Achnanthes longboardia
Sherwood and Lowe 2009 Category: Monoraphid
BASIONYM: Achnanthes longboardia Sherwood & Lowe 2009
LM scalebar = 10 µm = 40 pixels.
Observations
Contributor: Rex Lowe - December 2011
Length Range: 22.6-47.8 µm
Width Range: 8-10.5 µm
Striae in 10 µm: 13-15 on raphe valve, 12-14 on rapheless valve
Description
Valves are lanceolate with slightly swollen center and rounded ends. The raphe valve has a narrow axial area with the central area expanded laterally to the valve margins. The proximal raphe ends are deflected slightly in the same direction while the distal raphe ends curve strongly toward the mantle in a direction opposite the proximal raphe ends. The axial area on the rapheless valve is near the valve margin and central area is lacking. On the raphe valve striae are punctate and parallel in the center becoming radiate near the ends. Striae on the rapheless valve are strongly curved near the apicies.
Original Description
Basionym: Achnanthes longboardia
Author: Sherwood & Lowe 2009
Length Range: 19-51 µm
Width Range: 8-11 µm
Striae in 10 µm:
Original Description
Valves lanceolate with rounded ends, slightly swollen near the center in larger valves 19-50.5 long 8-10.5 wide. Raphe valve with narrow axial area with a wide central area expanded laterally to the valve margins. Raphe with proximal ends deflected slightly in the same direction with distal raphe ends curved strongly toward mantle in opposite direction. Rapheless valve with axial area near the valve margin. Striae punctate and parallel in the center becoming radiate near the ends. Striae on the rapheless valve are strongly curved near the apicies.
Original Images
Cite This Page:
Lowe, R. (2011). Achnanthes longboardia. In Diatoms of the United States. Retrieved May 23, 2013, from http://westerndiatoms.colorado.edu/taxa/species/achnanthes_longboardia
Species: Achnanthes longboardia
Contributor: Rex Lowe
Reviewer: Sam Rushforth
Image Credit: Rex Lowe
- Valves lanceolate
- Raphe valve with laterally expanded central area
- Rapheless valve with eccentric axial area
- Ends broadly rounded
Valves lanceolate, slightly swollen near the center, with broadly rounded ends. The raphe valve with a narrow axial area and wide central area, expanded laterally to the valve margins. The proximal raphe ends are slightly deflected in the same direction. The rapheless valve with an axial area positioned near the valve margin.
Compare
Achnanthes longboardia is more lanceolate in shape than A. coarctata, A. mauiensis, A. muelleri and A. inflata. The stria density of A. polynesia is higher.
Achnanthes coarctata
Achnanthes mauiensis
Achnanthes inflata
Achnanthes muelleri
Carlson
Achnanthes polynesia
Lange-Bertalot & Werum
Citations
Lowe, R.L., Sherwood, A.R. and Ress, J.R. (2009). Freshwater species of Achnanthes Bory from Hawai'i. Diatom Research 24(2): 327-340.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID:
Autecology Discussion
Achnanthes longboardia was described from a wet wall in Oahu, Hawaii.