Margyricarpus pinnatus (Lam.) Kuntze (1898: 77)

Funez, Luís A., Hassemer, Gustavo, Peroni, Nivaldo & Drechsler-Santos, Elisandro R., 2021, Two new species of Margyricarpus (Rosaceae, Sanguisorbeae) from high-elevation grasslands in southern Brazil, and other notes on the genus Margyricarpus, Phytotaxa 496 (3), pp. 281-293 : 288-291

2.2. Margyricarpus pinnatus (Lam.) Kuntze (1898: 77)

≡ Empetrum pinnatum de Lamarck (1785: 567) ≡ Margyricarpus laevis Willdenow (1801: 437) , nom. superfl. et illeg. (Art. 52 of the Code) Type: — URUGUAY. MONTEVIDEO: dans le sable de la plage de Montevideo, May 1767, P. Commerson 135 (lectotype [designated here]

P barcode P00162094! [Image available at: https://science.mnhn.fr/institution/mnhn/collection/p/item/p00162094]; isolectotypes P

barcode P00162095!, P barcode P01819228!).

= Margyricarpus setosus Ruiz & Pavón (1794: 28)

Type: — PERU. S.d., J. A. Pavón s.n. (lectotype [designated here] MA-812047! [Image available at: https://www.gbif.org/ occurrence/1936223040]); isolectotype BM barcode BM000602016 !).

= Margyricarpus imberbis Presl (1849: 200) , syn. nov.

Type: — PERU. S.d., T. P. X. Haenke s.n. (lectotype [designated here] PRC-455026! [Image available at: https://herbarium.univie.ac.at/ database/detail.php? ID =491000]).

= Margyricarpus patagonicus Spegazzini (1897: 513) , syn. nov.

≡ Margyricarpus setosus var. patagonicus (Speg.) Spegazzini (1902: 282) .

Type: — ARGENTINA . SANTA CRUZ. Río Santa Cruz , 4 August 1897, C. L . Spegazzini s.n. (lectotype [designated here] LP-15616 barcode 005583! [ Figure 6 ]; isolectotype LP-15615 barcode LP 005584 !) .

Diagnosis: —Ovary unicarpellate; hypanthium glabrous; endocarp with thorny projections.

Distribution: —Widely distributed throughout South America. This species occurs from Ecuador to Argentina along the Andean Cordilleras. Occurs in Chaco region, in Paraguay, and in the Pampas in southern Rio Grande do Sul (southern Brazil), eastern and Patagonian Argentina and Uruguay ( Zardini 1971, Reitz 1996, Steibel & Troiani 2000, Arroyo et al. 2001, Alonso Paz & Bassagoda 2003, Lueber & Muñoz-Schick 2005, Marticorena 2011, Hauenstein 2012). This species can be found on high altitude grasslands, in Atlantic Forest formation in Rio Grande do Sul, Santa Catarina, Paraná, São Paulo, Rio de Janeiro and Minas Gerais states, in South and Southeast regions of Brazil. Additionally, M. pinnatus is common in littoral dunes in Rio Grande do Sul, Santa Catarina states ( Brazil) and Uruguay.

Habitat: —This species is strongly related to harsh environments, with constant presence of fire, ice, salt or deficit hydric, growing on rocky outcrops, high altitude grasslands, dry soils and sand dunes on full sun exposure.

Photographs of living specimens: — Figure 7 .

Nomenclatural notes: — The protologue of Empetrum pinnatum ( de Lamarck 1785: 567) gave the following information regarding gatherings: “ Ce fous-arbrifleau a éte trouvé Monte-Video, dans des lieux fablonneux, par M. Commeson, & au Pérou, par M. Joseph de Jussieu ”. We could locate three specimens (syntypes, according to Art. 9.6): two collections from Montevideo, Uruguay “ dans le sable de la plage de Montevideo ”, May 1767, P. Commerson 135 ( P barcode P00162094 and P barcode P01819228 ) and one from Peru, ( A. L. de Jussieu s.n., P barcode P00162095 ). We designate here the most complete specimen among the syntypes , viz. P barcode P00162094 , as lectotype .

Margyricarpus laevis is a new name proposed by Carl Ludwig Willdenow (1765–1812) for Empetrum pinnatum . According to Art. 52 of the Code it is a superfluous and illegitimate name.

