Paleobiota of the Latah Formation

The paleobiota of the Latah Formation encompasses both floral and faunal elements preserved in temporary lacustrine environments formed between eruptive phases of the Columbia River Basalts in central to east Eastern Washington and central to north Idaho. The Latah Formation is centered around the greater Spokane area, with a western extent outcropping at Grand Coulee and the eastern margins as far southeast as the area of White Bird, Idaho.^[1] Dating of the core Spokane sites is based on the host Grande Ronde Basalts which give an age range of 16.5 to 16.1 million years ago. The Clarkia fossil beds lagerstätte site are slightly younger, being interbedded in the Wanapum Basalts Priest Rapids Member with an age constraint of 16.1 to 15.9 million years ago,^[2] or Early Barstovian in age.^[3]

Spokane Falls, Spokane

Grand Coulee Dam & Electric City

The intermittent lakes were surrounded by a temperate ecosystem that was mesophytic in nature, and hosting a diverse flora with plants that are still native to the region and others now restricted to other areas of the globe. There is a small element of the flora that consists of fully extinct genera that are unique to the time and region.^[2] Based on work from sampling around Mica, Washington a diverse assembly of diatoms and algae lived in the Spokane area lakes though water conditions for growth were not ideal.^[4] The known fauna of the formation is smaller than the flora, with most taxa being insect species^[5] though one unnamed Sciuridae fossil was described in 2018,^[3] and fish belonging to the salmonid, cyprinid, and centrarchid groups are known.^[6] Preservation varies from carbonized compressions at most sites to exceptional organic preservations in some parts of the Clarkia area localities where original organic material is preserved down to living coloration and possible ancient DNA fragments.^[7] Upper layers of the Clarkia deposits have been recorded with modern fungi actively feeding on the ancient organic material of the fossils as a food source.^[7]

Plants

The initial taxonomic work on the flora was undertaken by Frank Knowlton with assistance from diatom specialist Albert Mann and bryologist Elizabeth Britton.^[8] Their combined work was published as a supplemental chapter to the initial 1926 descriptive work by Joseph Pardee and Kirk Bryan. After Knowlton's death in November 1926, his revision of the Latah flora was taken over by Edward W. Berry who also erroneously included strata of the much older Klondike Mountain Formation around Republic, Washington.^[9] This error was noted and corrected in later works by Roland W. Brown.^[10] Ralph W. Cheney and Daniel I. Axelrod broke the Latah into four major florules, Grand Coulee and Spokane in Washington plus Coeur d'Alene and White Bird in Idaho, while noting several "miscellaneous" sites as well.^[1] Modern works have concentrated more on single taxa and certain florules.^[2]

Mosses

Family	Genus	Species	Author/year	Florule	Notes	Synonyms	Images
Polytrichaceae	†Polytrichites	†Polytrichites spokanensis[8]	Britton	Spokane	A possible polytrichaceous moss		Polytrichites spokanensis
incertae sedis	†Hypnites	†Hypnites brittoniae	(Steere) Miller[11]	Spokane	A moss of uncertain affiliation.	Archaeomnium brittoniae (1952)[12] "Moss, genus and species (?)" of Knowlton, 1926 Paleohypnum brittoniae (1946)	Hypnites brittoniae
		†Hypnites patens[12]	(Britton) Miller	Spokane	A moss of uncertain affiliation	Archaeomnium patens (1926)[8]	Hypnites patens

Lycopods

Family	Genus	Species	Author/year	Florule	Notes	Images
Lycopodiaceae	Lycopodium	†Lycopodium hesperium[8]	Knowlton	Coeur d'Alene	A possible lycopod clubmoss Treated as a plant of uncertain affinity by Chaney & Axelrod 1959[1]	Lycopodium hesperium

Ferns

Family	Genus	Species	Author/year	Florule	Notes	Synonyms	Images
Blechnaceae	Woodwardia	†Woodwardia praeradicans	Berry	Spokane	A chain fern species		Woodwardia praeradicans
Equisetaceae	Equisetum	†Equisetum alexanderi[10]	Brown	Spokane	A horsetail species
Dennstaedtiaceae	Pteridium	†Pteridium calabazensis[13]	(Dorf) Graham	Misc - Alkali Creek	A Pteridium fern species	Dryopteris idahoensis (of Berry, 1934)[14] Pteris idahoensis (1959)[1]
Osmundaceae	Osmunda	†Osmunda occidentalis[10]	(Berry) Brown	Spokane	A royal fern species Not to be confused with Asplenium occidentale Knowlton (1917)	Asplenium occidentale Berry (1929) Pteris sp. Berry (1929) "Fern, fragment" of Knowlton, 1926[8]	Osmunda occidentale
Woodsiaceae	Woodsia	†Woodsia bonseri	Berry	Spokane	A cliff fern species		Woodsia bonseri

Ginkgos

Family	Genus	Species	Author/year	Florule	Notes	Images
Ginkgoaceae	Ginkgo	†Ginkgo adiantoides[8]	(Unger) Heer	Clarkia Grand Coulee Spokane	A ginkgo species	Ginkgo adiantoides

Conifers

Family	Genus	Species	Author	Florule	Notes	Synonyms	Images
Cupressaceae	Juniperus	†Juniperus sabinoides	Ashlee	White Bird[15]	A juniper species
	Metasequoia	†Metasequoia occidentalis		Clarkia[16]	A dawn redwood species.
	Taxodium	†Taxodium dubium	(Sternberg) Heer	Clarkia[16] Coeur d'Alene Grand Coulee Spokane[8] White Bird Misc locals	A bald-cypress.	Glyptotrobus aments of Berry, 1929[17] Sequoia langsdorfii of Knowlton, 1926[17] Sequoia langsdorfii of Berry, 1929[17] Sequoia langsdorfii of Berry, 1931[17]	Taxodium dubium
	Tetraclinis	†Tetraclinis salicornioides var. praedecurrens[18]	(Knowlton) Kvaček & Manchester	Clarkia[16] Grand Coulee[14] Misc-Potlatch (Julietta) Spokane[14] White Bird[14]	A Tetraclinis species.	Callitris potlatchensis (1935) Fokienia praedecurrens (1959) Fokieniopsis praedecurrens (1997).[19] Libocedrus praedecurrens (1926)[8] Tetraclinis potlachensis (1997)	Tetraclinis salicornioides var. praedecurrens
	Thuja	†Thuja dimorpha	(Oliver) Chaney & Axelrod	Spokane[1]
Pinaceae	Keteleeria	†Keteleeria heterophylloides	(Berry) Brown	Spokane[9] Misc-Clearwater River[14]	A Keteleeria species.	Potamogeton heterophylloides (1929)[20]	Keteleeria heterophylloides
	Pinus	†Pinus harneyana	Chaney & Axelrod 1959[1]	Spokane	A pine		Pinus harneyana
		†Pinus wheeleri	Cockerell	Spokane[9] White Bird[14]	A pine	Pinus monticolensis p.p.(not Republic specimens)
	Tsuga	†"Tsuga latahensis"	Berry	Grand Coulee Spokane	First described as a hemlock conescale.[21] Suggested to be a bud scale in 1937.[10] Treated as an incertae sedis plant by Chaney & Axelrod (1959).[1]		Tsuga latahensis
Taxaceae	Cephalotaxus	†Cephalotaxus bonseri[1]	(Knowlton) Cheney & Axelrod	Spokane	A yew	Torreya bonseri (1926)[8] Tumion bonseri (1952)	Cephalotaxus bonseri

