MUSSELpdb
Taxonomy
Species & Genus Richness of
freshwater mussels
by Taxonomy
Species & Genus Richness of
freshwater bivalves
by Family
Geography
Species Richness & Endemism of
freshwater mussels
by Geography
Data last updated
Tue 02 June 2026
Bivalvia | Unionida | Unionoidea | Unionidae | Unioninae | Anodontini | Alasmidontina
genus Arcidens Simpson, 1900: cladomics
2 Recent valid species (3 total species)
Cladomics pages are experimental — even more so than the rest of this site!
The purpose of the cladomics pages for each genus and family-group level taxon is to provide statistics and references indicating the extent to which published phylogenetic work supports the classification used here.
The Cladomics Summary provides an overview of the number of studies that have included terminal species representing this taxon as well as an indication of how frequently it has been recovered as monophyletic.
Following the summary, the available published clades representing the taxon are listed.
For more information, visit the Cladomics FARQ (frequently asked rhetorical questions) page. Abbreviations for the various statistics are explained on the FARQ!
Cladomics Summary
number of species = 2 (3 total)
analyzed in 13 cladograms in 9 publications
maximum number of terminals in an analysis = 2 (mean = 1.62, median = 2)
Basic Monophyly
number of cladograms that test basic monophyly (i.e., more than 1 included species) = 8
maximum number of included terminals = 2, (mean = 2 median = 2)
proportion of cladograms that support basic monophyly = 0.88
Cladograms
Perkins et al., 2025 [Publ 4447], fig. 2_mtDNA-ITS
** Top Monophyly Cladogram ** ** Top Sister-Group Cladogram **
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 1.000 | 2 | 2 | 0 | 2 | 34 | 31 | 14 | ** |
+----------------- Utterbackiana
+--+
| | +-------------- Alasminota
| +--+
| | +----------- Pseudodontoideus
| +--+
| | +-------- Lasmigona
| +--+
| | +----- Pterosyna
| +--+
| | +-- Arcidens_confragosus **
--+ +--+
| +-- Arcidens_wheeleri **
|
| +-- Prolasmidonta
| +--+
| | +-- Platynaias
| +-----+
| | | +-- Ligodonta
| | +--+
| | +-- Alasmidonta
+--------+
| +-- Anodontoides
| +-----+
| | +-- Strophitus
+--+
| +----- Sulcularia
+--+
| +-- Pyganodon
+--+
+-- Utterbackia
Whelan et al., 2023 [Publ 4287], fig. 2
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 1.000 | 2 | 2 | 0 | 2 | 39 | 31 | 13 | 0.0 |
+-- Utterbackia
+--------------+
| +-- Pyganodon
|
| +----------- Utterbackiana
| |
| +--+ +-- Lasmigona
--+ | | +-----+
| | | | +-- Pseudodontoideus
| | +--+
| | | +----- Pterosyna
| | +--+
| | | +-- Arcidens_confragosus **
+--+ +--+
| +-- Arcidens_wheeleri **
|
| +----- Sulcularia
| +--+
| | | +-- Anodontoides
| | +--+
| | +-- Strophitus
+-----+
| +-- Prolasmidonta
| +--+
| | +-- Platynaias
+--+
| +-- Alasminota
+--+
+-- Alasmidonta
Campbell & Lydeard, 2026 [Publ 4810], fig. 6-14
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 0.933 | 2 | 2 | 0 | 2 | 630 | 35 | 13 | 0.0 |
+----------- Pseudodontoideus --+ | +-------- Lasmigona +--+ | +----- Pterosyna +--+ | +-- Arcidens_confragosus ** +--+ +-- Arcidens_wheeleri **
Whelan et al., 2023 [Publ 4287], fig. 3
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 1.000 | 2 | 2 | 0 | 2 | 26 | 25 | 11 | 0.0 |
+-------------------- Utterbackiana | | +-- Utterbackia --+ +--------------+ | | +-- Pyganodon | | | | +-------- Alasmidonta +--+ +-----+ | | | +----- Pseudodontoideus | | +--+ | | | +-- Arcidens_confragosus ** +--+ +--+ | +-- Arcidens_wheeleri ** | | +----------- Alasminota | | +--+ +-- Anodontoides | +-----+ | | +-- Strophitus +--+ | +----- Sulcularia +--+ | +-- Platynaias +--+ +-- Prolasmidonta
