Posoqueria longiflora

{{short description|Species of flowering plant}}

{{Speciesbox

|name = Posoqueria longiflora

|image = Posoqueria longiflora (7090319193).jpg

|status = LC

|status_system = IUCN3.1

|status_ref = {{R|IUCN}}

|genus = Posoqueria

|species = longiflora

|authority = Aubl.{{R|POWO}}

|synonyms =

• Kyrtanthus longiflorus {{small|(Aubl.) J.F.Gmel.}}
• Solena longiflora {{small|(Aubl.) Willd.}}
• Tocoyena undulatifolia {{small|A.Rich.}}
• Posoqueria acuminata {{small|Mart.}}
• Willdenovia schreberi {{small|J.F.Gmel.}}

|synonyms_ref = {{R|POWO}}

}}

Posoqueria longiflora (common name needle flower) is a shrub to {{cvt|2|m}} height in the family Rubiaceae found in rainforests of northern South America. It is most noteworthy for its tubular, pure white, flowers which can be up to {{cvt|32|cm}} in length while not over 2 mm diameter,{{cite book | last= Fayaz | first=Ahmed | date=2011 | title= Encyclopedia of Tropical Plants | location= Buffalo, N.Y. | publisher= Firefly Books |page= 580 }}{{Verify source|reason=images of flowers show they are only a fraction of this length|date=June 2025}} a 160 fold ratio of length to width, the greatest such ratio found among dry land (non-aquatic) plants. It is pollinated by a sphinx moth, possibly Amphimoea walkeri (Sphingidae) which has a {{cvt|28|cm}} tongue or proboscis.{{ cite journal | last= Amsel | first= H. C. | date= 1938 | title= Die Schwarmer Mil Clem Langsten Russel | journal= Entomolog. Rundsch. |volume= 55 | issue= 15 | pages= 165–167}}

When a sphinx moth inserts its proboscis into the flower, it touches a trigger mechanism which causes the four lateral stamens (two pairs) to move away from the center, while the middle stamen lunges forward like a catapult coating the lower surface of the moth with pollen{{cite journal | last1= Kainulainen | first1= Kent | last2= Razafimandimbison |first2= Sylvain | date= October 2013 |title= Phylogenetic Relationships and New Tribal Delimitations...etc | journal= Bot. J. Linn. Soc. | volume= 173 | issue= 3 | pages=387–406 | doi= 10.1111/boj.12038 | doi-access= free }}{{Failed verification|reason=There is no mention of moths of any sort in this paper |date=March 2025}} to pollinate the stigma of the next flower visited. The role of the lateral stamens remains unclear.