  Amsinckia intermedia
Fischer & Meyer
Kern Co., Bitter Creek Natl. Wildlife Refuge, Mar 2010.
Calyx generally 4 or 5-lobed; corolla ~ 8 mm long. Mericarps 1-4,
turning brown, with many sharply raised, white, transversely oriented,
wrinkles (sharply rugose ridges). |
  Amsinckia
douglasiana
A. DC.
Kern Co., Bitter Creek Natl. Wildlife Refuge, Mar 2010.
Calyx generally 4-lobed; corolla ~ 8 mm long. Mericarps cobblestoned
without transverse rugose ridges.
Occurring with A. vernicosa |
  
Amsinckia eastwoodiae
MacBride
Foothill Grassland, Mariposa Co., CA
Spjut 16219, Mar 2008 |
|
    
Amsinckia eastwoodiae
Foothill herb-grassland, Kern Co., CA, Mar 2010. Comparison of two
forms, one with broad leaves, larger flowers (17 mm long), longer sepals,
stamens inserted at base of corolla limb, abortion in development of
mericarps, one or none, and the other with corolla ~15 mm long, stamens
inserted slightly below the limb on upper part of corolla tube, and with 4
mericarps, the mericarps with slightly raised wavy wrinkles..
|

Amsinckia gloriosa
CA:
Kern Co. Elkhorn Plain, March 2009 |
|
   
Amsinckia gloriosa
CA:
Kern Co. Elkhorn Plain, March 2010. Calyx 3-lobed, densely rusty
pubescent, corolla ~10 mm long, young mericarps cobblestoned.
Rusty pubescence a key character state in Munz, A California Flora
(1959) and in Abrams, Illustrated Flora of the Pacific States
(1951). Corolla length also okay in Munz (1959) and Abrams (1951).
Included under A. douglasiana in Abrams (1951), treated as a
variety of A. tessellata in the Jepson Manual, recognized as a
distinct species in Munz (1959).
|
 
Amsinckia gloriosa
Eastwood ex Suksdorf
CA:
Kern Co. Elkhorn Plain, March 2010. Calyx 4-lobed, corolla ~10
mm long, young mericarps cobblestoned
|
|

Amsinckia intermedia
Fischer & Meyer
CA: Kern Co. Kern River Canyon,
March 2009, Photo by Susan Spjut.
Corolla tube well-exserted from calyx. |
  
Amsinckia intermedia
Field in
Bakersfield, CA
March 2005
Stems with scattered soft hairs, but not bristly.
Lower photo shows close-up of
calyx with 5 sepals enclosing a microbasarium of four mericarps. the
mericarp surface with sharply raised transverse rugose ridges and
tuberculate between ridges |

Amsinckia intermedia
Transverse Ranges, Tehachapi
Spjut 15192, Apr 2003
Stem mostly glabrous, which agrees with diagnosis in Munz, A California
Flora (1959). |
 
Amsinckia intermedia
CA: Kern Co. Kern River Canyon
March 2009. Wrinkled mericarps |
     
Amsinckia intermedia. Two similar specimens collected
along Mill Creek Trail, Kern Co., California, Apr 2010. Corollas ~12
mm long in both, 5-lobed calyx, the lobes slightly broader in one, longer
in the other. Main difference is the mericarps, tuberculate in left
specimen, A. intermedia var. californica (Suksdorf) Jepson &
Hoover, transversely rugose in right specimen, A. intermedia var.
intermedia. See Twisselmann, A Flora of Kern County,
California in Moe, A Key to Vascular Plant Species of Kern County,
California (CNPS, 1995), and illustration in Jepson, A California
Flora (1943, Vol. 3, Pt. 2). |
  
Amsinckia douglasiana
and A. intermedia,
mixed.
CA:
Kern Co. Wind Wolves Preserve.
March 2009. Corolla tube scarcely exserted from calyx |
|
|
 
