Stenocorus schaumii is a species of beetle from Cerambycidae family that is 17 - .
 The species are either black or brownish-red coloured.
 Just like other members of the genus, the species have wide shoulders and tuberculated sides of the pronotum, with wrinkled elytron.
 Their larvae feed on "Fraxinus", maple, and other hardwood plants.
The rowans or mountain-ashes are shrubs or trees in the genus "Sorbus" of the rose family Rosaceae.
 They are native throughout the cool temperate regions of the Northern Hemisphere, with the highest species diversity in the mountains of western China and the Himalaya, where numerous apomictic microspecies occur.
 The name "rowan" was originally applied to the species "Sorbus aucuparia" and is also used for other species in the "Sorbus" subgenus "Sorbus".
 Rowans are unrelated to the true ash trees, which belong to the genus "Fraxinus", family Oleaceae, though their leaves are superficially similar.
Fraxinus dimorpha is a species of ash tree native to Morocco and Algeria in Northern Africa.
 An example occurrence of "F. dimorpha" is the Ourika River Valley, which is also the sole location within the High Atlas Range where the endangered primate Barbary macaque, "Macaca sylvanus" is known to occur, is the southernmost species of the genus in the world.
Alphitonia is a genus of arborescent flowering plants comprising about 20 species, constituting part of the buckthorn family (Rhamnaceae) of the rosid eudicots.
 They occur in tropical regions of Southeast Asia, Oceania and Polynesia.
 These are large trees or shrubs.
 In Australia, they are often called "ash trees" or "sarsaparilla trees".
 This is rather misleading however; among the flowering plants, "Alphitonia" is not closely related to the true ash trees ("Fraxinus" of the asterids), and barely at all to the monocot sarsaparilla vines ("Smilax").
Calycanthus (sweetshrub) is a genus of flowering plants in the family Calycanthaceae, endemic to North America.
 The genus includes two to four species depending on taxonomic interpretation; two are accepted by the "Flora of North America".
Fraxinus , English name ash, is a genus of flowering plants in the olive and lilac family, Oleaceae.
 It contains 45–65 species of usually medium to large trees, mostly deciduous though a few subtropical species are evergreen.
 The genus is widespread across much of Europe, Asia and North America.
Fraxinus anomala is a species of ash tree known by the common name single-leaf ash.
 It is native to the southwestern United States and northern Mexico, where it grows in a number of habitats including desert scrub and chaparral.
 It is unusual in the genus in that some (though not all) specimens have simple leaves instead of the pinnate leaves more characteristic of the group.

Question: Which genus has more species, Fraxinus or Calycanthus?
Answer: Fraxinus