Shell standing in Planaxis sulcatus: convergence of heat avoidance behavior in rocky shore gastropods?

Author(s):  
David J Marshall

Shell standing behavior, which allows snails living in the hottest upper rocky shore zones to avoid overheating, is reported here for the first time in a nonlittorinid snail. This was observed in Planaxis sulcatus which cohabits with the littorinid Echinolittorina malaccana, suggesting convergence of this behavioral trait.

2017 ◽  
Vol 22 (10) ◽  
pp. 1639
Author(s):  
Jhih-Rong Liao ◽  
Chyi-Chen Ho ◽  
Chiun-Cheng Ko

Phytoseiid mites have been intensively surveyed in Taiwan during the past decades because of their potential as biological control agent. Despite the fact, many regions of Taiwan remain under-explored especially in mountain areas and neighboring islands. Typhlodromus (Anthoseius) crossostephium sp. nov. was collected from Crossostephium chinense (L.) Makino (Asteraceae) on rocky shore habitat during a survey on Lanyu Island. In this paper, presence of a phytoseiid mite on rocky shores is reported for the first time. A detailed morphological description of the new species and a key to the Taiwanese species of subgenus Anthoseius are provided.


2021 ◽  
Vol 133 (2) ◽  
pp. 57
Author(s):  
Jeffrey H. Robinson

A Late Oligocene rocky shore fauna from Cosy Dell farm, Southland, is shown to include six brachiopod genera and species and, for the first time, records the co-existence of a discinid, a craniid and a kraussinid in such a paleoecological setting in New Zealand. This study includes the first reported occurrence of Discradisca in New Zealand and extends the stratigraphic range of species Megerlina miracula Hiller, MacKinnon & Nielsen, 2008 back to the late Oligocene. In addition, this study confirms the occurrence of M. miracula in very shallow-water deposits.


Zootaxa ◽  
2021 ◽  
Vol 4990 (3) ◽  
pp. 563-570
Author(s):  
LORENZO MUNARI ◽  
ASHLEY H. KIRK-SPRIGGS ◽  
GILLIAN K. MCGREGOR

A survey of the surf flies (Canacinae) of the main Mascarene Islands of La Réunion, Mauritius, and Rodrigues was undertaken between 2015 and 2018. It encompassed intertidal material from 38 sampling stations on the islands and included records supplied by Martin J. Ebejer from La Réunion. No specimens of surf flies were collected on Rodrigues Is., which lacks suitable rocky shore habitats. A new species of Isocanace Mathis, 1982, that is deemed closely related to I. briani Mathis, 1982 described from Aldabra Is. and Madagascar, is described and figured from Mauritius (I. mauritiana Munari sp. nov.). Nocticanace mahensis (Lamb, 1912) is also reported from La Réunion and Mauritius and Procanace pninae Mathis & Freidberg, 1991 from Mauritius (all representing first records for the islands concerned). The Procanace grisescens species-group is also reported from Mauritius for the first time, representing a first record of this species-group from the Mascarenes. An identification key to Afrotropical species of Isocanace is provided and the distributions of all species are mapped.  


2013 ◽  
Vol 93 (6) ◽  
pp. 1511-1524 ◽  
Author(s):  
Barbara Mikac ◽  
Adriana Giangrande ◽  
Margherita Licciano

Sabellidae is the second most diverse polychaete family in the Adriatic Sea, after Syllidae. Herein we report the updated list of the Sabellidae and Fabriciidae families in the Adriatic Sea deriving both from literature data and presently conducted researches in the northern Adriatic. During these researches polychaetes were sampled from three offshore soft-bottom and three coastal rocky shore stations. Among the analysed material three Sabellidae species are new records for the Adriatic fauna, while four Sabellidae and one Fabriciidae species were recorded for the first time in the northern part. Two new species were found and described: Amphicorina rovignensis spec. nov. and Megalomma pseudogesae spec. nov. These findings increase the number of Sabellidae taxa recorded in the northern Adriatic from 29 to 38. Our results point out the lack of the recent taxonomic studies in the area, but might also indicate the widening of the species areal. Taking into consideration that studies on only six stations raised the number of known sabellid taxa from the area by 31%, our results support the need for the regular taxonomic updating of the polychaete fauna in the northern Adriatic.