Amsinckia lycopsoides Lehm.
San Joaquin Valley, Temblor Range, CA, Mar 2010. The smaller
understory plants among the larger A. glorisoa.
Small white tufts of hairs visible at base of each corolla lobe. Stamens
inserted near base of floral tube. |
  
Amsinckia menziesii
(Lehm.) Nels. & Macbride
CA: Kern Co. Kern River Canyon
March 2009. Stems bristly hairy; corolla tube scarcely exserted from calyx.
Mericarps with sharply raised transverse winkles on upper half, granular
along medial ridge, and papillate. |
|
|
  
Amsinckia
sp.
Kern Co., Bitter Creek Natl. Wildlife Refuge, Mar 2010.
Calyx generally 4 or 5-lobed; corolla ~ 8 mm long. Mericarps 1-4,
turning brown, shiny, with raised longitudinal ridges along margins and
dorsal median, and with low rounded bumps (papillae) .between margins. |
|
|

Amsinckia tessellata
A. Gray
Kern Co., Mojave, CA
Spjut 15172, Mar 2003 |
 
Amsinckia tessellata
A. Gray
Kern Co., Mojave Desert
Jawbone Canyon, CA
20 Apr 2011 |

Amsinckia desert (A. tessellata)
Mohave C., AZ, Apr 2008 |

Amsinckia tessellata
Field in southern Great Valley,
Bakersfield, CA
March 2005 |
|
|
|
 