Basal dicots

Family	Genus	Species	Author	Florule	Notes	Images
Nymphaeaceae	Nymphaea	Unidentified.[22]		Clarkia	A Nymphaea species leaf Not describable to species

Monocots

Family	Genus	Species	Author	Florule	Notes	Synonyms	Images
Araceae	Arisaema	†Arisaema hesperia[8]	Knowlton	Coeur d'Alene	An Arisaema species. Has been suggested as a synonym of Liquidambar pachyphyllum[12]		Arisaema hesperia
	Lysichiton	†"Lysichiton washingtonense"[21]	Berry	Grand Coulee	First described as a skunk cabbage.[21] Later treated as a species of uncertain affinity.[1]		Lysichiton washingtonense
Smilacaceae	Smilax	†Smilax magna	Chaney	Spokane[9] White Bird[15][14]	A green briar species	Aristolochia White Birdensis Ashlee (1932) Smilax lamarensis non Knowlton nec Berry (1929)	Smilax magna
		†Smilax praelaurifolia[15]	Ashlee	Misc	A green briar species
Typhaceae	Typha	†Typha lesquereuxi	Cockerell	Spokane[14] Misc - Arrow Junct.[14]	A cattail species	Typha sp. of Knowlton, 1926[14]	Typha lesquereuxi
Unidentified	Unidentified	Unidentified		Spokane	A poaceous like leaf. Knowlton did not consider Latah Formation leaves as name-able.		unnamed "Grass" leaf
		Unidentified		Spokane	Possibly a poalean plant Suggested to be a low-growing "grass"		Grass?, genus? of Knowlton 1926

Magnoliids

Family	Genus	Species	Author	Florule	Notes	Synonyms	Images
Lauraceae	Machilus	†Machilus americana[10]	Brown	Spokane	A Machilus species
		†Machilus asiminoides[10]	Brown	Spokane	A Machilus species
	Persea	†Persea lanceolata[23]	(Berry) Brown	Grand Coulee Misc-Clearwater River[14] Misc-Juliaetta[14] Spokane White Bird[14]	An avocado species	Laurus similis (non-typic)[23] Umbellularia lanceolata (1929)[14][23]	Persea lanceolata
	Umbellularia	Umbellularia saliciformis[12]	(Knowlton & Cockerell) LaMotte	Grand Coulee Spokane	A pepperwood species.	Laurus similis non Knowlton nec Berry, (1929) Leguminosites bonseri Berry, 1929 (1929) Quercus simulata non Knowlton nec Berry, (1929) Umbellularia dayana non Knowlton nec Brown (1937)	Umbellularia saliciformis
Magnoliaceae	Liriodendron	†Liriodendron hesperia[24]	Berry	Clarkia Spokane White Bird	A tulip tree species		Liriodendron hesperia
	Magnolia	†Magnolia dayana	Cockerell	Grand Coulee[21] Misc-Juliaetta[14] Misc-St Maries[14] Spokane[8][9] White Bird[14]	A magnolia species	Hicoria washingtoniana (1931)[23] Laurus grandis of Knowlton, 1926 Laurus grandis of Berry, 1929 Laurus grandis of Berry, 1934 Laurus princeps of Knowlton, 1926	Magnolia dayana
		†Magnolia latahensis[10]	(Berry) Brown	Spokane	A magnolia species	Apocynophyllum latahense (1929) Magnolia californica of Berry, 1929	Magnolia latahensis

Ceratophyllales

Family	Genus	Species	Author	Florule	Notes	Images
Ceratophyllaceae	Ceratophyllum	†"Ceratophyllum praedemersum"	Ashlee	Spokane	First described as a Ceratophyllum Reidentified as a possible immature platanaceous fruiting axis.[25]

Basal eudicots

Family	Genus	Species	Author	Florule	Notes	Synonyms	Images
Berberidaceae	Mahonia	†Mahonia simplex	(Newberry) Arnold	Misc-Elk River[23] Misc-Weiser[14]	An oregon grape species.	Ilex latahensis (1932)[15] Odostemon simplex of Berry, 1934[14]
Platanaceae	Platanus	†Platanus dissecta	Lesquereux	Clarkia[26] Coeur d'Alene[1] Grand Coulee[21] Misc-Alkali Creek[14] Misc-Linson Valley[14] Misc-St. Maries[14] Spokane[9] White Bird[14]	A Platanus subg. Platanus sycamore leaf species.[26]	Acer merriami of Berry, 1929 & 1934	Platanus dissecta
		†Platanus emryi[26]	Huegele, Spielbauer, & Manchester	Emerald Creek	A Platanus subg. Platanus sycamore fruit species.	Platanus sp fruit of Ashlee, 1932
Trochodendraceae	Trochodendron	†Trochodendron rosayi[27]	Manchester, Pigg, & DeVore	Emerald Creek	A Trochodendron fruit species.
?Trochodendraceae	†Nordenskioldia	†Nordenskioldia interglacialis[28]	(Hollick) Manchester, Crane, & Dilcher	Clarkia[28] Grand Coulee[28] Spokane[8] White Bird[14]	A stem-group trochodendralean fruit species. Likely fruits of the leaf species Zizyphoides auriculata	Carpites interglacialis (1952) Carpites menthoides (1926) "Equisetum underground stems" (1926) Malva? hesperia (1926) Phyllites amplexicaulis (1926)	Nordenskioldia interglacialis
	†Zizyphoides	†Zizyphoides auriculata	(Heer) Manchester, Crane, & Dilcher	Clarkia[28] Grand Coulee[28] Misc-Arrow Junction[14] Misc-Clearwater River[14] Misc-Juliaetta[14] Misc-St Marie[14] Spokane[28] White Bird[14][28]	A stem-group trochodendralean leaf species. Likely fruits of the fruit species Nordenskioldia interglacialis	Cebatha heteromorpha (1926)[14][28] Cocculus heteromorpha (1946) Populus heteromorpha (1926)[28] Populus fairii (1926)	Zizyphoides auriculata

