ARTÍCULO

On the identity of two hybrids in the genus Brachypodium (Brachypodieae, Poaceae): typification of the names B. × cugnacii and B. × paui

PEDRO PABLO FERRER-GALLEGO¹ & JAVIER FABADO²

¹ Servicio de Vida Silvestre y Red Natura 2000, Centro para la Investigación y la Experimentación Forestal de la Generalitat Valenciana (CIEF), av. Comarques del País Valencià, 114, ES-46930 Quart de Poblet, Valencia, España
² Jardín Botánico, Universitat de València, c. Quart 80, ES-46008 Valencia, España

ORCID iD. P. P. FERRER-GALLEGO: https://orcid.org/0000-0001-7595-9302, J. FABADO: https://orcid.org/0000-0001-9461-3008

Author for correspondence: P. P. Ferrer-Gallego (flora.cief@gva.es)

Editor: N. Nualart

ABSTRACT
On the identity of two hybrids in the genus Brachypodium (Brachypodieae, Poaceae): typification of the names B. ×cugnacii and B. ×paui.— The typification of the names Brachypodium ×cugnacii and B. ×paui (Brachypodieae, Poaceae) is discussed. All relevant sources, as well as specimens, illustrations, and references cited in the protologues are carefully examined for the purpose to fix the application of the names. The two names above mentioned are lectotypified using specimens preserved at P and BC herbaria, respectively. Finally, a comment on the nomenclatural type of Brachypodium retusum is reported.
KEY WORDS: Bromus retusus; Gramineae; Iberian Peninsula; lectotype; nomenclature; Sennen.

RESUMEN
Sobre la identidad de dos híbridos del género brachypodium (brachypodieae, poaceae): tipificación de los nombres B. ×cugnacii y B. ×paui.— Se discute la tipificación de los nombres Brachypodium ×cugnacii y B. ×paui (Brachypodieae, Poaceae). Todas las fuentes de información, como son los especímenes de herbario, ilustraciones y referencias relevantes citadas en los protólogos, se han evaluado cuidadosamente con el fin de fijar la aplicación precisa de los nombres. Los nombres mencionados se han lectotipificado utilizando especímenes conservados en los herbarios P y BC, respectivamente. Finalmente, se aporta un comentario sobre el tipo nomenclatural de Brachypodium retusum.
PALABRAS CLAVE: Bromus retusus; Gramineae; lectotipo; nomenclatura; Península Ibérica; Sennen.

