Cladocolea spathiflora Galván-Gonz., Cerros, Espejo & López-Ferr., 2017

Galván-González, Luis Gil, Cerros-Tlatilpa, Rosa, Espejo-Serna, Adolfo & López-Ferrari, Ana Rosa, 2017, Cladocolea spathiflora (Loranthaceae) a new species from Guerrero, Mexico, Phytotaxa 308 (2), pp. 295-300 : 295-299

Cladocolea spathiflora Galván-Gonz., Cerros, Espejo & López-Ferr. , spec. nov. Fig. 1 , Fig. 3 A, D, G, J, M

Cladocolea spathiflora is similar to C. grahamii (Bentham) van Tieghem , and C. pringlei Kuijt from which it differs by its flowers associated to a spathaceous receptacle formed by the fusion of pedicel and floral bract.

Type:— MEXICO, Guerrero: municipio de Eduardo Neri: 3.1 km al SW de El Miraval, carretera federal Miraval a Filo de Caballos, 2,159 m.a.s.l., 17°42’31.2“N, 99°46‘32.7“W, 20 April 2017. L. G. Galván G., R. Cerros T. & M. I. Miguel V. 254 ♂ (holotype: HUMO!, isotype: UAMIZ!).

Scandent shrubs with pendant shoots, to 2 m long, dioecious. Stems angulate to quadrangulate, becoming cylindrical when mature, glabrous, caulinar roots on mature stems. Leaves alternate to opposite, regularly three pseudoverticillate leaves, petiole 1.4–5.7 mm long; blades ovate to lanceolate, rarely elliptic, 2.8–7.3 × 1.1–2.9 cm, base cuneate to attenuate, margin corky, apex acute, obtuse or rounded, glabrous, venation of three middle veins with lateral branching, resembling pinnate venation. Inflorescences racemose, indeterminate, rarely determinate, present only in mature branches, 1(–2) by foliar axil; male inflorescences 0.7–3.2 cm long, with 13–21 flowers, peduncle 0.4–2.7 mm long; female inflorescences 0.7–1.8 cm long, with 9–20 flowers; peduncle 0.2-1.9 mm long; pedicel and floral bract fused and forming a spathaceous receptacle, 2.2–6.3 × 1.9–3.6 mm, associated to the flowers. Male flowers hexamerous, rarely octamerous, floral buds clavate, apex rounded, mature flowers 6.7–8.5 × 3.8–6.5 mm; calyx 2–4 lobed to irregularly dentate, 1.1–1.5 mm long; petals 5.7–7.5 × 0.9–1.5 mm, unicellular trichomes on the adaxial surface, stamens disposed in two unequal series, the short ones 4.0– 6.1 mm, the long ones 5.1–7.2 mm, filaments adnate to petals, free in the apical portion, surface bullate, anthers 1.7–2.4 × 0.7–1.3 mm, projection of the connective acute to rounded; vestigial ovary 0.8–1.3 × 1.5–2.1 mm, style 4.9–6.1 mm long, tortuous at central and apical portions; female flowers hexamerous, floral buds cylindrical, apex rounded, mature flowers 6.7–7.9 × 4.2–5.7 mm, calyx 2–4 lobed to irregularly dentate, 1.3–1.9 mm long; petals 5.9–7.5 × 0.9–1.2 mm, unicellular trichomes on the adaxial surface; staminodes with sterile anthers, disposed in two unequal series, the short ones 4.3–5.5 mm long, the long ones 5.3–6.8 mm long, filaments entirely adnate to petals, surface bullate; anthers 0.9–1.4 × 0.6–0.8 mm, projection of the connective obtuse to rounded, ovary 0.8–1.5 × 1.5–2.3 mm, style 5.5–6.9 mm long, undulate to tortuous in the superior half, with 2–4 vertical or horizontal folds. Infructescence 1.1–2.1 cm long, receptacle concrescent, 2.4–3.3 × 3.5–4.7 mm. Fruits ellipsoid, 1.6–2.7 × 0.5–0.7 mm.

Distribution and habitat: — Cladocolea spathiflora is known from two regions of the municipality of Coyuca de Catalán and between the municipal boundaries of Eduardo Neri and Leonardo Bravo, in the state of Guerrero ( Fig. 2 ). It is a parasitic plant of oak trees in pine-oak forests, between 1,860 and 2,170 m.a.s.l. It flowers from February to June, the fruits have been reported from March to April. Pollination is carried out by bees.

