Plukenetia carabiasiae, J. Jimenez Ram., Anales Inst. Biol. Univ. Nac. Auton.

18. PLUKENETIA CARABIASIAE J.Jiménez Ram., Anales Inst. Biol. Univ. Nac. Autón. View in CoL México, Bot. 64 (2): 55. 1993. TYPE: MEXICO. Oaxaca: Distrito Tuxtepec , Municipio San Felipe Usila , Cerretera de Arroyo Tambor a Cerro Verde, [17.833°, -96.467°], 500 m, 9 April 1992, J. Ismael Calzada 17733 (holotype: FCME; isotype: MEXU) .

Notes —See Jiménez Ram´ırez (1993) for species description. This species was described after Gillespie (1993) and is known only from a few collections from the Tuxtepec district of Oaxaca, Mexico (J. Ismael Calzada 16965 FCME, 17733 FCME, MEXU; Meave et al. 1550 MO! [accession 04786568, barcode MO-1147591], MO! [accession 6030707, barcode MO-2056000]). It appears to be morphologically similar to P. polyadenia but with smaller, at least semi-dehiscent fruit, “large” to “extra-large” broadly lenticular seeds, and longer styles. The staminate floral morphology of P. carabiasiae is not yet known.

19. PLUKENETIA CAROLIS-VEGAE Bussmann, Paniagua & C.Téllez, Econ. Bot. View in CoL 67 (4): 388. 2013. TYPE: PERU. Amazonas : Provincia de Rodr´ıguez de Mendoza, Distrito de Limabamba, finca of Sr. Rodr´ ıguez in Monte Alegre, [-6.58547°, -77.53214°], 1854 m, 19 August 2012, R.W. Bussmann, N. Paniagua Zambrana, C. Vega Ocana ~ & R. Arista Melendez 17132 (holotype: HAO (not seen); isotypes: MO [sheet 1 of 2; accession 6605775, barcode MO-2822725 ; image!], MO [sheet 2 of 2; accession 6605774, barcode MO-2822724 ; image!]; INBIAPERU [Instituto para el Desarrollo Local Sostenible y la Conservación Biológica y Cultural Andino-Amazónica, Trujillo]). [The two isotype sheets at MO could not be found at the time of writing. They are mistakenly labeled as holotypes according to images on Tropicos.org.]

Discussion —Together, P. carolis-vegae , P. 3 huayllabambana , and our proposed new species P. sylvestris , form a high elevation species complex sister to P. volubilis . Members of the species complex grow in high elevation montane rainforest in the Andes, 1280–2440 m, and possess staminate flowers with large irregularly shaped interstaminal nectary segments, short styles partly connate into a squarish-cylindrical column usually, 10 mm long, fruits; 3–10 cm in diam with “large” or “extra-large” seeds, and 1–2 thick stipels at their petiole apex.

The two previously described species, P. carolis-vegae and P. 3 huayllabambana , are geographically and morphologically similar to each other. Both taxa are primarily distributed in the Rodr´ıguez de Mendoza Province in northern Peru ( Fig. 6 View FIG ), have large fruits 4–10 cm in diam with “extra-large” seeds, and appear to be fully or semi-domesticated with possible cultivation or reintroduction into forests adjacent to farmland. Plukenetia carolis-vegae differs by having 25–35 stamens with longer filaments, 0.5–1 mm long (perhaps as long as; 1.8 mm, see below), 4 (rarely 5) staminate sepals, and inflorescences densely packed with staminate cymules. By comparison, P. 3 huayllabambana has 10–15 stamens with shorter filaments, 0.1–0.3 mm long in its type description ( Bussmann et al. 2009) but; 0.5 mm long in an independently measured specimen (Quipuscoa 381 MO), 5 (rarely 4) staminate sepals, and inflorescences loosely packed with staminate cymules.

We hypothesize that P. carolis-vegae is a cultivated species derived from natural populations of our new species P. sylvestris . Presently, P. carolis-vegae is only known from its type collection (Bussmann et al. 17132), which was collected from a farmer’ s field ( Bussmann et al. 2013). It is most clearly distinguished from P. sylvestris by its larger fruits and seeds but otherwise they appear to share the densely packed inflorescences and longer filaments that distinguish both species from P. 3 huayllabambana (based only on illustrations and photographs from Bussmann et al. 2013; no specimens were available for examination). Based on its description, P. carolis-vegae also differs by having 25–35 stamens and 4 (rarely 5) staminate sepals, compared to 10–18 stamens and regularly 4–5 staminate sepals in P. sylvestris .

Unfortunately, the MO isotype sheets of P. carolis-vegae could not be located at the time of writing, but are needed to conduct better morphological comparisons with P. sylvestris and to review discrepancies with its species description. For instance, the description of P. carolis-vegae characterized its filaments as relatively short, 0.5–1 mm long, and its staminate flowers as lacking nectaries, but the type illustration ( Bussmann et al. 2013, Fig. 1C View FIG ) suggests its filaments can be as long as; 1.8 mm and that large irregularly shaped nectary segments are present. Additionally, its stamens were reported as “25–35 3 0.1–0.3 mm in diameter,” which by convention implies a length of 2.5–3.5 cm, surpassing any stamen length observed in Plukenetia . However, Bussmann et al. (2013) also specify that the filaments are 0.5–1 mm long, suggesting there was a typographical error and that 25–35 refers to stamen number and not length. Indeed, the species description of P. 3 huayllabambana ( Bussmann et al. 2009) uses a similar, although less conventional, format (“stamens 10–14, 0.2–0.4 mm in diameter; filaments flattened, broad, 0.1–0.3 mm long”), which suggests the authors intended to report 25–35 stamens.

