FNA: Photinia vs. Rosaceae tribe Maleae

Distribution

Mexico; Central America; Asia [Introduced in North America; introduced also in Europe, Pacific Islands (Hawaii, New Zealand), Australia]

[BONAP county map]

HI; North America; Mexico; Central America; Eurasia; Africa; Atlantic Islands (Madeira) [Introduced in temperate southern hemisphere]

Discussion

Species 40–60 (4 in the flora).

Photinia is widely introduced in cultivation and naturalizing, at least in the continental United States. Species are native mostly to warm temperate Asia, from the Himalayas east to Japan and south to India and Thailand. Molecular data suggest that Heteromeles originated through hybridization, with a species of Photinia as pollen parent (Guo W. et al. 2011).

Five species from Mexico and Central America were included within Photinia by J. B. Phipps (1992) and molecular evidence corroborates their placement there (Guo W. et al. 2011).

The Asian Stranvaesia has sometimes been treated as distinct from Photinia, but botanists have noted the apparent artificiality of a primary character used to differentiate the two genera, namely an endocarp dehiscent in Stranvaesia, indehiscent in Photinia (C. Kalkman 1973; J. B. Phipps et al. 1991b; K. R. Robertson et al. 1991; J. R. Rohrer et al. 1991, 1994). Kalkman observed that the putative dehiscence of Stranvaesia carpels is an artifact of specimen preparation. Rohrer et al. (1991, 1994) found that Photinia and Stranvaesia do not differ in connation of the carpels or in the adnation of the carpels to the hypanthium. Molecular phylogenetic analyses (Guo W. et al. 2011) show that the Stranvaesia species have arisen within the cladistic topology of Photinia.

The primarily eastern North American genus Aronia (for example, A. floribunda, A. melanocarpa) has been included in Photinia in some classifications (K. R. Robertson et al. 1991) but is here treated as distinct.

Many species of Photinia are ornamental trees and shrubs with large lustrous leaves and masses of white flowers in the spring followed by red fruits in the fall. The flowers last about two weeks and commonly have an unpleasant smell. The wood is hard and heavy and has been used for furniture and small articles such as axe handles.

Photinias have been widely and abundantly planted for hedging in the southeastern United States. The rapid spread since about the mid 1980s of a fungal leaf spot, Entomosporium maculatum, has been lethal to many such hedges. Photinia ×fraseri ('red tip'; see under 2. P. serratifolia) and P. glabra are severely affected; P. serratifolia is said to be partially resistant.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Genera 29, species 550–840+ (18 genera, 270 species, including 18 hybrids, in the flora).

The family name Malaceae Small (1903) is a conserved name, with Malus as its type genus. In contrast, the family name Pyraceae Vest (1818), with Pyrus as its type, is not a conserved name. Although Maleae was published later than Pyreae (1869), a Rosaceae tribe that includes both Malus and Pyrus is to be called Maleae (see Melbourne Code, Article 19.5, Example 5).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key

1. Leaf margins entire.	P. davidiana
1. Leaf margins usually serrate or crenate-serrulate	→ 2
2. Leaves deciduous, blades herbaceous; inflorescences 3–6 cm diam.; pedicels with warty lenticels.	P. villosa
2. Leaves persistent, blades coriaceous; inflorescences 4–18 cm diam.; pedicels without lenticels	→ 3
3. Leaf blades 5–9 cm, lateral veins 10–15(–18) pairs, margins crenate-serrulate; inflorescences 4–10 cm diam.	P. glabra
3. Leaf blades (6–)9–20 cm, lateral veins 20–30 pairs, margins sharply serrate to inconspicuously toothed or entire; inflorescences 10–18 cm diam.	P. serratifolia

