Note: Echinopsis pseudomelanostele (Werdermann & Backeberg) Anceschi & Magli is a new combination published in cactusinhabitat booklet South America 2011-2013 (Anceschi & Magli 2013b, 39). For the phylogenetic hypothesis adopted for the assimilation of Haageocereus Backeberg in Echinopsis Zuccarini see Anceschi & Magli (ibidem, 22-29).
July 2021
Note: For a number of years, molecular analysis has revealed the close relationship between Echinopsis s.l. and the other genera within the tribe Trichocereeae, or subtribe Trichocereinae (Nyffeler 2002, 317- 319; Schlumpberger 2009; Lendel et al. 2006, unpubl. data in Nyffeler & Eggli 2010). Even the more recent molecular analysis of Echinopsis (Schlumpberger & Renner 2012) has clearly demonstrated that a cladistically correct interpretation of the molecular data, in the direction of a monophyletic genus Echinopsis, leads to the assimilation in Echinopsis s.l., as currently conceived (Anderson 2001; Hunt et al. 2006; Anderson & Eggli 2011), of Cleistocactus Lemaire, Denmoza Britton & Rose, Haageocereus Backeberg, Harrisia Britton, Oreocereus (A. Berger) Riccobono, Weberbauerocereus Backeberg and 10 other genera of the Trichocereeae/Trichocereinae. We've dealt extensively with the subject, in the part devoted to the taxonomy in our penultimate booklet (Anceschi & Magli 2013b, 22-29). Our position is summarized in “The new monophyletic macro-genus Echinopsis. No risk of paraphyly, and the most convincing hypothesis in phylogenetic terms” appeared on Cactaceae Systematics Initiatives N° 31, pages 24-27 (August 2013).
Hunt et al. (2006, text: 136), divide Haageocereus pseudomelanostele (Werdermann & Backeberg) Backeberg into 5 ssp., recognizing in addition to the type ssp., the following ssp. acanthocladus, aureispinus, chryseus and turbidus. The same ssp. are also recognized in Anderson & Eggli (2011, 334-335), with the exclusion of ssp. acanthocladus, which is believed to be synonymous with H.pseudomelanostele, and the addition of ssp. carminiflorus, considered synonymous with ssp. pseudomelanostele by the first authors (Hunt et al. 2006, text: 136). The surveys we carried out in 2014 in the coastal desert of Peru, on the populations of Echinopsis pseudomelanostele (Werdermann & Backeberg) Anceschi & Magli, in the Nazca-Huallhua valley, corresponding to ssp. turbidus, and in the Lima-Matucana valley (Rio Rimac valley), corresponding to ssp. pseudomelanostele, have highlighted that the only distinctive element for the first, are the more evident spines (thicker and whitish) on the majority of the individuals, see A&M 1171, Peru, Ica, north-east of Nazca, 862m (photo 5); although there is no lack of semaphoronts (Hennig 1966, 6-7, 32-33, 63, 65-67) young (photo 8), or adults, see A&M 1176, ibidem, 1147 m (photos 41-42), bearing thinner spines, golden or brown yellow colored, and are perfectly in line with their correspondents of the Lima Valley (Rimac Valley), see A&M 1218, Peru, Lima, Lima, north-east of Lima (photos 51-52, for adults semaphoronts, and photos 55-56 for both young and adults semaphoronts). Even the concise descriptions of ssp. acanthocladus, aureispinus, and chryseus in Hunt et al. (2006, text: 136), do not highlight any differences worthy of note, compared to the type species, if not the name. The poor distinction between the taxa in question is also highlighted by the photos chosen by the authors to represent them (ibidem, atlas: 185-186). This little distinction is confirmed also by the photo that identifies Haageocereus chryseus F. Ritter (the ssp. Chryseus), in Ritter (1981, 4: 1520, fig. 38), substantially the same for spination and colors as a specimen of H. pseudomelanostele. For the above reasons, the additional taxa proposed by Hunt et al. are not justifiably distinct to split up the populations of the dominant E. pseudomelanostele; and we consider them redundant, and that they ought to be added to the synonymy of the species. To clarify our taxonomic understanding of E. pseudomelanostele, we note