Cryptogenic Species - Descriptions

Click here for Introduced Species Descriptions.
Click here to return to the intro page.

Protista (Single-cell organisms)

Foraminfera sp.
Common Name: Forminiferans
Foraminfera are a class of protists that encompass many species. At this time it is unclear which species are present in the North Atlantic.

Zoothamnium sp.
Common Name:
Zoothamnium is a genus of ciliated protozoans. At this time it is unclear which species is present in the Northeast.

Porifera (Sponges)

Leucosolenia sp.
Common Name: Sponge
Some sponges in this genus are introduced, cryptogenic, or native. Until further identification it has been listed as cryptogenic.

Scypha sp.
Common Name: Sponge
This is a vase-like sponge. Some sponges in this genus are introduced, cryptogenic, or native. Until further identification it has been listed as cryptogenic.

Cnidaria (Hydroids, Anemones and Jellyfish)

Hydrozoa

Descriptions taken from information provided by Dr. Dale Calder, Royal Ontario Museum and A Practical Guide to the Marine Animals of Northeastern North America by Leland Pollack (1997). The origins of these hydroids are unknown. They are attached and could easily have been transported by ship fouling or solid ballast (rocks and shale) commonly used until the 1900s.

Campanularia sp.
Common Name: Hydroid
Hydroids are small colonial animals that are often confused as plants. They grow as attached bushy growths on pilings, rocks, seaweeds and other benthic strata. The individual hydroid animals or zooids, are composed of a stem-like pedicel and a flower-like hydranth, which usually contains a central mouth and tentacles.

Dynamena pumila
Common Name: Sea Oak Hydroid
This is a stiff colonial hydroid, tannish in color, and branching in a single plane. It is abundant in the lower intertidal regions and grows on fucoids and rocks. Its earliest record was in the Gulf of St. Lawrence and it now ranges south to New Jersey. See general hydroid comments above.

Clytia hemisphaerica
Common Name: Hydroid
This small, whitish colonial, and generally inconspicuous hydroid was first recorded in South Carolina as Campanularia noliformis. It ranges from the Gulf of St. Lawrence to Brazil. See general hydroid comments above.

Ectopleura larynx (formerly Tubularia larynx)
Common Name: Hydroid
This ringed tubularian has a pink hydranth (anemone-like structure) that grows on a colorless stalk. It can be very abundant locally during the earlier part of the summer. It ranges from the Gulf of St. Lawrence to southern New England. See general hydroid comments above.

Gonothyraea loveni
Common Name: Hydroid
This hydroid may be very abundant in estuarine conditions. It ranges from the Arctic to South Carolina. See general hydroid comments above.

Halecium halecinum
Common Name: Hydroid
Colonies vary in shape, but usually consist of a straight main stem, with secondary straight branches and tertiary branches bearing polyps. These branch at approximately 50 degrees to and in the same plane as the stem from which they arise. The polyps are only partially retracted into cylindrical thecae which have out-turned rims. Colonies typically 50-100mm in height.

Laomedea calceolifera (formerly known as Campularia calceolifera)
Common Name: Hydroid
This hydroid can be found growing on pilings, mussels, algae and other hard surfaces. It is very abundant in the shallow waters of southern New England with a range extending from Maine to Long Island Sound. See general hydroid comments above.

Obelia bidentata
Common Name: Hydroid
This hydroid has a hard covering called a thecate that is toothed at the opening for the hydranth (anemone-like structure). It can be commonly abundant, especially in estuarine conditions and ranges from Maine to Brazil. See general hydroid comments above.

Obelia dichotoma
Common Name: Sea Threadhydroid
This is a stalked hydroid that tends to grow vertically with very little branching. It is easily confused with other species and thus, may be less frequent than reported. It is found from the Gulf of St. Lawrence through to Brazil. See general hydroid comments above.

Obelia geniculata
Common Name: Knotted Threadhydroid
This hydroid is also known as a zigzag wineglass hydroid, which is descriptive of its alternating growth pattern. It is common in shallow waters of northeastern North America and found from Newfoundland to Brazil. See general hydroid comments above.

Obelia longissima
Common Name: Bushy Wine-glass Hydroid
This is a whitish, abundantly branched hydroid that can form large bushy colonies. It is very abundant and may grow on floating docks of northeastern North America. It ranges from Subarctic to South Carolina. See general hydroid comments above.

Opercularella lacerata
Common Name: Hydroid
This hydroid may grow on mussels and other attached organisms. It is found from the Arctic Ocean to Long Island Sound and inhabits shallow waters in cold regions. It is more abundant at the northern end of its range than the southern. See general hydroid comments above.

Pennaria disticha
Common Name: Feather Hydroid
This colonial hydroid is brownish, has pink hydranths (anemone-like structures), and is feathery in appearance. It can be common locally, has a strong seasonal component and is found in moderate water currents from Cape Cod to Brazil. See general hydroid comments above.

Polychaeta (Segmented Worms)

Information and descriptions from Marine Polychaete Worms of the New England Region by Marian H. Pettibone, 1963 and A Practical Guide to the Marine Animals of Northeastern North America by Leland Pollack (1997).