Superasterids - basal

Family	Genus	Species	Author	Florule	Notes	Synonyms	Images
Cornaceae	Cornus	†Cornus becki	Berry	Grand Coulee	A dogwood species.
		†Cornus latahense[1]	Chaney and Axelrod	Spokane	A dogwood species.	Cornus ovalis of Brown, 1937
Ebenaceae	Diospyros	†Diospyros oregoniana[1]	(Lesquereux) Chaney & Axelrod	Grand Coulee Spokane White Bird	A persimmon species	Diospyros andersonae (1926)	Diospyros oregoniana
	†Remberella [2]	†Remberella microcalyx[9]	(Knowlton) Manchester & Judd, 2024	Clarkia Emerald Creek Spokane Misc-Oviatt Creek	A probable ebenaceous flower.	Porana microcalyx (1929) Diospyros? microcalyx (1926)	Remberella microcalyx
Ericaceae	Arctostaphylos	†Arctostaphylos spatulata[9]	Berry	Spokane	A manzanita species Deemed incertae sedis without commentary (1959)[1]		Arctostaphylos spatulata
	Gaultheria	†Gaultheria pacifica[23]	Brown	Spokane-Brickyard	A Gaultheria species
	†Juddicarpon	†Juddicarpon benewahensis[29]	Smith & Manchester	Clarkia	A vaccinioid fruit.
	Kalmia?	†Kalmia (?) elongata[15]	Ashlee	Misc-Elk River	A Kalmia species
	Rhododendron	†Rhododendron knowltoni[9]	Berry	Spokane	A Rhododendron species	Menziesia knowltoni (1929)	Rhododendron knowltoni
	Vaccinium	†Vaccinium bonseri	Berry	Spokane	A Vaccinium species One named subspecies/variety V. b. serrulatum		Vaccinium bonseri
		†Vaccinium sophoroides	Knowlton	Coeur d'Alene	First named as a huckleberry leaf species Synonymized into Vaccinium americanum (1929)[9] Resurrected as incertae sedis (1959)[1]		Vaccinium salicoides
		†Vaccinium sophoroides	(Knowlton) Brown	Coeur d'Alene[14] Misc-Juliaetta[14] Spokane[9]	A Vaccinium species	Arctostaphylos knowltoni (1929) Cassia sophoroides (1929)[14] Diospyros princetoniana of Berry, 1929 Phyllites sophoroides (1926) Salix perplexa p. p.	Vaccinium sophoroides
Hydrangeaceae	Hydrangea	†Hydrangea knowltoni	(Berry) Chaney & Axelrod	Grand Coulee[10] Spokane[14] White Bird[14]	A hydrangea species	Euonymus knowltoni (1929)[14] Hydrangea bendirei of Knowlton, 1926, Berry, 1929, Brown, 1937 Gordonia hesperia p. p. Ternstroemites idahoensis of Berry, 1929	Hydrangea knowltoni
	Philadelphus	†Philadelphus pardeei[10]	(Knowlton) Brown	Spokane	A mock-orange species	Phyllites pardeei (1926) Phyllites peculiaris (1926)	Philadelphus pardeei
Loasaceae	Mentzelia	†Mentzelia occidentalis	(Berry) Brown	Spokane[10] Misc-Julietta[10] Misc-Potlatch River[14] White Bird[10]	A stickleaf species	Hibiscus? occidentalis (1929)	Mentzelia occidentalis
Nyssaceae	Nyssa	†Nyssa hesperia[21]	Berry	Grand Coulee Misc-Linson Valley[14] Spokane White Bird[14]	A tuplo species of the N. sylvatica complex.[30]	Magnolia spectabilis of Brown, 1938
		†Nyssa magnifica	(Knowlton) Berry	Grand Coulee Spokane	A tuplo species of the N. javanica complex.[30]	Carpites magnifica (1926)	Nyssa magnifica
Oleaceae	Fraxinus	†Fraxinus dayana[1]	Chaney & Axelrod	White Bird	An ash species.
		†Fraxinus idahoensis	Brown	Misc-Potltach Creek[20] White Bird[14][20]	A ash species.	Fraxinus? sp. of Berry, 1934
Styracaceae	Halesia	†Halesia columbiana[23]	Brown	Spokane-Brickyard	A silverbell fruit species
Theaceae	Gordonia	†Gordonia idahoensis[1]	(Knowlton) Berry	Grand Coulee[21] misc-juliaetta[14] Spokane[9] White Bird[14]	A Gordonia species.	Arbutus idahoensis (1937) Carpites paulownia (1926) Celastrus spokanensis (1929) Gordonia hesperia (1929) p. p. Laurus grandis of Knowlton 1926 p. p. Laurus princeps of Berry 1929 Myrica? idahoensis (1898) Myrica lanceolata p. p.	Gordonia idahoensis

Superasterids

Family	Genus	Species	Author	Florule	Notes	Synonyms	Images
Adoxaceae	Viburnum	†Viburnum fernquisti[9]	Berry	Coeur d'Alene Grand Coulee Spokane	A Viburnum seed morphospecies.		Viburnum fernquisti
		†Viburnum lantanafolium[9]	Berry	Spokane	A Viburnum species.	Aesculus hesperia (1929) Rhamnus idahoensis p. p.	Viburnum lantanafolium
		†Viburnum ribesiforme	LaMotte	Coeur d'Alene Grand Coulee Spokane	A Viburnum species.	Ribes fernquisti (1929)[9] Viburnum fernquisti of Brown 1937	Viburnum ribesiforme
Apiaceae	†Umbelliferospermum	†Umbelliferospermum latahense[9]	Berry	Spokane	An apiaceous winged fruit morphogenus.[31]		Umbelliferospermum latahense
Aquifoliaceae	Ilex	†Ilex fulva[1]	MacGinitie	Spokane	A holly species.

Superrosids - Basal

Family	Genus	Species	Author	Florule	Notes	Synonyms	Images
Altingiaceae	Liquidambar	†Liquidambar pachyphyllum	Knowlton	Grand Coulee Misc-Arrow Junction[14] Spokane[9] White Bird[9][14]	A sweet gum species.	Arisaema hesperia (1926)?	Liquidambar pachyphyllum
Hamamelidaceae	Exbucklandia	†Exbucklandia oregonensis	(Chaney) Brown	Coeur d'Alene[9][14] Grand Coulee[8] Misc-Cove[14] Spokane[23] White Bird[14]	An Exbucklandia species	Cercus spokanensis non Knowlton nec Brown (1937) p.p.[10] Ficus washingtonensis Knowlton (1926)[8] Meibomites lucens Knowlton (1926)[8] Meibomites knowltoni Berry (1929)[9]	Exbucklandia oregonensis
Vitaceae	Vitis	†Vitis bonseri	Berry	Coeur d'Alene[14][1] Grand Coulee[21] Misc-Arrow Junct.[14][1] Misc-Juliaetta[14][1] White Bird[14][1]	A grape species.
		†Vitis washingtonensis	(Knowlton) Brown	Coeur d'Alene[9] Grand Coulee[21] Spokane[9][32] White Bird[14] Misc-Oviat Creek	A grape species.	Acer merriami p. p. Cercis idahoensis p. p.[33][14] Cercis sp. of Ashlee, 1932 Menispermites latahensis (1929) Populus lindgreni p. p. Populus washingtonensis (1926)	Vitis washingtonensis

