| Aquilegia longissima | |
|---|---|
 | |
Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Order: | Ranunculales |
| Family: | Ranunculaceae |
| Genus: | Aquilegia |
| Species: | A. longissima |
| Binomial name | |
| Aquilegia longissima | |
| Synonyms[2] | |
Aquilegia coerulea f.longissima(A.Gray)Rapaics | |
Aquilegia longissima, thelong-spur columbine[3] orlong-spurred columbine,[1] is a rareperennialflowering plant in the familyRanunculaceae that is native to northernMexico,Texas, andArizona.[2]
Aquilegia longissima grows to 25–90 cm (9.8–35.4 in) tall, withbiternate basal leaves measuring 20–45 cm (7.9–17.7 in) across, usually shorter than the stems. The flowers are erect with pale yellowlanceolate sepals of 25–40 mm (0.98–1.57 in) length, spreading at right angles to the petals. The petals are yellow, spoon-shaped, and 15–30 mm (0.59–1.18 in) long.[3]
The most remarkable feature of the species is the extremely longnectar spurs, measuring 72–180 mm (2.8–7.1 in), straight, evenly tapered, and very slender in shape, and usually hanging straight down.[3] They are the longest spurs of anyeudicot.[4][5]
In the original species description by Asa Gray in1883,Aquilegia longissima is distinguished from the shorter-spurred golden columbineAquilegia chrysantha by the narrowspatulate petals and long, slender spurs hanging straight down.[6]
The species is part of aclade containing all theNorth American species of columbines, that likely split from their closest relatives inEast Asia in the mid-Pliocene, approximately 3.84 million years ago.[7]
Thespecific epithetlongissima means "longest" inLatin, referring to the unusual size of the nectar spurs.
Aquilegia longissima is native toTrans-PecosTexas and southernArizona in theUnited States andChihuahua,Coahuila,Nuevo León, andSonora in northern Mexico.[8] It grows at altitudes of 1,370–1,520 m (4,490–4,990 ft)[3] in gravellylimestone or igneous soils, on canyon walls, and along streams, drainages, springs, or waterfalls, within shady, mesic canyons of pine-oak or pine-oak-juniper woodlands.[1]
Aquilegia longissima flowers from July to September.[3]
William Trelease hypothesized in 1883 that the most likely pollinator ofA. longissima would be the giant sphinx moth,Cocytius antaeus.[9] The giant sphinx moth is a rare stray in west Texas and has been collected inBig Bend National Park near long-spur columbine populations; however, the common pollinators are likely large hawkmoths in the generaManduca andAgrius with tongue lengths from 9–14 cm (3.5–5.5 in) long.
Hybridization is common among columbines and populations with intermediate spur lengths from 7–9 cm (2.8–3.5 in) are found near some long-spur columbine populations.[10] One such population is found at Cattail Falls in Big Bend National Park, a site significantly impacted by human visitation.[1]
As of November 2024[update],NatureServe listedAquilegia longissima asVulnerable (G3) worldwide. This status was last reviewed on19 November 1997. In individual states, it is listed as Imperiled (S2) in Texas and has no status rank in Arizona.[1] It has not been assessed for theIUCN Red List.[11]