Whelan et al., 2023 [Publ 4287], fig. 4
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 1.000 | 2 | 2 | 0 | 2 | 25 | 23 | 10 | 0.0 |
+-------------------- Sulcularia | | +----------- Utterbackiana | +-----+ --+ | | +-------- Alasminota | | +--+ | | | +----- Pseudodontoideus | | +--+ +--+ | +-- Arcidens_confragosus ** | +--+ | +-- Arcidens_wheeleri ** | | +-------------- Alasmidonta +--+ | +----------- Platynaias +--+ | +-------- Strophitus +--+ | +----- Pyganodon +--+ | +-- Utterbackia +--+ +-- Anodontoides
Inoue et al., 2018 [Publ 3858], fig. 1_3a-c
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 0.455 | 2 | 20 | 0 | 2 | 103 | 14 | 9 | 0.0 |
+-- Alasmidonta_marginata
|
+-- Prolasmidonta
|
+-- Alasmidonta_undulata
|
+-- Beringiana
|
+-- Brachyanodon_kennerlyi
|
+-- Brachyanodon_nuttalliana
|
+-- Brachyanodon_oregonensis
|
+-- Arcidens_confragosus **
|
+-- Arcidens_wheeleri **
|
+-- Pterosyna
|
+--------------------------------------------------+-- Platynaias_compressa
| |
| +-- Lasmigona
| |
| +-- Platynaias_decorata
| |
| +-- Platynaias_subviridis
| |
| +-- Pyganodon_grandis
| |
| +-- Pyganodon_lacustris
| |
| +-- Pseudodontoideus
| |
| +-- Strophitus
| |
--+ +-- Utterbackia_imbecillis
| |
| +-- Utterbackia_peninsularis__1
| |
| +-- Utterbackia_peninsularis__2
|
| +-------------------------------------------------- Gonidea
| |
| | +----------------------------------------------- Reginaia
| | |
| | +----------------------------------------------- Amblema
| | |
| | | +----- Popenaias
| | | |
| | | | +-- Dromus
| | | | |
| | | | +-- Epioblasma
+--+ | | |
| +-----------------------------------------+ +-- Glebula
| | | |
| | | +-- Lampsilis_ovata
| | | |
| | | +-- Lampsilis_virescens
| | | |
| | | +-- Lemiox
| | +--+
| | +-- Obliquaria
| | |
+--+ +-- Obovaria_olivaria
| |
| +-- Obovaria_unicolor
| |
| +-- Plectomerus
| |
| +-- Potamilus_alatus
| |
| +-- Potamilus_capax
|
| +----- Uniomerus
| |
| | +-- Cyclonaias
| +--------------------------------------+ |
| | | +-- Pustulosa_pustulosa__1
| | | |
| | | +-- Theliderma
| | +--+
| | +-- Pustulosa_pustulosa__2
| | |
+--+ +-- Quadrula_quadrula
| |
| +-- Quadrula_verrucosa
|
| +----------------------------------------- Elliptoideus
| |
| | +-------------------------------------- Parvaspina
| | |
+--+ | +----------------------------------- Plethobasus
| | |
| | +----------------------------------- Eurynia
| | |
| | +----------------------------------- Hemistena
+--+ |
| +----------------------------------- Elliptio
| |
| | +-------------------------------- Pleuronaia
| | |
| | | +-- Pleurobema_cordatum
| | | +--------------------------+
+--+ | | +-- Fusconaia
| | |
| | | +-------------------------- Pleurobema_plenum
| | | |
| | | | +----------------------- Pleurobema_stabile
| | | | |
| | | | | +----- Pleurobema_pyriforme
| | +--+ | +--+
| | | | | | | +-- Pleurobema_georgianum__2
| | | | | | +--+
| | | | | +-----------+ +-- Pleurobema_athearni
| | | | | | |
+--+ | +--+ | | +----- Pleurobema_decisum
| | | | | |
| | | | +--+ +-- Pleurobema_georgianum__1
| | | | | |
| | | | +--+-- Pleurobema_hanleyianum__1
| | | | |
| | | | +-- Pleurobema_hanleyianum__2
| | | |
| | +--+ +-------------- Pleurobema_beadleianum__2
| | | |
| | | +--+ +----------- Pleurobema_strodeanum__2
| | | | | |
| | | | +--+----------- Pleurobema_rubellum
