Welcome to Wikipedia

the free encyclopedia that anyone can edit

Picture of the Day
About Wikipedia

Picture of the Day

Thecacera pennigera, also known as the winged thecacera, is a species of sea slug in the family Polyceridae. It has a cosmopolitan distribution, being found in temperate waters on either side of the North Atlantic Ocean, in the Mediterranean Sea, around South and West Africa, Brazil, Japan, Korea, Pakistan and more recently in Australia and New Zealand. There is a significant difference in colouring between Atlantic populations and Pacific specimens, however. Thecacera pennigera has a typical adult length between 15 millimetres (0.6 in) and 30 millimetres (1.2 in), featuring a short, wide head with two lateral flaps and two sheathed olfactory organs called rhinophores. The body is wedge shaped, being wide at the front and ending in a slender foot with a lateral keel on either side. The general colour of the body is translucent white and the upper side is covered with orange splotches and small black spots. Like other sea slugs, T. pennigera is a hermaphrodite with internal fertilisation and a mating mechanism whereby pairs of animals exchange packets of sperm. This T. pennigera was photographed in the Mar Piccolo of Taranto, Italy.

Photograph credit: Roberto Strafella

Recently featured:

About Wikipedia

Wikipedia (IPA: /ˌwikiˈpiːdi.ə/ or /ˌwɪkiˈpiːdi.ə/) is a multilingual, web-based, free content encyclopedia project. Wikipedia is written collaboratively by volunteers from all around the world. With rare exceptions, its articles can be edited by anyone with access to the Internet, simply by clicking the edit this page link. The name Wikipedia is a portmanteau of the words wiki (a type of collaborative website) and encyclopedia. Since its creation in 2001, Wikipedia has grown rapidly into one of the largest reference Web sites on the Internet.

In every article, links will guide you to associated articles, often with additional information. Anyone is welcome to add further information, cross-references, or citations, so long as they do so within Wikipedia's editing policies and to an appropriate standard. One need not fear accidentally damaging Wikipedia when adding or improving information, as other editors are always around to advise or correct obvious errors, if needed, and the Wikipedia encyclopedia software, known as MediaWiki, is carefully designed to allow easy reversal of editorial mistakes.