Distribution, Habitat, and Phenology —Presently, this species is only known from its type collection from the Amazonas region of northern Peru ( Fig. 6 View FIG ). It is a twining liana 4–6 m long, found in cultivation at 1855 m elevation. The type collection contains both flowers and fruits and was collected in August.

20. PLUKENETIA 3 HUAYLLABAMBANA Bussmann, C.Téllez & A.Glenn, Nordic J. Bot. View in CoL 27 (4): 313. 2009. TYPE: PERU. Región Amazonas: Provincia de Rodr´ıguez de Mendoza, El Cedro-Cruzpata, [-6.404°, -77.449°], 1676 m, 5 July 2008, C. Téllez, C. Vega & L. Cabrera 02 (holotype: INBIAPERU [Instituto para el Desarrollo Local Sostenible y la Conservación Biológica y Cultural Andino-Amazónica, Trujillo]; isotype: K [barcode K001089689; image!]). [The isotype was originally published as housed at MO ( Bussmann et al. 2009), but only one sheet of a different collection (Téllez et al. 004, MO! [accession 6116702, barcode MO-2255093]) incorrectly labeled as an isotype could be found. The isotype has since resurfaced at Kew (Téllez et al. 02, K [barcode K001089689; image!]) and it appears to be the isotype that was originally deposited at MO (“Ex Herbarium” MO [accession 6116701]).]

Discussion — Plukenetia 3 huayllabambana , along with P. carolis-vegae and P. sylvestris , form a high elevation species complex sister to P. volubilis . Members of the species complex grow in high elevation montane rainforest in the Andes, 1280–2440 m, and possess staminate flowers with large irregularly shaped interstaminal nectary segments, short styles partly connate into a cylindrical column usually, 10 mm long, and 1–2 thick stipels at their petiole apex. Members of the species complex also have larger fruits and seeds, fruits 4–10 cm in diam with “extra-large” seeds in P. 3 huayllabambana and P. carolis-vegae , and fruits 2.8–3.7 cm in diam with “large” seeds in P. sylvestris (similar in size to P. volubilis but with larger seed volume; Cardinal-McTeague et al. 2019a).

This species is a putative hybrid between P. sylvestris 3 P. volubilis, which is supported by the presence of a P. volubilis plastid genome in accessions of P. 3 huayllabambana ( Cardinal-McTeague et al. 2019a, Fig. S3 View FIG ) and their intermediate staminate floral morphology. Both P. 3 huayllabambana and P. volubilis have stamens with short filaments,; 0.5 mm long, compared to longer filaments,; 0.5–1.4 mm long, in P. sylvestris . Staminate sepal number also appears to differ, more frequently with 5 (rarely 4) sepals in P. 3 huayllabambana and, regularly varying from 4–5 sepals in P. sylvestris , and with 4 sepals in P. volubilis .

Plukenetia View in CoL 3 huayllabambana View in CoL is distributed in the Amazonas and Cajamarca Regions of northern Peru ( Fig. 6 View FIG ). It is known from only a few collections across three districts but is possibly more common in cultivation. Its staminate flowers were originally described as having filaments 0.1–0.3 mm long and [nectary] disc absent ( Bussmann et al. 2009), but our observations found filaments; 0.5 mm long and large irregularly shaped interstaminal nectary segments to be present (Quipuscoa 381 MO). The original type illustration shows an immature staminate flower dissected from a bud, whereas the staminate flower at anthesis is aberrant and likely from a non-euphorb species ( Bussmann et al. 2009, Figs. 1J and 1H View FIG , respectively).

Specimens Examined — Peru. — AMAZONAS: Chachapoyas District, Distrito Leymebamba [sic], Los Chichos / San Lucas , [-6.701°, -77.586°], 2150 m, 19 June 2000, Gruhn et al. 84 ( MO [accession 6406258, barcode MO-2695407 ; seeds: accession 5451714, barcode MO-2695406 ]) ; Rodriguez de Mendoza District, Michina , [-6.378°, -77.527°], 1608 m, 5 June 2008, Téllez et al. 004 ( MO [accession 6116702, barcode MO-2255093 ]) ; Rodriguez de Mendoza District, Quebrada Seca , [-6.378°, -77.527°], 1608 m, 5 June 2008, Téllez et al. 006 ( NY [barcode 02200737; image]) . — CAJAMARCA: San Ignacio, Distrito San José de Lourdes, Villarrica , Nororiental del Maranón ~ RENOM,[-4.917°, -78.833°], 1200–1420 m, 28 October 1995, Quipuscoa 381 ( MO [5294603, barcode MO-302027 ]) .