NOTES ON AN ARTIFICIAL ROOST OF Myotis albescens (CHIROPTERA, VESPERTILIONIDAE) IN SOUTHEASTERN BRAZIL

Myotis albescens has a wide distribution, occurring from southern Mexico to central Argentina and Uruguay, where it is usually caught near streams or flooded areas. M. albescens roosts during the day in cavities such as hollow logs, rock cavities, and buildings. Here, we describe a group of M. albescens roosting in a highway underpass in an Atlantic Forest area in Rancharia, southeastern Brazil. The group was found inside a culvert with a shallow stream passing through it. The animals left the roost and were mist-netted in the first hours of the night. The M. albescens group was composed of 18 individuals, eleven males and seven females. In October, all males had descended testes and two females were pregnant, as confirmed by abdominal palpation. Morphological characters of the specimens fell in the known variation for the species. Our data show that highway underpasses can be important day roosts for bats, especially if riparian areas are preserved

icepack: a new glacier flow modeling package in Python, version 1.0

We introduce a new software package called “icepack” for modeling the flow of glaciers and ice sheets. The icepack package is built on the finite element modeling library Firedrake, which uses the Unified Form Language (UFL), a domain-specific language embedded into Python for describing weak forms of partial differential equations. The diagnostic models in icepack are formulated through action principles that are specified in UFL. The components of each action functional can be substituted for different forms of the user's choosing, which makes it easy to experiment with the model physics. The action functional itself can be used to define a solver convergence criterion that is independent of the mesh and requires little tuning on the part of the user. The icepack package includes the 2D shallow ice and shallow stream models. We have also defined a 3D hybrid model based on spectral semi-discretization of the Blatter–Pattyn equations. Finally, icepack includes a Gauss–Newton solver for inverse problems that runs substantially faster than the Broyden–Fletcher–Goldfarb–Shanno (BFGS) method often used in the glaciological literature. The overall design philosophy of icepack is to be as usable as possible for a wide a swath of the glaciological community, including both experts and novices in computational science.

Treatment of ice-shelf evolution combining flow and flexure

We develop a two-dimensional, plan-view formulation of ice-shelf flow and viscoelastic ice-shelf flexure. This formulation combines, for the first time, the shallow-shelf approximation for horizontal ice-shelf flow (and shallow-stream approximation for flow on lubricated beds such as where ice rises and rumples form), with the treatment of a thin-plate flexure. We demonstrate the treatment by performing two finite-element simulations: one of the relict pedestalled lake features that exist on some debris-covered ice shelves due to strong heterogeneity in surface ablation, and the other of ice rumpling in the grounding zone of an ice rise. The proposed treatment opens new venues to investigate physical processes that require coupling between the longitudinal deformation and vertical flexure, for instance, the effects of surface melting and supraglacial lakes on ice shelves, interactions with the sea swell, and many others.

<i>icepack</i>: a new glacier flow modeling package in Python, version 1.0

We introduce a new software package called icepack for modeling the flow of glaciers and ice sheets. Icepack is built on the finite element modeling library Firedrake, which uses the domain-specific language UFL for describing weak forms of partial differential equations. The diagnostic models in icepack are formulated through action principles that are specified in UFL. The components of each action functional can be substituted for different forms of the user’s choosing, which makes it easy to experiment with the model physics. The action functional itself can be used to define a solver convergence criterion that is independent of the mesh and requires little tuning on the part of the user. Icepack includes the 2D shallow ice and shallow stream models. We have also defined a 3D hybrid model based on spectral semi-discretization of the Blatter-Pattyn equations. Finally, icepack includes a Gauss-Newton solver for inverse problems that runs substantially faster than the BFGS method often used in the glaciological literature. The overall design philosophy of icepack is to be as usable as possible for a wide a swath of the glaciological community, including both experts and novices in computational science.

On the verge of extinction in Mexico today: Field observations of Ambystoma ordinarium and Ambystoma flavipiperatum with remarks on their habitat and conservation

Mexico is a hotspot of salamander diversity and harbours 18 species of the genus Ambystoma (Amphibia: Urodela) widely distributed from the Sierra Madre Occidental to the Trans-Mexican Volcanic Belt. These species are highly threatened by various factors and some of them are considered nearly extinct in the wild. The Michoacán stream salamander, Ambystoma ordinarium and the yellow-peppered salamander, A. flavipiperatum are two endemic and scarce species from Mexico living in isolated and declining populations. Few observations have been made on them in their natural habitat since their original description. Here we report new data regarding the biology and habitats of A. ordinarium observed at Rio Bello, 2,120 m a.s.l., Morelia city, Michoacán state, and for A. flavipiperatum at Sierra de Quila, 2,165 m a.s.l., 100 km south from Guadalajara city, Jalisco state. For A. ordinarium we found one neotenic adult male and two dead adult females in a small shallow stream located within a fragmented fir, oak and pine forest. For A. flavipiperatum we recorded an adult male and a female both neotenic, one clutch of eggs, and eleven larvae inhabiting a slow-moving stream located through a riparian habitat surrounded by large pineoak forest. Our observations confirm that both species are highly endangered, capable of facultative neoteny and occur in small slow-moving streams surrounded by coniferous forests. We discuss their morphology, geographical distribution and conservation status.

Mallomonas cronbergiae (Chrysophyceae, Stramenopiles), A New Species from the Guineo-Congolian Rainforest in Cameroon

A new species of Mallomonas Perty, M. cronbergiae J. Piątek sp. nov., was found in a tropical shallow stream pool in the Guineo-Congolian rainforest in Cameroon. It belongs to the series Ouradiotae and is similar to the three other Mallomonas taxa from this series, namely M. ouradion Harris & Bradley, M. parvula Dürrschmidt and M. parvula var. nichollsii Wujek & Bland, but differs in some morphological characters that clearly differentiate M. cronbergiae as a distinct species. The new species has a different size of scales, characteristic 3–7 pores at the posterior rim, an anterior flange ornamented with papillae, and a shield thickly ornamented with papillae (14–16 per scale width). The species is described and illustrated with the use of light and scanning electron microscopy.