Superrosids - Fabids

Family	Genus	Species	Author	Florule	Notes	Synonyms	Images
Betulaceae	Alnus	†Alnus fairii	(Knowlton) Wolfe[34]	Coeur d'Alene[1] Grand Coulee[21][1] Misc-Arrow Junct.[14] Spokane[1] White Bird[1]	An alder.	Betula bryani (1937)[10] Betula nanoides (1934)[14] Betula fairii (1926)[34] Betula heteromorpha of Berry, 1931[21][1] Betula heteromorpha of Berry, 1934[14][1] Betula largei of Berry, 1931[21][1]	Betula fairii
		†Alnus largei	(Knowlton) Wolfe[34]	Coeur d'Alene[1] Grand Coulee[1] Misc-Clearwater River[14] Misc-St Maries[14] Spokane[1] White Bird[1]	A birch	Betula heteromorpha of Berry, 1931[21][1] Betula largei (1966)	Alnus largei
		†Alnus hollandiana	Jennings	Coeur d'Alene Spokane	An alder	Alnus prerhombifolia Prunus rustii p. p.	Alnus hollandiana
		†Alnus relatus	(Knowlton) Brown	Coeur d'Alene Grand Coulee Spokane White Bird	An alder	Phyllites relatus (1926) Prunus rustii non Knowlton nec. Berry (1929)	Alnus relatus
	Betula	†Betula thor	Knowlton	Spokane	A birch		Betula thor
		†Betula vera	Brown	Spokane	A birch
	Ostrya	†Ostrya oregoniana	Chaney	Spokane[1]	A hophornbeam
Celastraceae	Euonymus	†Euonymus pacificus[10]	Brown	Spokane	A wintercreeper species
Fabaceae	Caesalpinia	†Caesalpinia spokanensis[35]	(Knowlton) Herendeen & Dilcher	Clarkia Coeur d'Alene Spokane White Bird Misc - Elk River	A Caesalpinia fruit Possibly the fruits belonging to Sophora spokanensis[35]	Cercis? spokanensis (1926)[8] Cercis idahoensis (1930)[33] Cercidium hesperium (1932)[15] Gleditsia praeaquatica (1932)[15]	Caesalpinia spokanensis
	Cercis	Unnamed	Brown	Spokane[10][36]	Leaves first placed as Cercis spokanensis In need of redescription and renaming[36]	Cercis spokanensis of Brown, 1937[36]
	†Leguminosites	†Leguminosites alexanderi[9]	Berry	Spokane	A fabaceous fruit species		Leguminosites alexanderi
	Robinia?	†Robinia (?) idahoensis[15]	Ashlee	Misc-Grangerville Mtn	A fabaceous fruit species
	Sophora	†Sophora spokanensis[8]	Knowlton	Coeur d'Alene[14][1] Grand Coulee[1] Misc-Juliaetta[14] Spokane[9][1] White Bird[14]	A Sophora species. Possibly the leaves belonging to Caesalpinia spokanensis[35]	Cassia spokanensis Quercus treleasi Sophora alexanderi (1926)	Sophora spokanensis
Fagaceae	Castanea	†Castanea spokanensis	(Knowlton) Chaney & Axelrod	Grand Coulee[1] Misc-St Maries[14] Spokane[1] White Bird[14][1]	A Chestnut species	Castanea castaneaefolia of Knowlton, 1926[8] Castanea castaneaefolia of Berry, 1931[21] Castanea castaneaefolia of Berry, 1934[14] Quercus spokanensis	Castanea spokanensis
	Castanopsis	†Castanopsis perplexa	(Knowlton) Brown	Coeur d'Alene	A Chestnut species		Castanopsis perplexa
		†Castanopsis spokanensis	(Brown) Chaney & Axelrod[1]	Spokane	A chinquapin species	Tetracera spokanensis
	Fagus	†Fagus pacifica	Chaney	Misc-Moscow[14] Misc-E. of Lewiston[14] White Bird[14]	A Beech species Specimens in need of confirmation.[19]
		†Fagus washoensis	LaMotte	Grand Coulee[1] Misc-Arrow junct.[14] Misc-Linson Valley[14] Spokane[1] White Bird[14]	A Beech species	Amygdalus alexanderi (1929)[37] Ostrya oregoniana of Berry, 1934[14][1] Quercus spokanensis of Berry, 1938[1] Ulmus speciosa of Berry, 1934[14][1]
	†Pseudofagus	†Pseudofagus idahoensis[38]	Smiley & Huggins	Clarkia	A fagaceous genus
	Quercus	†Quercus axelrodi[23]	Brown	Spokane	An oak.
		†Quercus bretzi[10]	Chaney	Spokane	An oak.
		†Quercus columbiana[32]	Chaney	Misc ID Potlach Creek Poorman Creek	An oak.
		†Quercus dayana[1]	Knowlton	Spokane	An oak.
		†Quercus eoprinus	Smith	Misc-Montour[14]	An oak.	Quercus spokanensis gracilis (1934)[14]
		†Quercus mccanni[21]	Berry	Grand Coulee	An oak.		Quercus mccanni
		†Quercus payettensis	Knowlton	Coeur d'Alene[14][1] Grand Coulee[1] Misc-Clearwater River[14] Misc-E. of Lewiston[14] Misc-Julietta[14] Spokane[1] White Bird[14]	An oak.	Quercus cognatus (1926)[14] Quercus obtusa (1926) Quercus praenigra (1926) Quercus rustii (1926)	Quercus payettensis
		†Quercus pseudolyrata	Lesquereux	Grand Coulee[21] Misc-Moscow[14] Misc-Potlatch Creek Spokane	An oak.
		†Quercus simulata[10]	Knowlton	Coeur d'Alene[10][1] Grand Coulee[10][1] Misc-Arrow junct.[14] Misc-Clearwater River[14] Misc-E. of Lewiston[14] Misc-Juliaetta[14] Misc-Moscow[14] Spokane[10][1] White Bird[14][10][1]	An oak species	Laurus princeps p. p. Phyllites crustacea (1926) Quercus idahoensis (1898)[1] Quercus chaneyi (1926)	Quercus simulata
		Quercus sp.		Coeur d'Alene[14] Spokane[9] White Bird[14]	Isolated acorn nuts Not described to species		Quercus sp. acorn
		Quercus sp.		Coeur d'Alene Spokane	Isolated acorn cupules Not described to species		Quercus sp. cupule
Juglandaceae	Carya	†Carya bendirei	(Lesquereux) Chaney & Axelrod	Grand Coulee Misc-Thorn Creek White Bird	A hickory species	Juglans egregia p.p.[21]	Carya bendirei
	†Palaeocarya	†Palaeocarya olsonii	(Brown) Manchester	Misc	A Palaeocarya species	Engelhardia olsoni
	Pterocarya	†Pterocarya mixta[10]	(Knowlton) Brown	Spokane	A wingnut species
Malpighiaceae	Hiraea	†Hiraea knowltoni[13]	(Berry) Graham	Spokane	A Hiraea species.	Nyssa knowltoni of Brown, 1937[10]
Myricaceae	Comptonia	†Comptonia hesperia	Berry	Spokane	A sweet fern
	Myrica	†Myrica ashleei[32]	LaMotte	Misc-Elk River	A Myrica species.	Myrica idahoensis of Ashlee, 1932
Rhamnaceae	Paliurus	†Paliurus hesperius[39]	Berry	Clarkia? Misc-Clearwater River[14] Grand Coulee Spokane	A Paliurus species Suggested to be possible syn of †Paliurus favonii[40] That synonymy questioned.[41]		Paliurus hesperius
	Rhamnus	†Rhamnus columbiana[1]	Chaney & Axelrod	Misc - Moscow	A buckthorn species
Rosaceae	Amelanchier	†Amelanchier couleeana	(Berry) Brown	Grand Coulee[21][23] Misc-Moscow[14] Spokane[9]	A service berry species	Amelanchier dignatus of Brown, 1935 p. p. Amelanchier scudderi of Berry, 1929 Phyllites couleeanus (1931)	Amelanchier couleeana
	Cercocarpus	†Cercocarpus praeledifolius[9]	Berry	Spokane	A mountain mahogany species Placement deemed incertae sedis (1959)[1]		Cercocarpus praeledifolius
	Crataegus	†Crataegus latahensis[15]	Ashlee	White Bird	A hawthorn species
	Rubus	†Rubus idahoensis[15]	Ashlee	Misc-Grangeville Mtn	A bramble species
Salicaceae	Populus	†Populus eotremuloides	Knowlton	Misc-Arrow Junct.[14]	A cottonwood species
		†Populus lindgreni	Knowlton	Spokane-Vera[1] Misc-Orofino[23]	A cottonwood species
		†Populus voyana[1]	Chaney & Axelrod	Coeur d'Alene Spokane - Veradale	A cottonwood species
		Unnamed[9]	Berry	Spokane - Brickyard	Unnamed cottonwood species flower bracts		Populus sp.
	Salix	†Salix hesperia	(Knowlton) Condit	Grand Coulee[21] Misc-Clearwater River[14] Misc-Juliaetta[14] Misc-Moscow[14] Spokane[9] White Bird[14]	A willow species	Cassia idahoensis (1919)[14] Populus lesquereuxi of Berry, 1931 Quercus simulata of Berry, 1929 p.p. Rhus typhinoides of Knowlton, 1926 Salix florissanti of Berry, 1929 Salix florissanti of Berry, 1934 Salix inquirenda (1926) Salix inquirenda of Berry, 1934 Salix remotidens (1926)	Salix hesperia
		†Salix kempffii[15]	Ashlee	Misc-Elk River	A willow species
		†Salix knowltoni	Berry	Misc-Clearwater River[14]	A willow species
		†Salix spokanensis	(Berry) Brown	Spokane	A willow species	Rhamnus spokanensis (1929) Robinia? sp. (1926) Phyllites sp. (1926) Quercus sp. (1929) Vaccinium spokanense (1929)	Salix spokanensis
		Unnamed[9]	Berry	Spokane - Brickyard	Unnamed willow species stipules		Salix sp.
Ulmaceae	†Cedrelospermum	†Cedrelospermum lineatum	(Lesquereux) Manchester	Misc-Juliaetta[14]	An ulmaceous species.	Ulmus brownelli of Berry, 1934[14][42]
	Ulmus	†Ulmus newberryi	Knowlton	Spokane[1]	Elm species fruits. Not reassessed by Tanai & Wolfe (1977)[43]	Ulmus sp. (fruits) (1929)	Ulmus newberryi
		†Ulmus moorei	Chaney & Elias	Misc-N of Weiser[14][43]	An Elm species	Fagopsis longifolia of Berry, 1934[14][1]
		†Ulmus speciosa	Newberry	Grand Coulee[43] Spokane[43] White Bird[43] Misc-Arrow junction	An Elm species		Ulmus speciosa
	Zelkova	†Zelkova browni[43]	Tanai & Wolfe	Spokane	An Elm species	Fagopsis longifolia of Berry, 1929 Ulmus fernquisti (1926) Zelkova oregoniana (1937)	Zelkova browni

