A morphological study on the question of the hybrid origin of Astrophytum coahuilense (Cactaceae)


  • Richard R. Montanucci Clemson University




Two alternative hypotheses may explain the origin of Astrophytum coahuilense. One hypothesis is that A. coahuilense is an ancient diploid hybrid derived from interbreeding between A. capricorne and A. myriostigma. An alternative is that A. coahuilense arose via allopatric speciation and its similarity to A. myriostigma in vegetative characters is due to convergent evolution. The two hypotheses are tested, applying univariate analysis and Non-metric Multidimensional Scaling analysis to morphological datasets. Univariate analysis, which is based on 13 vegetative and 10 reproductive characters, shows that the morphology of A. coahuilense is complex, consisting of a combination of vegetative and reproductive characters shared with both A. capricorne and A. myriostigma as well as several intermediate traits. Furthermore, the morphology of A. coahuilense lacks unique, fixed characteristics. Non-metric Multidimensional Scaling analysis of 15 characters (three vegetative and 12 reproductive traits) produced a two-dimensional scatterplot in which the cluster representing A. coahuilense occupies a position intermediate between the clusters of the two parental species along Dimension 1. Thus, both analyses support the hypothesis that Astrophytum coahuilense originated through hybridization between A. capricorne and A. myriostigma. Biological and ecological factors that may have facilitated homoploid hybrid speciation are discussed.


ANDERSON, E. 1948. Hybridization of the habitat. Evolution 2:1–9.

BACKEBERG, C. 1961. Die Cactaceae. vol. 5. Jena: VEB Gustav Fischer Verlag.

BECERRA, L.J.L. 2009. Análisis de las caracteristicas de flotabilidad de la semilla de Astrophytum myriostigma Lem. (1839). Tesis de Licenciatura. Escuela Superior de Biología-UJED, Gómez Palacio, Durango, México.

BERNHARD, U. 1987. At the habitat of Astrophytum coahuilense. Brit. Cactus Succ. J. 5:106–111.

BLAIR, A.W. & P.S. WILLIAMSON. 2008. Effectiveness and importance of pollinators to the star cactus (Astrophytum asterias). S. W. Naturalist 53:423–430.

BLAIR, A. W. & P.S. WILLIAMSON. 2010. Pollen dispersal in star cactus (Astrophytum asterias). J. Arid Environm. 74:525–527.

BREGMAN, R. 1988. Forms of seed dispersal in Cactaceae. Acta Bot. Neerl. 37:395–402.

BUERKLE, C.A., R.J. MORRIS, M.A. ASMUSSEN, & L.H. RIESEBERG. 2000. The likelihood of homoploid hybrid speciation. Heredity 84:441–451.

CZAJA, A., M.R. PALACIOS-FEST, J.L. ESTRADA-RODRÍGUEZ, U. ROMERO MENDEZ, & J.A. ALBA ÁVILA. 2014. Inland dunes fauna and flora from Paleolake Irritila in the Comarca Lagunera, Coahuila, northern Mexico. Bol. Soc. Geol. Mexicana 66:541–551.

DAS, A.B., S. MOHANTY, & P. DAS. 2000. Cytophotometric estimation of 4C DNA content and chromosome analysis in four species of Astrop-hytum Lem. of the family Cactaceae. Cytologia 65:141–148.

DAS, A.B. 2008. Assessment of genetic diversity and phylogenetic analysis of “Star Cacti” (Astrophytum) through chromosome and RAPD markers. Cytologia 73:179–188.

GALTIER, N. & V. DAUBIN. 2008. Dealing with incongruence in phylogenomic analyses. Philos. Trans. Royal Soc. B: Biol. Sci. 363:4023–4029

GÁNDARA, E. & V. SOSA. 2014. Spatio-temporal evolution of Leucophyllum pringlei and allies (Scrophulariaceae): A group endemic to North American xeric regions. Molec. Phylogen. Evol. 76:93–101.

GIBSON, A.C. & P.S. NOBEL. 1986. The Cactus Primer. Harvard University Press, Cambridge, MA, U.S.A.

GRANADOS-AGUILAR, X., U. ROSAS, A. GONZÁLEZ-RODRÍGUEZ, & S. ARIAS. 2022. The prickly problem of interwoven lineages: Hybridization processes in Cactaceae. Bot. Sci. 100(4):797–813.

