Camissonia scapoidea (Torr. & A.Gray) P.H.Raven subsp. scapoidea

  • Authority

    Raven, Peter H. 1969. A revision of the genus Camissonia (Onagraceae). Contr. U. S. Natl. Herb. 37: 161-396.

  • Family

    Onagraceae

  • Scientific Name

    Camissonia scapoidea (Torr. & A.Gray) P.H.Raven subsp. scapoidea

  • Type

    Type: Clay hills, probably near the rendezvous of 1834, on Ham's Fork of the Green River, Sweetwater County, Wyoming, 22 June to 2 July 1834, T. Nuttall (NY; isotypes BM, GH). See Raven, Univ. Calif. Publ. Bot. 34: 93. 1962.

  • Description

    Deprecated: mb_convert_encoding(): Handling HTML entities via mbstring is deprecated; use htmlspecialchars, htmlentities, or mb_encode_numericentity/mb_decode_numericentity instead in /home/emu/nybgweb/www-dev/htdocs/science-dev/wp-content/themes/nybgscience/lib/VHMonographsDetails.php on line 179

    Description - Leaves usually simple, more rarely with a few reduced lateral leaflets, the blades narrowly ovate to ovate, often cordate at the base, to 5.5 cm. long and 3 cm. wide, subglabrous, very rarely villous on both surfaces, the oil cells below pale yellowish brown, rarely darker. Petals acute, 1.7-5 mm. long, 1.5-3.5 mm. wide, often red-dotted near the base. Filaments of the episepalous stamens 1-4 mm. long, those of the epipetalous ones 0.5 2.5 mm. long; anthers 0.5-1.9 mm. long, glabrous or ciliate. Style 2.5-9 mm. long. Capsule (1-) 1.5-3 cm. long; pedicel 5-18 mm. long. Gametic chromosome numbers n=7, 14. Autogamous.

  • Discussion

    Camissonia scapoidea subsp. scapoidea grows sympatrically with C. eastwoodiae and in the same vicinity as the ecologically distinct C. walkeri subsp. walkeri. It is highly variable, as would be expected in such widely ranging, principally autogamous entity. Both diploid and tetraploid populations occur in this taxon. The first series of tetraploids I studied (Univ. Calif. Publ. Bot. 34: 38-39. 1962), from Emery County, Utah, was growing with C. eastwoodiae and diploid plants of C. scapoidea subsp. scapoidea. At the time, it seemed possible that these tetraploids might have had an allopolyploid origin between the two diploids. It seemed even more likely, however, that they were autotetraploids derived from diploid C. scapoidea subsp. scapoidea, from which they were morphologically almost indistinguishable. This possibility is now considerably strengthened by the discovery of a tetraploid individual in Sweetwater County, Wyoming, along Interstate Hwy. 80, 4.8 miles southwest of junction with U.S. Hwy. 30N, R19544. This locality is some 150 miles north of the nearest station for Camissonia eastwoodiae. The plant examined formed 14 pairs of chromosomes, like the individuals from Utah studied earlier. A diploid individual was likewise found in southwestern Wyoming, 1.7 miles west of Fort Bridger, Uinta County, Mosquin & Mulligan 5128. These two chromosome counts constitute the first from the northern portion of the range of the subspecies and suggest the necessity for further chromosome counts of this taxon before its cytological pattern of variation can properly be assessed.