Pithecellobium cynodonticum

  • Title

    Pithecellobium cynodonticum

  • Author(s)

    Rupert C. Barneby

  • Scientific Name

    Pithecellobium cynodonticum Barneby & J.W.Grimes

  • Description

    5. Pithecellobium cynodonticum  Barneby & Grimes, sp. nov., P. circinali (Linnaeus) Bentham arete affi- nis, imprimis foliis abbreviatis, pinnarum rachi 1-5 (nec 6-34) mm usque longa nectario apicali desti- tuta, foliolis majoribus 2-5 (nec 6-34) mm tantum longis, ulterius ramis primariis confertissime foli- atis foliolisque nunc muticis nunc breviter (nec omnibus longe) mucronatis diversa; habitu, foliolis parvis, nectario pinnarum deficiente P. histricem (A. Richard) Bentham revocans, sed ab ea foliolorum numero (cujusque folii 4—8, nec exacte 4) necnon corolla puberula breviori ±4.5 (nec 6-10) mm longa distantior. — HAITI. Nord-Ouest: Presqu’Ile Nord-Ouest, 7 km al oeste de Anse Rouge en la carretera costera a Baie de Henne, 19°38'N, 73°56'W, alt. 40 m, 10 Jun 1985 (fr., few buds and faded fls.), T. Zanoni (with M. Mejia & R. Garcia) 35073. — Holotypus, JBSD 69564; isotypi, NY (2 sheets)!.                                                                                                                       Fig. 2

    Stiffly virgately few-branched, densely microphyllous shrubs 1.5-2 m, armed at all nodes with a pair of widely ascending or subhorizontal, lignescent stipules, the young growth densely puberulent throughout with erect pallid hairs to 0.1-0.15 mm, the primary lvs early shed and replaced at each node by a fascicle of 2-3 very small lvs and an occasional peduncle, the small firm plane lfts bicolored, fuscous above, tan beneath. Stipules of primary lvs tapering from dilated base, 3-7 mm, those of brachyblasts subulate, <1 mm. Lf-formula i/1-2, of all primary and of many brachyblastic lvs i/2, the lfts then 8 per lf; lf-stks 1-2 mm, charged at apex with a subsessile pored nectary 0.3-0.4 mm diam; pinna-rachises 1—4.5(—5) mm, lacking nectary, the one interfoliolar segment (when present) 1-2.5 mm; lfts obliquely obovate from postically rounded, antically cuneate base, either broadly obtuse and muticous or (on same branchlet) abruptly produced into a spinulose mucro 0.2-0.5 mm, the blades of distal or only pair 2.5-6 x 2-4 mm, 1.2-2.5 times as long as wide; venation pinnate, the subcentric, straight or gently incurved midrib giving rise on each side to 3-5 weakly brochi-dodrome, simple or almost simple secondary nerves, nervation bluntly prominulous beneath, less so above. Peduncles (few seen) solitary ±5-8 mm; capitula 25-30(-?)-fld, the globose or clavate receptacle ±2 mm; bracts linear-lanceolate 0.7-1 mm, persistent; fls (seen only in advanced bud and faded) sessile, homomorphic, the perianth puberulent overall; calyx campanulate 5-nerved ±1.5 mm; corolla 4.5 mm. Pod, seeds, and red aril of P. circinale.

    On dry limestone of almost dog’s-tooth type, in arid matorral at ±40 m, known only from the type locality on the S shore of Presqu’Ile Nord-Ouest, Haiti. — Not mapped. — Fl. season uncertain (random fls in IV).

    Pithecellobium cynodonticum resembles P. histrix in diminutive leaves crowded along stiffly branched stems with intemodes shorter than stipules (Fig. 1, no. 0), and in loss of nectary at tip of each pinna, but differs in having two pairs of leaflets in the more vigorous 5 mm. pinnae and, so far as known from one collection, smaller, puberulent flowers. Geographically, it is remote from P. histrix but sympatric with P. circinale. It has the leaf-formula of P. circinale and the excurrent (but shorter) mucro of the leaflets, but has much smaller leaflets (to 2-5 mm long) and stiffer, very densely foliate stems that contribute to a distinct facies. The epithet (from Gr. kyon, dog + odons, tooth) alludes to the habitat on dog’s-tooth limestone.