Hylocereus, sect. Hylocereus clade)

Ruiz-Dominguez, Catalina, Vovides, Andrew P. & Sosa, Victoria, 2019, Systematic relevance of pollen morphology in tribe Hylocereeae (Cactaceae), PhytoKeys 128, pp. 121-140 : 127

Selenicereus (Hylocereus sect. Hylocereus clade)

Pollen.

trizonocolpate, radially symmetrical, isopolar with circular contour in polar view. Shape: varies from suboblate to subprolate (P/E=0.86-1.18). Apertures: 3, colpate (brevicolpate in S. minutiflorus ), large (small in S. minutiflorus ); polar area medium-sized to large (PAI=0.30-0.59). Measurements: pollen grains of medium to very large size, (54.52)78.67(97.83) × (45.94)83.68(102.53) μm in equatorial view; exine thickness (1.66)2.95(4.10) μm. Ornamentation: smooth surface with tectum perforate, ornated with spinules ( S. minutiflorus and S. stenopterus without spinules) of (1.06)1.47(2.13) μm length × (0.72)1.23(1.53) μm diameter in base; perforations (0.20)0.39(0.89) μm in diameter ( Figures 3D , 3E , 3F , 3G , 3I , 3J , 4A , 4E , 4F ).

Species examined.

Selenicereus costaricensis (F.A.C. Weber) Britton & Rose (Colombia, Valle del Cauca. C. Ruiz et al. 555 CUVC); S. escuintlensis Kimnach (Guatemala, Escuintla. C. Ruiz et al. 635 BIGU); S. guatemalensis (Eichlam ex Weing.) Britton & Rose (Guatemala, El Progreso. M. Véliz et al. 20227 BIGU); S. minutiflorus Britton & Rose (Guatemala, Izabal. C. Ruiz et al. 627 BIGU); S. monacanthus (Lemaire) Britton & Rose (Honduras, Francisco Morazán. C. Ruiz et al. 493 TEFH); S. polyrhizus (F.A.C. Weber) Britton & Rose (Colombia, Valle del Cauca. C. Ruiz et al. 566 CUVC); Selenicereus sp. ( México, Oaxaca. C. Ruiz et al. 608 XAL); S. stenopterus (F.A.C. Weber) Britton & Rose (Costa Rica, Alajuela. C.K. Horich s.n. MEXU); S. triangularis (L.) Britton & Rose ( México, Yucatán. C. Gómez-Hinostrosa 2110 MEXU); S. undatus (Haworth) Britton & Rose (Colombia, Valle del Cauca. C. Ruiz et al. 560 CUVC).

Figures

Figure 3. Pollen grains of tribe Hylocereeae (Scanning Electron Microscope photographs). Left polar view, right equatorial view A Acanthocereus tetragonus (C. Ruiz et al. 576) B Disocactus ackermanii (R. Torres et al. 309) C Epiphyllum oxypetalum (C. Ruiz et al. 640) D Selenicereus costaricensis (C. Ruiz et al. 555) E S. escuintlensis (C. Ruiz et al. 635) F S. guatemalensis (M. Veliz et al. 20227) G S. minutiflorus (C. Ruiz et al. 627) H S. ocamponis (M. Chazaro 7334) I S. polyrhizus (C. Ruiz et al. 566) J S. sp. (C. Ruiz et al. 608).

Figure 4. Pollen grains of tribe Hylocereeae (Scanning Electron Microscope photographs). A-D: Left polar view, right equatorial view A S. undatus (C. Ruiz et al. 560) B Weberocereus tunilla (C. K. Horich BGA 58344) C S. setaceus (H. Bravo et al. 2755). D-J: left polar view, left details of spinules and perforations D S. megalanthus (C. Ruiz et al. 563) E S. stenopterus (C. K. Horich s. n.) F S. triangularis (C. Gomez-Hinostrosa 2110) G Kimnachia ramulosa (L. Velasquez et al. 4884) H Pseudorhipsalis amazonica (E. Gudino 145) I S. alliodorus (A. Ruiz Velazco et al. 86) J S. glaber (C. K. Horich BGA 57239).