Gomphonema johnsonii Bahls, 2013
publication ID |
https://doi.org/ 10.11646/phytotaxa.82.1.2 |
persistent identifier |
https://treatment.plazi.org/id/03F2878E-FFC5-F86E-46F6-FAB46387FF01 |
treatment provided by |
Felipe |
scientific name |
Gomphonema johnsonii Bahls |
status |
sp. nov. |
Gomphonema johnsonii Bahls , sp. nov. ( Figs 34–42 View FIGURES 34–42 )
Valves lanceolate with narrow subrostrate apices. Valve length 24–50 µm; valve width 6.9–8.5 µm. Pore field present at the footpole. Valves somewhat asymmetric about the apical axis. Axial area narrow and linear, widening to merge with a moderately large elliptic central area. Raphe straight and weakly lateral, becoming filiform at the proximal and distal ends. Proximal raphe ends weakly expanded; terminal raphe fissures hooked to the side opposite the central stigma. Striae strongly radiate, 9–12 in 10 µm at the valve center, 14–18 in 10 µm near the apices. Areolae 30–35 in 10 µm. One stigma present at the end of the longest central stria.
Holotype: — USA, Oregon: Lane County, Spring along Forest Road No. 1900482, 44.1342 o N, 122.2286 o W, elev. 604 m, coll. A. Johnson, 10 August 2011. MDC sample 500301; holotype slide MDC 42-2 ( Figs 34–42 View FIGURES 34–42 ) (circled holotype specimen in Fig. 38 View FIGURES 34–42 ). MONTU! GoogleMaps
Isotypes: —MDC slide 126-96 ( MONTU!); circled specimens on ANSP! GC 65164.
Etymology:—This taxon is named for Al Johnson, hydrologist with the Willamette National Forest and collector of the type sample.
Observations:—Under SEM, a well-developed apical pore field at the footpole and C-shaped external openings of the areolae are evident ( Fig. 42 View FIGURES 34–42 ). Gomphonema parvulum (Kützing) Kützing (1849: 65) is smaller (10–36 µ m long) with less strongly radiate striae. Gomphonema gracile Ehrenberg (1838: 217) lacks protracted apices and also has more weakly radiate striae. Valves of Gomphonema mexicanum Grunow in Van Heurck (1880: pl. 24, fig. 3) are larger and lack the protracted headpole.
Distribution: — Gomphonema johnsonii is known to date only from the type locality.
Order Naviculales Bessey 1907: 10
Family Cavinulaceae D.G. Mann in Round et al. 1990: 659
Genus Cavinula D.G. Mann & A.J. Stickle in Round et al. 1990: 665
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
Kingdom |
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Phylum |
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Class |
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Order |
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Family |
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Genus |
Gomphonema johnsonii Bahls
Bahls, Loren 2013 |
Cavinulaceae D.G. Mann
Round, F. E. & Crawford, R. M. & Mann, D. G. 1990: 659 |
Cavinula D.G. Mann & A.J. Stickle
Round, F. E. & Crawford, R. M. & Mann, D. G. 1990: 665 |
Naviculales
Bessey, C. 1907: 10 |