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Leptodactylus cunicularius
Number of Pages: 5Integrative BiologyGeological Science
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Leptodactylus savagei
Number of Pages: 19Integrative BiologyGeological Science
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Leptodactylus pentadactylus
Number of Pages: 48Integrative BiologyGeological Science
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Leptodactylus syphax
Number of Pages: 9Integrative BiologyGeological Science
Symmetry, incommensurate magnetism and ferroelectricity: the case of the rare-earth manganites RMnO3
The complete irreducible co-representations of the paramagnetic space group
provide a simple and direct path to explore the symmetry restrictions of
magnetically driven ferroelectricity. The method consists of a straightforward
generalization of the method commonly used in the case of displacive modulated
systems and allows us to determine, in a simple manner, the full magnetic
symmetry of a given phase originated from a given magnetic order parameter. The
potential ferroic and magneto-electric properties of that phase can then be
established and the exact Landau free energy expansions can be derived from
general symmetry considerations. In this work, this method is applied to the
case of the orthorhombic rare-earth manganites RMnO3. This example will allow
us to stress some specific points, such as the differences between commensurate
or incommensurate magnetic phases regarding the ferroic and magnetoelectric
properties, the possible stabilization of ferroelectricity by a single
irreducible order parameter or the possible onset of a polarization oriented
parallel to the magnetic modulation. The specific example of TbMnO3 will be
considered in more detail, in order to characterize the role played by the
magneto-electric effect in the mechanism for the polarization rotation induced
by an external magnetic field.Comment: Conference: Aperiodic`0
Leptodactylus fragilis
Leptodactylus fragilis (Brocchi) White-lipped thin-toed frogs are characteristically defined according to their habitation and age. There is a diagnosis of different species group within Leptodactylus. It is furthermore described from different perspectives and discoveries such as its eggs and karyotype. The distribution of the frog is considered to be prominent occurring form Southernmost Teaxs throughout Mexico and Middle America expanding to Venezuela. The fossil fuel records and literature on Leptodactylus are slighly viewed before studying its nomenclatural history and rarity
\u3cem\u3eLeptodactylus cunicularius\u3c/em\u3e
Adult Leptodactylus cunicularius are moderately small. The head is longer than wide and the hind limbs are long (Table 1; Heyer and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are internal, not externally expanded. The snout is protruding, not sexually dimorphic. Male forearms are not hypertrophied and males lack asperities on the thumbs and chest. The dorsum is variegated with small, often confluent, spots and blotches. There is a very thin interrupted mid-dorsal light stripe (pinstripe). Usually, there is a noticeable light, irregular, elongate, mid-dorsal blotch in the scapular region. The supratympanic fold is not marked differently from the surrounding region. A weak to distinct pair of interrupted (partial or along entire length) dorsolateral folds extends from the posterior portion of the eye, passing just lateral to the sacral bones and ending in the upper groin region of the leg; the folds are usually subtly highlighted with marginally lighter stripes than the surrounding dorsal region. Another pair of interrupted, irregular dorsal folds may or may not be visible on either side of the dorsum mid-line. A pair of interrupted (along entire length) lateral folds extends from the posterior dorsal portion of the tympanic fold to the mid-groin level at the leg juncture; the folds are usually slightly lighter in color than the adjacent flanks. The toe tips are rounded, not dilated. The toes lack lateral ridges or fringes and either lack or have a trace of basal webbing between toes II-III-IV. The dorsal surface of the shank lacks tubercles and has weakly developed longitudinal folds, not differentially patterned. The posterior surface of the tarsus lacks tubercles. The sole of the foot is smooth but with small irregular light spots of the same size as light tubercles found in other species. The upper lip usually has a distinct light cream or tan stripe from just behind the snout tip, passing under the eye and tympanum and continuing through the commissural gland; if lacking, the upper lip region is homogeneously colored. The belly is cream-colored, with or without a few small tan blotches on the lateral-most extent of the belly. The posterior surface of the thigh ranges from an indistinct to a labyrinthine pattern of darker and lighter browns; usually there are a series of light dots on the lower posterior thigh where light stripes occur in other species