GRANT, V. 1958. The regulation of recombination in plants. Cold Spring Harbor Symp. Quant. Biol. 23:337–363.

GRANT, V. 1981. Plant speciation (Second Edition). Columbia University Press, NY, U.S.A.

GROSS, B.L. & L.H. RIESEBERG. 2005. The ecological genetics of homoploid hybrid speciation. J. Heredity 96:241–252.

HAAGE, W. & O. SADOVSKÝ. 1957. Kakteen Sterne, die Astrophyten. Radebeul: Neumann-Verlag.

HOOCK, H. 1988. Schutz der Nektarkammer bei Astrophytum-Blüten. Kakteen And. Sukk. 39:58–61.

HOOCK, H. 1990a. Astrophytum capricorne v. senile (Fric) Okumura. Kakteen And. Sukk. 41:28–30.

HOOCK, H. 1990b. Astrophytum capricorne v. senile (Fric) Okumura. Kakteen And. Sukk. 41:56–60.

HOOCK, H. & H. BAUMANN. 1991. In der Heimat von Astrophytum coahuilense (Moeller) Kayser. Kakteen And. Sukk. 42:214–218.

HOOCK, H. 1993. Ist Astrophytum coahuilense (Moeller) Kayser ein Naturhybrid? Kakteen And. Sukk. 44:37–44.

HOOCK, H. 2008. Astrophytum Lem. (Cactaceae). Landshut: Schoendruck-media e. K.

KATAGIRI, S. 1953. Chromosome numbers and polyploidy in certain Cactaceae. Cact. Succ. J. (Los Angeles) 25:141–142.

KAYSER, K. 1932. Astrophytum myriostigma subspecies Tulense. Der Kakteenfreund 1(6):57–59.

KLAUS, W. 1976. Wuchsformen von Astrophytum coahuilense (Moeller) Kayser. Kakteen And. Sukk. 27:160–162.

KLESZEWSKI, K.P. 2010. Bischofsmützen – Sternflanzen. Die Gattung Astrophytum. Deutsche Kakteen-Gesellschaft e. V., Pforzheim, Germany

LOERA, I, V. SOSA, & S.M. ICKERT-BOND. 2012. Diversification in North America arid lands: niche conservatism, divergence and expansion of habitat explain speciation in the genus Ephedra. Molec. Phylogen. Evol. 65:437–450.

LUX, A. & R. KOPUNEC. 1992. Gaseous and liquid phase water uptake by the stem surface of Astrophytum (Cactaceae). Environm. Exp. Bot. 32:75–81.

MACHADO, M.C. 2008. What is the role of hybridization in the evolution of the Cactaceae? Bradleya 26:1–18.

MARTÍNEZ-ADRIANO, C.A., U. ROMERO-MÉNDEZ, J. FLORES, E. JURADO, & E. ESTRADA-CASTILLÓN. 2015. Floral visitors of Astrophytum myriostigma in La Sierra El Sarnoso, Durango, Mexico. S. W. Naturalist 60:158–165.

MCDONALD, C.J. & G.R. MCPHERSON. 2005. Pollination of Pima Pineapple Cactus (Coryphantha scheeri var. robustispina): Does pollen flow limit abundance of the endangered species? USDA Forest Service Proc. RMRS-P-36:529–532.

MCCARTHY, E.M., M.A. ASMUSSEN, & W.W. ANDERSON. 1995. A theoretical assessment of recombinational speciation. Heredity 74:502–509.

MEGATA, M. 1944. An account of the genus Astrophytum Lemaire. Mem. College Agric., Kyoto Imperial Univ. Pp. 1–62, 10 plates.

METCALFE, S. E. 2006. Late Quaternary environments of the northern deserts and central transvolcanic belt of Mexico. Ann. Missouri Bot. Gard. 93:258–273.

MÖLLER, H. 1927. Beobachtungen an Astrophyten. Zeitschrift für Sukkulentenkunde 3(3):52–54.

Montanucci, R.R. 2008. Taxonomic history and status of the Coahuila Bishop’s Cap. Haseltonia 14:176–184.

