Key to Species of the Taxus Wallichiana Group

IA. Subgroup Wallichiana

©The World Botanical Associates Web Page
Prepared by Richard W. Spjut
April 2003

1. Stomata 12 or more rows per band; E Himalayas, SW China.......—2

1. Stomata less than 12 rows per band…... ........…..….….…….….—3


2. Persistent bud-scales relatively large, 2–3 mm
    long, nearly plane with distinct mid-nerve (Fig. 20);
    Myanmar........................................................—4. Taxus suffnessii

2. Persistent bud-scales nerveless, or nearly so, concave,
less than 2 mm long and 1 mm wide (Fig. 21–23), if scales
not evident or leaves obtuse see Chinensis Subgroup; E
Himalayas, Nepal to SW China).....…..—5. Taxus wallichiana—2a

Fig. 21–23: Taxus wallichiana var. wallichiana from Nepal, Wallich 6054A (K). Fig. 21 (left): note contrast between yellowish orange branchlets and older dark maroon branch, and seed. Fig. 22 (isosyntype): from a male plant showing loosely adherent, tooth-like scales. Fig. 23 (right): from Khasia, India Hooker & Thomson 77 ex Herb. Bunge (P), showing close-up of persistent bud-scales.

Fig. 24–25, scanned from author's sketches on 3x5 inch packet envelopes of microscopic leaf sections of Taxus wallichiana showing T-sect. of leaf near margin and as seen on abaxial epidermal surface (~ 250Χ).  Fig. 24 (left): var. yunnanensis, from Zayul, Tibet (topotype), Kingdon Ward 10398 (BM ). Fig. 25 (right):  var. wallichiana, Griffith 2606 from Assam, India (BM).

2a. Leaves nearly lanceolate (Fig. 26), the undersurface with epidermal cells in
  T-sect. of marginal region slightly smaller below (abaxial surface) than above
  (adaxial urface), generally 35–50 ΅m wide; papillae mostly in opposite rows
  on midrib and marginal cells (Fig. 24); Nepal, NE India, Myanmar, Tibet,
  Yunnan.........................................................................—5b. Taxus wallichiana var. yunnanensis

2a. Leaves linear (Fig. 27), the undersurface with epidermal cells in T-sect. of
 marginal region much smaller than those above (adaxial), generally 15–25 ΅m
 wide; papillae mostly in alternate rows on midrib and marginal cells, or confined
 to cell walls (Fig. 25); NE India, Nepal, Bhutan, Myanmar, Tibet, Sichuan,
 Hubei.................................................................…………—5c Taxus wallichiana var. wallichiana

Fig.26 (left). Taxus wallichiana var. yunnanensis, Wang 67412 from Yunnan, China (A), showing lanceolate type of leaf.  Fig. 27 (right). Taxus wallichiana var. wallichiana, Griffith 5002 from “East Himalaya” (P), showing linear type of leaf.

3. Abaxial leaf epidermal cells gradually narrower and shorter from stomata band
to margin, mostly isodiametric in T-sect., generally 3–10Χ l/w, fusiform and
incrassate (wavy along cell walls) on abaxial surface, or rarely rectangular.................................Taxus globosa —4

3. Abaxial leaf epidermal cells abruptly shorter and wider in marginal region,
often taller than wide in T.sect.....................................................................................................................—5

4. Papillae prominent on most of the abaxial 
leaf surface, the marginal cells appearing
sinuous (Fig. 28); El Salvador to NE
Mexico...............—3a. T. globosa var. globosa

4. Papillae less prominent on midrib and 
marginal zone than on stomata band, the
marginal cells ±rectangular (Fig. 29); 
Mexico (Nuevo/Tamaulipas, Veracruz), 
U.S. (Florida)...—3b T. globosa var. floridana

        Fig. 28. Abaxial surface near mid region of leaf, drawn from
            leaf fragment of type from Mexico


         Fig. 29. Similar type of section as above, drawn from leaf fragment of
          type from Florida

5. Stomata 7–10 (-12 rows); China (Yunnan, Sichuan)............................................................... —2. Taxus florinii  

5.  Stomata 4–7 (-9) rows; Pacific NW America.......................................................................—1. Taxus brevifolia

Fig. 30–33: Taxus florinii.  From left to right, Fig. 30: from Sichuan, China, Fliegner et al. 1129 (K), showing sharp contrast in color between upper and lower leaf surfaces. Fig. 31: from NW Yunnan, with pale yellowish seed on young shoot, Rock 18502 (US). Fig. 32–33: T-section (above) and abaxial view (below) of leaf near margin (mid region of leaf), showing variation in length and shape of cells, Fig. 32 from Yunnan, Yu 7848 (BM), Fig. 33 from Sichuan, Schneider 2918 (K). This species has leaf characteristics between T. globosa and T. brevifolia, distinguished from them mostly by slightly shorter cells in height on the abaxial (ventral) leaf surface.