276 Phytologia (August2012) 94(2) SENEGALIAARISTEGUIETANA CARDENAS) SEIGLER & (L. EBINGER (FABACEAE: MIMOSOIDEAE): AN UNCOMMON SPECIES OF CENTRAL AMERICA AND NORTHERN SOUTH AMERICA David S. Seigler* Department ofPlant Biology, University ofIllinois, Urbana, IL 61801 *Correspondent: [email protected] and John E. Ebinger Emeritus ProfessorofBotany, Eastern Illinois University Charleston, IL 61920 ABSTRACT A new combination is made in Senegalia: Senegalia aristeguietana (L. Cardenas) Seigler & Ebinger, based on Acacia aristeguietana L. Cardenas, Emstia 2(1-2):31. 1992. We have collections from southern Mexico (Chiapas), Honduras, Panama, Colombia and Venezuela. A detailed description ofthe taxon is given. Phytologia 94(2): 276-279 (August 1, 2012). KEY WORDS: Senegalia aristeguietana comb, nov., Fabaceae. During our studies ofAcacia s. 1. in the New World, we found a few specimens thatwe originally thought representeda new species in the genus Senegalia. Recently we discovered that this entity had already been described by Cardenas (1992) as a member ofthe genus Acacia from a single state in Venezuela. The name proposed by Cardenas (1992), Acacia aristeguietana fits, in all distinguishing characteristics, the specimens that we had originally considered to represent a new species. Unfortunately, when we examined the Kew isotype ofthis species, we erroneously synonymized it with Senegalia polyphylla (DC.) Britton & Rose (Seigler et al. 2006). The new combination is made below along with a detailed species description, specimens examined, and discussion ofthe probable relationship ofthis taxon to closely related species.