USGS11598.8 Nilssonia serotina Heer GCY84


See also USGS 11598.6

Image of USGS11598.8



Locality Map

Locality USGS 11598, Chignik Area


Fronds: radius stout, straight or slightly curved, rounded on underside, grooved on upper side; lamina dissected into pinnae; pinnae irregularly arranged, broad junction with rachis, parallel or tapering towards obtuse to rounded apex, pinnae margins entire, venation parallel, typically approximately 20 veins per centimeter.


Specimen USGS 11598.8 undoubtedly represents the same species as those specimens figured by Hollick (1930) under the name Nilssonia serotina. All his specimens assigned that name were collected from the Alaska Peninsula. Specimen USGS 11598.6 on the other hand is more like N. yukonensis Hollick from the lower Yukon River localities. N. serotina, however, also encompasses a wide range of morphologies, some of which, in places, lack the pinnatifid dissection of the frond. In the absence of cuticle characters the determination of species within the genus Nilssonia Brogniart is very unreliable.