(2847) Proposal to conserve the name Anthurium microspadix against A. porrectum (Araceae)

Abstract

(2847) Anthurium microspadix Schott in Oesterr. Bot. Z. 8: 180. Jun 1858 [Angiosp.: Ar.], nom. cons. prop. Neotypus (hic designatus): Costa Rica, Cartago, Cantón de Jiménez, Selva, Tausito, 18 Jan 1996, Cascante & al. 924 (MO No. 4961354, barcode MO-928001; isoneotypus: CR). (=) Anthurium porrectum Schott in Oesterr. Bot. Z. 8: 180. Jun 1858, nom. rej. prop. Lectotypus (vide Croat & Baker in Brenesia 16(Supl. 1): 61. Dec 1979): Costa Rica, Desengaño, 8000’, 9 Mai 1857, Wendland 841 (GOET barcode GOET000236). Anthurium microspadix Schott was described by Heinrich Wilhelm Schott in June 1858 (in Oesterr. Bot. Z. 8: 180. 1858) based on material that had been collected by Danish botanist Anders Oersted “bei Naranjo in Costa-rica.” [In Schott (l.c. 1858: 179), the generic name was printed as ‘Anthaeria’, but as all the species described under this are included by Schott (Prodr. Syst. Aroid.: 583–585. 1860) in Anthurium, ‘Anthaeria’ would appear to be just a typographical error.] In his lone subsequent account of A. microspadix, Schott (l.c. 1860: 444) added only the phrase “vid. s. in Herbar. Oersted” (i.e., “I have seen it in a dried state in Oersted's herbarium”). Later authors have provided negligible or questionable additional details. Engler (in Candolle & Candolle, Monogr. Phan. 2: 112. 1879) located Oersted's specimen more precisely at C in citing “Oerstedt in h. Hafn.” Some years later, Engler (in Bot. Jahrb. Syst. 25: 382. 1898) only confused matters by apparently conflating two distinct Costa Rican localities named “Naranjo” in citing “in silvis ad flumen Rio Narango [sic], alt. 200–250 m (Oerstedt, Tonduz in Pitt. et Dur. Pl. costar. n. 7524. — Florif. m. Mart. 1893).” Oersted (who died in 1872) could have had no involvement with that cited collection, and is not known to have visited its Pacific lowland locality, in Puntarenas Province along the Río Naranjo (near Puerto Quepos); the “Naranjo” of Oersted (and other early collectors) was located at or very near the site of the town known presently (and for at least the past 131 years) as Juan Viñas (Tonduz in Bull. Herb. Boissier 3: 458. 1895), on the Atlantic slope of Costa Rica at about 1242 m elevation in Cartago Province (in a life zone much more favorable for A. microspadix). Even though Tonduz 7524 (CR) does indeed appear to represent A. microspadix (B.E. Hammel, pers. comm.), it clearly does not qualify as original material. No indications that original material has been seen have been detected in works published during the past century. Standley had occasion to use the name A. microspadix at least twice (in Publ. Field Mus. Nat. Hist., Bot. Ser. 18(1): 134. 1937, in Ann. Missouri Bot. Gard. 31: 21. 1944), but did not cite a type in either publication. Croat & Baker (in Brenesia 16(Supl. 1): 61. 1979) cited the type as “Oersted s.n.”, from “near Naranjo”, with the qualification “Type: Not found”, and Croat has adhered to that formula in his subsequent revisonary works (Croat in Ann. Missouri Bot. Gard. 70: 325. 1983, in Monogr. Syst. Bot. Missouri Bot. Gard. 14: 140. 1986; Croat & al. in Aroideana 32: 79. 2009), as have some other authors (e.g., Espejo Serna & López-Ferrari, Monocot. Mex. Sin. Florist. 2: 15. 1993). It is evident that no original material of A. microspadix has been seen or located (by published authors) since at least the time of Engler. Riedl & Riedl-Dorn (in Taxon 37: 846–854. 1986) listed A. microspadix among the species that “were present in Schott's herbarium in Vienna, but no longer exist there”, indicating that just one sheet of A. microspadix was involved. No specimens conceivably representing original material of A. microspadix are manifest in the JSTOR Global Plants Database (accessed 11 Oct 2021). It thus seems highly likely that Oersted's original collection of A. microspadix from Naranjo was destroyed at W during World War II. A drawing (No. 322) presumably depicting that specimen can be found among Schott's “icones” and has been photographed (N.Y.B.G. Neg. No. N.S. 3812) and distributed to various herbaria (e.g., MO-2484620); however, the notion that Schott's undated and unpublished illustrations constitute original material is conjectural (see, e.g., Grayum in Syst. Bot. Monogr. 