| | | | |
| | | | | +-------- Pleurobema_beadleianum__1
| | | | +--+
+--+ | | | +----- Pleurobema_taitianum
| | | +--+
| | | | +-- Pleurobema_perovatum
| +--+ +--+
| | +-- Pleurobema_strodeanum__1
| |
| | +----- Pleurobema_oviforme__6
| | |
| | +--+----- Pleurobema_clava__3
| | | |
| | | | +-- Pleurobema_oviforme__5
| | | +--+
| +--------+ +-- Pleurobema_clava__2
| |
| | +----- Pleurobema_oviforme__2
| | |
| | +----- Pleurobema_oviforme__3
| +--+
| +----- Pleurobema_oviforme__4
| |
| | +-- Pleurobema_clava__1
| +--+
| +-- Pleurobema_oviforme__1
|
| +----------------- Pleurobema_riddellii
| |
| | +-------------- Pleurobema_sintoxia__34
| | |
| | | +----------- Pleurobema_sintoxia__31
| | | |
+-----------+ | +----------- Pleurobema_sintoxia__32
| | |
| | +----------- Pleurobema_sintoxia__33
| | |
| | | +-------- Pleurobema__4
| | | |
| | | +-------- Pleurobema__5
+--+ | |
| | +-------- Pleurobema_sintoxia__2
| | |
| | +-------- Pleurobema_sintoxia__3
| | |
| | +-------- Pleurobema__8
| | |
| | +-------- Pleurobema__9
| | |
| | +-------- Pleurobema__10
| | |
| | +-------- Pleurobema_sintoxia__5
+--+ |
| +-------- Pleurobema_sintoxia__6
| |
| +-------- Pleurobema_sintoxia__7
| |
| +-------- Pleurobema_sintoxia__8
| |
| +-------- Pleurobema_sintoxia__9
| |
| +-------- Pleurobema_sintoxia__10
| |
| +-------- Pleurobema_sintoxia__11
| |
| +-------- Pleurobema_sintoxia__12
| |
| +-------- Pleurobema_sintoxia__13
| |
| +-------- Pleurobema_sintoxia__14
| |
| +-------- Pleurobema_sintoxia__15
| |
| +-------- Pleurobema_sintoxia__16
+--+
+-------- Pleurobema_sintoxia__17
|
+-------- Pleurobema_sintoxia__18
|
+-------- Pleurobema_sintoxia__19
|
+-------- Pleurobema_sintoxia__20
|
+-------- Pleurobema_sintoxia__21
|
+-------- Pleurobema_sintoxia__22
|
+-------- Pleurobema_sintoxia__23
|
+-------- Pleurobema_sintoxia__24
|
+-------- Pleurobema_sintoxia__25
|
+-------- Pleurobema_sintoxia__26
|
+-------- Pleurobema_sintoxia__27
|
+-------- Pleurobema_sintoxia__28
|
+-------- Pleurobema_sintoxia__29
|
+-------- Pleurobema_sintoxia__30
|
| +-- Pleurobema__6
+-----+
| +-- Pleurobema_sintoxia__1
|
| +-- Pleurobema__7
+-----+
| +-- Pleurobema_sintoxia__4
|
| +----- Pleurobema__3
+--+
| +-- Pleurobema__1
+--+
+-- Pleurobema__2
Inoue et al., 2014 [Publ 3635], fig. 3A
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 1.000 | 2 | 2 | 0 | 2 | 18 | 12 | 8 | 0.0 |
+----------- Pseudodontoideus
+--+
| | +-------- Lasmigona
| +--+
| | +----- Pterosyna
| +--+
--+ | +-- Arcidens_confragosus **
| +--+
| +-- Arcidens_wheeleri **
|
| +-------- Strophitus
| |
+-----+ +-- Pyganodon
| +--+
| | +-- Utterbackia
+--+
| +-- Platynaias
+--+
+-- Alasmidonta
Inoue et al., 2014 [Publ 3635], fig. 3B
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 0.750 | 2 | 2 | 0 | 2 | 6 | 5 | 2 | 0.0 |
+-------- Pyganodon_grandis | +-------- Pyganodon_cataracta | --+-------- Pyganodon_fragilis | +-------- Pyganodon | | +----- Platynaias +--+ | +-- Arcidens_confragosus ** +--+ +-- Arcidens_wheeleri **
Boyer et al., 2011 [Publ 2718], fig. 4
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 1.000 | 1 | 1 | 0 | 1 | 37 | 8 | 8 | 0.0 |
+-------------- Strophitus | | +----- Pterosyna --+ +-----+ | | | +-- Lasmigona | | +--+ +--+ +-- Arcidens_confragosus ** | | +-------- Utterbackia | | +--+-------- Alasmidonta | | +----- Pyganodon +--+ | +-- Anodontoides +--+ +-- Platynaias
Hewitt et al., 2018 [Publ 3758], fig. 5
