Lumbriculus - Lumbriculus Variegatus, Lumbriculus Genitosetosus, Lumbriculus Illex, Lumbriculus Ambiguus, Lumbriculus Kareliensis (Paperback)

Chapters: Lumbriculus Variegatus, Lumbriculus Genitosetosus, Lumbriculus Illex, Lumbriculus Ambiguus, Lumbriculus Kareliensis, Lumbriculus Multiatriatus, Lumbriculus Japonicus, Lumbriculus Mukoensis. Source: Wikipedia. Pages: 25. Not illustrated. Free updates online. Purchase includes a free trial membership in the publisher's book club where you can select from more than a million books without charge. Excerpt: Lumbriculus variegatus, sometimes known as blackworm (or even California blackworm), is the name given to at least three distinct species of worms which are identical in outward appearance. Until 2009, the species were regarded as one. These species of worms live in shallow water marshes, ponds, and swamps, feeding on microorganisms and organic material. They live throughout North America and Europe. On average, an adult blackworm can have from 150 segments to 250, each of which has the ability to regenerate into a whole new individual when separated from the rest of the animal; in most populations, this is the primary mode of reproduction, and sexually mature individuals are exceedingly rare - in large areas (including Asia, most of North America and the greater part of Europe) sexually mature individuals have never been found. Among the characteristics of the genus are a green pigmentation of the anterior end, its two-pointed setae, and its curious reflex escape mechanisms. When touched, Lumbriculus will attempt to escape, either by swimming in a helical ("cork-screw") fashion, or by reversing its body. Which of these two escape patterns are used, depends on where the worm is touched: the anterior end elicits body reversal, and the posterior end helical swimming. Lumbriculus has a quick reflex that allows it to use its photoreceptors to escape. The photoreceptors can detect shadows and movement. The posterior end lifts out of the water and forms a right angle. It is then exposed to air and is used to exchange oxyg...More: http: //booksllc.net/?id=278911