\u3cem\u3eLeptodactylus mystacinus\u3c/em\u3e
Adult Leptodactylus mystacinus are of moderate size, the head is as wide as long, and the hind limbs are moderately short (see Table; Heyer and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are not visible externally or at best are weakly expanded laterally and slightly darker than female throats. Male snouts are more spatulate than those of females. Male forearms are not hypertrophied. Males lack asperities on the thumbs and chest. One or two pairs of dorsolateral folds (indicated by dark/light outlining in indifferently preserved specimens) are present: one distinct more dorsal pair extends from behind the eye (often with a gap with the fold beginning at a level above the tympanum) to the upper groin; a second pair, either complete or interrupted, extends from above the forearm insertion at the same level as the dorsal portion of the supratympanic fold and extends to the groin along the flanks. The toe tips are narrow. The toes lack fringes or fleshy ridges. The upper shank has many or scattered distinct white tubercles. The outer tarsus almost always (94%) has many or scattered distinct white tubercles. The sole of the foot usually (75%) has distinct scattered to many white tubercles, sometimes (25%) the white tubercles are absent
Leptodactylus cunicularius Sazima and Bokermann Rabbit-burrow Frog
Adult Leptodactylus cunicularius are moderately small. The head is longer than wide and the hind limbs are long (Table 1; Heyer and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are internal, not externally expanded. The snout is protruding, not sexually dimorphic. Male forearms are not hypertrophied and males lack asperities on the thumbs and chest. The dorsum is variegated with small, often confluent, spots and blotches. There is a very thin interrupted mid-dorsal light stripe (pinstripe). Usually, there is a noticeable light, irregular, elongate, mid-dorsal blotch in the scapular region. The supratympanic fold is not marked differently from the surrounding region. A weak to distinct pair of interrupted (partial or along entire length) dorsolateral folds extends from the posterior portion of the eye, passing just lateral to the sacral bones and ending in the upper groin region of the leg; the folds are usually subtly highlighted with marginally lighter stripes than the surrounding dorsal region
Bibliography of the frogs of the Leptodactylus clade - Adenomera, Hydrolaetare, Leptodactylus, Lithodytes (Ampbibia, Anura, Leptodactylidae). Volume 1. References
In the funded proposal to NSF, RdS and WRH included a project to create an electronic database for all publications containing mention of species names for Adenomera, Leptodactylus, and Vanzolinius (Vanzolinius has since been synonymized with Leptodactylus). At the beginning of the project, there were about 2,000 references on 3x5 cards. Miriam H. Heyer (MHH) was contracted to create the EndNote® file. MHH entered all citations into EndNote® and examined the literature citations in those publications to determine whether any of them contained information on the genera of interest. WRH anticipated that the intensive bibliography would yield a total of 3,000 references for the genera involved. That estimate was too modest – at the end of the NSF funding for the project, 31 May 2008, we had located more than 5,000 citations. The EndNote® file of 31 May 2008 is the basis for this bibliography. About halfway through the project, the Frost et al. publication (2006) appeared. We made two decisions based on this significant work: 1) We included citations for the genera Hydrolaetare and Lithodytes. The evidence provided by Frost et al. 2006 is compelling that Adenomera, Hydrolaetare, Leptodactylus, and Lithodytes form a robust clade. 2) The relationships of Lithodytes and Adenomera as sister taxa and both genera being the sister clade to Leptodactylus has been confirmed in other primarily molecular studies. The relationships involved thus appear to be robust. We differ philosophically, not on the basis of data, with the conclusion of Frost et al. 2006 to combine Adenomera, Leptodactylus, and Lithodytes into a single genus, Leptodactylus and recognize the subgenus Lithodytes for the clade Adenomera + Lithodytes. This topic will be pursued in a future publication involving RdS, WRH, and others
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