CONTENIDOS

INTRODUCTIONTop

Brachypodium Palisot de Beauvois (1812Palisot de Beauvois, A.-M. F.-J. 1812. Essai d’une nouvelle agrostographie; ou nouveaux genres des graminées; avec figures représentant les caractères de tous les genres. Imprimerie de Fain, Paris. https://doi.org/10.5962/bhl.title.474 : 100, 155) (Brachypodieae, Pooideae) is a genus of temperate grasses distributed worldwide (Smith, 1980Smith, P. M. 1980. Brachypodium Beauv. In: Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A. (Eds.) Flora Europaea 5. Cambridge University Press, Cambridge: 189–190.; Schippmann, 1991Schippmann, U. 1991. Revision der europäischen Arten der Gattung Brachypodium Palisot de Beauvois (Poaceae). Boissiera 45: 1–249.; Catalán & Olmstead, 2000Catalán, P. & Olmstead, R. G. 2000. Phylogenetic reconstruction of the genus Brachypodium P. Beauv. (Poaceae) from combined sequences of chloroplast ndhF gene and nuclear ITS. Plant Systematics and Evolution 200: 1–19. https://doi.org/10.1007/BF00985367; Piep, 2007Piep, M. B. 2007. Brachypodium. In: Barkworth M. E., Capels, K. M., Long, S. & Anderton, L. K. (Eds.), Flora of North America North of Mexico 24. Oxford University Press, New York-Oxford: 187–192.) and comprises 15–20 species (Schippmann, 1991Schippmann, U. 1991. Revision der europäischen Arten der Gattung Brachypodium Palisot de Beauvois (Poaceae). Boissiera 45: 1–249.; Catalán et al. 1995Catalán, P., Shi, Y., Armstrong, L., Draper, J. & Stace, C. A. 1995. Molecular phylogeny of the grass genus Brachypodium P. Beauv. based on RFLP and RAPD analysis. Botanical Journal of the Linnean Society 117: 263–280. https://doi.org/10.1111/j.1095-8339.1995.tb02590.x , 2012Catalán, P., Müller, J., Hasterok, R., Jenkins, G., Mur, L. A. J., Langdon, T., Betekhtin, A., Siwinkska, D., Pimentel, M. & López-Alvarez, D. 2012. Evolution and taxonomic split of the model grass Brachypodium distachyon. Annals of Botany 109(2): 385–405. https://doi.org/10.1093/aob/mcr294 ; 2015Catalán, P., López-Álvarez, D., Díaz-Pérez, A., Sancho, R. & López-Herránz, M. L. 2015. Phylogeny and evolution of the genus Brachypodium. In: Vogel, J. P. (Ed.), Genetics and Genomics of Brachypodium (Plant Genetics and Genomics: Crops and Models, 18). Springer, Cham: 9–38. https://doi.org/10.1007/7397_2015_17; Díaz-Pérez et al., 2018Díaz-Pérez, A., López-Álvarez, D., Sancho, R. & Catalán, P. 2018. Reconstructing the origins and the biogeography of species’ genomes in the highly reticulate allopolyploid-rich model grass genus Brachypodium using minimum evolution, coalescence and maximum likelihood approaches. Molecular Phylogenetics and Evolution 127: 256–271. https://doi.org/10.1016/j.ympev.2018.06.003 ; POWO, 2023POWO [Plants of the World Online] 2023. Retrieved January 29, 2023, from https://powo.science.kew.org ). The genus Brachypodium represents a model system that is advancing our knowledge of the biology of grasses in the postgenomics era (Draper et al., 2001Draper, J., Mur, L. A. J., Jenkins, G., Ghosh-Biswas, C., Bablak, P., Hasterok, R. & Routledge, A. P. M. 2001. Brachypodium distachyon. A new model system for functional genomics in grasses. Plant Physiology 127(4): 1539–1555. https://doi.org/10.1104/pp.010196; IBI, 2010IBI [International Brachypodium Initiative] 2010. Genome sequencing and analysis of the model grass Brachypodium distachyon. Nature 463(7282): 763–768. https://doi.org/10.1038/nature08747 ).

For the Iberian Peninsula, the most recent treatment of this genus has been generated by López González (2021López González, G. 2021. Brachypodium P. Beauv. In: Romero Zarco, C., Rico, E., Crespo, M. B., Devesa, J. A., Buira, T. & Aedo, C. (Eds.), Flora iberica 19(2). Real Jardín Botánico, CSIC, Madrid: 980–994.). This author recognized only a species in the Brachypodium distachyon (L.) P. Beauv. complex. However, Catalán et al. (2012Catalán, P., Müller, J., Hasterok, R., Jenkins, G., Mur, L. A. J., Langdon, T., Betekhtin, A., Siwinkska, D., Pimentel, M. & López-Alvarez, D. 2012. Evolution and taxonomic split of the model grass Brachypodium distachyon. Annals of Botany 109(2): 385–405. https://doi.org/10.1093/aob/mcr294 , 2016Catalán, P., López-Álvarez, D., Bellosta, C. & Villar, L. 2016. Updated taxonomic descriptions, iconography, and habitat preferences of Brachypodium distachyon, B. stacei, and B. hybridum (Poaceae). Anales del Jardín Botánico de Madrid 73(1): e028. https://doi.org/10.3989/ajbm.2428 ) and López-Álvarez et al. (2012López-Álvarez, D., López-Herranz, M. L., Betekhtin, A. & Catalán, P. 2012. A DNA barcoding method to discriminate between the model plant Brachypodium distachyon and its close relatives B. stacei and B. hybridum (Poaceae). PLoS One 7: e51058. https://doi.org/10.1371/journal.pone.0051058 , 2015López-Álvarez, D., Manzaneda, A. J., Rey, P. J., Giraldo, P., Benavente, E., Allainguillaume, J., Mur, L., Caicedo, A. L., Hazen, S. P., Breiman, A., Ezrati, S. & Catalán, P. 2015. Environmental niche variation and evolutionary diversification of the Brachypodium distachyon grass complex species in their native circum-Mediterranean range. American Journal of Botany 102: 1073–1088. https://doi.org/10.3732/ajb.1500128 , 2017López-Álvarez, D., Zubair, H., Beckmann, M., Draper, J. & Catalán, P. 2017. Diversity and association of phenotypic and metabolomic traits in the close model grasses Brachypodium distachyon, B. stacei and B. hybridum. Annals of Botany 119: 545–561. https://doi.org/10.1093/aob/mcw239 ) published a comprehensive treatment of this complex and recognized three species on the basis of morphological and genetic characters and geographic distribution: B. distachyon, B. hybridum Catalán, Joch. Müll, Hasterok & G. Jenkins, and B. stacei Catalán, Joch. Müll, L. A. J. Mur & T. Langdon.

