Ranunculus lambayequensis T.Duncan & Sagást.
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Authority
Thomas, Duncan & Sagástegui Alva, Abundio. 1990. A New Species of Ranunculus (Ranunculaceae) from Peru. Brittonia. 42 (3): 182-184.
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Family
Ranunculaceae
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Scientific Name
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Description
Latin Diagnosis - Herba perennis; radices succulentae, 3-5 mm diametro; caules aeriales erecti, 10-20 cm longi, 2-3 mm diametro; folia basalia plerumque ovata, non profunde vel profunde terni-lobata, saepe lobo terminali tridentato praedita, marginibus pilis rigidis curvis ciliata, utrinque pilis sparsis appressis praedita; flores in scapo 10-20 cm longo solitarii, pilis aureis sericei; sepala 5, appressa, lanceolata, 8-12 mm longa, 3.5-5 mm lata, 2/3-7/8 longitudinis petalorum; petala 7-10, lutea, oblanceolata, 10-14 mm longa, 4-6 mm lata, apice emarginata; squama nectarialis sacculum semi-circularem formans; achaenia 1.8-2.5 mm longa, 1.3-1.6 mm lata, inflata, in rostrum tenue 0.5-1 mm longum contracta; receptaculum conicum.
Species Description - Perennial herb; roots fleshy 3-5 mm diam; aerial stems erect, 10-20 cm long, 2-3 mm diam; basal leaves ovate overall, shallowly to deeply temately lobed, often with the terminal lobe tridentate, margins ciliate with stiff curved hairs, upper and lower surfaces with scattered appressed hairs; flowers solitary on scapes 10-20 cm long, these sericeous, with golden hairs; sepals 5 spreading, lanceolate, 8-12 mm long, 3.5-5 mm wide, 2/3-7/8 as long as the petals; petals 7-10, yellow, oblanceolate, 10-14 mm long, 4-6 mm wide, apex emarginate; nectary scale forming a semi-circular pocket; achenes 1.8-2.5 mm long, 1.3-1.6 mm wide, inflated, tapering into a slender beak 0.5-1 mm long; receptacle conical.
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Discussion
TYPE: PERU. Dpro. LAMBAYEQUE: Prov. Ferreniafe, Laguna Tembladera, Cerro Negro, 3300 m, 12 Sep 1985, Sagdstegui-A., D. Skillman, J. Mostacero, & L. Ramirez 12826 (HOLOTYPE: F; ISOTYPES: HUT, UC).
Etymology: This species is named for the Departamento de Lambayeque.
Ecology: Ranunculus lambayequensis occurs in the jalca above the town of Incahuasi (6º15'S, 79º20'W) near the border of Departamento de Lambayeque and the Departamento de Cajamarca. Plants were noted in very moist places near the shore of the Laguna Tembladera. Associates in this habitat are Loricaria ferruginea Wedd., Carex sp., Juncus sp., Gentianella sp., and Valeriana rigida Ruiz and Pavon.
Relationships: This single collection of Ranunculus, containing both flowers and fruits, is sufficient to offer a preliminary outline of the relationships of this species to other members of Ranunculus. From a comparison with other Western Hemisphere species of Ranunculus, this species appears to be a member of the section Epirotes (Prantl) L. Benson. The pocket-like nectary scale and the smooth and turgid achenes (Fig. 1) are the basis for this placement. A related species appears to be R. donianus Pritzel, native to high mountains of central and western Mexico and Sierra de los Cuchumatanes in Guatemala (Benson, 1948). Plants of R. donianus have scapes less than 5 cm long and small flowers with petals about 3 mm long and with sepals of approximately the same length. The overall size of R. lambayequensis is much larger than R. donianus. In addition, R. lambaye- quensis has deeply lobed leaves, more turgid achenes, and a more elongate receptacle. Of South American species, R. lambayequensis may be related to Ranunculus bangii Lourteig, a species known from only one collection from La Paz, Bolivia (Lourteig, 1956). Ranunculus lambayequensis is distinguished from R. bangii by its long sepals and erect habit. In R. bangii, the sepals are approximately one-half the length of the petals and the plant is stoloniferous. The very small amount of material of these species shows that more study of high Andean Ra- nunculaceae is much needed.
In the Flora of Peru (Macbride, 1937), R. lambayequensis would key to R. sibbaldioides. As discussed in Duncan (1980), R. sibbaldioides is synonymous with R. praemorsus var. praemorsus, a widespread species found throughout the An- dean region. R. praemorsus var. praemorsus differs from R. lambayquensis in its dome-shaped receptacle, reflexed sepals, and longer achene beaks. The other species at this lead, R. breviscapus, is a species with three sepals and a strongly stolonifer- ous habit distributed from central Peru to northern Bolivia. This species is treated more fully in Lourteig (1956).
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Distribution
Known only from the jalca in Lambayeque. This area of Peru had been largely unexplored prior to the collecting efforts of Sagastegui-A. and his colleagues. New species have been described from this material including Gynoxys dilloniana Sagast. & Tellez and Symplocos incahuasensis Sagast. & Dillon. Further collecting in this area is needed to document more fully the distribution of this and other new species.
Peru South America|