Sphinga acatlensis

Title

Sphinga acatlensis

Author(s)

Rupert C. Barneby

Scientific Name

Sphinga acatlensis (Benth.) Barneby & J.W.Grimes

Description

2. Sphinga acatlensis (Bentham) Barneby & Grimes, comb. nov. Pithecolobium acatlense Bentham, Trans. Linn. Soc. London 30: 593, 1875. — "Mexico, Acatlan, in the Pueblo district [estado de Puebla], Andrieux, n. 395." — Holotypus, K!; isotypus, P!. — Feuilleea acatlensis (Bentham) O. Kuntze, Revis. Gen. Pl. 1: 187. 1891. Havardia acatlensis (Bentham) Britton & Rose, N. Amer. Fl. 23: 42. 1928.

Pithecolobium acatlense sensu Rose, Contr. U.S. Natl. Herb. 5: 195. 1899; M. Micheli, Mém. Soc. Phys. Geneve 34: 284, t. 27. 1903 (= Langlassé 1031, GH! sub nom. ined. Calliandra eriopetala M. Micheli); Standley, 1922: 395; McVaugh, 1987: 233.

Xeromorphic, drought-deciduous, microphyllous shrubs and trees 2-7 m with stout stiff virgate, fuscous pallid-lenticellate, early glabrate branches armed at each node of long-shoots with a pair of ascending, straight or commonly gently recurved, glabrous atropurpureous spinescent stipules, the axes of new lvs softly pilosulous with fine spreading white hairs to 0.3-0.5 mm, the pallidly olivaceous, scarcely bicolored, firm-textured lfts glabrous or facially glabrous but remotely ciliolate to thinly pilosulous on both faces, the few-fld capitula of long, densely pilosulous whitish fls arising singly from short-shoots either coevally with or well before a fascicle of hornotinous lvs, the long, densely tomentulose pods pendulous. Stipules of primary lvs on long-shoots 3.5-9 mm, at base ±1-1.5 mm diam and obscurely trigonous, tapering and vulnerant distally, long-persistent after fall of associated lf, the stipules of fasciculate lvs much shorter and more slender. Lf-formula ii-v/7-14(-"16"); lf-stks slender, those of major lvs (1-) 1.5-4 cm, (of random fasciculate or drought- inhibited lvs, no further described, shorter), the petiole (5-)6-26 mm, at middle 0.35-0.6 mm diam, the longer interpinnal segments (1.5—)2.5—8 mm, the narrow ventral groove continuous; nectary near or well below midpetiole sessile, shallowly cupular, round or elliptic 0.4-1.6 mm diam, thick-rimmed, in profile not over 0.3 mm tall, no nectaries on upper lf-stk, rare minute ones at tip of some pinna-rachises; pinnae little graduated in length, the rachis of longer ones (6-)9-36 mm, the longer interfoliolar segments (0.9-) 1.2-3 mm; lft-pulvinules 0.3-0.5 x 0.25-0.3 mm; lfts a little decrescent at each end of rachis, elsewhere subequilong, narrowly ovate or lance-oblong from asymmetrically shallow-cordate or semicordate base, contracted into a sharply acuminulate tip 0.3-0.5 mm, a little forwardly curved, those near mid rachis (3.7-)4-9.5 x 1.4—3.4 mm, 2.4-3.6(-4.1) times as long as wide; venation of 2-3 nerves from pulvinule, the gently incurved midrib displaced to divide blade ±1.2-2 and giving rise on posterior side to (2-)3-4 secondary nerves brochidodrome close within the plane margin, the one (or inner) posterior nerve produced to anastomosis well short of midblade, the outermost when present much shorter, the whole venation immersed on upper face, bluntly, sometimes faintly prominulous beneath. Peduncles 1-8 mm, rigid and woody in fruit; capitula (3-)4-8- fld, the fls ascending homomorphic, the receptacle scarcely dilated 1-1.5 mm; bracts 2-4 mm, either linear, or oblanceolate, or narrowly ovate, becoming papery and deciduous at anthesis; perianth basically 5-merous, but corolla-lobes often fused and the sinuses between calyx-teeth often very unequal, the calyx yellowish striate, thinly pilosulous, the corolla densely white-silky-pilose; calyx in early bud narrowly flask-shaped acute or acuminate, at anthesis cylindro-campanulate 9.5-12.5 x 3-4.5 mm, contracted at base into a drum-shaped stipe not over 1 mm, the lanceolate acute teeth to 3-4.5 mm; corolla 14.5-18.5 mm, the hooded lobes separated by sinuses ±1-6 mm deep, some united to tip; androecium (86-)140-176-merous, (43-)48-57 mm, the ste- monozone 1.5-2.5 mm, the tube 10-19 x 1.8-3 mm, ±1 mm shorter to 3.5 mm longer than corolla; disc (0.6-)0.8-l .3 mm, sometimes charged internally with a few weak hairs; ovary shortly stipitate, at anthesis glabrous, tapering at each end, shallowly sulcate laterally; stigma a little dilated, ±0.2-0.25 mm diam. Pods 1 per capitulum, technically sessile but attenuate at base into a laterally grooved pseudostipe 5-20 mm, in profile broad-linear straight (10-) 12-18 x 1.8- 2.4(-2.9) cm, (7-)8-10-seeded, abruptly contracted at apex into a fragile (often broken) erect cusp 3.5- 9(—15) mm, the piano-compressed, stiffly papery or leathery valves framed by obtusely 3-ribbed sutures ±3-4 mm wide, low-convex over each seed, densely gray- or brownish-pilosulous overall, internally pallid dull, the cavity continuous; seeds transverse, basifixed on dilate sigmoid funicle, plumply discoid, in broad view round or bluntly oblong, 9-13 x 8.5-12 x 2-2.5 mm, the leathery or crustaceous, castaneous and highly lustrous testa 0.2-0.3 mm thick in section, closely investing the embryo, a little thickened at the periphery, the pleurogram irregularly U-shaped ±5-8 x 3.5-6.5 mm.

On open hillsides and plains in mesquite-grass- land, matorral and thorn-scrub, or tropical deciduous woodland, 500-1650 m, scattered in Mexico from the S lobe of Durango and W Jalisco E through the Balsas basin to the Tehuacán desert and headwaters of Río Papaloapan in Puebla. — Map 43. — Fl. Ill—VII, with or preceding new foliage. — Asinchete, cinchete (México, Guerrero).