Harmothoe imbricata
Common Name: Fifteen-scaled Worm
This scale worm may be found within fouling communities, e.g. in the spaces between mussels and a variety of other surfaces. It is variable in color, with yellow, red and brown, and sometimes with a brown stripe. It may reach sizes of 6.5 cm. It is common, abundant, and found in the intertidal zone at depths down to 275 meters in the Arctic, North Atlantic, and North Pacific from Labrador to New Jersey.

Lepidonotus squamatus
Common Name: Twelve-scaled Worm
This scale worm may reach sizes of 5.0 cm long and 1.5 cm wide. Its coloration is a mottled brown or gray with obvious bumps (tubercles) on its scales. It is one of the most abundant worms and ranges from Labrador and the Gulf of St. Lawrence through to New Jersey and possibly Virginia. It is found at depths of 2500 meters.

Mollusca (Soft-bodied Organisms ñ Snails and Bivalves)

Nudibranchia (Sea slugs)

Cuthona gymnota
Common Name: Sea Slug
Found in the North Atlantic from North and South Europe. Feeds mainly on hydroids. Grows to about 20mm in length but usually smaller. It is similar in appearance to Catriona and Trinchesia but has unpigmented rhinophores.

Tenellia adspersa
Common Name: Miniature Aeolis
This small nudibranch (similar to a garden slug but with tentacles (cerata) on its back) is pale brown with black spots. It has 2-3 rows of cerata and lateral tentacles on its head. It can grow to 7 mm in this region and feeds on a variety of hydroids, especially Cordylophora caspia. It is associated with brackish water and our records show it present in New Hampshire and also from the Chesapeake Bay to Brazil.

Arthropoda

Amphipoda (Amphipods)

Information on amphipods is from Shallow-water Gammaridean Amphipoda of New England by E. L. Bousfield, 1973. For more up-to-date references visit the Amphipod Homepage at http://web.odu.edu/sci/biology/amphome/.

Caprella penantis
Common Name: Skeleton Shrimp
This is one of the most common caprellid amphipods in the region. It can be locally abundant and is found clinging to algae, hydroids and other attached organisms in the subtidal areas.

Stenothoe valida
Common Name: Amphipod
This amphipod is generally considered tropical and is found among hydroids and ectoprocts in subtidal areas.

Tanais dulongii
Common Name: Tanaid Shrimp
No information has been entered on this organism.

Isopoda (Isopod)

Jaera marina
Common Name: Isopod
As a grayish, small, oval isopod it can usually be found in seaweed, mussels, or under stones.

Bryozoa

Information and descriptions in this section are adapted from A Practical Guide to the Marine Animals of Northeastern North America by Leland Pollack (1997) and The Bryozoan home page: http://www.civgeo.rmit.edu.au/bryozoa/default.html. The Bryozoan are undergoing taxonomic reclassification and information on some species was not readily available.

Amathia vidovici
Common Name: Bryozoan
Amathia vidovici is a branching bryozoan arranged in small, twisted clumps of 4 - 8 pairs. Zooids are .04 mm tall. They are typically cream in color.

Bowerbankia gracilis
Common Name: Bryozoan
This creeping bryozoan is a common estuarine species that ranges from Greenland to South America.

Bowerbankia imbricata
Common Name: Bryozoan
This creeping bryozoan is a common estuarine species that ranges from Greenland to South America.

Bugula simplex
Common Name: Fan Bugula
This bryozoan forms thick tufted, yellow-orange colonies on hard surfaces, and is generally found in sheltered locations.

Bugula stolonifera
Common Name: Bryozoan
This organism is found in the northwestern Atlantic. It is a common fouling organism and does not have a whorled, colonial pattern.

Cryptosula pallasiana
Common Name: Orange Crust Bryozoan
This encrusting bryozoan forms circular colonies about 3 cm in diameter and is common in fouling communities. It ranges from Nova Scotia through Florida.

Electra pilosa
Common Name: Bryozoan
This encrusting bryozoan forms grayish, often starlike colonies and is found growing on algae, particularly kelp.

Walkeria uva
Common Name:
No information on this species was currently available.

Tunicata: Ascidiacea (Tunicates)

Information and descriptions are adapted from from Gretchen Lambert, Friday Harbor Laboratories, and A Practical Guide to the Marine Animals of Northeastern North America by Leland Pollack (1997). For more information about tunicates, visit the Ascidian homepage at http://depts.washington.edu/ascidian/.

Ciona intestinalis
Common Name: Sea Vase
This solitary tunicate can reach lengths of 15 cm (6 inches). It is elongated, translucent and usually a pale yellow. It has a bright yellow rim around its siphons as well as eight light-sensitive spots around its oral siphon, and six around its atrial siphon.

Molgula citrina
Common Name:
It is very small, globular, less than half an inch in diameter. Broods its larva. A northern species, common in Canadian maritimes and Maine, rare in Massachusetts.

Molgula provisionalis
Common Name:
This may be the northern European species Molgula macrosiphonica. It has very long siphons with long pointed lobes.

Click here for Introduced Species Descriptions.
Click here to return to the intro page.

Note: The descriptions provided on this page are the most accurate available to us.  We would appreciate any new or updated information, or corrections that you may have.  We welcome your comments and suggestions as we continue to develop this site.