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 1.000 | 1 | 1 | 0 | 1 | 8 | 5 | 5 | 0.0 |
+-------- Pyganodon | | +-- Platynaias --+-----+ | +-- Strophitus | | +----- Lasmigona +--+ | +-- Arcidens_wheeleri ** +--+ +-- Pterosyna
Pieri et al., 2018 [Publ 3867], fig. 3
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 1.000 | 1 | 1 | 0 | 1 | 19 | 0 | 0 | 0.0 |
+-------- Arcidens_confragosus ** | --+ +-- Quadrula | +--+ | | +-- Pustulosa +--+ | +-- Eurynia | | +--+-- Pleurobema | +-- Fusconaia
Inoue et al., 2020 [Publ 3941], fig. 3
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 1.000 | 1 | 1 | 0 | 1 | 41 | 0 | 0 | 0.0 |
+----------------------------------------------- Arcidens_confragosus ** | | +-- Pustulosa | +-----------------------------------------+ --+ | +-- Quadrula | | | | +----------- Parvaspina | | | +--+ +-----------------------------+ +-- Eurynia | | | +-----+ | | | | +-- Hemistena | | +--+ | | | +----- Pleurobema | | +--+ +--+ | +-- Pleuronaia | +--+ | +-- Fusconaia | | +-- Amblema | +-----------------------------------+ | | +-- Reginaia +--+ | +----------------------------------- Toxolasma | | +--+ +-------------------------------- Potamilus | | | | +-- Ellipsaria +--+ +--------------------------+ | | +-- Truncilla | | | | +-------------------------- Leaunio +--+ | | | +-------------------- Lampsilis_bracteata | | | | | +--+ +----------------- Lampsilis_fasciola | | | | | +--+ | +--+ +-------------- Lampsilis_ornata | | | | | | +--+ +-- Lampsilis_ovata | | | +--------+ | | | | +-- Lampsilis_cariosa | | +--+ | | | +-------- Lampsilis_cardium__3 +--+ +--+ | | +----- Lampsilis_cardium__2 | +--+ | | +-- Lampsilis_satura | +--+ | +-- Lampsilis_cardium__1 | | +-- Lampsilis_higginsii | +--------------+ | | +-- Ortmanniana +-----+ | +-------------- Lampsilis_teres | | +--+ +-- Lampsilis_radiata | +--------+ | | +-- Lampsilis_siliquoidea +--+ | +-------- Lampsilis_bergmanni +--+ | +----- Lampsilis_hydiana +--+ | +-- Lampsilis_virescens +--+ +-- Lampsilis_straminea
Inoue et al., 2020 [Publ 3941], fig. 4
| iT | tT | bi | riS | oT | roT | roS | iD | |
| 1.000 | 1 | 1 | 0 | 1 | 40 | 0 | 0 | 0.0 |
+-------------------------------------------------- Arcidens_confragosus ** | | +-- Pustulosa --+ +--------------------------------------------+ | | +-- Quadrula | | | | +-------------------------------------------- Reginaia +--+ | | | +----------- Parvaspina | | | | | +-----------------------------+ +-- Eurynia +--+ | | +-----+ | | | | +-- Hemistena | | +--+ | | | +----- Pleurobema | | +--+ +--+ | +-- Pleuronaia | +--+ | +-- Fusconaia | | +-------------------------------------- Amblema | | +--+ +----------------------------------- Toxolasma | | +--+ +-------------------------------- Ellipsaria | | +--+ +----------------------------- Truncilla | | | | +-------------------------- Potamilus +--+ | | | +----------------------- Leaunio | | | +--+ | +----------------- Lampsilis_bracteata | | | | | +--+ +-- Lampsilis_ornata | | | | +-----------+ +--+ | | | +-- Lampsilis_fasciola | | +--+ | | | +----------- Lampsilis_ovata | | +--+ | | | +-------- Lampsilis_cardium__3 | | +--+ +--+ | +----- Lampsilis_cardium__2 | +--+ | | +-- Lampsilis_satura | +--+ | +-- Lampsilis_cardium__1 | | +-------------- Lampsilis_teres | | | | +-- Lampsilis_higginsii +-----+ +--------+ | | +-- Ortmanniana | | +--+ +-- Lampsilis_radiata | +-----+ | | +-- Lampsilis_siliquoidea | | +--+ +-- Lampsilis_hydiana | +--+ | | +-- Lampsilis_bergmanni +--+ | +-- Lampsilis_virescens +--+ +-- Lampsilis_straminea
