aperture, rather than rounded and cup-like. This anterior region of the free proglottid is used in attachment, and its development is described. For assessment of fecundity, an attempt was made to record all free proglottids of all ages found in both host individuals, and yielded an average estimate of 362 free proglottids being produced per individual worm of T. eberti sp. n. Both Trilocularia species parasitize sharks of the genus Squalus, and given the host specificity typically exhibited by tetraphyllideans and preliminary examinations of other members of this shark genus, it is likely that other Squalus species will be found to host additional new Trilocularia species.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1644. A new Juncus of the section Tenageia from Morocco and Egypt
- Creator:
- Kirschner , Jan, Rejdali , Mohamed, and Drábková , Lenka
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- annual species, Juncaceae, Morocco, and taxonomy
- Language:
- English
- Description:
- A new annual species, Juncus maroccanus, of the section Tenageia, closely allied to Juncus foliosus Desf., is described from N Morocco. It differs from the latter in having smooth, glossy seeds, capsule shorter than perianth and shortly mucronate. The new species is known from a macrolocality in the Ksar-el-Kebir region, where it grows in non-saline sandy seepage sites. Another, much older specimen was collected in 1835 by W. Schimper in the Sinai Peninsula, Egypt. Syntype specimens of Juncus rhiphaenus Pau et Font Quer were examined and found to be conspecific with Juncus foliosus.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1645. A new libelluloid dragonfly from late Paleocene deposits in Argentina (Odonata: Italoansida)
- Creator:
- Petrulevičius , Julián F. and Nel, André
- Type:
- article, model:article, and TEXT
- Subject:
- Odonata, libelluloid dragonfly, new genus and species, late Paleocene, Argentina, and South America
- Language:
- English
- Description:
- A new genus and species of "libelluloid" dragonfly, Jujusia maizgorda gen. n., sp. n., of the clade Italoansida Bechly, 1996, from the late Paleocene, Maíz Gordo Formation, north-western Argentina, is described. Its phylogenetic relationships within the clade Cavilabiata Bechly, 1996 are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1646. A new live trap to catch blind mole rats (Spalax sp.)
- Creator:
- Arslan, Atilla
- Type:
- article, model:article, and TEXT
- Subject:
- live trapping and subterranean mammal
- Language:
- English
- Description:
- A design of a newly developed metal pipe-type trap for catching live mole rats is presented. In all field trials the trap was efficient and thus meaningful alternative to other types of live traps. This trap may prove to be useful also to catching the other subterranean mammal species.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1647. A new look at discontinuous respiration in pupae of Hyalophora cecropia (Lepidoptera: Saturniidae): Haemocoelic pressure, extracardiac pulsations and O2 consumption
- Creator:
- Sláma, Karel
- Type:
- article, model:article, and TEXT
- Subject:
- Saturniidae, Hyalophora cecropia, respiratory acidaemia, haemocoelic pulsations, respiratory movements, O2 consumption, spiracular pulsations, CO2 bursts, chemically produced CO2, and carbonic anhydrase
- Language:
- English
- Description:
- Discontinuous respiration in diapausing pupae of Cecropia silkworms was monitored by means of several electronic methods, including recording changes in haemocoelic pressure, monitoring respiratory movements by strain-gauge sensors and nanorespirographic recording of O2 consumption and CO2 output. It appears that, in contrast to previous concepts of stereotypic discontinuous respiration cycles (DGC) driven by accumulation of gaseous CO2 in the body, the new results indicate that CO2 remains dissolved in liquid carbonate buffers during interburst periods. In other words, there is no accumulation of gaseous CO2 within the air filled tracheal space between the bursts. The bursts of CO2 are caused by homeostatically regulated enzymatic hydration by carbonic anhydrase of metabolically produced carbonic acid. The chemically produced gaseous CO2 was exhaled mainly by a bulk outflow through selectively opened or pulsating spiracles. The output of CO2 was enhanced by actively regulated, unidirectional ventilation. The deep depressions in haemocoelic pressure, caused by permanent closure of all spiracular valves for long periods, appeared to be a specific feature of diapausing saturniid pupae. Physiologically, it has circulatory, not respiratory functions. The original definition of spiracular "fluttering" resulted from a misinterpretation of previously unknown extracardiac pulsations in haemocoelic pressure. The coordinated pulsation of the spiracular valves with extracardiac pulsations produce a very efficient, unidirectional ventilation of the whole tracheal system. According to the new results, the