Gonadic cycle of Pseudechinus magellanicus (Philippi, 1857) (Echinoidea: Temnopleuridae) from Patagonia, Argentina
ZBSTRACT: Psettdecliirius tnagellanicus is one of the most abundant echinoids in Argentinean waters, r :cursing at depths from intertidal to over 150 m. It is distributed along the South American coast, from off Rio i- la Plata in the Atlantic Ocean, to Puerto Montt, in the Pacific Ocean. This speci...
Main Authors: | , , , |
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Other Authors: | , |
Format: | Book Part |
Language: | unknown |
Published: |
Taylor & Francis Group; London
2004
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Subjects: | |
Online Access: | http://hdl.handle.net/1959.4/unsworks_50403 https://unsworks.unsw.edu.au/bitstreams/a0dd52ad-1dfd-469b-9674-519ac2d465b9/download |
Summary: | ZBSTRACT: Psettdecliirius tnagellanicus is one of the most abundant echinoids in Argentinean waters, r :cursing at depths from intertidal to over 150 m. It is distributed along the South American coast, from off Rio i- la Plata in the Atlantic Ocean, to Puerto Montt, in the Pacific Ocean. This species is also found in islands of 7:: Antarctic Sea. It occupies a variety of habitats such as tide pools, mixed gravel and sand bottoms, '~crocystisb lades and Mytilus beds. Monthly samples were examined from September 2000 to March 2003. i?ecimens were collected by scuba diving from depths of 6-10 m in Golfo Nuevo, Puerto Mad~ynG. onad index - 2s analyzed monthly. There are two reproductive peaks and partial spawning events throughout the year. Major ;-wnings were recorded in late winter (June-August) corresponding to the minimum winter water temperature .-9°C) and an increase in day length, and in summer (January- February), corresponding to the highest water s-aperature value (17-18OC) and maximum day lengths. These observations were corroborated by analysis -m'i croscopic changes in gonads and in the distribution of oocyte sizes in the ovary. Males recover faster -Y females, being able to spawn during ahnost the whole year. Resorption after spawning was observed in : -3 sexes. Oocytes bigger than 105 km have a jelly coat of 10-12 p,m which could protect them after released -I ::?e water. |
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