Name: Corbicula fluminea/ Asian clam Phylum: Molluska, Class: Bivalvia

Presentation on theme: "Name: Corbicula fluminea/ Asian clam Phylum: Molluska, Class: Bivalvia"— Presentation transcript:

1 Name: Corbicula fluminea/ Asian clam Phylum: Molluska, Class: Bivalvia
Photo: Betsy Wells Name: Corbicula fluminea/ Asian clam Phylum: Molluska, Class: Bivalvia Origin: Non-native, from East Asia in 1945 (widespread by 1948) Habitat: freshwater but tolerates salinity up to 17 ppt; fine or coarse clean sand or clay Size: up to ~ 40 mm shell length Notes: Filter feeder which can settle in water intake pipes and clog them.

2 Name: Potamocorbula amurensis/ Asian overbite clam or Asian river clam
Phylum: Molluska, Class: Bivalvia Origin: Non-native, from East Asia in 1986, probably in ballast water Habitat: tolerates salinity from almost freshwater (1ppt) and to full marine levels (35 ppt) but in San Francisco Estuary thrives in Suisun and Grizzly Bay at salinity levels around 3-10 ppt; subtidal in muddy or sandy sediment Size: up to ~25 mm shell length Notes: A prolific filter feeder which has significantly reduced phytoplankton in the estuary, contributing to the decline of several zooplankton and fish species.

3 Name: Theora lubrica / Asian semele, window shell
1 cm Photo: Betsy Wells Name: Theora lubrica / Asian semele, window shell Phylum: Molluska, Class: Bivalvia Origin: Non-native, from Sea of Japan in 1982, probably in ballast water Habitat: higher salinities, from ppt, in subtidal muddy sediment Size: up to 16 mm shell length Notes: Considered a pollution indicator because of its tolerance for low oxygen levels and organic-rich sediment. Deposit feeder that consumes benthic detritus and diatoms

4 Photo courtesy of Global Invasions Research Coordination Network
Name: Melanoides tuberculata/ Red-rim melania or Malaysian trumpet snail Phylum: Molluska, Class: Gastropoda Origin: Non-native, originally found from Northern Africa to Southern Asia; introduced by the aquarium industry to the Delta in 1988 Habitat: freshwater, in sand, mud, and organic detritus Size: up to mm, but usually only 4-5 mm in the Delta Notes: Grazes on microalgae and detritus and serves as food in turn to crabs, fishes, and birds, passing on the many trematode worms that parasitize it to its own predators.

5 Name: Ampelisca abdita
Phylum: Arthropoda, Class: Amphipoda Origin: Non-native from East Coast of North America, first observed in San Francisco Estuary in 1954; probably introduced with Eastern oysters transplanted for aquaculture Habitat: higher salinities of San Pablo and San Franciso Bay; lives in a tube it constructs out of the mud or silt Size: usually 7-8 mm Notes: Consumes plankton but is also an opportunistic scavenger, predator, and even cannibal.

6 Name: Gammarus daiberi
Phylum: Arthropoda, Class: Amphipoda Origin: Non-native from East Asia, introduced in 1986 Habitat: muddy sand bottoms from the low salinity zone (1-6 ppt) of Suisun Bay up into freshwater Size: up to 8 mm Notes: Grazes on phytoplankton; is a common fish food item; reaches sharp seasonal peaks of density in spring and summer.

7 Name: Corophium alienense
Phylum: Arthropoda, Class: Amphipoda Origin: Likely native to the Pacific Northwest Habitat: Lives in mud tubes, in brackish water between 5-10 ppt Size: ??? Notes: Active filter feeder on plankton, and eaten by various fish

8 Phylum: Annelida, Class: Polychaeta
1 cm Photo: Betsy Wells Name: Laonome calida Phylum: Annelida, Class: Polychaeta Origin: Non-native from Australia, first described in the Delta in 1998 Habitat: Lives in a tube made of mucus and fine sediment particles, common in water 5-10 ppt but tolerates a wide range of salinity. Size: 9-15 mm long Notes: L. calida is a sabellid worm, with a crown of feathery tentacles (cirri) that obtain oxygen from the surrounding water and aid in feeding on suspended food particles

9 Name: Limnodrilus hoffmeisteri Phylum: Annelida, Class: Oligochaeta
Photo: Betsy Wells Name: Limnodrilus hoffmeisteri Phylum: Annelida, Class: Oligochaeta Origin: Non-native but origin unknown; found worldwide Habitat: Freshwater, living in a variety of sediments Size: cm or larger Notes: Deposit feeders that are tolerant of polluted sediments, especially heavy metals.

10 Name: Phoronopsis harmeri Phylum: Phoronida/ horseshoe worm.
Photo courtesy of Theresa Zubi Name: Phoronopsis harmeri Phylum: Phoronida/ horseshoe worm. Origin: Native Habitat: Marine (water 25 ppt or higher), living in tubes they construct Size: 20-? mm long Notes: Filter-feeders with a U-shaped crown of tentacles called a lophophore; can reach high densities in San Pablo Bay in the fall and early winter of dry years, but do not tolerate influxes of fresh water.