A second species in the siphonous green algal genus Avrainvillea was recently discovered off the island of O‘ahu in the Main Hawaiian Islands. Specimens were collected from Honolulu Harbor, including its entrance channel, and near Ke‘ehi Harbor. These locations are both in Mālama Bay on O‘ahu’s south shore in or adjacent to urbanized estuaries, respectively. In situ observations, morphological and molecular assessments were conducted to examine the alga’s habit and distribution, as well as to assess its putative species identification. The alga occurred in sand as single individuals or in clusters of several individuals at both sites, and near or within seagrass beds ( Halophiladecipiens ) and algal meadows composed of the green alga Halimedakanaloana and an unidentified Udotea species at the Ke‘ehi Harbor site. All analyses supported both populations as representative of the same taxa, reported until further investigation in the broad Pacific as Avrainvilleacf.erecta based on morphological and molecular analyses. This record of a second Avrainvillea species in Hawai'i is of particular concern considering that an alga recognized as A.amadelpha , first observed in 1981 from two locales on O‘ahu’s south shore, has become invasive in Hawai‘i’s intertidal to mesophotic environments.
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Marine Benthic Algae from Ni‘ihau and Adjacent Lehua Islet, Main Hawaiian Islands
The published records of marine benthic algal species from the privately-owned island of
Ni‘ihau (Hawaiian Islands) are represented by four species cited in abbott (1999) and
abbott & Huisman (2004). The species consist of the red alga Chondrophycus dotyi (y.
Saito) k.w. Nam [= Laurencia dotyi y. Saito], two brown algae Dictyopteris plagio -
gramma (Montagne) Vickers and Distromium flabellatum womersley, and the green alga
Pseudochlorodesmis parva w. J. gilbert [= Siphonogramen parvum (w.J. gilbert) I.a.
abbott & Huisman]. Distromium flabellatum and Pseudochlorodesmis parva were collected
in waters between Ni‘ihau and Lehua Islet. The paucity of algal records from
Ni‘ihau is not surprising, very few collections have been made along its coastline because
of its remoteness and general lack of access.
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- Award ID(s):
- 1754117
- NSF-PAR ID:
- 10226451
- Date Published:
- Journal Name:
- Bishop Museum occasional papers
- Volume:
- 129
- ISSN:
- 2376-3191
- Page Range / eLocation ID:
- 93-107
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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