that its synonym Haageocereus pseudomelanostele, is considered by E. A. Molinari-Novoa (2015, 13: 19) to be among the synonyms of Echinopsis multiangularis (Haworth) Molinari, having the basionym Cereus multiangularis Haworth, previous the latter (1819) to Cereus pseudomelanostele (1931), basionym of E. pseudomelanostele. In this regard, we recall that Hunt et al. (2006, text: 136) rejected Haageocereus multiangularis (Haworth) F. Ritter with the basionym Cereus multiangularis Haworth [not Cactus multiangularis Willd (1814), also rejected] = Haageocereus pseudomelanostele? We also recall that Eggli, in Anderson & Eggli (2011, 335, 668), also expressed a similar position, reporting that C. multiangularis cannot be identified with certainty as H. pseudomelanostele. Based on these considerations, we prefer to identify the populations in question with the name Echinopsis pseudomelanostele. While choosing E. multiangularis instead of E. pseudomelanostele, E. A. Molinari-Novoa (2015, 13: 19) also considered the epithets acanthocladus, aureispinus, carminiflorus and turbidus as synonyms; ssp. chryseus is not summarized by the author, as absent in the Department of Lima, the subject of his updated list. (Quoted fromAnceschi & Magli 2021, 63-64)
In August 2013, following publication of our 2011/2013 booklet (June 2013), we published an article relating to the discussed monophyly of Echinopsis Zuccarini s.l. in Cactaceae Systematics Initiatives (2013b, 31: 24-27). That article summarized and underlined the position we have taken in the booklet in relation to the phylogenetic hypothesis to be adopted regarding the classification of the genera related to Echinopsis s. l., within the tribe Trichocereeae, or subtribe Trichocereinae (Nyffeler 2002, 317, 319; Lendel et al. 2006, unpubl. data in Nyffeler & Eggli 2010), between the two shown by the results from the molecular analysis carried out by Schlumpberger & Renner (2012: 1335 -1349). According to them, to avoid the polyphyly of Echinopsis s.l. as conceived at the time (Anderson 2001, 2005, 2011; Hunt et al., 2006; Nyffeler & Eggli 2010), there were two possible solutions:
I) A new division of Echinopsis s. l. in at least 7 old genera (Acanthocalycium, Chamaecereus, Leucostele, Lobivia, Reicheocactus, Soehrensia and Setiechinopsis). This is the option adopted by Schlumpberger, which led to the 48 new combinations presented by him in CSI (28: 29-31). This was a solution devoid of internal coherence, as it did not naturally resolve the internal relationships of the clades Cleistocactus sens. str. and Oreocereus (Schlumpberger & Renner 2012: 1342; Anceschi & Magli 2013b, 31: 25).
II) The other solution was constituted by the inclusion of 15 genera hitherto never incorporated before in Echinopsis s.l., as indicated by the analysis (Schlumpberger & Renner 2012: 1336, 1341), to make the genus monophyletic in Hennig’s sense. The latter, as we know, is the hypothesis we supported (Anceschi & Magli 2013a, 22-29; 2013b, 31: 24-27). Referring to the aforementioned booklet and to the article in CSI for all the insights related to the matter treated at that time, we now update what is known, with the following notes:
I) Of the 15 genera often cited to be assimilated in Echinopsis s.l., for the constitution of a monophyletic macrogenus Echinopsis, actually just 6 of these are monotypic genera (i.e. composed of only one species): Denmoza, Mila, Rauhocereus, Samaipaticereus, Vatricania, Yungasocereus; and according to Hunt (2003, 15: 3) "The monotypic genus is a contradiction in terms. Logically (or at least etymologically) the term genus implies a class or group of things of a lower order (in botany, species etc.), i.e. a collection of things with common attributes. ". Not to mention that 2 of the genera in question (Oroya and Pygmaeocereus), are composed of only two species. It is therefore evident that the aforementioned transfer to Echinopsis involves in reality far fewer natural taxa than those which would seem to be initially implicated.