Superrosids - Malvids

Family	Genus	Species	Author	Florule	Notes	Synonyms	Images
Lythraceae	Trapa	†Trapa americana	Knowlton	Juliaetta[44]		A water caltrop species	Trapa americana
Malvaceae	†Florissantia	†Florissantia speirii	(Lesquereux) MacGinitie	Spokane	A malvalean flower.
	Tilia	†Tilia aspera	(Newberry) LaMotte	Misc-Arrow junction[14] Spokane[14]	A linden species	Platanus aspera (1883) Tilia hesperia (1929)	Tilia aspera
Meliaceae	Cedrela	†Cedrela pteraformis	(Berry) Brown	Coeur d'Alene Grand Coulee Misc-Juliaetta[14] Spokane White Bird[14]	A Cedrela.	synonymy Carpolithes pteraformis (1929) Cassia spokanensis (1929) Gordonia pteraformis (1929) Rhus merrilli of Berry, 1934[14] Sapindus armstrongi (1929) Umbellularia dayana of Berry (1929)	Cedrela pteraformis
Rutaceae	Ptelea	†Ptelea miocenica[21]	Berry	Grand Coulee[21] Spokane[9] White Bird[14]	A Ptelea species	Nyssa knowltoni (1929)	Ptelea miocenica
Sapindaceae	Acer	†Acer browni	Wolfe & Tanai	Spokane - Veradale	An Acer species
		†Acer busamarum subsp. fingerrockense	Wolfe & Tanai	Clarkia	An Acer species
		†Acer chaneyi	Knowlton	Clarkia[45] Coeur d'Alene Misc-Juliaetta[14] Grand Coulee Spokane - Veradale	An Acer leaf morphospecies Most likely the leaves belonging to Acer gigas	Acer bendirei p.p. Acer glabroides p.p. Acer merriami of Berry, 1931 Quercus pseudolyrata of Knowlton, 1926	Acer chaneyi
		†Acer gigas	Knowlton	Clarkia[45]	An Acer fruit morphospecies Most likely the fruits belonging to Acer chaneyi
		†Acer knolli	Wolfe & Tanai	Spokane	An Acer species	Acer oregonianum of Berry, 1929	Acer knolli
		†Acer latahense	Wolfe & Tanai	Spokane - Veradale	An Acer species	Acer glabroides p.p.
		†Acer medianum	Knowlton	Grand Coulee Spokane	An Acer species	Acer bolanderi p.p.
		†Acer niklasi	Wolfe & Tanai	Clarkia Spokane	An Acer species
		†Acer smileyi	Wolfe & Tanai	Clarkia	An Acer species
		†Acer tigilense	Chelebaeva	Spokane	An Acer species	Acer bendirei p.p. Acer glabroides p.p. Acer minor of Berry, 1929	Acer tigilense
		†Acer whitebirdense	(Ashlee) Wolfe & Tanai	Grand Coulee[14] Misc-Juliaetta[14] Spokane[14] White Bird[14]	An Acer species	Viburnum whitebirdensis (1932)[15] Acer florissanti of Berry, 1934[14] Acer oregonianum of Berry, 1934[14] Acer osmonti of Brown, 1937[10] Platanus dissectaBerry, 1934[14] Acer glabroides p.p.
	Dilodendron	†Dilodendron boreale[10]	Brown	Spokane	A Dilodendron species

incertae sedis

Family	Genus	Species	Author	Florule	Notes	Synonyms	Images
Incertae sedis	†Carpites	†Carpites boraginoides	Knowlton	Coeur d'Alene Grand Coulee Spokane White Bird	Seeds or nutlets of uncertain affinity Possibly boraginaceous or malvaceous?	Carpolithes hibiscoides (1935)	Carpites boraginoides
		†Carpites ginkgoides	Knowlton	Grand Coulee Spokane	A fruit/seed on a "fleshy" axis Strongly similar to modern Ginkgo biloba fruits.		Carpites ginkgoides
		†Carpites polygonoides	Knowlton	Spokane	Possible seeds or fruits Reminiscent of Rumex fruits		Carpites polygonoides
		†Carpites spokanensis	Knowlton	Grand Coulee Spokane	A seed or other reproductive organ Brown suggested as bud scales		Carpites spokanensis
	†Ozakia	†Ozakia emryi[46]	Manchester & Uemura	Misc - Emerald Creek	A winged fruit An eudicot of uncertain affinity

Fungi

The Clarkia outcrops is noted for exceptionally good palynological preservation, with a number of fungal palynomorphs preserved at the sites.^[7]

