Geonoma maxima subsp. chelidonura (Spruce) Henderson, 2011

Henderson, Andrew, 2011, A revision of Geonoma (Arecaceae), Phytotaxa 17, pp. 1-271 : 99-100

37d. Geonoma maxima subsp. chelidonura (Spruce) Henderson , comb. & stat. nov.

Basionym: Geonoma chelidonura Spruce (1871: 111) . Geonoma maxima var. chelidonura (Spruce) Henderson (1995: 279) . Type: BRAZIL. Amazonas: Rio Uaupés, November 1852, R. Spruce 73 (holotype K!).

Geonoma tuberculata Spruce (1871: 112) . Geonoma spruceana subsp. intermedia var. tuberculata Trail (1876: 329) . Type: BRAZIL. Amazonas: Rio Negro, no date, R. Spruce 18 (holotype K!).

Geonoma densiflora Spruce (1871: 112) . Type: BRAZIL. Amazonas: São Gabriel, near Gama’s sitio, March 1852, R. Spruce 30 (holotype K!).

Geonoma personata Spruce (1871: 112) . Type: BRAZIL. Amazonas: Serra of São Gabriel, June 1852, R. Spruce 34 (holotype K!).

Geonoma densiflora var. monticola Spruce (1871: 118) . Type: BRAZIL. Amazonas: São Gabriel, June 1852, R. Spruce 33 (holotype K!).

Geonoma spruceana Trail (1876: 328) . Type: BRAZIL. Pará: Lago Juruty, 3 April 1874, J. Trail 1002/XXIV (holotype K!, isotype BM!).

Geonoma spruceana subsp. spruceana var. heptasticha Trail (1876: 329) . Type: BRAZIL. Amazonas: Rio Negro at Assutuba, 6 July 1874, J. Trail 1007/XCIII (holotype K!, isotype BM!).

Geonoma spruceana subsp. intermedia var. m ajor Trail (1876: 330). Type: BRAZIL. Amazonas: Rio Solimões, Coary, 16 October 1874, J. Trail 984/CXLIV (holotype K! isotypes BM!, NY!).

Geonoma juruana Dammer (1907: 119) . Type: BRAZIL. Acre: Rio Juruá, Juruá-mirim, August 1901, E. Ule 5744 (holotype B, destroyed, isotypes F!, MG!).

Geonoma longisecta Burret (1930a: 257) . Type: PERU. Loreto: Iquitos, 4 May 1925, G. Tessmann 5087 (holotype B, destroyed, isotype, NY!).

Geonoma parvisecta Burret (1930b: 1018) . Type: BRAZIL. Amazonas: Rio Negro, São Pedro do Uaupés, 23 September 1928, P. Luetzelburg 22278 (holotype B, destroyed, isotypes M!, NY!).

Leaves undivided or irregularly pinnate (sometimes with 1-veined pinnae present), not plicate; rachis 24.7(7.3–63.0) cm long; pinnae 3(1–10) per side of rachis; basal pinna 4.3(0.2–20.0) cm wide, forming an angle of 44(10–87)° with the rachis. Inflorescences rachillae 15(4–36).

Distribution and habitat:— From 2°03’N– 11°45’S and 55°00’– 75°50’W in the central–western Amazon region of Venezuela, Colombia, Brazil, Peru, and Bolivia at 160(48–525) m elevation in lowland rainforest ( Fig. 25 ).

This is the most variable subspecies with several local morphotypes.

Some specimens (large fruit morphotype) in the western part of the range in Peru and Colombia, especially from around Iquitos in Peru, have larger fruits (mean fruit length 14.0 mm, mean fruit diameter 11.0 mm) than those of other specimens (mean fruit length 11.0 mm, mean fruit diameter 8.2 mm).

Specimens ( parvisecta morphotype) from scattered areas in Colombia, Venezuela, Peru, and Brazil, especially in the upper Rio Negro region, often in black water river areas on sandy soils (campina, catinga), are smaller than others and often have undivided leaves. The types of Geonoma chelidonura and G. parvisecta are of this morphotype.

Most specimens (e.g., Henderson 1517, Trail 989, 991, 998, 1002, 1005, 1007)(intermediate morphotype) from the eastern part of the range in Brazil, occurring in flooded areas near the main Amazon river (várzea), have 1-veined pinnae interspersed between the wider basal and apical pinnae, and in some cases resemble the sympatric subsp. compta .

A few specimens from widely scattered localities (Balick 942, Gruezmacher 45, Kuhlmann 1237, Le Fiell 4, Moore 8428, Pipoly 15638, Prance 7596, Rimachi 10965, 11275, Rudas 3101)( densiflora morphotype) in Peru, Colombia, Venezuela, and Brazil (including an unmapped specimen, Kuhlmann 1237, from “ Tocantins ”, Pará) have thinner textured, sigmoid pinnae, few, thicker rachillae, and persistent pistillate flowers. The types of G. densiflora , G. densiflora var. m onticola, and G. personata have these kinds of leaves and inflorescences. The specimens often occur sympatrically with subsp. chelidonura and subsp. compta and may be of hybrid origin.

Figures

FIGURE 25. Distribution maps of Geonoma maxima subsp. maxima, G. maxima subsp. ambigua, G. maxima subsp. camptoneura, and G. maxima subsp. chelidonura.