Brief Descriptions of 5 US South Atlantic Octopuses @Octo Girl created a Facebook post to help identify the species she has observed during her research on the East Coast of Florida. With her permission, I am copying the post below: Octopuses at the Bridge! The question was asked- "What species are at the bridge and how do we tell them apart?" Right now I have a count of 5 octopus species found at the bridge!! The two most commonly seen/found there are Macrotritopus defilippi and Octopus vulgaris (the two species I am doing research on). I have provided a detailed description below of all 5 species and pictures. Sorry this post is long wink emoticon Thanks to Sandra Edwards, David Sanchez and Rachel Plunkett for the pictures and Joey Maier for the question! Please post and let me know if you have seen another species at the bridge! Five octopus species at the bridge: Macrotritopus defilippi- commonly known as the Atlantic long arm or mimic octopus. Primary habitat is sand. Distinguishing body pattern: Transverse arm bars, heart shaped pattern on mantle, and very long arms! Distinguishing skin features-widespread dark flecks of mottle, distinctive white round spots along arms and one on mantle near eyes, no reddish coloration (what you see in O. vulgaris), single white spot on extreme anterior mantle. Distinguishing behavior: floundering (in picture), crawl across open substrate with long arms spread radially presumably hunting prey , can easily bury directly into substrate. Reported do be nocturnal and diurnal. I have observed this species active during mid-late afternoon. Octopus monitoring device will tell us more info soon! Octopus vulgaris- known as the common octopus. Primary habitat – coral reef and sand-seagrass. Can bury in sand. Type of den- hole in hard substrate-littered with shells (see picture). Most distinguishing body pattern feature: highly variable patterns mottle (see picture). Distinguishing skin features- patch and groove trellis arrangement, distinct frontal white spots. Very wide range of body patterns. Reported to be nocturnal and diurnal. Octopus burryi- commonly known as the brownstripe octopus or the Caribbean armstripe octopus. Primary habitat: sand flats near reef. Similar patterns to O. vulgaris. Distinguishing body pattern features: grained skin texture (distinguishing characteristic of species), acute mottle with longitudinal arm stripes (diagnostic character of this species, see picture). Reported to be nocturnal. Octopus hummelincki (also referred to as Octopus filosus)- commonly known as the Caribbean two spot octopus. Primary habitat: shallow water on reefs . Most distinguishing body pattern features: Ocelli (blue rings which create false eye markings) between eye and 2nd/ 3rd arms (see pictures). Distinguishing skin features: ocelli, patch and groove trellis arrangement, diffuse frontal white spots, 2 large mantle white spots, similar patterns to O. vulgaris, but ocelli separate the two species. No reported activity time. Octopus briareus- commonly known as the Caribbean reef octopus. Primary habitat: coral reef. Most distinguishing body pattern: green/blue iridescence and extensive web spread (see picture). Den: usually hole in reef or sponge. Distinguishing behaviors speculative parachute attack maneuver (see picture).