| Macrostomum bicurvistyla Armonies & Hellwig, 1987 | Jul 25, 1988 | | coarse sand, gravel, boulders | Lower beach slope with effluent freshwater. |
| Coelogynopora sewardensis Ax & Armonies, 1990 | Jul 20, 1988 | | coarse sand, gravel | Lower beach slope with coarse sand and gravel. |
| Coelogynopora sewardensis Ax & Armonies, 1990 | Jul 25, 1988 | | coarse sand, gravel | Lower beach slope with coarse sand and gravel. |
| Archotoplana macrostylis Ax & Armonies, 1990 | Jul 8, 1988 | | coarse sand, gravel, boulders | numerous. |
| Archotoplana macrostylis Ax & Armonies, 1990 | Jul 20, 1988 | | coarse sand, gravel, boulders | lower part of the beach with effluent freshwater, abundant. |
| Archotoplana macrostylis Ax & Armonies, 1990 | Jul 25, 1988 | | coarse sand, gravel, boulders | lower part of the beach with effluent freshwater, abundant. |
| Archotoplana macrostylis Ax & Armonies, 1990 | Aug 13, 1988 | | coarse sand, gravel, boulders | lower part of the beach with effluent freshwater, abundant. |
| Haloplanella obtusituba Luther, 1946 | Jul 8, 1988 | | mud, sand | Fourth of July Beach, muddy sand of the upper intertidal zone. |
| Haloplanella obtusituba Luther, 1946 | Aug 13, 1988 | | mud, sand | Fourth of July Beach, muddy sand of the upper intertidal zone. |
| Haloplanella obtusituba Luther, 1946 | Jul 20, 1988 | | fine-medium sand | Fourth of July Beach, medium to fine intertidal sand. |
| Ptychopera alaskana Ax & Armonies, 1990 | Jul 11, 1988 | | mud | Fourth of July Beach. |
| Ptychopera alaskana Ax & Armonies, 1990 | Aug 13, 1988 | | mud | Fourth of July Beach. |
| Ptychopera alaskana Ax & Armonies, 1990 | Jul 20, 1988 | | fine-medium sand | Fourth of July Beach. |
| Duplacrorhynchus major Schockaert & Karling, 1970 | Jul 8, 1988 | | mud, sand | upper intertidal muddy sand. |
| Duplacrorhynchus major Schockaert & Karling, 1970 | Aug 13, 1988 | | mud, sand | upper intertidal muddy sand. |
| Duplacrorhynchus major Schockaert & Karling, 1970 | Jul 20, 1988 | | fine-medium sand | intertidal. |
| Placorhynchus pacificus Karling, 1989 | Jul 11, 1988 | | muddy sand | |
| Baicalellia pusilla (Luther, 1962) | Jul 8, 1988 | | mud | mud from the border of the salt marsh, (occurring regular). |
| Baicalellia pusilla (Luther, 1962) | Jul 11, 1988 | | muddy sand | regular in low abundance. |
| Baicalellia pusilla (Luther, 1962) | Aug 13, 1988 | | muddy sand | regular in low abundance. |
| Baicalellia pusilla (Luther, 1962) | Jul 20, 1988 | | fine-medium sand | fine to medium intertidal sand. |
| Pogaina alaskana Ax & Armonies, 1990 | Jul 8, 1988 | | muddy sand | Muddy sand of the upper intertidal. |
| Pogaina alaskana Ax & Armonies, 1990 | Jul 11, 1988 | | muddy sand | Muddy sand of the upper intertidal. |
| Baicalellia sewardensis Ax & Armonies, 1990 | Jul 8, 1988 | | muddy sand | Fourth of July Beach. Muddy sand of the upper intertidal. |
| Baicalellia sewardensis Ax & Armonies, 1990 | Jul 11, 1988 | | muddy sand | Fourth of July Beach. Muddy sand of the upper intertidal. |
| Baicalellia sewardensis Ax & Armonies, 1990 | Aug 13, 1988 | | muddy sand | Fourth of July Beach. Muddy sand of the upper intertidal. |
| Baicalellia sewardensis Ax & Armonies, 1990 | July 20, 1988 | | fine-medium sand | Fourth of July Beach. medium to fine intertidal sand, abundant. |
| Halammovortex nigrifrons (Karling, 1935) | July 20, 1988 | | fine-medium sand | Fourth of July Beach. medium to fine intertidal sand. |
| Halammovortex nigrifrons (Karling, 1935) | Jul 8, 1988 | | muddy sand | Fourth of July Beach. muddy sand of the upper intertidal. |
| Halammovortex promacropharynx Ax, 2008 | 1990 or ealier | | | Seward, Alaska, Fourth of July Beach; Lowell Point. |