Interspecific natural hybridization in Brachypodium via pollen flow was highlighted by Khan & Stace (1999Khan, M. A. & Stace, C. A. 1999. Breeding relationships in the genus Brachypodium (Poaceae: Pooideae). Nordic Journal of Botany 19: 257–269. https://doi.org/10.1111/j.1756-1051.1999.tb01108.x ). Brachypodium ×paui Sennen was described as a hybrid between B. retusum (Pers.) P. Beauv. and B. distachyon (see Sennen, 1911Sennen, F. 1911. Plantes d’Espagne: Notes et diagnoses. Bulletin de l’Académie Internationale de Géographie Botanique 21(259): 101–138. ).

Brachypodium retusum is a rhizomatous perennial C₃ grass that grows in dry grasslands, shrublands and open woodlands of the Mediterranean Basin, Arabian Peninsula, and Africa (Morocco, Algeria, Tunisia, and Egypt) (Smith, 1980Smith, P. M. 1980. Brachypodium Beauv. In: Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A. (Eds.) Flora Europaea 5. Cambridge University Press, Cambridge: 189–190.; Schippmann, 1991Schippmann, U. 1991. Revision der europäischen Arten der Gattung Brachypodium Palisot de Beauvois (Poaceae). Boissiera 45: 1–249.; Cope et al., 2007Cope, T. A., Knees, S. G. & Miller, A. G. 2007. Flora of the Arabian peninsula and Socotra 5(1). Edinburgh University Press, Edinburgh.; López González, 2021López González, G. 2021. Brachypodium P. Beauv. In: Romero Zarco, C., Rico, E., Crespo, M. B., Devesa, J. A., Buira, T. & Aedo, C. (Eds.), Flora iberica 19(2). Real Jardín Botánico, CSIC, Madrid: 980–994.; AFA, 2023AFA [African Plant Database] 2022. Brachypodium retusum (Pers.) P. Beauv. Retrieved October 15, 2022, from https://africanplantdatabase.ch/en/nomen/49881; POWO, 2023POWO [Plants of the World Online] 2023. Retrieved January 29, 2023, from https://powo.science.kew.org ). This species is a rhizomatous plant, with stems 15–50 cm, erect or geniculately ascending, slender, glabrous, leaves up to 10 cm, often less, acute, the cauline patent, distichous; raceme 4–9 cm, dense, stiffly erect, with 1–5(–9) spikelets; spikelets (12–)20–30 mm, linear, overlapping considerably, glabrous, glaucous, with (6–)10–15 florets, glumes acute; lemma 7–8 mm, ovate-lanceolate, abruptly narrowed to the apex; awn 2–4 mm, straight, sometimes absent on lower lemmas (Smith, 1980Smith, P. M. 1980. Brachypodium Beauv. In: Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A. (Eds.) Flora Europaea 5. Cambridge University Press, Cambridge: 189–190.; Schippmann, 1991Schippmann, U. 1991. Revision der europäischen Arten der Gattung Brachypodium Palisot de Beauvois (Poaceae). Boissiera 45: 1–249.; López González, 2021López González, G. 2021. Brachypodium P. Beauv. In: Romero Zarco, C., Rico, E., Crespo, M. B., Devesa, J. A., Buira, T. & Aedo, C. (Eds.), Flora iberica 19(2). Real Jardín Botánico, CSIC, Madrid: 980–994.).