MONTANUCCI, R.R. 2009. Infrageneric taxonomy of Astrophytum (Cactaceae), with remarks on the status of Digitostigma. J. Bot. Res. Inst. Texas 3:251–256.

MONTANUCCI, R.R. 2015. Experimental evidence for reproductive isolation between Astrophytum coahuilense (H. Möller) Kayser and A. capricorne var. senile (Fric) Okumura (Cactaceae). Haseltonia 20:13–21.

MONTANUCCI, R.R. & K.P. KLESZEWSKI. 2021. Taxonomic history, comparative morphology, and variation in Astrophytum myriostigma and its subspecies tulense. J. Bot. Res. Inst. Texas 15(2):327–341.

NEFF, J.L. & B.N. Danforth. 1991. The nesting and foraging behavior of Perdita texana (Cresson) (Hymenoptera: Andrenidae). J. Kansas Entomol. Soc. 64:394–405.

RIESEBERG, L.H. 1997. Hybrid origins of plant species. Ann. Rev. Ecol. Syst. 28:359–389.

RIESEBERG, L.H. & D.E. SOLTIS. 1991. Phylogenetic consequences of cytoplasmic gene flow in plants. Evol. Trends Pl. 5:65–84.

RIESEBERG, L.H., B. SINERVO, C.R. LINDER, M.C. UNGERER, & D.M. ARIAS. 1996a. Role of gene interactions in hybrid speciation: evidence from ancient and experimental hybrids. Science 272:741–745.

RIESEBERG, L.H., J. WHITTON, & C.R. LINDER. 1996b. Molecular marker incongruence in plant hybrid zones and phylogenetic trees. Acta Bot. Neerl. 45:243–262.

RIESEBERG, L.H. and S.E. CARNEY. 1998. Plant hybridization. New Phytology 140:599–624.

RIESEBERG, L.H., M.A. ARCHER, & R.K. WAYNE. 1999. Transgressive segregation, adaptation, and speciation. Heredity 83:363–372.

ROSS, R. 1981. Chromosome counts, cytology, and reproduction in the Cactaceae. Amer. J. Bot. 68:463–470.

SADOVSKÝ, O. & B. SCHÜTZ. 1979. Die Gattung Astrophytum. Arten. Hybriden. Kultur. Flora-Verlag, Titisee-Neustadt, Germany.

SCHEINVAR, E., N. GÁMEZ, G. CASTELLANOS-MORALES, E. AGUIRRE-PLANTER, & L.E. EGUIARTE. 2017. Neogene and Pleistocene history of Agave lechuguilla in the Chihuahuan Desert. J. Biogeogr. 44:322–334.

STEBBINS, G. L. 1957. The hybrid origin of microspecies in the Elymus glaucus complex. Cytologia Suppl. 36: 336–340.

TOMAN, V. 1978. Po?et a morfologie chromosom? Astrophytum asterias (Zuc.) Lem. Kaktusy 14:89–92.

UNGERER, M.C., S. J.E. BAIRD, J. PAN, & L.H. RIESEBERG. 1998. Rapid hybrid speciation in wild sunflowers. Proc. Natl. Acad. Sci. 95:11757–11762.

VÁZQUEZ-LOBO, A., G.A. MORALES, S. ARIAS, J. GOLUBUV, T. HERNÁNDEZ-HERNÁNDEZ, & M.C. MANDUJANO. 2015. Phylogeny and biogeographic history of Astrophytum (Cactaceae). Syst. Bot. 40:1022–1030.

WENDEL, J.F. & J.J. DOYLE. 1998. Phylogenetic Incongruence: Window into Genome History and Molecular Evolution. In: Soltis, D.E., Soltis, P.S., Doyle, J.J., eds. Molecular systematics of plants II. Springer, Boston, MA, U.S.A.

ZHANG, Q., Y. LIU, & SODMERGEN. 2003. Examination of the cytoplasmic DNA in male reproductive cells to determine the potential for cytoplasmic inheritance in 295 Angiosperm species. Pl. Cell Physiol. 44(9):941–951.




How to Cite

Montanucci, R. R. (2024). A morphological study on the question of the hybrid origin of Astrophytum coahuilense (Cactaceae). Journal of the Botanical Research Institute of Texas, 18(1), 163–185. https://doi.org/10.17348/jbrit.v18.i1.1346