The multicellular bright green thallus of this alga is lamellar, may be whole, dissected or branched. The length of the thallus is, on average, 0.3-1.5 meters. In its structure, two rows of closely adjacent cells are distinguished. At the base of the thallus are large cells with rhizoids that form the sole, through which the algae attaches to the underwater substrate.
Vegetative and sexual methods of reproduction of this alga are possible. Often, a new plant appears from fragments of the body. Young plants can develop from the base of the ulva, more precisely from its sole. During the sexual process, gametes merge from different thalli. The life cycle of the ulva includes two generations - the gametophyte and sporophyte, which look exactly the same and have a similar structure. Sexual reproduction can occur as isogamy or heterogamy.
According to the World Register of Marine Species website, the following species are included in the genus [1] :
- Ulva acanthophora (Kützing) Hayden, Blomster, Maggs, PC Silva, Stanhope & JR Waaland, 2003
- Ulva anandii Amjad & Shameel, 1993
- Ulva arasakii Chihara, 1969
- Ulva atroviridis Levring, 1938
- Ulva beytensis Thivy & Sharma, 1966
- Ulva bifrons Ardré, 1967
- Ulva brevistipita VJ Chapman, 1956
- Ulva burmanica (Zeller) De Toni, 1889
- Ulva californica wille, 1899
- Ulva chaetomorphoides (Børgesen) Hayden, Blomster, Maggs, PC Silva, MJ Stanhope & JR Waaland, 2003
- Ulva clathrata (Roth) C. Agardh, 1811
- Ulva compressa Linnaeus, 1753
- Ulva conglobata Kjellman, 1897
- Ulva cornuta Lightfoot, 1777
- Ulva covelongensis V. Krishnamurthy & H. Joshi, 1969
- Ulva crassa VJ Chapman, 1956
- Ulva crassimembrana (VJ Chapman) Hayden, Blomster, Maggs, PC Silva, MJ Stanhope & JR Waaland, 2003
- Ulva curvata (Kützing) De Toni, 1889
- Ulva denticulata PJL Dangeard, 1959
- Ulva diaphana Hudson, 1778
- Ulva elegans Gayral, 1960
- Ulva enteromorpha Le Jolis, 1863
- Ulva erecta (Lyngbye) Fries
- Ulva expansa (Setchell) Setchell & NL Gardner, 1920
- Ulva fasciata Delile , 1813
- Ulva flexuosa Wulfen, 1803
- Ulva geminoidea VJ Chapman, 1956
- Ulva gigantea (Kützing) Bliding, 1969
- Ulva grandis Saifullah & Nizamuddin, 1977
- Ulva hookeriana (Kützing) Hayden, Blomster, Maggs, PC Silva, MJ Stanhope & JR Waaland
- Ulva hopkirkii (M'Calla ex Harvey) P. Crouan & H. Crouan
- Ulva howensis (AHS Lucas) Kraft, 2007
- Ulva indica Roth, 1806
- Ulva intestinalis Linnaeus, 1753
- Ulva intestinaloides (RPT Koeman & Hoek) Hayden, Blomster, Maggs, PC Silva, MJ Stanhope & JR Waaland, 2003
- Ulva javanica NL Burman, 1768
- Ulva kylinii (Bliding) Hayden, Blomster, Maggs, PC Silva, MJ Stanhope & JR Waaland, 2003
- Ulva lactuca Linnaeus, 1753
- Ulva laetevirens JE Areschoug, 1854
- Ulva laingii VJ Chapman, 1956
- Ulva linearis PJL Dangeard, 1957
- Ulva linza Linnaeus, 1753
- Ulva lippii Lamouroux
- Ulva litoralis Suhr ex Kützing
- Ulva littorea suhr
- Ulva lobata (Kützing) Harvey, 1855
- Ulva marginata (J. Agardh) Le Jolis
- Ulva micrococca (Kützing) Gobi
- Ulva neapolitana Bliding, 1960
- Ulva nematoidea Bory de Saint-Vincent, 1828
- Ulva ohnoi Hiraoka & Shimada, 2004
- Ulva olivascens PJL Dangeard
- Ulva pacifica Endlicher
- Ulva papenfussii Pham-Hoang Hô, 1969
- Ulva parva VJ Chapman, 1956
- Ulva patengensis Salam & Khan, 1981
- Ulva percursa (C. Agardh) C. Agardh
- Ulva pertusa Kjellman, 1897
- Ulva phyllosa (VJ Chapman) Papenfuss
- Ulva polyclada Kraft, 2007
- Ulva popenguinensis PJL Dangeard, 1958
- Ulva porrifolia (SG Gmelin) JF Gmelin
- Ulva profunda WR Taylor, 1928
- Ulva prolifera OFMüller, 1778
- Ulva pseudocurvata Koeman & Hoek, 1981
- Ulva pseudolinza (RPT Koeman & Hoek) Hayden, Blomster, Maggs, PC Silva, MJ Stanhope & JR Waaland, 2003
- Ulva pulchra Jaasund, 1976
- Ulva quilonensis Sindhu & Panikkar, 1995
- Ulva radiata (J. Agardh) Hayden, Blomster, Maggs, PC Silva, MJ Stanhope & JR Waaland, 2003
- Ulva ralfsii (Harvey) Le Jolis, 1863
- Ulva ranunculata Kraft & AJK Millar, 2000
- Ulva reticulata Forsskål, 1775
- Ulva rhacodes (Holmes) Papenfuss, 1960
- Ulva rigida C. Agardh, 1823
- Ulva rotundata Bliding, 1968
- Ulva saifullahii Amjad & Shameel, 1993
- Ulva serrata APde Candolle
- Ulva simplex (KL Vinogradova) Hayden, Blomster, Maggs, PC Silva, MJ Stanhope & JR Waaland, 2003
- Ulva sorensenii VJ Chapman, 1956
- Ulva spinulosa Okamura & Segawa, 1936
- Ulva stenophylla Setchell & NL Gardner, 1920
- Ulva sublittoralis Segawa, 1938
- Ulva subulata (Wulfen) Naccari
- Ulva taeniata (Setchell) Setchell & NL Gardner, 1920
- Ulva tanneri HS Hayden & JR Waaland, 2003
- Ulva tenera Kornmann & Sahling
- Ulva torta (Mertens) Trevisan, 1841
- Ulva tuberosa Palisot de Beauvois
- Ulva uncialis (Kützing) Montagne, 1850
- Ulva uncinata Mohr
- Ulva uncinata Mertens
- Ulva usneoides Bonnemaison
- Ulva utricularis (Roth) C. Agardh
- Ulva utriculosa C. Agardh
- Ulva uvoides Bory de Saint-Vincent
- Ulva ventricosa APde Candolle
