Mexican-sunflower

Names and Synonyms

Common Names

• Mexican-sunflower
• red-sunflower
• Mexican Sunflower
• Red Mexican Sunflower
• Red Sunflower

Scientific Names

Accepted name

Synonyms

• Helianthus speciosus
• Urbanisol tagetiflorus var. speciosus
• Tagetes rotundifolia
• Tithonia speciosa
• Urbanisol aristatus
• Urbanisol heterophyllus
• Urbanisol tagetiflorus
• Verbesina szyszylowiczii
• Leighia speciosa
• Urbanisol tagetiflorus var. flavus
• Urbanisol tagetiflorus var. normalis
• Tithonia aristata
• Tithonia heterophylla
• Tithonia macrophylla
• Tithonia tagetiflora
• Tithonia uniflora
• Tithonia vilmoriniana

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 within the class Equisetopsida. As a member of the subclass Magnoliidae and the order Asterales, it is further categorized into the family Asteraceae. Specifically, it is identified by the genus Tithonia and the species Tithonia rotundifolia.

Sources: The World Checklist of Vascular Plants (WCVP)

Distribution

This plant exhibits a diverse geographical range that spans across several continents. In Middle Europe, it can be found within the borders of Germany. Its presence extends into Eastern Europe, specifically throughout South European Russia. The species also thrives in West-Central Tropical Africa, particularly in the DR Congo. Finally, it is distributed across Northeast Tropical Africa, covering both Ethiopia and the Sudan-South Sudan region.

Sources: The World Checklist of Vascular Plants (WCVP)

Botanical Identification

Ecology

The ecology of Tithonia rotundifolia is characterized by its adaptability to disturbed environments, specifically thriving within anthropogenic areas (Área Antrópica). This species exhibits a broad vertical distribution across various landscapes, ranging from sea level up to a maximum elevation of 1000 m AMSL. Within this topographical span, the plant maintains an average elevation of 825 m AMSL, indicating a preference for mid-to-low altitude settings where human-altered habitats provide the necessary conditions for its growth and establishment.

Elevational range max:

1000 m AMSL

Elevational range mean:

825 m AMSL

Elevational range min:

0 m AMSL

Habitat :

Área Antrópica

Life history

The life history of Tithonia rotundifolia is characterized by an annual lifecycle, meaning the plant completes its entire developmental progression—from germination and vegetative growth to flowering and seed production—within a single growing season. As an annual species, it relies on the rapid production of a large quantity of seeds to ensure the continuity of the next generation before the onset of unfavorable environmental conditions. During its active phase, the plant undergoes a period of vigorous vegetative expansion, utilizing its nutrient reserves to establish a robust structure capable of supporting prolific flowering. This rapid turnover rate allows the species to colonize disturbed areas quickly, as the transition from seedling to reproductive maturity is streamlined to maximize reproductive output within its short lifespan.

Lifecycle :

annual

Morphology

The morphology of Tithonia rotundifolia is characterized by its growth form as a non-woody herb and forb, reaching a maximum plant height of approximately 2 meters. This species is primarily terrestrial in its habitat, rather than aquatic or semiaquatic, and functions as an independent organism without any parasitic tendencies. Its structural habit is described as self-supporting, behaving as a self-supporting climber rather than an obligatory liana or vine. Furthermore, it is a terrestrial plant that does not exhibit epiphytic characteristics, such as being a holoepiphyte or hemiepiphyte, maintaining its development strictly on the ground.

Aquatic :

terrestrial

Climber :

self-supporting

Epiphyte :

terrestrial

Growth form :

herb

Growth form :

forb

Parasite :

independent

Plant height max:

2 m

Woodiness :

non-woody

Physiology

The physiology of Tithonia rotundifolia is characterized by a robust vegetative structure, specifically regarding its foliar development and water storage capacity. The leaves exhibit significant morphological variability, with lengths ranging from a minimum of 7 cm to a maximum of 27 cm. In terms of lateral expansion, the leaf width fluctuates between a minimum of 4 cm and a maximum of 20 cm, providing a substantial surface area for photosynthetic activity. Despite the large size of its foliage, the plant does not exhibit succulence, indicating that it relies on standard mesophytic water management strategies rather than specialized parenchymatous tissue for internal water storage.

Leaf length max:

27 cm

Leaf length min:

7 cm

Leaf width max:

20 cm

Leaf width min:

4 cm

Succulence :

no

Reproduction

The reproduction of Tithonia rotundifolia is characterized by a specific flowering window and specialized seed development. The flowering period typically begins in April and concludes in June, though the timing can be variable across different months of the year. Following fertilization, the plant produces fruit in the form of an achene. These fruits are indehiscent, meaning they do not spontaneously split open at maturity to release their contents. The resulting seeds are notably small and lightweight, with a mean seed mass of approximately 0.009595 g, ranging from a minimum of 0.0095 g to a maximum of 0.00969 g. Regarding the movement of its progeny, the plant utilizes an anthropochorous dispersal syndrome, indicating that its seeds are spread primarily through human activity.

Dehiscence :

indehiscent

Dispersal syndrome :

anthropochorous

Flowering time :

Apr

Flowering time :

Jun

Fruit type :

achene

Seed mass max:

0.00969 g

Seed mass mean:

0.009595 g

Seed mass min:

0.0095 g

Sources: Global Inventory of Floras and Traits (GIFT)

Chemicals

Tithonia rotundifolia has 3 reported phytochemicals identified across 0 scientific publications and several other databases. The most consistently reported chemicals include Flavonoids, Tannins, tagitinin A.

Flavonoids

1. BMC complementary and alternative medicine

Tannins

1. BMC complementary and alternative medicine

tagitinin A

1. BMC complementary and alternative medicine