Ethimology: —The specific epithet refers to the spathaceous resemblance of the receptacle, formed by the fusion of the pedicel and the floral bract.

Comments: —Herbarium specimens of Cladocolea spathiflora may be confused with dried material of C. grahamii (Benth.) Tiegh. or C. pringlei Kuijt , particularly when the inflorescences are immature. However, the new taxon differs of both species in having regularly three pseudoverticillate leaves, a spathaceous receptacle that support each flower instead of sessile flowers on the axis inflorescences, a tuft of hairs in the adaxial surfaces of the petals in female flowers and staminodes with sterile anthers. Additional differences among these taxa are shown in Table 1 and Figure 3 .

Additional specimens examined: — MÉXICO, Guerrero, municipio de Coyuca de Catalán: La Laguna, distr. Mina, 1,860 m.a.s.l., 7 may 1937, G. B. Hinton et al. 10149 ♂ ( ENCB!) ; municipio de Eduardo Neri: 0.7 km al SO de Tres cruces, carretera federal Miraval-Filo de Caballos , 2,171 m.a.s.l., 20 apr 2017, L. G. Galván G., R. Cerros T. & M. I. Miguel V. 255 ♂ ( HUMO!, UAMIZ!) ; 4 km después del Mirabal [El Miraval], carretera Xochipala-Filo de Caballos , 2,130 m.a.s.l., 23 mar 1981, A. R. López F. 37 ♀ ( FCME (× 2)!) ; Chichihualco, en Mirabal [ El Miraval ], 23 km al SW de Xochipala, 2,050 m.a.s.l., 19 apr 1989. J. C. Soto N. & S. Aureoles C. 8258 ♂ ( MEXU!) ; municipio de Leonardo Bravo: aproximadamente 4 km al SW de El Mirabal [ El Miraval ], 2,140 m.a.s.l., 21 feb 1981, F. G. Lorea 1051 ♂ ( FCME (× 2)!) ; a 26 km al W de Xochipala, camino a Filo de Caballos , 2,060 m.a.s.l., 12 jun 1982, E. Martínez S. 749 ♀ ( MEXU!) .

Figures

FIGURE 1. Cladocolea spathiflora.A. Herbarium specimen (L. G. Galván G., R. Cerros T.& M. I. Miguel V. 254). B. Male inflorescence. C. Apical portion of the inflorescence with a fertile bract (fb) and sterile bracts (sb) (J. C. Soto N. & S. Aureoles C. 8258). D–E. Male flowers. F. Infructescence with concrescent receptacles (A. R. López F. 37). G. Dissection of a male flower (J. C. Soto N. & S. Aureoles C. 8258). H. Dissection of a female flower (A. R. López F. 37). Scale bars = 2 mm. Photos. L. G. Galván-González & R. Cerros-Tlatilpa.

FIGURE 2. Distribution map of Cladocolea spathiflora, C. grahamii, and C. pringlei in Mexico.

FIGURE 3. Morphological features of Cladocolea spathiflora, C. grahamii, and C. pringlei. A, B, C. Leaf arrangement leaves in C. spathiflora (L. G. Galván G. 254), C. grahamii (L. G. Galván G. 256), and C. pringlei (L. J. Hernández B. 172) D, E, F. Leaf margin texture of C. spathiflora (J. C. Soto N. & S. Aureoles C. 8258), C. grahamii (O. Villafranco 105), and C. pringlei (L. G. Galván G. 238b). G, H, I. Male inflorescences of C. spathiflora (L. G. Galván G. 254), C. grahamii (S. E. Ramírez D. 18), and C. pringlei (L. G. Galván G. 241). J, K, L. Staminode apex of C. spathiflora (A. R. López F. 37), C. grahamii (A. Alonso A. s. n.), and C. pringlei (J. C. Soto N. 5694), arrows points trichomes. M, N, O. Filament surface of male flowers of C. spathiflora (J. C. Soto N. & S. Aureoles C. 8258), C. grahamii (S. E. Ramírez D. 18), and C. pringlei (L. G. Galván G. 241). Photos. L. G. Galván-González & R. Cerros-Tlatilpa.