Amsinckia vernicosa
Hook. & Arn. var. vernicolsa
Kern Co., Bitter Creek Natl. Wildlife Refuge, Mar 2010.
Calyx generally 5-lobed |
|
|
National
Toxicology Program. Related Articles, Links Toxicology and
carcinogenesis studies of riddelliine (CAS No. 23246-96-0) in F344/N rats
and B6C3F1 mice (gavage studies). Natl. Toxicol. Program Tech. Rep. Ser. 2003
May;(508): 1–280. “Riddelliine belongs to a class of toxic
pyrrolizidine alkaloids and is isolated from plants of the genera
Crotalaria, Amsinckia, and Senecio that grow in the western
United States. Cattle, horses, and sheep that ingest these plants succumb
to their toxic effects. Riddelliine residues have been found in meat,
milk, and honey, and the plants may contaminate human food sources.
Riddelliine was nominated for study by the Food and Drug Administration
because of its potential for human exposure and its economic impact on the
livestock industry and because the toxicity of other pyrrolizidine
alkaloids suggests riddelliine may be carcinogenic. Male and female F344/N
rats and B6C3F1 mice received riddelliine (approximately 92% pure) by
gavage. Female rats and male and female mice were dosed for 2 years; due
to high mortality, the study in male rats was terminated at week 72. In
vitro genetic toxicology studies were conducted in Salmonella typhimurium
and in cultured Chinese hamster ovary (CHO) cells. In addition,
riddelliine was evaluated in vivo for induction of micronuclei in mouse
bone marrow and peripheral blood erythrocytes and for induction of S-phase
DNA synthesis and unscheduled DNA synthesis in the liver of rats and mice.
Riddelliine-induced DNA adduct levels were determined in liver tissue
obtained from female rats admininstered riddelliine for 3 or 6 months.
2-YEAR STUDY IN RATS: Groups of 50 male and 50 female rats were
administered 0 or 1 mg riddelliine/kg body weight in sodium phosphate
buffer by gavage 5 days per week; additional groups of 50 female rats
received 0.01, 0.033, 0.1, or 0.33 mg/kg. A wide dose range was used in
female rats to better characterize the dose-response curve. Females were
dosed for 105 weeks; due to high mortality, male rats were terminated at
week 72. All but three 1 mg/kg males died before week 70, and all 1 mg/kg
females died before week 97. Mean body weights of 1 mg/kg males and
females were less than those of the vehicle controls throughout most of
the study. The only clinical finding related to riddelliine administration
was a general debilitation of the animals prior to death. Hemangiosarcomas
were present in the liver of 86% of males and 76% of females in the 1
mg/kg groups, and this neoplasm was considered the cause of the large
number of early deaths in these groups. The incidences of hepatocellular
adenoma and mononuclear cell leukemia in 1 mg/kg males and females were
significantly increased. Nonneoplastic lesions related to riddelliine
treatment occurred in the liver and kidney of males and females. Analyses
of liver tissue from female rats treated with riddelliine for 3 or 6
months yielded eight DNA adducts; these were the same as DNA adducts
formed in vitro by the metabolism of riddelliine by human liver microsomes
in the presence of calf thymus DNA. 2-YEAR STUDY IN MICE: Groups of 50
male and 50 female mice were administered riddelliine in sodium phosphate
buffer by gavage at doses of 0 or 3 mg/kg, 5 days per week, for 105 weeks;
additional groups of 50 male mice received 0.1, 0.3, or 1 mg/kg for 105
weeks. A wide dose range was used in male mice to better characterize the
dose-response curve. Survival of males and females administered 3 mg/kg
was significantly less than that of the vehicle controls. Mean body
weights of 3 mg/kg mice were less than those of the vehicle controls
throughout most of the study. Hemangiosarcomas of the liver were present
in 62% of males in the 3 mg/kg group. The incidences of hepatocellular
neoplasms occurred with negative trends in male mice and were
significantly decreased in 3 mg/kg females. The incidences of
alveolar/bronchiolar neoplasms in 3 mg/kg females were significantly
increased. Nonneoplastic lesions related to riddelliine administration
occurred in the liver and kidney of males and females and in the lung and
arteries (multiple tissues) of females. GENETIC TOXICOLOGY: Riddelliine
was mutagenic in S. typhimurium strain TA100 with, but not without, S9
activation; no significant mutagenic activity was detected in strain TA98
or TA1535,ed in strain TA98 or TA1535, with or without S9. A small,
dose-related increase in mutant colonies seen in strain TA97 with S9 was
judged to be equivocal. Riddelliine induced sister chromatid exchanges in
cultured CHO cells with and without S9. Chromosomal aberrations were
induced in CHO cells only in the presence of S9. Following 4 or 13 weeks
of daily gavage treatment with riddelliine, no increases in the frequency
of micronucleated erythrocytes were noted in the peripheral blood of male
or female B6C3F1 mice. Use of a single intraperitoneal injection protocol,
however, produced a small but significant increase in the frequency of
micronucleated eryth-rocytes in peripheral blood of male Swiss mice 48
hours after injection; bone marrow analysis 24 hours after injection
demonstrated a small but insignificant increase in the frequency of
micronuclei. Unscheduled DNA synthesis was detected in cultured
hepatocytes from male and female rats and mice following 5 or 30 days of
riddelliine treatment by gavage. In addition, an S-phase DNA synthesis was
observed in cultured hepatocytes of male and female rats treated for
either time period. CONCLUSIONS: Under the conditions of these studies,
there was clear evidence of carcinogenic activity of riddelliine in male
and female F344/N rats based primarily on increased incidences of
hemangiosarcoma in the liver. The increased incidences of hepatocellular
adenoma and mononuclear cell leukemia in male and female rats were also
considered to be treatment related. There was clear evidence of
carcinogenic activity of riddelliine in male B6C3F1 mice based on
increased incidences of hemangiosarcoma in the liver. There was clear
evidence of carcinogenic activity in female B6C3F1 mice based on increased
incidences of alveolar/bronchiolar neoplasms. Administration of
riddelliine by gavage resulted in nonneoplastic lesions in the liver and
kidney of male and female rats; the liver and kidney of male and female
mice; and the lung and arteries (multiple tissues) of female mice.
Decreased incidences of hepatocellular neoplasms in male and female mice
were related to riddelliine administration.” |
|