Order	Family	Genus	Species	Florule	Notes	Images
Amphisphaeriales	Cf. Apiosporaceae	indeterminate	indeterminate	Clarkia[7]		Cf. Apiosporaceae
Chaetosphaeriales	Chaetosphaeriaceae	Cf. Catenularia	indeterminate	Clarkia[7]		Cf. Catenularia sp.
Coronophorales	incertae sedis	Sphaerodes	indeterminate	Clarkia[7]		Sphaerodes sp.
Dothideomycetes	incertae sedis	Bactrodesmium	Aff. B. abruptum	Clarkia[7]		Bactrodesmium aff. abruptum
			indeterminate	Clarkia[7]		Bactrodesmium sp.
Helotiales	Helotiaceae	Bispora	indeterminate	Clarkia[7]		Bispora sp.
Hysteriales	Hysteriaceae	Cf. Acrogenospora	indeterminate	Clarkia[7]		Cf. Acrogenospora sp.
Minutisphaerales	Minutisphaeraceae	Minutisphaera	indeterminate	Clarkia[7]		Minutisphaera sp.
Pleosporales	Dictyosporiaceae	Dictyocheirospora	indeterminate	Clarkia[7]		Dictyocheirospora sp.
	Didymosphaeriaceae	Cf. Didymosphaeria	indeterminate	Clarkia[7]		Cf. Didymosphaeria sp.
	Roussoellaceae	Neoroussoella	indeterminate	Clarkia[7]		Neoroussoella sp.
Savoryellales	Savoryellaceae	Cf. Helicoon	indeterminate	Clarkia[7]		Cf. Helicoon sp.
Sordariales	Chaetomiaceae	Chaetomium	indeterminate	Clarkia[7]		Chaetomium sp.
		Trichocladium	indeterminate	Clarkia[7]		Trichocladium sp.
	Lasiosphaeriaceae	Cf. Bombardioidea	indeterminate	Clarkia[7]		Cf. Bombardioidea sp.
	Naviculisporaceae	Naviculispora	indeterminate	Clarkia[7]		Naviculispora sp.
	Neoschizotheciaceae	Cf. Cercophora	indeterminate	Clarkia[7]		Cf. Cercophora sp.
	Podosporaceae	Podospora	indeterminate	Clarkia[7]		Podospora sp.
	incertae sedis	Brachysporiella	indeterminate	Clarkia[7]		Brachysporiella sp.
Cf. Sordariales	indeterminate	indeterminate	indeterminate	Clarkia[7]		Cf. Sordariales
Tubeufiales	Tubeufiaceae	Pendulispora	indeterminate	Clarkia[7]		Pendulispora sp.
Xenospadicoidales	Xenospadicoidaceae	Spadicoides	S. sp. 1.	Clarkia[7]		Spadicoides sp. 1
			S. sp. 2.	Clarkia[7]		Spadicoides sp. 2
Xylariales	Xylariaceae	Cf. Rosellinia	indeterminate	Clarkia[7]		Cf. Rosellinia sp.
		indeterminate	indeterminate	Clarkia[7]		Xylariaceae sp.
incertae sedis	Diporothecaceae	Diporotheca	Aff. D. rhizophila	Clarkia[7]		Diporotheca aff. rhizophila
	incertae sedis	Acarocybiopsis	indeterminate	Clarkia[7]		Acarocybiopsis sp.
		Cf. Brachydesmiella	indeterminate	Clarkia[7]		Cf. Brachydesmiella sp.
		Desertella	indeterminate	Clarkia[7]		Desertella sp.
		Endophragmia	indeterminate	Clarkia[7]		Endophragmia sp.
		Endophragmiopsis	indeterminate	Clarkia[7]		Endophragmiopsis sp.
		Endophragmiella	indeterminate	Clarkia[7]		Endophragmiella sp.
		Helensiella	indeterminate	Clarkia[7]		Helensiella sp.
		Cf. Hermatomyces	indeterminate	Clarkia[7]		Cf. Hermatomyces sp.
		Hughesinia	indeterminate	Clarkia[7]		Hughesinia sp.
		Cf. Lemkea	indeterminate	Clarkia[7]		Cf. Lemkea sp.
		Melanocephala	indeterminate	Clarkia[7]		Melanocephala sp.
		Cf. Melanographium	indeterminate	Clarkia[7]		Cf. Melanographium sp.
		Phragmocephala	indeterminate	Clarkia[7]		Phragmocephala sp.
		Cf. Polytretophora	indeterminate	Clarkia[7]		Cf. Polytretophora sp.
		Seychellomyces	indeterminate	Clarkia[7]		Seychellomyces sp.

