Neotropical Lacistemataceae

Mac H. Alford

University of Southern Mississippi (USMS), USA. 

Description

Shrubs or small trees. Leaves alternate, simple, stipulate, blades pinnately veined, margins entire to (less commonly) denticulate or serrate. Inflorescences axillary catkin -like cylindrical spikes or spiciform racemes. Flowers minute, bisexual (or less commonly andromonoecious or monoecious), each flower subtended by a bract or bracts, which are sometimes partially fused and cup-like. Sepals 1-6. Petals lacking. Disk present, variously shaped but sometimes annular or cup-shaped and misinterpreted as other structure. Stamen 1, attached to the inner surface of the disk, connective between the anthers often expanded or anthers stipitate, anther dehiscence introrse. Gynoecium of one pistil, ovary superior, unilocular, placentation parietal, style short or long, stigmas (2-)3. Fruit berry-like but eventually dehiscent by three loculicidal valves. Seed(s) 1(-3), arillate.

Notes on delimitation

  • Lacistemataceae have traditionally been allied with or sometimes placed in Flacourtiaceae.
  • Phylogenetic analyses based on DNA sequence data have indicated that Flacourtiaceae are polyphyletic and that Lacistemataceae are related to one group of the former Flacourtiaceae now placed in Salicaceae sensu lato (Malpighiales).

Distribution in the Neotropics

  • Lacistema Sw.:  Mexico to SE Brazil, Paraguay, Uruguay, and NE Argentina.
  • Lozania Mutis ex Caldas:  Costa Rica to Peru and Brazil.

Distinguishing characters (always present)

Other important characters

  • Anthers usually with an expanded connective, that is, anther thecae stipitate.
  • Seeds arillate.

Key differences from similar families

  • If reproductive parts are available, the family is usually diagnosable by the presence of catkin-like spikes or spiciform racemes and flowers with a single stamen.

Number of genera

  • Lacistema (11 spp.)
  • Lozania (3 spp.)

Useful tips for generic identification

Key to genera of Neotropical Lacistemataceae

1. Inflorescences catkin -like spikes .... Lacistema
1. Inflorescences slender spiciform-racemes (or -panicles) .... Lozania

Status

  • Endemic.

General notes

  • Lacistema aggregatum Rusby is a fairly common and widespread species in the Neotropics.

Important literature

Chase, M. W., S. Zmarzty, M. D. Lledó, K. J. Wurdack, S. M. Swensen, & M. F. Fay. 2002. When in doubt, put it in Flacourtiaceae: a molecular phylogenetic analysis based on plastid rbcL DNA sequences. Kew Bulletin 57: 141-181.

Chirtoiü, M. 1918. Observations sur les Lacistema et la situation systématique de ce genre. Bull. Soc. Bot. Genève, sér. 2, 10: 317-349.

Sleumer, H. O. 1980. Flacourtiaceae. Flora Neotropica No. 22. Bronx: New York Botanical Garden. Pp. 182-206. [Two illustrations. All species treated.]

How to cite

Alford, M.H. (2009). Neotropical Lacistemataceae. In: Milliken, W., Klitgård, B. & Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics. http://www.kew.org/science/tropamerica/neotropikey/families/Lacistemataceae.htm.