307 research outputs found
A new subspecies of Cymothoe fumana (Westwood, 1850) from Western Nigeria (Lepidoptera : Nymphalidae : Limenitidinae)
New taxa of pronophiline butterflies of the genus Lymanopoda Westwood from Ecuador (Lepidoptera: Nymphalidae: Satyrinae)
Mauritius butterflies revisited : short faunal survey reveals a new record for the Mascarene fauna : Leptotes jeanneli (Stempffer)
Discovery of a remarkable new species of Lymanopoda (Lepidoptera : Nymphalidae : Satyrinae) and considerations of its phylogenetic position : an integrative taxonomic approach
The Presence–Absence Situation and Its Impact on the Assemblage Structure and Interspecific Relations of Pronophilina Butterflies in the Venezuelan Andes (Lepidoptera: Nymphalidae)
Assemblage structure and altitudinal patterns of Pronophilina, a species-rich group of Andean butterflies, are compared in El Baho and Monte Zerpa, two closely situated and ecologically similar Andean localities. Their faunas differ only by the absence of Pedaliodes ornata Grose-Smith in El Baho. There are, however, important structural differences between the two Pronophilina assemblages. Whereas there are five co-dominant species in Monte Zerpa, including P. ornata, Pedaliodes minabilis Pyrcz is the only dominant with more than half of all the individuals in the sample in El Baho. The absence of P. ornata in El Baho is investigated from historical, geographic, and ecological perspectives exploring the factors responsible for its possible extinction including climate change, mass dying out of host plants, and competitive exclusion. Although competitive exclusion between P. ornata and P. minabilis is a plausible mechanism, considered that their ecological niches overlap, which suggests a limiting influence on each other’s populations, the object of competition was not identified, and the reason of the absence of P. ornata in El Baho could not be established. The role of spatial interference related to imperfect sexual behavioral isolation is evaluated in maintaining the parapatric altitudinal distributions of three pairs of phenotypically similar and related species of Pedaliodes, Corades, and Lymanopoda
Revalidation of Pedaliodes lithochalcis BUTLER & DRUCE, description of a new species from Peru and Bolivia and of a new subspecies of P. napaea BATES from Honduras (Lepidoptera : Nymphalidae : Satyrinae)
Pedaliodes lithochalcis, occurring in Costa Rica and Panama, has been considered for more than a century a junior synonym of P. dejecta from Guatemala. It is reinstated here as a valid species. It is shown that the two species belong to different groups of species with sympatric representatives throughout Central America and the Andes characterized by common characters of adult morphology, particularly the male genitalia. Pedaliodes lithochalcis is closely related to P. napaea whose new subspecies, P. napaea naksi n. ssp., is described from the Celaque massif in Honduras. It is the first cloud forest Satyrinae butterfly described from this country. Pedaliodes dejecta is related to another Mesoamerican species, P. ereiba, and to P. pomponia from Ecuador and to a new species, P. peregrina n. sp., from Peru and Bolivia
Considerations on the taxonomy of the genus Arhuaco Adams and Bernard 1977, and its relationships with the genus Pronophila Doubleday [1849] (Nymphalidae, Satyrinae)
A new Andean element in the lepidopterous fauna of the Guiana Shield : the day-flying genus Erateina Doubleday, with the description of two new species from Roraima, Tramen and Auyán Tepui (Geometridae: Larentiinae)
Rigid Transformations for Stabilized Lower Dimensional Space to Support Subsurface Uncertainty Quantification and Interpretation
Subsurface datasets inherently possess big data characteristics such as vast
volume, diverse features, and high sampling speeds, further compounded by the
curse of dimensionality from various physical, engineering, and geological
inputs. Among the existing dimensionality reduction (DR) methods, nonlinear
dimensionality reduction (NDR) methods, especially Metric-multidimensional
scaling (MDS), are preferred for subsurface datasets due to their inherent
complexity. While MDS retains intrinsic data structure and quantifies
uncertainty, its limitations include unstabilized unique solutions invariant to
Euclidean transformations and an absence of out-of-sample points (OOSP)
extension. To enhance subsurface inferential and machine learning workflows,
datasets must be transformed into stable, reduced-dimension representations
that accommodate OOSP.
Our solution employs rigid transformations for a stabilized Euclidean
invariant representation for LDS. By computing an MDS input dissimilarity
matrix, and applying rigid transformations on multiple realizations, we ensure
transformation invariance and integrate OOSP. This process leverages a convex
hull algorithm and incorporates loss function and normalized stress for
distortion quantification. We validate our approach with synthetic data,
varying distance metrics, and real-world wells from the Duvernay Formation.
Results confirm our method's efficacy in achieving consistent LDS
representations. Furthermore, our proposed "stress ratio" (SR) metric provides
insight into uncertainty, beneficial for model adjustments and inferential
analysis. Consequently, our workflow promises enhanced repeatability and
comparability in NDR for subsurface energy resource engineering and associated
big data workflows.Comment: 30 pages, 17 figures, Submitted to Computational Geosciences Journa
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