BIOTIC Species Information for Ahnfeltia plicata
|Researched by||Will Rayment||Data supplied by||MarLIN|
|Refereed by||Dr Fabio Rindi|
|Scientific name||Ahnfeltia plicata||Common name||A red seaweed|
|MCS Code||ZM186||Recent Synonyms||None|
|Taxonomy References||Fish & Fish, 1996, Dickinson, 1963, Dixon & Irvine, 1977, Maggs & Pueschel, 1989, Howson & Picton, 1997,|
|Typical food types||Not relevant||Habit||Attached|
|Bioturbator||Not relevant||Flexibility||High (>45 degrees)|
|Height||Growth Rate||See additional information|
|Adult dispersal potential||None||Dependency||Independent|
|General Biology Additional Information||Growth rate
Maggs & Pueschel (1989) recorded observations on growth of Ahnfeltia plicata from Nova Scotia. 4 months after germination of carpospores, tetrasporophyte crusts had grown up to 2.6 mm in diameter. 2 months after germination of tetraspores, the basal holdfast had reached 1.1 mm in diameter, with numerous hair like fronds emerging. After 14 months the axes had grown up to 50 mm in length.
In a continuous spray culture with water at 8-11°C and light intensities of 40-60 µE/m²/s, mean apical growth of Ahnfeltia plicata was 17.2 µm/day over 19 days (Indergaard et al., 1986). Permanently immersed plants under the same conditions grew at approximately 7 µm/day. Conversely, percentage biomass increase was greater under the permanent immersion regime; 0.57% increase in mass/day vs. 0.20% for the plants in spray culture (Indergaard et al., 1986).
|Biology References||Fish & Fish, 1996, Dickinson, 1963, Dixon & Irvine, 1977, Maggs & Pueschel, 1989, Indergaard et al., 1986, Bird et al., 1991,|
|Distribution and Habitat|
|Distribution in Britain & Ireland||Occurs on all coasts of Britain and Ireland. There is a paucity of records from south east England, reflecting a lack of suitable substrata.|
|Global distribution||Occurs in Europe from northern Russia to southern Portugal and in the Baltic Sea. Occurs in the Americas from arctic Canada to Mexico and is widely distributed in the Indian and Pacific Oceans.|
|Biogeographic range||Not researched||Depth range||lower shore to 22 m|
|Migratory||Non-migratory / Resident|
|Distribution Additional Information||Lüning (1990) suggested that Ahnfeltia plicata typically occurs as an understory algae beneath Laminaria sp. at depths of 1.5 to 4 m.|
Coarse clean sand
|Physiographic preferences||Open coast
Strait / sound
Enclosed coast / Embayment
|Biological zone||Lower Eulittoral
|Tidal stream strength/Water flow||Moderately Strong (1-3 kn)
Weak (<1 kn)
|Salinity||Full (30-40 psu)
Variable (18-40 psu)
Reduced (18-30 psu)
|Habitat Preferences Additional Information|
|Distribution References||Fish & Fish, 1996, Dickinson, 1963, Dixon & Irvine, 1977, Maggs & Pueschel, 1989, Lüning, 1990, JNCC, 1999, Picton & Costello, 1998, Lewis, 1964, Connor et al., 1997(a), Hardy & Guiry, 2003,|
See additional information
|Developmental mechanism||Spores (sexual / asexual)
|Reproductive Season||Insufficient information||Reproductive Location|
|Reproductive frequency||Annual protracted||Regeneration potential||No|
|Life span||6-10 years||Age at reproductive maturity||1-2 years|
|Generation time||Insufficient information||Fecundity||No information found|
|Egg/propagule size||Fertilization type|
|Reproduction Preferences Additional Information||Life span
No information was found concerning the longevity of Ahnfeltia plicata. However, it is a slow maturing perennial (Dickinson, 1963) and the thallus survives several years without considerable losses (Lüning, 1990). It likely to have a life span of 5-10 years, similar to other red seaweeds, such as Furcellaria lumbricalis.
Age at maturity
No definitive information was found concerning age at maturity. However, Maggs & Pueschel (1989) made observations of Ahnfeltia plicata from Nova Scotia. Tetrasporophyte crusts matured and released tetraspores after 15 months. Gametangial plants had produced abundant monosporangia after 14 months but no other reproductive structures were formed during this time.
Ahnfeltia plicata has a heteromorphic life history (Maggs & Pueschel, 1989). Carpospores formed on the female thallus as a result of sexual reproduction give rise to the tetrasporophyte encrusting form. In turn, the tetraspores formed on the tetrasporophyte phase give rise to the erect, gametophyte plants. However, male gametophytes also give rise to monosporangia, producing monospores which also develop into gametophytes. Maggs & Pueschel (1989) suggest that the recycling of erect male gametophytes may be important in habitats which are unsuitable for the encrusting phase.
Timing of reproduction
Maggs & Pueschel (1989) recorded observations of reproduction by Ahnfeltia plicata in Nova Scotia. Spermatangia were present on male gametophytes between July and January. Carpogonia were present on female gametophytes between July and November, carposporophytes began development between September and November, and were mature between October and July. Monosporangia, which were only found on male plants in the intertidal, were present from November to January.
|Reproduction References||Dickinson, 1963, Dixon & Irvine, 1977, Maggs & Pueschel, 1989, Lüning, 1990,|