The information provided in the protologue of M. setosus ( Ruiz & Pavón 1794: 28) is very limited. The most important information for typification purposes was a list of localities: “ Habitat in collibus aridis et frigidis locis Provinciarum Tarmae, Xauxae, Huamalies, Huarocherí, Conchucos, arenosique Regni Chilensis ”. According to this information, we were able to find two specimens (syntypes, according to Art. 9.6): BM barcode BM000602016 and MA-812047. We designate here the most complete specimen, viz. MA-812047, as lectotype. We also located a specimen (viz. BC-873010) that was collected by Pavón in 1782, which we do not think should be considered original material, because it was collected in Concepción ( Chile), a locality not mentioned in the protologue .

The protologue of M. imberbis ( Presl 1849: 200) provided the following information: “ M. setosus Bertero herb n. 1478 – Habitat in Peruvia (Haenke), in pascuis saxois sterilibus insulae Juan-Fernandez (Bertero) ”. We found two specimens that match the information provided in the protologue, both clearly labelled by Carl Borijov.Presl (1794– 1852) as types of M. imberbis . With our study of these specimens we found out that the syntypes of M. imberbis belong to two distinct taxa: M. pinnatus (the specimen PRC-455026) and M. digynus (the specimen PRC-455027). We should remark that the morphological information provided in the protologue does not allow distinguishing between these two species. Here we designate as lectotype the specimen that belongs to M. pinnatus (i.e., the specimen PRC-455026). The reason for our choice is because the Peruvian element was mentioned first in the protologue, and also because the name M. imberbis is older than M. digynus , which is a currently-accepted name with an unequivocal identity. Therefore, the option for a different lectotypification of M. imberbis would be disadvantageous to nomenclatural stability.

The protologue of M. patagonicus ( Spegazzini 1897: 513) provided the following information: “ Hab. in planitie glareosa siccissima prope Santa Cruz, anno 1882, ( C. S.) et prope Golfo de San Jorge anno 1896 ( C. S.) ” We could locate two syntypes (Art. 9.6 of the Code ): LP barcode LP 005583 and LP barcode LP 005584 . We designate here the most complete specimen (viz. LP-15616 barcode 005583) as lectotype of this name .

In the protologue of M.patagonicus, Spegazzini(1897:513) explicitly pointed that this plant belongs to Tetraglochin by the diagnosis and description he provided for the species: “ fructus glabri ochroleuci coriacei sicci, acuati, postice longe attenuato cuneati trigoni, angulis acutis non v. vix subalatis, non v. minute et vix 3-4 subdenticulatis, faciebus inter angulos planis v. convexulis , laevibus v. rugulosis ”. Nevertheless, in analysing the two syntypes of M. patagonicus , viz. the specimens LP barcode LP005583 and LP barcode LP005584 , we concluded that all these specimens belong to M. pinnatus . Therefore, we propose here the synonymisation of M. patagonicus under M. pinnatus .

Taxonomic notes: — Margyricarpus pinnatus as currently circumscribed is considered as a widely distributed and polymorphic species. However, this circumscription of M. pinnatus is most probably a species complex, and probably includes several narrowly endemic and endangered species concealed within this large circumscription. The main problem to analysis and delimiting the species on M. pinnatus complex is to access the specimens on its very wide distribution range, this would imply a very high cost and that we cannot afford to this moment. We studied the holotype of M. pinnatus , from Uruguay, which matches the morphologic characteristics with the specimens we found in southern Brazil, except for the two new species that we are describing here.

To avoid the possibility that M. microcarpus and M. lanatus would be later synonyms of any already existing name, we carefully checked all the names in the synonymy of M. pinnatus , and could ascertain that none of these names refer to the two entities that we describe as new species in this work.

Figures

FIGURE 6. Lectotype of Margyricarpus patagonicus (C.L. Spegazzini s.n., LP barcode 005583). Copyright: Museo de La Plata.

FIGURE 7. Field photographs of Margyricarpus pinnatus. A. Detail of the dehydrated fruits, showing the endocarp sculpture. B. Detail of a fruit, showing the fleshy white hypanthium. C. Habit.