Insects

Order	Family	Genus	Species	Author/year	Florule	Notes	Images
Blattodea	Hodotermitidae	†Ulmeriella	†Ulmeriella latahensis	Snyder, 1949	Spokane[47]	A harvester termite
	Kalotermitidae	Eotermes	Indeterminate[5]	1990	Misc-Juliaetta	drywood termite Not described to species
	Stylotermitidae	†Parastylotermes	†Parastylotermes washingtonensis	(Snyder, 1931)	Spokane[48][49]	A Stylotermitid termite First named as Stylotermes washingtonensis
Coleoptera	Anthribidae	Unidentified	Unidentified	"Smiley et al. 1975"	Clarkia[16]	Two partial adults
	Carabidae	Calosoma	†Calosoma fernquisti	Cockerell, 1925	Spokane-Deep Creek[50]	A carabid ground beetle	Calosoma fernquisti
		Pterostichus	†Pterostichus fernquisti	Wickham, 1931	Spokane[51]	A carabid ground beetle
	Dascillidae	Dascillus?	†Dascillus? latahensis	Lewis, 1973	Spokane[52]	A possible soft bodied plant beetle species.
	Dytiscidae	Dytiscus	†Dytiscus latahensis	Wickham, 1931	Spokane[51]	A predaceous diving beetle
	Elateridae	Unidentified	Unidentified	"Smiley et al. 1975"	Clarkia[16]	Two partial adults
	Scarabaeidae	Unidentified	Unidentified	"Smiley et al. 1975"	Clarkia[16]	A single whole adult.
Diptera	Anisopodidae	Sylvicola	†Sylvicola carolae	(Lewis) Evenhuis, 1994	Misc-Juliaetta[53]	A wood gnat First described as Anisopus carolae (1969)
	Bombyliidae	Incertae sedis	†"Anthrax" dentoni	Lewis, 1969	Spokane[53]	First identified as an Anthrax species bee fly Redescribed as Bombyliidae incertae sedis (2015)[54]
	Bibionidae	Bibio	†Bibio latahensis	Lewis, 1969	Misc-Juliaetta[53]	A march fly
			†Bibio testeus	Lewis, 1969	Misc-Juliaetta[53]	A march fly
			Indeterminate	1969	Spokane[53]	An unidentified march fly
	Bolitophilidae?	Bolitophila?	†Bolitophila pulveris	Lewis, 1969	Misc-Juliaetta [53]	A bolitophilid gnat Considered nomen dubium
	Mycetophilidae	Boletina	Indeterminate[5]	1990	Misc-Juliaetta	An exechian fungus gnat
		Exechia	†Exechia juliaetta	Lewis, 1969	Misc-Juliaetta[53]	An exechian fungus gnat
		Rymosia	†Rymosia miocenica	Lewis, 1969	Misc-Juliaetta[53]	A rymosian fungus gnat
		Indeterminate	Indeterminate[5]	1990	Misc-Juliaetta	Unidentified mycetophiline and mycetophilid fugus gnats
	Sciaridae	Sciara	†Sciara sepulta	Lewis, 1969	Misc-Juliaetta[53]	A sciarid fungus gnat
	Tipulidae	Tipula	†Tipula latahensis	Lewis, 1969	Spokane[53]	A Tipulid cranefly
Hemiptera	Pentatomidae	Hymenarcys	†Hymenarcys cridlandi	Lewis, 1969	Spokane[53]	A pentatomid shield bug
	Saldidae	Propentacora	†Propentacora froeschneri[55]	(Lewis) Polhemus, 1985	Misc-Juliaetta	A shore bug First described as Oreokora froeschneri (1969)
	Tessaratomidae	†Latahcoris	†Latahcoris spectatus	Cockerell, 1931	Spokane[56]	A tessaratomid giant stink bug
Hymenoptera	Apidae	Bombus	†Bombus proavus	Cockerell, 1931	Spokane Misc-Juliaetta	A Bumblebee
	Formicidae	Camponotus	Indeterminate[5]	1990	Misc-Juliaetta	Unidentified carpenter ants
		Dolichoderus	Indeterminate[5]	1990	Misc-Juliaetta	Unidentified Dolichoderus species ants
		Lasius	Indeterminate[5]	1990	Misc-Juliaetta	Unidentified Lasius species ants
		Messor ?	Indeterminate[5]	1990	Misc-Juliaetta	Unidentified possible Messor species ants
		Indeterminate	Indeterminate	1931	Spokane[56]	Unidentified ants
	Ichneumonidae	Periope	†Periope ivesi	Lewis, 1969	Spokane[53]	A metopiine ichneumonid wasp
		Sphecophaga	Indeterminate[5]	1990	Misc-Juliaetta	A metopiine ichneumonid wasp
		Indeterminate	Indeterminate	1990	Misc-Juliaetta[5]	Unidentified cryptine ichneumonid wasps
		Indeterminate	Indeterminate	1990	Misc-Juliaetta[5]	Unidentified pimpline ichneumonid wasps
	Megachilidae	Indeterminate	Indeterminate	1990	Misc-Juliaetta[5]	Unidentified megachiline carpenter bees
	Tenthredinidae	Macrophya	†Macrophya adventitia	Lewis, 1969	Misc-Juliaetta[53]	A tenthredinidae sawfly
Lepidoptera	Nepticulidae	Indeterminate	Indeterminate	1969	"Not stated"[57]	A pigmy moth larva blotch-mine trace fossil Hosted on an oak leaf.
Odonata	Corduliidae	†Miocordulia	†Miocordulia latipennis	Kennedy, 1931	Spokane[58]	A corduliid dragonfly
	Macromiidae	Epophthalmia	†Epophthalmia biordinata	Lewis, 1969	Spokane[53]	A macromiid skimmer Possibly a species of Macromia[59]
	indeterminate	Indeterminate	Indeterminate	1990	Misc-Juliaetta	Unidentified dragonflies
Orthoptera	Tettigoniidae	Undescribed	Undescribed	"Smiley et al. 1975"	Clarkia[16]	Partial katydid specimens
Plecoptera	Leuctridae	Megaleuctra	†Megaleuctra jewetti	Lewis, 1969	Misc-Juliaetta[53]	A rolled-wing stonefly
Trichoptera	Limnephilidae	Limnephilus	Indeterminate	1990	Misc-Juliaetta	An unidentified northern caddisfly
		†Miopsyche	†Miopsyche alexanderi	Carpenter, 1931	Spokane[60]	A northern caddisfly
			†Miopsyche martynovi	Carpenter, 1931	Spokane[60]	A northern caddisfly
			Indeterminate	1990	Clarkia[16] Misc-Juliaetta	An unidentified northern caddisfly
	Phryganeidae	†Folindusia	†Folindusia miocenica	Berry, 1928[61]	Spokane	A phryganeid giant caddisfly larval case indusispecies	Folindusia miocenica
			†Folindusia sp.	1970	Misc-Juliaetta Spokane[62]	A phryganeid giant caddisfly larval case indusispecies
		Phryganea	†Phryganea spokanensis	Carpenter, 1931	Spokane[60]	A giant caddisfly
			Indeterminate	1990	Misc-Juliaetta	An unidentified giant caddisfly

Fish

Family	Genus	Species	Author/year	Florule	Notes	Images
Centrarchidae	Archoplites	†Archoplites clarki[6]	Smith & Miller, 1985	Clarkia	A sun fish
Leuciscidae	Gila	Unnamed[6]		Clarkia	Possibly 2 species of western chub
Salmonidae	Cf. Hucho	Unnamed[6]		Clarkia	An unnamed salmonid First described as a taimen, later noted to be similar to but not in Hucho[63]
Unidentified	Unidentified	Unidentified[9]		Spokane? Misc-Weiser[14] Misc-Juliaetta[14] Misc-N of Lewiston[14]	Isolated scales and vertebrae Suggested to be Leuciscus possibly the same as Leuciscus turneri[9]	"fish scales"

Mammals

Family	Genus	Species	Author/year	Florule	Notes	Images
Sciuridae	incertae sedis	incertae sedis	"2018"	Clarkia	The first tetrapod from Clarkia	Clarkia Sciuridae specimen Burke Museum #UWBM 113209

Algae

An initial survey of Latah Formation diatoms was conduced by Albert Mann at the behest of Frank Hall Knowlton. Based on sample material recovered from a well 0.25 mi (0.40 km) west of Mica, Washington, itself southeast of Spokane, Mann identified a large number of diatomaceous species, including 10 new species. Mann noted the diatoms appear to have lived under stressed conditions caused by caustic water, with many of the specimens showing malformed shapes or blurred ornamentations. The typical cause of this in diatoms is a high concentration of dissolved mineral salts in the water body.^[4]

