NEMESIS Bioregion Distribution:

Native  Introduced  Cryptogenic  Failed

First Non-native North American Marine/Estuarine Record: 1988
First Non-native East/Gulf Coast Marine/Estuarine Record: 1988

General Invasion History:

Didemnum psammatodes was first described in Northern Australia. It is native to the tropical and subtropical regions of the Indo-West Pacific (Monniot and Monniot 1985; Monniot and Monniot 1994; Carlton and Eldredge 2009; Gretchen Lambert, personal communication 2005). The presumed native range extends from East Africa to China, Japan, Fiji, Tonga, and New Zealand. Lambert (2002) considers it cryptogenic in Guam and it is considered introduced to the Hawaiian Islands and the Pacific entrance of the Panama Canal (Calton and Eldredge 2009; Carman et al. 2010).

Didemnum psammatodes is introduced to the Atlantic and was probably overlooked for decades before being reported in Guadeloupe in 1980-1981 (Monniot and Monniot 1985). In the 1980s it was reported from the Indian River Lagoon, Florida and Sao Sebastiao, Brazil (Bingham 1992; da Rocha and Monniot 1995) and in 1990 it was collected from Sierra Leone, West Africa (Monniot and Monniot 1994). It was probably transported to the Atlantic through ship fouling (Farrapeira et al. 2007).

North American Invasion History:

Invasion History on the East Coast:

Didemnum psammatodes was reported from the Indian River Lagoon, Fort Pierce, Florida in 1988, where it is abundant on mangrove roots and in seagrass beds (Bingham 1992; Ruiz et al., unpublished data). It occurs in Biscayne Bay (reported in 2004, Ruiz et al., unpublished data) and north to St. Augustine in Florida (Smithsonian Marine Station at Fort Pierce 2011). 

Invasion History on the Gulf Coast:

On the Gulf Coast, Didemnum psammatodes was collected in a marina at Port Isabel, Texas in 2004 (Lambert et al. 2005), but was not identified on settling plates in other Gulf Coast ports in 2000-2003 (Ruiz et al., unpublished data).

Invasion History in Hawaii:

Didemnum psammatodes has been introduced to Hawaii, where it was first collected in Oahu in 1998. It has since been found in several harbors and marinas on the island (Carlton and Eldredge 2009).

Invasion History elsewhere in the World:

Didemnum psammatodes has been collected in Panama Bay, near the entrance to the Pacific side of the Panama Canal (Carman et al. 2010).

In the Atlantic, it was first reported from Guadeloupe (in 1980-81, Monniot and Monniot 1983) and subsequently found in Sao Sebastio, Brazil (in 1985, da Rocha and Monniot 1995), northeastern Brazil (in 2001, Gama et al. 2006), French Guiana (Monniot and Monniot 1994), Bocas del Toro, Panama (da Rocha et al. 2005), Colon, Panama (in 2004, Ruiz et al., unpublished data), Belize (in 1985, Goodbody 2000), and Jamaica (Goodbody and Webber 2003). In the Eastern Atlantic it was collected in Freetown, Sierra Leone, West Africa (Monniot and Monniot 1994).