47: 4–5. 1996). In the absence of any elements identifiable unequivocally as original material, neotypification is the only option, but I can find no evidence that the name A. microspadix has ever been effectively neotypified. Therefore, neotypification on an exemplary modern collection is effected above. I have chosen a specimen from Cartago Province, relatively near the original type locality (which is now destitute of natural vegetation), that is duplicated in at least one Costa Rican herbarium and matches well both the protologue and the drawing of the lost holotype, especially in having subcordate-based leaves and a very small (shorter than the spathe) flowering spadix. The names Anthurium microspadix Schott, A. porrectum Schott, and A. tapinostachyum Schott, all based on Costa Rican material and published in the same paper (indeed, on the same page), have been treated since at least 1979 (Croat & Baker, l.c.) as applying to a single species, and are the three oldest names applicable to that species. The Code (ICN Art. 11.5; Turland & al. in Regnum Veg. 159. 2018) specifies that, whenever “a choice is possible beetween legitimate names of equal priority at the corresponding rank, […] the first such choice to be effectively published […] establishes the priority of the chosen name […] over the other competing name(s) […]”. The earliest effectively published choice involving the three aforementioned names was certainly that of Engler (in Martius, Fl. Bras. 3(2): 54–55. 1878), who accepted the names A. porrectum and A. tapinostachyum, while citing A. microspadix as a synonym of the former. This taxonomic view was reiterated the following year by Engler (l.c. 1879: 112–115), but with A. microspadix regaining a modicum of taxonomic recognition as A. porrectum var. microspadix (Schott) Engl. Two decades later, Engler (l.c. 1898) changed his tune, restoring A. microspadix to species rank, with A. tapinostachyum as a synonym, while continuing to accept A. porrectum as a separate species. The same taxonomy was employed in Engler's partial treatment of Araceae for Henri Pittier's Primitiae florae Costaricensis (in Anales Inst. Fís.-Geogr. Mus. Nac. Costa Rica 9: 204–205. 1898) (though A. tapinostachyum was not mentioned there at all) and in his Das Pflanzenreich monograph of Anthurium (Engler, Pflanzenr. IV. 23B (Heft 21): 106–109. 1905), both of which would remain highly influential well into the 20th century. The foregoing paragraph makes it clear that the priority of Anthurium microspadix with respect to A. porrectum was first established, in favor of the latter, by Engler (l.c. 1878), and that of A. microspadix with respect to A. tapinostachyum in favor of the former by Engler (l.c. 1898). Although it may be impossible to prove a negative hypothesis, it is highly unlikely that anyone else had addressed these names previously, because few if any authors other than Engler and Schott (who died in 1865) were working on New World Araceae during the second half of the 19th century. It seems that the priority of A. porrectum with respect to A. tapinostachyum has never been established, but that point is moot for the purpose at hand. According to precedent, the correct name for a species that includes the types of all three names must be A. porrectum: A. porrectum has priority over A. microspadix, while the name A. tapinostachyum cannot be used for any species that also includes the type of A. microspadix (which has priority over A. tapinostachyum). The actual usage of the names Anthurium microspadix, A. porrectum, and A. tapinostachyum has followed a slightly different course. As far as I can determine, the last-mentioned name was never again used for an accepted species after being synonymized by Engler in 1898. Few if any botanists specialized on Araceae were working in Neotropical regions during the first half of the 20th century. As a result, the species diversity of Araceae in general was often underestimated, and there was a tendency (as in many plant families) to use different names, for the same species, in different countries. During this period, the only floristic work to have mentioned both A. microspadix and A. porrectum was, apparently, Paul Standley's “Flora of Costa Rica” (in Publ. Field Mus. Nat. Hist., Bot. Ser. 18: 134–135. 