scholarly journals Bioluminescence induction in the ophiuroid Amphiura filiformis (Echinodermata)

2020 ◽  
Vol 223 (4) ◽  
pp. jeb218719 ◽  
Author(s):  
Jerome Mallefet ◽  
Laurent Duchatelet ◽  
Constance Coubris
Keyword(s):  
Amphiura Filiformis

scholarly journals The influence of hypercapnia and the infaunal brittlestar <i>Amphiura filiformis</i> on sediment nutrient flux – will ocean acidification affect nutrient exchange?

2009 ◽  
Vol 6 (10) ◽  
pp. 2015-2024 ◽  
Author(s):  
H. L. Wood ◽  
S. Widdicombe ◽  
J. I. Spicer
Keyword(s):  
Atmospheric Carbon Dioxide ◽  
Marine Invertebrates ◽  
Nutrient Flux ◽  
Additional Treatment ◽  
Direct Effects ◽  
Exposure Study ◽  
Physicochemical Changes ◽  
Amphiura Filiformis ◽  
The Impact

Abstract. Rising levels of atmospheric carbon dioxide and the concomitant increased uptake of this by the oceans is resulting in hypercapnia-related reduction of ocean pH. Research focussed on the direct effects of these physicochemical changes on marine invertebrates has begun to improve our understanding of impacts at the level of individual physiologies. However, CO2-related impairment of organisms' contribution to ecological or ecosystem processes has barely been addressed. The burrowing ophiuroid Amphiura filiformis, which has a physiology that makes it susceptible to reduced pH, plays a key role in sediment nutrient cycling by mixing and irrigating the sediment, a process known as bioturbation. Here we investigate the role of A. filiformis in modifying nutrient flux rates across the sediment-water boundary and the impact of CO2- related acidification on this process. A 40 day exposure study was conducted under predicted pH scenarios from the years 2100 (pH 7.7) and 2300 (pH 7.3), plus an additional treatment of pH 6.8. This study demonstrated strong relationships between A. filiformis density and cycling of some nutrients;

Ultrastructure of the podia of Amphiura chiajei and Amphiura filiformis and their role in feeding

2006 ◽  
Vol 86 (4) ◽  
pp. 817-822 ◽  
Author(s):  
John K. Keogh ◽  
Brendan F. Keegan
Keyword(s):  
Chemical Composition ◽  
Morphological Study ◽  
Secretory Cells ◽  
Suspension Feeding ◽  
Head Region ◽  
Feeding Styles ◽  
Amphiura Filiformis ◽  
The Difference ◽  
Mucus Cells ◽  
Deposit Feeding

Morphological study of the podia of the suspension feeding Amphiura filiformis and the deposit feeding Amphiura chiajei revealed sensory–secretory complexes in the podial epidermis, consisting of four cells, two secretory and two sensory. Large mucus cells were found in association, but not exclusively, with the sensory–secretory complexes. In A. filiformis, mucus cells stained positively for both acid and neutral mucopolysaccharides, while, in A. chiajei, these cells stained only for acid mucopolysaccharides. The surfaces of the arm podia in A. chiajei were relatively smooth, while the arm podia of A. filiformis bear papillae. The sensory–secretory complexes open through numerous paired pores, with each pair having an intervening cilium. Pores were restricted to the podial tip in A. chiajei, while in A. filiformis they are concentrated on the podial tip and on the papillae. Amphiura chiajei shows very little differentiation of the podia along the length of the arm. In A. filiformis, the distal podia have papillae throughout their entire length, with pores being found on the head region and the papillar tips. Here, the papillae are oriented in such a way (i.e. facing inward towards the ventral arm plate) as to increase the area of the filtering surface of the podium, serviced by the sticky secretions from the sensory–secretory complexes. The proximal podia are relatively simple in structure and are thought to function more in the transportation of mucus wrapped particles to the mouth rather than in their capture. The difference in structure of the podia and chemical composition of podial secretory cells are taken to reflect the difference in feeding styles of the two species.

Intrinsic gene expression during regeneration in arm explants of Amphiura filiformis

2012 ◽  
Vol 413 ◽  
pp. 106-112 ◽  
Author(s):  
Gavin Burns ◽  
Olga Ortega-Martinez ◽  
Samuel Dupont ◽  
Michael C. Thorndyke ◽  
Lloyd S. Peck ◽  
...  
Keyword(s):  
Gene Expression ◽  
Intrinsic Gene ◽  
Amphiura Filiformis
Sign in / Sign up

Export Citation Format

Share Document