Stress ◽  
2020 ◽  
Vol 23 (5) ◽  
pp. 567-576
Author(s):  
Katja Petrowski ◽  
Susann Wichmann ◽  
Jaroslav Pyrc ◽  
Susann Steudte-Schmiedgen ◽  
Clemens Kirschbaum

Author(s):  
J. Chakraborty ◽  
A. P. Sinha Hikim ◽  
J. S. Jhunjhunwala

Although the presence of annulate lamellae was noted in many cell types, including the rat spermatogenic cells, this structure was never reported in the Sertoli cells of any rodent species. The present report is based on a part of our project on the effect of torsion of the spermatic cord to the contralateral testis. This paper describes for the first time, the fine structural details of the annulate lamellae in the Sertoli cells of damaged testis from guinea pigs.One side of the spermatic cord of each of six Hartly strain adult guinea pigs was surgically twisted (540°) under pentobarbital anesthesia (1). Four months after induction of torsion, animals were sacrificed, testes were excised and processed for the light and electron microscopic investigations. In the damaged testis, the majority of seminiferous tubule contained a layer of Sertoli cells with occasional spermatogonia (Fig. 1). Nuclei of these Sertoli cells were highly pleomorphic and contained small chromatinic clumps adjacent to the inner aspect of the nuclear envelope (Fig. 2).


Author(s):  
M. Rühle ◽  
J. Mayer ◽  
J.C.H. Spence ◽  
J. Bihr ◽  
W. Probst ◽  
...  

A new Zeiss TEM with an imaging Omega filter is a fully digitized, side-entry, 120 kV TEM/STEM instrument for materials science. The machine possesses an Omega magnetic imaging energy filter (see Fig. 1) placed between the third and fourth projector lens. Lanio designed the filter and a prototype was built at the Fritz-Haber-Institut in Berlin, Germany. The imaging magnetic filter allows energy-filtered images or diffraction patterns to be recorded without scanning using efficient area detection. The energy dispersion at the exit slit (Fig. 1) results in ∼ 1.5 μm/eV which allows imaging with energy windows of ≤ 10 eV. The smallest probe size of the microscope is 1.6 nm and the Koehler illumination system is used for the first time in a TEM. Serial recording of EELS spectra with a resolution < 1 eV is possible. The digital control allows X,Y,Z coordinates and tilt settings to be stored and later recalled.


Author(s):  
Z.L. Wang ◽  
J. Bentley ◽  
R.E. Clausing ◽  
L. Heatherly ◽  
L.L. Horton

Microstructural studies by transmission electron microscopy (TEM) of diamond films grown by chemical vapor deposition (CVD) usually involve tedious specimen preparation. This process has been avoided with a technique that is described in this paper. For the first time, thick as-grown diamond films have been examined directly in a conventional TEM without thinning. With this technique, the important microstructures near the growth surface have been characterized. An as-grown diamond film was fractured on a plane containing the growth direction. It took about 5 min to prepare a sample. For TEM examination, the film was tilted about 30-45° (see Fig. 1). Microstructures of the diamond grains on the top edge of the growth face can be characterized directly by transmitted electron bright-field (BF) and dark-field (DF) images and diffraction patterns.


Author(s):  
Shou-kong Fan

Transmission and analytical electron microscopic studies of scale microstructures and microscopic marker experiments have been carried out in order to determine the transport mechanism in the oxidation of Ni-Al alloy. According to the classical theory, the oxidation of nickel takes place by transport of Ni cations across the scale forming new oxide at the scale/gas interface. Any markers deposited on the Ni surface are expected to remain at the scale/metal interface after oxidation. This investigation using TEM transverse section techniques and deposited microscopic markers shows a different result,which indicates that a considerable amount of oxygen was transported inward. This is the first time that such fine-scale markers have been coupled with high resolution characterization instruments such as TEM/STEM to provide detailed information about evolution of oxide scale microstructure.


Author(s):  
Yimei Zhu ◽  
J. Tafto

The electron holes confined to the CuO2-plane are the charge carriers in high-temperature superconductors, and thus, the distribution of charge plays a key role in determining their superconducting properties. While it has been known for a long time that in principle, electron diffraction at low angles is very sensitive to charge transfer, we, for the first time, show that under a proper TEM imaging condition, it is possible to directly image charge in crystals with a large unit cell. We apply this new way of studying charge distribution to the technologically important Bi2Sr2Ca1Cu2O8+δ superconductors.Charged particles interact with the electrostatic potential, and thus, for small scattering angles, the incident particle sees a nuclei that is screened by the electron cloud. Hence, the scattering amplitude mainly is determined by the net charge of the ion. Comparing with the high Z neutral Bi atom, we note that the scattering amplitude of the hole or an electron is larger at small scattering angles. This is in stark contrast to the displacements which contribute negligibly to the electron diffraction pattern at small angles because of the short g-vectors.


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