II) it is striking that of the 17 naturally-occurring intergeneric hybrids reported by Hunt et al. (2006, text: 321) and taken from Hunt (2015, 33: 16) for the family Cactaceae, as many as 11 concern the alleged genera within the tribe Trichocereeae, or subtribe Trichocereinae, i.e. 1) xCleistocana (Cleistocactus x Matucana), 2) xEchinomoza (Echinopsis x Denmoza), 3) xEspocana (Espostoa x Matucana), 4) xEspostingia (Espostoa x Rahuocereus), 5) xEspostocactus (Espostoa x Cleistocactus), 6) xHaagespostoa (Haageocereus x Espostoa), 7) xMaturoya (Matucana x Oroya), 8) xOreocana (Oreocereus x Matucana), 9) xOreonopsis (Oreocereus x Echinopsis),10) xWeberbostoa (Weberbauerocereus x Espostoa), 11) xYungastocactus (Yungasocereus x Cleistocactus). We would like to remember, assuming that the term genus still has some meaning in biology and classification, that two genera that are such, that by definition cannot cross with each other, and if not, they are not two distinct genera.
III) Regarding the 'judgment' repeatedly expressed by Hunt (2013, xiii; 2018, 39: 5, 11), "This radical option has been espoused by Anceschi & Magli (2013) but seems unlikely to gain many supporters", related to our taxonomic approach to the solution of the Echinopsis classification problem, a judgment which has already been denied by Molinari-Novoa (2015, 13: 18-21) and by Mayta & Molinari-Novoa (2015, 14: 13-20), we wonder: since when being "radical" would compromise the use of a solution in science, if this is the one that best represents the correct interpretation of the theory in use?
IV) As already stated in our synopsis of the genus Parodia Spegazzini s.l. (Anceschi & Magli 2018, 36: 75), recent molecular analysis (Barcenas et al. 2011, 27: 470-489), have clearly highlighted that most of the genera of the Cactaceae as currently understood are not monophyletic in Hennig's sense (i.e. not sufficiently extended and not supported by a sufficient number of synapomorphies (see Anceschi & Magli 2018, 36: 74-75), or as in the authors’ words “... our least inclusive groupings are significantly larger than currently accepted genera ... However, although many genera are not monophyletic, many of these follow a pattern of a monophyletic core, with one or two outliers suggesting relatively robust groups with 'fuzzy edges' so that in several cases small adjustments to classifications (i.e. moving outside of the genus) may produce monophyletic groups without significant nomenclatural changes. " (ibidem, 488). Regarding this way of operating, we think that the science of classification has reached a crossroads:
a) correctly apply the available theories to the evidence that science shows us through the techniques and tools currently in use (in this case the principle of monophyly in Hennig's sense (1966), having regard to the opposition that is made of the mentioned principle with the concepts of polyphyly and paraphyly, being the second a new concept proposed by this author (see Anceschi & Magli 2018, 36: 74-75).
b) continue to use the paradigms of collecting to distinguish taxa or, if preferred, with the contemporary tools at hand, the use of the 'cynical' species concept, which is, summarized in Kitcher's words as follows: "Species [and genera] are those groups of organisms which are recognized as species [or genera] by competent taxonomists. Competent taxonomists, of course, are those who can recognize the true species [or genera]. " (1984 (51) 2: 308). We think that Hunt's solution (2013, xiii), to solve the problem in Echinopsis, to dust off, in his words, the "old favorites" (and now paraphyletics) Echinopsis, Lobivia and Trichocereus, together with the above mentioned genera of Schlumpberger, in addition to adding confusion to confusion, fall under the second hypothesis. (Quoted from Anceschi & Magli 2021, 47-49)
