Favoritos de chlorophilia

Thalassiosira pacifica Gran & Angst, 1931

Phylum: Bacillariophycophyta, Subphylum: Bacillariophytina, Class: Mediophyceae, Order: Thalassiosirales, Family: Thalassiosiraceae.

SEM images of the marine diatom Thalassiosira pacifica Gran & Angst, 1931.

Girdle view: Cells 16.1-28.8 µm (7.0–55.0) µm in diameter. GI = n = 3.
Cells rectangular with rounded low mantle. Valve face flat or slightly concave. Connecting thread about as long as the pervalvar axis.
Valve view:
Loculate areolae in linear (straight), eccentric or fasciculate patterns (curved) rows depending on the diameter of the cell. Central process (A.) adjacent to a central areola (annulus) (B.). Valve face areolae (C.) 10-19 in µm (Hasle and Syvertsen 1996, Li et al. 2014). GI = 14-16 in 10 µm. 20 to 28 areolae in 10 µm (Hoppenrath et al. 2007, not so). Valve face covered by tiny siliceous granules (D.) (Hoppenrath et al. 2007). Marginal strutted processes (MSPs) with relatively long and coarse external tubes. GI specimens have a bulbous and coarse flared tip. MSPs 4-7 in 10 µm. GI = 4-6 in 10 µm. Separation between MSPs = 1-2 µm (GI) Mantle areolae smaller than those on valve face. The height of mantle is about 2–3 areolae (Li et al. 2014). Labiate process positioned as for a marginal strutted process, slightly inside the marginal ring. Labiate process slightly larger than the marginal strutted processes.Valve margin ribbed.
Notes: Mantle areolae smaller than those on valve face. Valve margin ribbed. Distinguished from T. angulata by the ribbed margin and the more closely spaced marginal processes with shorter
external tubes and the location of the labiate process. (Hasle and Syvertsen 1996:37; Mahood et al. 1986; Hoppenrath et al. 2007; Li et al. 2013. (Hoppenrath et al. 2007 –Fig. 45-46, scale bar = 10 µm)

Methods:

A distal section of the eelgrass Zostera marina was heated and digested in 95-99C sulfuric acid, rinsed in distilled water and further cleaned or organics with 30% hydrogen peroxide and with further rinsing, brought to a pH of 6.5. Pipetted and syringed with further washes of sterile distilled and deionized water using a Swinnex filter holder onto 12 mm Teflon 0.2 µm filters and attached to 13 mm SEM stub with double sided tape. Imaging with a Hitachi s4800 SEM at the AMF at UVIC. Thank you Ron Read for taking the SEM images and Elaine Humphrey for SEM support at University of Victoria, BC, Canada. Adjusted in Photoshop.

References:

Cupp, E. E. 1943. Marine Plankton Diatoms of the West Coast of North America. University of California Press. Berkeley, California.

Gran, H.H. and Angst, E.C. (1931). Planktonic Diatoms of Puget Sound. Seattle, University Press. https://babel.hathitrust.org/cgi/pt?id=uc1.31822010334225&view=1up&seq=3

Hoppenrath, M., Beszteri, B., Drebes, G., Halliger, H., Van Beusekom, J.E.E. , Janisch, S. and Wiltshire, K. H. (2007) Thalassiosira species (Bacillariophyceae, Thalassiosirales) in the North Sea at Helgoland (German Bight) and Sylt (North Frisian Wadden Sea) – a first approach to assessing diversity, European Journal of Phycology, 42:3, 271-288, DOI: 10.1080/09670260701352288

Horner, R.A., Postel, J.R., Halsband-Lenk, C., Pierson, J.J., Pohnert, G. and Wichard, T. 2005.Winter-spring phytoplankton blooms in Dabob Bay, Washington. Prog. Oceanogr. 67 (3-4): 286-313.

Hasle, G.R. & Syvertsen, E.E. (1996). Marine Diatoms. In: Identifying Marine Phytoplankton. (Tomas, C.R. Eds). San Diego: Academic Press.

Guiry, M.D. & Guiry, G.M. 2007, AlgaeBase version 4.2. World-wide electronic publication, National University of Ireland, http://algaebase.org, searched April 10, 2022.

Li, Y. and Lu, S. (2013). The genus Thalassiosira off the Guangdong coast, South China Sea. Botanica Marina; 56(1): 83–110. DOI: 10.1515/bot-2011-0045

Mahood, A.D., Fryxell, G.A., & Mcmillan, M. (1986). The diatom genus Thalassiosira: species from the San Francisco Bay system. Proc. Calif. Acad. Sci. 24: 127–156.

Round, F.E., Crawford, R.M. and Mann, D.G. (1990). The Diatoms, Biology & Morphology of the Genera. Cambridge University Press, Cambridge, UK. pp. 132-133.

Hay, M. B., Pienitz, R., and Thomson, R.E. (2003). Distribution of diatom surface sediment assemblages within Effingham Inlet, a temperate fjord on the west coast of Vancouver Island (Canada). , 48(3-4), 291–320. doi:10.1016/s0377-8398(03)00025-2

Sancetta, C. and Calvert S. E. (1988). The annual cycle of sedimentation in Saanich Inlet, British Columbia:implications for the interpretation of diatom fossil assemblages. Deep-Sea Research, Vol. 35, No. 1, pp. 71-90.

Shim, J. H. (1976). Distribution and Taxonomy of Planktonic Marine Diatoms in the Strait of Georgia, B.C. Phd. Thesis, UBC.

Waters, R. E., Brown, L.N., and MG Robinson, M.G. (1992). Phytoplankton of Esquimalt Lagoon, British Columbia: comparison with west Vancouver Island coastal and offshore waters. Canadian Technical Report of Hydrography Ocean Sciences 137.

Maybe a Trentepohlia? It seemed very coarse - stiff compared to other more hairlike Trentepohlia(s) found in the area. Found during dry weather on rocks in muskeg at around 1,000 ft elevation. It was peeling off the rock with a skin like membrane where it contacted the rock.

Another interesting, seemingly contradictory to the Trentepohlia idea, is the fact that this is growing on the SSE face of an exposed boulder which would experience considerable sunny drying conditions. The Trentepohlias in this area usually seem restricted to dark shady north facing habitats it seems?

Pretty extensive, usually pure fruiting patches or with other ruderal bryos. Mature bright red tubers are 160-200um, but many were presumably immature and around 100-130um. Smooth, sometimes reddish rhizoids.

These little critters were erupting (hatching?) from what looked to
be a single opening in an oyster mushroom. There was a single adult (mom?) who appeared to be assisting them - at times being in the very thick of the eruption. Any ideas welcome!