Family	Genus	Species	Author/year	Florule	Notes	Synonyms	Images
Amphipleuraceae	Amphipleura	Amphipleura oregonica[4]	Grunow	Spokane	An amphipleuraceous diatom	Amphipleura pellucida var. oregonica
	Frustulia	Frustulia rhomboides[4]	(Ehrenberg) De Toni	Spokane	An amphipleuraceous diatom		Frustulia rhomboides
Aulacoseiraceae	Aulacoseira	†Aulacoseira distans[4]	(Ehrenberg) Simonsen	Spokane	A aulacoseiraceous diatom	Melosira distans
		Aulacoseira granulata[4]	(Ehrenberg) Simonsen	Spokane	A aulacoseiraceous diatom	Melosira granulata
Cavinulaceae	Cavinula	Cavinula scutiformis[4]	(Grunow ex A.Schmidt) D.G.Mann & A.J.Stickle	Spokane	A cavinulaceous diatom	Navicula scutiformis
Coscinodiscaceae	Coscinodiscus	Coscinodiscus subaulacodiscoidalis[4]	Rattray	Spokane	A coscinodiscaceous diatom		Coscinodiscus subaulacodiscoidalis
Cymbellaceae	Cymbella	Cymbella americana[4]	A.W.F.Schmidt	Spokane	A cymbellaceous diatom		Cymbella americana
		Cymbella amphicephala[4]	Näegeli	Spokane	A cymbellaceous diatom
		Cymbella flexella[4]	Kützing	Spokane	A cymbellaceous diatom	Achnanthes (Achnanthidium) flexella
		Cymbella lunula[4]	(Ehrenberg) Rabenhorst	Spokane	A cymbellaceous diatom
		Cymbella partita[4]	Mann	Spokane	A cymbellaceous diatom		Cymbella partita
		Cymbella sagittarius[4]	Mann	Spokane	A cymbellaceous diatom		Cymbella sagittarius
Eunotiaceae	Actinella	Actinella brasiliensis[4]	Grunow	Spokane	A eunotiaceous diatom
	Desmogonium	Desmogonium rabenhorstianum[4]	Grunow	Spokane	A eunotiaceous diatom
	Eunotia	Eunotia incisa[4]	Grunow	Spokane	A eunotiaceous diatom
		Eunotia parallela[4]	Ehrenberg	Spokane	A eunotiaceous diatom
		Eunotia pectinalis[4]	(Kuetzing) Rabenhorst	Spokane	A eunotiaceous diatom
		Eunotia robusta[4]	Ralfs	Spokane	A eunotiaceous diatom Varieties E. r. var. diadema & E. r. var. papilio
Fragilariaceae	Fragilaria	Fragilaria constricta[4]	(A.Cleve) Hustedt	Spokane	A fragilariaceous diatom Form Fragilaria constricta f. stricta	Fragilaria undata
		Fragilaria binalis[4]	Ehrenberg	Spokane	A fragilariaceous diatom	Tabellaria binalis
Gomphonemataceae	Gomphonema	Gomphonema acuminatum[4]	Ehrenberg	Spokane	A gomphonemataceous diatom
		Gomphonema gracile[4]	Ehrenberg	Spokane	A gomphonemataceous diatom
		Gomphonema parvulum[4]	(Kützing) Kützing	Spokane	A gomphonemataceous diatom
Melosiraceae	Melosira	Melosira biseriata[4]	(Ehrenberg) Schmidt	Spokane	A melosiraceous diatom
		Melosira lyrata[4]	Ehrenberg	Spokane	A melosiraceous diatom
		Melosira teres[4]	Brun	Spokane	A melosiraceous diatom
		Melosira undulata[4]	(Ehrenberg) Kützing	Spokane	A melosiraceous diatom
Naviculaceae	Caloneis	Caloneis westii[4]	(W.Smith) Hendey	Spokane	A naviculaceous diatom	Navicula formosa
	Navicula	Navicula americana[4]	F.W. Mills	Spokane	A naviculaceous diatom
		Navicula angusta[4]	Grunow	Spokane	A naviculaceous diatom
		Navicula bacillum[4]	Ehrenberg	Spokane	A naviculaceous diatom
		Navicula commutata[4]	Grunow ex A.Schmidt	Spokane	A naviculaceous diatom
		†Navicula contendens[4]	Mann	Spokane	A naviculaceous diatom		Navicula contendens
		Navicula elegans[4]	Grunow	Spokane	A naviculaceous diatom
		Navicula instabilis[4]	A.Schmidt	Spokane	A naviculaceous diatom
		†Navicula pauper[4]	Mann	Spokane	A naviculaceous diatom		Navicula pauper
		Navicula placentula[4]	Pantocsek	Spokane	A naviculaceous diatom
		†Navicula pontifica[4]	Mann	Spokane	A naviculaceous diatom		Navicula pontifica
		†Navicula protrudens[4]	Mann	Spokane	A naviculaceous diatom		Navicula protrudens
		†Navicula pseudoaffinis[4]	Mann	Spokane	A naviculaceous diatom		Navicula pseudoaffinis
		Navicula pseudobacillum[4]	Grunow	Spokane	A naviculaceous diatom
		Navicula pusilla[4]	Donkin	Spokane	A naviculaceous diatom
		Navicula radiosa[4]	Kützing	Spokane	A naviculaceous diatom
		†Navicula reversa[4]	Mann	Spokane	A naviculaceous diatom		Navicula reversa
		Navicula stauroptera[4]	Schumann	Spokane	A naviculaceous diatom
		Navicula subacuta[4]	(Ehrenberg) Ralfs	Spokane	A naviculaceous diatom
		†Navicula substauroneis[4]	Mann	Spokane	A naviculaceous diatom		Navicula substauroneis
		Navicula tabellaria[4]	(Ehrenberg) Kützing	Spokane	A naviculaceous diatom
		Navicula transversa[4]	A.Schmidt	Spokane	A naviculaceous diatom
		Navicula viridis[4]	(Nitzsch) Kutzing	Spokane	A naviculaceous diatom
Neidiaceae	Neidium	Neidium dubium[4]	(Ehrenberg) Cleve	Spokane	A neidiaceous diatom
		Neidium iridescens[4]	(Mann) VanLandingham	Spokane	A naviculaceous diatom	Navicula iridescens	Neidium iridescens
		Neidium iridis[4]	(Ehrenberg) Cleve	Spokane	A neidiaceous diatom	Navicula iridis
Pinnulariaceae	Pinnularia	Pinnularia gibba[4]	Ehrenberg	Spokane	A pinnulariaceous diatom	Navicula gibba
		Pinnularia gracillima[4]	W.Gregory	Spokane	A pinnulariaceous diatom	Navicula gracillima	Pinnularia gracillima
		Pinnularia major[4]	(Kützing) Rabenhorst	Spokane	A pinnulariaceous diatom	Navicula major
		Pinnularia mesotyla[4]	Ehrenberg	Spokane	A pinnulariaceous diatom	Navicula mesotyla
		Pinnularia nodosa[4]	(Ehrenberg) W.Smith	Spokane	A pinnulariaceous diatom	Navicula nodosa
		Pinnularia rupestris[4]	Hantzsch	Spokane	A pinnulariaceous diatom	Navicula rupestris
		Pinnularia subcapitata[4]	W.Gregory	Spokane	A pinnulariaceous diatom	Navicula hilseana
Stauroneidaceae	Stauroneis	†Stauroneis acutissima[4]	Mann	Spokane	A stauroneidaceous diatom		Stauroneis acutissima
		Stauroneis anceps[4]	Ehrenberg	Spokane	A stauroneidaceous diatom		Stauroneis anceps
		Stauroneis phoenicenteron[4]	(Nitzsch) Ehrenberg	Spokane	A stauroneidaceous diatom		Stauroneis phoenicenteron
Surirellaceae	Surirella	Surirella bifrons[4]	Ehrenberg	Spokane	A surirellaceous diatom
		Surirella inducta[4]	A.W.F.Schmidt	Spokane	A surirellaceous diatom
		Surirella striatula[4]	Turpin	Spokane	A surirellaceous diatom
Tabellariaceae	Tabellaria	Tabellaria fenestrata[4]	(Lyngbye) Kützing	Spokane	A tabellariaceous diatom
		Tabellaria flocculosa[4]	(Roth) Kützing	Spokane	A tabellariaceous diatom
	Tetracyclus	Tetracyclus ellipticus[4]	(Ehrenberg) Grunow	Spokane	A tabellariaceous diatom
Tetracyclus lacustris[4]		Ralfs	Spokane	A tabellariaceous diatom
incertae sedis	Diatoma	Diatoma grande[4]	W. Smith	Spokane	A diatom of uncertain familial affiliation
		Diatoma tenue var. hybrida[4]	Grunow	Spokane	A diatom of uncertain familial affiliation
		Diatoma vulgaris[4]	Bory de Saint-Vincent	Spokane	A diatom of uncertain familial affiliation	Diatoma vulgare
	Gomphogramma	Gomphogramma rupestre[4]	(Kützing) Braun in Rabenhorst	Spokane	A bacillariophyceopus diatom of uncertain affiliation	Tetracyclus rupestris
	Himantidium	Himantidium faba[4]	Ehrenberg	Spokane	A diatom of uncertain familial affiliation	Eunotia faba
		Himantidium gracile[4]	Ehrenberg	Spokane	A diatom of uncertain familial affiliation	Eunotia gracilis	Himantidium gracile
		Himantidium minus[4]	Kützing	Spokane	A diatom of uncertain familial affiliation	Eunotia minus