Rattleweed

Names and Synonyms

Common Names

• Big Yellow Popbush
• devil-bean
• rattlebox
• wedge-leaf crotalaria
• wedge-leaf rattlepod
• Rattleweed
• Rattlepod

Scientific Names

Accepted name

Regional and Traditional Names

Sources: Wikidata, Catalogue of Life

Taxonomical Classification

This plant belongs to the kingdom Plantae and is classified under the phylum Streptophyta and class Equisetopsida. Within the subclass Magnoliidae, it falls under the order Fabales and the family Fabaceae. It is specifically identified by the genus Crotalaria, with the species name retusa.

Sources: The World Checklist of Vascular Plants (WCVP)

Distribution

This plant exhibits a broad geographical distribution across several distinct regions. Within the Macaronesian islands, it can be found specifically in Cape Verde. Its presence extends significantly into West Tropical Africa, where it inhabits multiple countries. Specifically, it is documented in Benin, Burkina, and the Gambia. Furthermore, its range includes the coastal territory of Ghana.

Sources: The World Checklist of Vascular Plants (WCVP)

Botanical Identification

Ecology

The ecology of Crotalaria retusa is characterized by its broad adaptability across diverse environmental conditions and a wide altitudinal distribution. It thrives in a variety of habitats, ranging from disturbed anthropic areas (Área Antrópica) to more complex natural ecosystems such as Carrasco, Cerrado (latu sensu), and coastal Restinga formations. This species exhibits significant vertical plasticity, occupying an elevational range that extends from sea level (0 m AMSL) up to a maximum altitude of 2450 m AMSL.

Elevational range max:

2450 m AMSL

Elevational range min:

0 m AMSL

Habitat :

Área Antrópica, Carrasco, Cerrado (lato sensu), Restinga

Genetics

The genetics of Crotalaria retusa are characterized by a specific chromosomal configuration that defines its cellular structure and reproductive biology. The species possesses a chromosome number of 16, providing the fundamental genetic blueprint for its development and phenotypic expression. Furthermore, this plant exhibits a diploid ploidy level of 2, indicating that its somatic cells contain two complete sets of chromosomes. This chromosomal stability and diploid nature are central to its genetic inheritance patterns and evolutionary lineage within the Fabaceae family.

Chromosome number :

16

Ploidy :

2

Life history

The life history of Crotalaria retusa is characterized by its classification as an annual plant, meaning it completes its entire developmental cycle—from germination and vegetative growth to flowering and seed production—within a single growing season. As a therophyte, its life form is defined by its strategy of surviving unfavorable environmental conditions through the production of seeds, which remain dormant until the onset of favorable conditions. This survival mechanism ensures that the species can persist in its habitat despite seasonal shifts, relying on the transient presence of its ephemeral aerial parts to reproduce before the plant dies back at the end of its annual cycle.

Life form :

therophyte

Lifecycle :

annual

Morphology

The morphology of Crotalaria retusa is characterized by its growth form as a non-woody herb or subshrub. This terrestrial plant grows in an erect shoot orientation and is self-supporting, rather than being a liana, vine, or climber. In terms of stature, it typically reaches a mean height of 0.85 m, though individual specimens vary in size, ranging from a minimum of 0.5 m to a maximum height of 1.5 m. As an independent species, it does not function as a parasite or an epiphyte, maintaining a strictly terrestrial life habit.

Aquatic :

terrestrial

Climber :

self-supporting

Epiphyte :

terrestrial

Growth form :

herb

Growth form :

subshrub

Parasite :

independent

Plant height max:

1.5 m

Plant height mean:

0.85 m

Plant height min:

0.5 m

Shoot orientation :

erect

Woodiness :

non-woody

Physiology

The physiology of Crotalaria retusa is characterized by several distinct morphological and metabolic adaptations, including a nitrogen-fixing capability that allows it to thrive in nutrient-poor soils through symbiotic relationships. Its photosynthetic process follows the C3 pathway, which governs its carbon assimilation and energy production. The plant's foliage exhibits significant variability in dimensions, with leaf lengths ranging from a minimum of 3.3 cm to a maximum of 9.2 cm, while leaf widths vary between 1 cm and 3.8 cm. Furthermore, the species does not exhibit succulence, maintaining a standard leaf structure rather than specialized water-storing tissues.

Leaf length max:

9.2 cm

Leaf length min:

3.3 cm

Leaf width max:

3.8 cm

Leaf width min:

1 cm

Nitrogen fixer :

yes

Photosynthetic pathway :

C3

Succulence :

no

Reproduction

The reproduction of Crotalaria retusa is characterized by a versatile phenological cycle, with flowering and fruiting periods that can occur throughout the year, beginning as early as April. The plant produces violet-colored flowers that typically measure between 1.7 cm and 2.4 cm in length. Following pollination, the plant develops fruit in the form of a pod, which ranges in length from 3 cm to a maximum of 4 cm. These pods are dehiscent, meaning they split open at maturity to facilitate seed release. Each fruit contains a significant number of seeds, typically ranging from 11 to 100 per pod. The seeds themselves are relatively small, with a maximum length of 4.5 mm and a mean mass of approximately 0.02612 g (varying from a minimum of 0.01336 g to a maximum of 0.03638 g). Dispersal is primarily anemochorous, relying on wind to transport the seeds to new locations.

Dehiscence :

dehiscent

Dispersal syndrome :

anemochorous

Flower colour :

violet

Flower length max:

2.4 cm

Flower length min:

1.7 cm

Flowering time :

Apr

Fruit length max:

4 cm

Fruit length min:

3 cm

Fruit type :

pod

Fruiting time :

Apr

Seed length max:

4.5 mm

Seed mass max:

0.03638 g

Seed mass mean:

0.02612 g

Seed mass min:

0.01336 g

Seeds_per_fruit :

11-100

Sources: Global Inventory of Floras and Traits (GIFT)

Chemicals

Crotalaria retusa has 8 reported phytochemicals identified across 0 scientific publications and several other databases. The most consistently reported chemicals include monocrotaline, INDICAN, Isatinecine, Monocrotaline N-oxide, RETRONECINE.

monocrotaline

1. Dr. Duke
2. FEMS microbiology letters

INDICAN

1. Dr. Duke

Isatinecine

1. Dr. Duke

Monocrotaline N-oxide

1. Dr. Duke

RETRONECINE

1. Dr. Duke

Retusamine

1. Dr. Duke

Retusin

1. Dr. Duke

SENECIONINE

1. FEMS microbiology letters

Activities

Crotalaria retusa has 15 reported activities identified across 0 scientific publications and several other databases. The most consistently reported activities include ACE-Inhibitor, Abortifacient, Antibacterial, Antifeedant, Antileukemic.

ACE-Inhibitor

1. Dr. Duke

Abortifacient

1. Dr. Duke

Antibacterial

1. Asian Pacific journal of tropical medicine

Antifeedant

1. Dr. Duke

Antileukemic

1. Dr. Duke

Antioxidant

1. Asian Pacific journal of tropical medicine

Antitumor

1. Dr. Duke

Carcinogenic

1. Dr. Duke

Cardiodepressant

1. Dr. Duke

Cytotoxic

1. Dr. Duke

Medicinal Uses

Crotalaria retusa has 1 reported medicinal uses identified across 0 scientific publications and several other databases. The most consistently reported uses include chromosomal aberrations.

Most Reported Uses

Preparations