discontinuous respiration cycles of diapausing Cecropia pupae can be briefly described as follows: (1) Spiracular valves are kept permanently closed during the periods of deep depressions, they remain closed for some 99% of the time with occasional snap opening (passive inspirations) during prolonged interburst periods and more than 50% closed during the bursts; (2) During the long interburst periods, CO2 is retained in liquid carbonate buffers, while the relatively high (after the burst) or low (toward the next burst) rate of O2 consumption creates an internal vacuum, which is homeostatically compensated for by the snap-opening of one or just a few spiracular valves (passive suction inspirations); (3) The CO2 gas, produced enzymatically by carbonic anhydrase, enters the air filled tracheal system and leaves the body by diffusion, a bulk outflow, or actively regulated unidirectional ventilation ("fluttering" spiracles). The selective advantage of this actively regulated respiratory system for water retention in pupae is discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1648. A new look at totally positive matrices
- Creator:
- Miroslav Fiedler
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- matematika, mathematics, totally positive matrix, Monge matrix, semigroup, Vandermonde-like matrix, 13, and 51
- Language:
- English
- Description:
- A close relationship between the class of totally positive matrices and anti-Monge matrices is used for suggesting a new direction for investigating totally positive matrices. Some questions are posed and a partial answer in the case of Vandermonde-like matrices is given., Miroslav Fiedler., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1649. A new look at transudation: the apocrine connection
- Creator:
- Farkaš, Robert , Beňo, Milan , Beňová-Liszeková, Denisa , Raška, Ivan , and Raška, Otakar
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- transcellular transport, vacuolation, endosome trafficking, vesicular cargo, exocytosis, apocrine secretion, transcytosis, and transudation
- Language:
- English
- Description:
- Transcellular trafficking in which various molecules are transported across the interior of a cell, is commonly classified as transcytosis. However, historically this term has been used synonymously with transudation. In both cases transcellular trafficking starts with the internalization of proteins or other compounds on the basal or basolateral side of a cell and continues by their transport across the interior to the apical pole (or vice versa) where they are subsequently released. This allows a cell to release products which are synthesized elsewhere. Here, we discuss the common features of both transcytosis and transudation, and that which differentiates them. It appears that transcytosis and transudation are identical in terms of vesicular import and endosomal sorting of cargo, but completely differ in the re-secretion process. Specialized epithelial cells re-release substantial quantities of the endocytosed material, and often also a great variety. Some recent studies indicate that this is achieved by non-canonical apocrine secretion rather than by the regular vesicular mechanism of exocytosis, and takes place only on the apical pole. This massive re-release of endocytosed proteins, and potentially other compounds via the apocrine mechanism should be considered as transudation, distinct from transcytosis.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1650. A new method based on indirect evidences to infer activity pattern in moles. A test on the blind mole in Central Apennines
- Creator:
- Di Febbraro, Mirko and Loy, Anna
- Type:
- article, model:article, and TEXT
- Subject:
- Talpa caeca and circadian rhythms
- Language:
- English
- Description:
- The study of activity patterns in subterranean mammals has been poorly explored in subterranean insectivores. This is especially true for the rare and elusive blind mole Talpa caeca. A field work devoted to collect data on life history traits of the blind mole was run in a montane pasture in Southern Italy (1549 m a.s.l.). Plastic barrel-like traps were placed in actively used mole tunnels and checked regularly at 6 h intervals for two sessions of nine consecutive days, for a total 1500 trap-nights. No moles were captured alive, but signs of mole activity at trap sites (traps filled with ground) were regularly recorded. A video recorded inside a trap confirmed that moles fill the traps with soil as part of trap avoidance behavior. Activity at trap sites was analyzed as a binomial variable, considering the rate of filled traps vs.the number of armed traps at each 6 h trap-checking intervals. Activity showed a polyphasic pattern typical of moles, but differently from other species, activity was more concentrated in the central part of the day (12.00-18.00). Results suggest a specific adaptation to local environmental conditions and body size.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public