Buddleja thyrsoides is a lowland species endemic from southern Paraguay

Paraguay

Paraguay , officially the Republic of Paraguay , is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest. Paraguay lies on both banks of the Paraguay River, which runs through the center of the...

 to the deltas of the Río de la Plata

Río de la Plata

The Río de la Plata —sometimes rendered River Plate in British English and the Commonwealth, and occasionally rendered [La] Plata River in other English-speaking countries—is the river and estuary formed by the confluence of the Uruguay River and the Paraná River on the border between Argentina and...

 and Paraná River

Paraná River

The Paraná River is a river in south Central South America, running through Brazil, Paraguay and Argentina for some . It is second in length only to the Amazon River among South American rivers. The name Paraná is an abbreviation of the phrase "para rehe onáva", which comes from the Tupi language...

 in Brazil, Argentina

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

 and Uruguay

Uruguay

Uruguay ,officially the Oriental Republic of Uruguay,sometimes the Eastern Republic of Uruguay; ) is a country in the southeastern part of South America. It is home to some 3.5 million people, of whom 1.8 million live in the capital Montevideo and its metropolitan area...

. The species was first described and named by Lamarck

Jean-Baptiste Lamarck

Jean-Baptiste Pierre Antoine de Monet, Chevalier de la Marck , often known simply as Lamarck, was a French naturalist...

 in 1792.

Description

B. thyrsoides is a dioecious

Dioecious

Dioecy is the property of a group of biological organisms that have males and females, but not members that have organs of both sexes at the same time. I.e., those whose individual members can usually produce only one type of gamete; each individual organism is thus distinctly female or male...

 shrub 1 – 3. m tall, with tan bark, the young branches covered with white tomentum

Tomentum

Tomentum may refer to the following:*In botany, a covering of closely matted or fine hairs on plant leaves. *A network of minute blood vessels in the brain.* Tomentum in zoology are a short, soft pubescence...

. The leaves are sessile

Sessility (botany)

In botany, sessility is a characteristic of plants whose flowers or leaves are borne directly from the stem or peduncle, and thus lack a petiole or pedicel...

 or subsessile, linear or linear-lanceolate

Leaf shape

In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...

, the blade 7 – 15 cm long by 0.4 – 3 cm wide, subcoriaceous, glabrescent

Glabrousness

Glabrousness is the technical term for an anatomically atypical lack of hair, down, or similar structures...

 above, and white tomentose

Tomentose

Tomentose is a term used to describe plant hairs that are flattened and matted, forming a woolly coating known as tomentum. Often the hairs are silver or gray-colored...

 below. The fragrant white leafy

Inflorescence

An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...

 inflorescence

Inflorescence

An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...

s are 5 – 15 cm long by 2 – 3 cm wide, comprising 1 - 2 orders of branches, 0.5 – 2 cm long with cymose

Inflorescence

An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...

 clusters of 5 - 15 flowers; the tubular corollas 3 – 4 mm long.

Subspecies

Norman identifies two subspecies distinguished by narrower seeds and denser tomentum resp.:

• Buddleja thyrsoides subsp. angusticarpa
• Buddleja thyrsoides subsp. thyrsoides (synonyms= Buddleja chloroleuca Kraenzl., Buddleja salicifolia Vahl.)