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Boring sponges

Cliona celata

Cliona celata is a yellow to orange excavating (or boring) sponge, occurring in two distinct forms. One is the boring form, recognizable as yellow papillae sticking out of limestone (calcareous rocks, shells, etc.); the other is a massive, wall-shaped sponge covered with characteristic flattened papillae. The massive form often forms a thick plate-like structure standing on its edge, up to 1 m across and 25 cm thick. The massive form is very common around the west coasts of Britain and France. The boring form is very common in oyster and mussel beds, where they cause damage to shellfish farming.

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Sea Grapes

Molgula manhattensis

Molgula manhattensis is a greenish-olive or yellowish-green grape-like rounded solitary tunicate, sometimes laterally flattened, with a globular body shape. The tunic is firm, tough and moderately thick. Some areas on the tunic may develop into small hair-like projections called papillae which frequently catch and accumulate particles or organisms to its tunic and siphons. The two siphons are fairly close together at the anterior end. Large specimens of M. manhattensis can measure 20 -50 mm in length and height.

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Chain tunicate

Botrylloides violaceus

Botrylloides violaceus is a thin and lobe-like colonial tunicate with zooids that form long double rows or ladder-like chains. When the chains are short, they sometimes look similar to the flower-like pattern observed in Botryllus schlosseri. Color variations in colonies range from red, yellow, orange, brown, purple and light lavender. Like other colonial tunicates, the B. violaceus colonies are encrusting, with a thickness of 2 – 3 mm, and can be as large as 200 mm × 20 mm. The tunic protecting the zooids is soft and can be easily torn.

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Asian Stalked Tunicate

Styela clava

Styela clava is a solitary tunicate with a leathery, but thin, and bumpy tunic. Its body is cylindrical or club-shaped and narrows posteriorly to a stalk that is anchored to the substrata by a disk shaped holdfast. The wrinkled or creased looking stalk is often 20-50% of the total body length. Styela clava can grow up to 150 mm in length. Colors can range from yellowish to reddish to brownish. The oral and atrial siphons are located close together and are directed anteriorly. Both siphons have four lobes and appear striped with alternating dark and light brownish to purplish bands. It is native to the Northwest Pacific, from Shanghai to the Sea of Okhotsk and the Southeastern Bering Sea and has been introduced to both coasts of North America and to Europe, Australia and New Zealand.

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Carpet sea squirt

Didemnum vexillum

Didemnum vexillum is an aggressive and rapidly spreading colonial tunicate that forms yellowish-cream extensive thin sheets, which overgrow and encrust rocks, wood, ropes, shells and/or other structures, as well as other organisms such as hydroids, sponges and oysters. It also encrusts itself as it forms large sponge-like-masses that have flexible leaf or flag like projections. As such, the colonies may appear to be folding in on themselves and neighboring surfaces. Didemnum vexillum is believed to have originated from the Northwest Pacific, probably Japan, but has been also reported in other parts of the world such as Europe, North America and New Zealand.

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White colonial sea squirt

Didemnum perlucidum

Didemnum perlucidum is a widely distributed colonial tunicate that is believed to be native to tropical Indo-Pacific waters. Colonial tunicates are communities of individuals, called zooids, which share a protective layer called a tunic. Although considered cryptogenic, D. perlucidum was first described in the Caribbean and later found in West Africa, Indo-Pacific (including Panama Canal, Guam and Hawaii), Brazil and the Gulf of Mexico, where it has colonized harbors, rock, wood, rope and other man-made structures. The colonies have a marble appearance, showing varying colors, including white and gray, yellow, or brown - with the darker color due to fecal pellets. The largest D. perlucidum colonies measure 8 cm but are only 1-3 mm thick.

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Saffron finch

Sicalis flaveola

Saffron finches are garden birds throughout their native range, and they are also a common pet bird. They're difficult for the untrained eye but females usually have darker and more pronounced black streaking on the back, and are slightly smaller than males.

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Common redpoll

Carduelis flammea

The common redpoll is a small brownish-grey finch with dark streaks and a bright red patch on its forehead. It has a black bib and two pale stripes on the wings. They are primarily seed-eaters, and often feed acrobatically.

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African clawed toad

Xenopus laevis

The African clawed frog is a species of African aquatic frog. They are voracious predators and easily adapt to many habitats. They have been shown to devastate native populations of frogs and other creatures by eating their young.

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Varroa mite

Varroa destructor

Varroa mites are external honey bee parasites that attack both the adults and the brood, with a distinct preference for drone brood. It was first found in South Africa in August 1997, the first report of this mite in sub-Saharan Africa. An immediate survey revealed that the mite was common and widespread in both commercial and wild honeybee populations in the Western Cape, but absent from the rest of the country.

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