1937), which followed Engler in accepting both names for ostensibly distinct species. Another 32 years would pass before the two names (together with A. tapinostachyum) were applied (without comment) to a single species by Croat & Baker (l.c.), who mistakenly chose A. microspadix as the accepted name. [Croat & Baker (l.c.) also typified the synonyms of A. microspadix, considering that the Wendland specimen cited above was the holotype of A. porrectum. Because Schott also cited an Oersted collection in the protologue, this has been corrected to lectotype under Art. 9.10 of the ICN.] In the interim, the species in question had either been overlooked, or (perhaps) included under a misapplied name (e.g., Macbride in Publ. Field. Mus. Nat. Hist., Bot. Ser. 13(1): 428–486. 1936; Matuda in Anales Inst. Biol. Univ. Nac. México 25: 97–218. 1954), or else treated using a different name since synonymized under A. microspadix (e.g., Standley & Steyermark in Fieldiana, Bot. 24(1): 321. 1958; Bunting in Gentes Herb. 9: 290–382. 1965; and Molina in Ceiba 19: 23. 1975, all of which employed the name A. tuerckheimii Engl., based on a Guatemalan type). In his treatment of Araceae for the Flora of Panama, Standley (in Ann. Missouri Bot. Gard. 31: 20–22. 1944) used the name A. microspadix, but the only specimen cited thereunder actually corresponds to A. pallens Schott (according to a determination by T.B. Croat, 1975); all the specimens currently identified as A. microspadix were cited by Standley under A. gracilens Standl. (based on a Panamanian type, and now deemed synonymous with A. microspadix) or A. pallens. Similarly, Dodson & Gentry (in Selbyana 4: 52. 1978) used the name A. retusum Sodiro (based on an Ecuadorian type, and now considered a synonym of A. microspadix) for material currently determined (at MO) as A. microspadix. Since 1979 (Croat & Baker, l.c.), however, A. microspadix has been used consistently, to the exclusion of all acknowledged synonyms, in at least 20 major revisions, flora treatments, and checklists, e.g.: Croat (l.c. 1983, 1986), Balick & al. (in Mem. New York Bot. Gard. 85: 171. 2000), Croat & Stiebel (in Monogr. Syst. Bot. Missouri Bot. Gard. 85: 146. 2001), Govaerts & Frodin (World Checkl. Bibliogr. Araceae: 139–140. 2002), Grayum (in Monogr. Syst. Bot. Missouri Bot. Gard. 92: 91. 2003), Correa & al. (Cat. Pl. Vasc. Panamá: 111. 2004), and Galeano (in Bernal & al., Cat. Pl. Líquenes Colombia 1: 709–710. 2016). This proposal seeks to secure the name Anthurium microspadix for the species widely known as such for more than 40 years by conserving that name over the prior A. porrectum, which has been in disuse for an equivalent period. The species involved is relatively inconspicuous, by the standards of its genus, and has not been widely cultivated for ornamental purposes; it has no documented ethnobotanical or economic uses (see, e.g., Plowman in Econ. Bot. 23: 97–122. 1969), and has not been the subject of any significant ecological studies. That said, the species currently known as A. microspadix is one of the commonest, most widespread, and frequently collected members of its sizeable (ca. 1000 species) genus. It ranges from southern Mexico to Bolivia, mainly in montane habitats at 500–2950 m elevation, and because of its modest size and easy accessibility, is one of the more convenient species of Araceae to collect, press, and dry. The Tropicos database of the Missouri Botanical Garden (accessed 11 Oct 2021) includes 824 specimen records under A. microspadix, over its entire geographic range, compared to just 4 under A. porrectum; and for whatever it may be worth, a Google search (undertaken 30 Jul 2021) returned more than 16 times as many hits (3570, vs. 215) for A. microspadix than for A. porrectum. Should this proposal be rejected, the name A. microspadix would have to be replaced by A. porrectum, necessitating the re-annotation of many hundreds of specimens, in a wide range of herbaria, and engendering confusion in the taxonomic and floristic literature. MHG, https://orcid.org/0000-0002-9501-1161 I am grateful to Fred R. Barrie (MO) for his valuable insights during the preparation of this manuscript, and to Barry E. Hammel (MO) for consulting critical material in the CR herbarium. The submitted draft was much improved by the editorial corrections and suggestions of John McNeill and John Wiersema.