1. Leaf margins usually horny; carpels free; flowers: perianth and androecium perigynous; fruits woody capsules surrounded by a hypanthium, splitting into 5 follicles; seeds winged	Vauquelinia
1. Leaf margins not horny; carpels ± adnate to hypanthium; flowers: perianth and androecium epigynous; fruits pomes; seeds not winged or pyrenes.	→ 2
2. Fruiting carpels woody or bony.	→ 3
3. Leaf margins entire; stipules short-adnate to petiole; stems unarmed; sepals erect in flower; petal base clawed.	Cotoneaster
3. Leaf margins ± serrate, crenate, serrulate, or crenulate, sometimes entire; stipules free; stems usually armed (sometimes with compound thorns), sometimes unarmed; sepals spreading in flower; petal base slightly or barely clawed.	→ 4
4. Leaves persistent or late-deciduous; flowers 3–10(–12) mm diam., hypanthium campanulate; pomes 3–8 mm diam.	Pyracantha
4. Leaves deciduous (sometimes winter-persistent in south); flowers 8–35 mm diam., hypanthium ± obconic; pomes 6–40 mm diam.	→ 5
5. Flowers 8–25 mm diam., stamens 5–20 (rarely 30–45); pomes yellow to red or purplish to black mature, 6–20(–25) mm diam.; pyrenes 1–5; short shoots present; inflorescences 1–50-flowered, domed panicles, corymbose, or flowers solitary.	Crataegus
5. Flowers 25–35 mm diam., stamens 25–35(–40); pomes brownish, 15–40 mm diam.; pyrenes 5; short shoots rare or absent; inflorescences 1(or 2) flowered	Mespilus
2. Fruiting carpels cartilaginous.	→ 6
6. Stems armed (thorns present).>	→ 7
7. Stipules persistent; pedicels short or absent; styles basally connate 1/3 of length; pome flesh without stones; stamens 40–60; fruiting sepals deciduous.	Chaenomeles
7. Stipules usually deciduous or caducous; pedicels present; styles distinct or basally connate; pome flesh with stones (at least near carpels and epidermis); stamens 15–50; fruiting sepals persistent or deciduous.	→ 8
8. Pome flesh with stone cells adjacent to carpels and epidermis; styles basally connate.	Malus
8. Pome flesh with abundant stone or grit cells; styles distinct.	Pyrus
6. Stems unarmed.	→ 9
9. Inflorescences: flowers solitary or 1–5-flowered, corymbs or cymes.	→ 10
10. Pomes yellow; ovules (seeds) many; inflorescences: flowers solitary.	→ 11
11. Leaf margins entire, abaxial surfaces densely villous; buds ovoid, apices obtuse or acuminate, tomentose; young branches tomentose, glabrescent; stipules caducous; flowers 40–50 mm diam., petals white or light pink, suborbiculate, ovate, or obovate, stamens equal to or slightly longer than petals; pomes pyriform or subglobose, 30–50 mm.	Cydonia
10. Pomes pink, yellow-orange, purple, purplish or bluish black, brownish, or nearly black; ovules (seeds) (1 or)2; inflorescences 1–5-flowered, cymes or corymbs.	→ 12
12. Pomes yellow-orange; stipules adnate to petiole and base of blade; petioles short or absent; leaf blades elliptic to oblanceolate or linear.	Peraphyllum
12. Pomes pink, bluish or purplish black, purple, brownish, or nearly black; stipules free; petioles present; leaf blades elliptic, elliptic-oblong, or oblong-ovate to orbiculate.	→ 13
13. Leaves leathery, drought-deciduous or persistent; sepals nearly orbiculate (inner broadly deltate), petals round or kidney-shaped; carpels barely connate or distinct, styles lateral; pomes translucent, vivid pink, drying purplish black.	Malacomeles
13. Leaves membranous to coriaceous (not leathery), deciduous; sepals triangular to lanceolate, petals linear to orbiculate; carpels connate, styles terminal; pomes bluish or purplish to nearly black, pinkish or maroon-purple, dark purple-blue, or brownish.	Amelanchier
9. Inflorescences (4 or)5–400+-flowered, panicles, sometimes racemes, corymbs, or subumbellate.	→ 14
14. Leaves persistent, leathery; carpels basally adnate to hypanthium.	→ 15
15. Leaf margins flat; flowers 15–20 mm diam.; pedicels short or nearly absent; hypanthia usually tomentose; stamens 20; carpels connate, styles (2–)5; pomes soft apricot yellow, 20–30 mm (diam.).	Eriobotrya
15. Leaf margins revolute; flowers 10 mm diam.; pedicels present; hypanthia glabrous or weakly floccose; stamens 10; carpels distinct, styles 2 or 3; pomes usually bright red, sometimes yellow, 5–10 mm	Heteromeles
14. Leaves usually deciduous, sometimes semipersistent or persistent (then margin entire), membranous to ± leathery; carpels adnate to all or 1/3–1/2 of hypanthium.	→ 16
16. Pome flesh with stones or sclereids.	→ 17
17. Inflorescences terminal, 6–400+-flowered flat-topped or rounded panicles; flowers opening after leaf expansion, 5–17 mm diam.; sepals erect or ascending; leaves pinnately divided, sometimes simple or lobed.	Sorbus
17. Inflorescences terminal on short shoots, 4–9-flowered racemes or simple corymbs, umbel-like; flowers developing with or before leaves, 15–45 mm diam.; sepals reflexed; leaves simple.	Pyrus
16. Pome flesh without stones.	→ 18
18. Stipules adnate to petiole, persistent	Aronia
18. Stipules free, caducous or deciduous.	→ 19
19. Leaves persistent or deciduous; inflorescences corymbose or subumbellate; pomes red or black.	Photinia
19. Leaves deciduous; inflorescences racemes; pomes bluish or purplish to nearly black, pinkish or maroon-purple, dark purple-blue, or brownish	Amelanchier