Wikipedia
Paenibacillus is a genus of facultative anaerobic, endospore-forming bacteria, originally included within the genus Bacillus and then reclassified as a separate genus in 1993. Bacteria belonging to this genus have been detected in a variety of environments, such as: soil, water, rhizosphere, vegetable matter, forage and insect larvae, as well as clinical samples. The name reflects: Latin paene means almost, so the paenibacilli are literally "almost bacilli. The genus includes P. larvae, which is known to cause American foulbrood in honeybees, the P. polymyxa, which is capable of fixing nitrogen, so is used in agriculture and horticulture, the Paenibacillus sp. JDR-2 which is known to be a rich source of chemical agents for biotechnology applications, and pattern-forming strains such as P. vortex and P. dendritiformis discovered in the early 90s, which are known to develop complex colonies with intricate architectures as is illustrated in the pictures.
vortex colony.jpg|Picture 1: A colony generated by P. vortex sp. bacteria: The colony diameter is 5 cm and the colors indicate the bacterial density (bright yellow for high density). The bright dots are the vortices described in the text. Paenibacillus dendritiformis colony.jpg|Picture 2: A colony generated by the branching (tip splitting) morphotype bacteria of P. dendritiformis: The colony diameter is 6 cm and the colors indicate the bacterial density (darker shade for higher density). dendritiformis colony (Chiral morphotype).jpg|Picture 3: A colony generated by the chiral morphotype bacteria of P. dendritiformis: The colony diameter is 5 cm and the colors indicate the bacterial density (bright yellow for high density). Note that the branches are curly with well-defined handedness.