Brachypodium distachyon is a grass species native to southern Europe, northern Africa and southwestern Asia east to India (Schippmann, 1991Schippmann, U. 1991. Revision der europäischen Arten der Gattung Brachypodium Palisot de Beauvois (Poaceae). Boissiera 45: 1–249.; POWO, 2023POWO [Plants of the World Online] 2023. Retrieved January 29, 2023, from https://powo.science.kew.org ). The close relationship of B. distachyon with economically important temperate cereals and forage grasses combined with many other favorable attributes, such as its very small nuclear genome, simple growth requirements, small size, and annual life cycle, prompted Draper et al. (2001Draper, J., Mur, L. A. J., Jenkins, G., Ghosh-Biswas, C., Bablak, P., Hasterok, R. & Routledge, A. P. M. 2001. Brachypodium distachyon. A new model system for functional genomics in grasses. Plant Physiology 127(4): 1539–1555. https://doi.org/10.1104/pp.010196) to propose it as a model organism (see IBI, 2010IBI [International Brachypodium Initiative] 2010. Genome sequencing and analysis of the model grass Brachypodium distachyon. Nature 463(7282): 763–768. https://doi.org/10.1038/nature08747 ). The name of B. distachyon is restricted to a stiffly erect annual plant up to (2–)6–15(–56) cm high, culm with (1–)3–4 nodes, leaves (1–)3–7(–8.5) cm × (0.25–) 1.5–2(–4) mm, short, bright green and (1–)2(–4) spikelets per panicle, spikelets (9.2–)14–15(–24) mm, and lemmas (5.2–)7–8(–11) mm, 7-veined, awned, with awn (5–)10–11(–15.2) mm. Brachypodium hybridum is an erect or spreading annual plant up to (3.5–)30–40(–78) cm high, culm with 3–7(–18) nodes, leaves 7–8(–16) cm × (0.7–)2–3(–4.3) mm, long, pale dark green and 3(–6) spikelets per panicle. Finally, B. stacei is an erect annual grass up to 44–76(–150) cm high, with (1–)4(–9) nodes, soft leaves, curled, patent, pale green, (1.6–) 7–8(–15.1) cm × (0.26–)2–3(–7) mm, and (1–)3–4(–5) spikelets per panicle (see Catalán et al., 2012Catalán, P., Müller, J., Hasterok, R., Jenkins, G., Mur, L. A. J., Langdon, T., Betekhtin, A., Siwinkska, D., Pimentel, M. & López-Alvarez, D. 2012. Evolution and taxonomic split of the model grass Brachypodium distachyon. Annals of Botany 109(2): 385–405. https://doi.org/10.1093/aob/mcr294 , 2015Catalán, P., López-Álvarez, D., Díaz-Pérez, A., Sancho, R. & López-Herránz, M. L. 2015. Phylogeny and evolution of the genus Brachypodium. In: Vogel, J. P. (Ed.), Genetics and Genomics of Brachypodium (Plant Genetics and Genomics: Crops and Models, 18). Springer, Cham: 9–38. https://doi.org/10.1007/7397_2015_17, 2016Catalán, P., López-Álvarez, D., Bellosta, C. & Villar, L. 2016. Updated taxonomic descriptions, iconography, and habitat preferences of Brachypodium distachyon, B. stacei, and B. hybridum (Poaceae). Anales del Jardín Botánico de Madrid 73(1): e028. https://doi.org/10.3989/ajbm.2428 ). From the material studied by Catalán et al. (2012Catalán, P., Müller, J., Hasterok, R., Jenkins, G., Mur, L. A. J., Langdon, T., Betekhtin, A., Siwinkska, D., Pimentel, M. & López-Alvarez, D. 2012. Evolution and taxonomic split of the model grass Brachypodium distachyon. Annals of Botany 109(2): 385–405. https://doi.org/10.1093/aob/mcr294 , 2016Catalán, P., López-Álvarez, D., Bellosta, C. & Villar, L. 2016. Updated taxonomic descriptions, iconography, and habitat preferences of Brachypodium distachyon, B. stacei, and B. hybridum (Poaceae). Anales del Jardín Botánico de Madrid 73(1): e028. https://doi.org/10.3989/ajbm.2428 ) and from the study of some herbarium sheets collected by Sennen from Llers (Girona, Spain) (see e.g., P03218688, P06768158) the parent of B. ×paui could very probably be B. hybridum.

On the other hand, Brachypodium ×cugnacii A. Camus was described as a hybrid between B. pinnatum (L.) P. Beauv. and B. sylvaticum (Huds.) P. Beauv. (see Camus, 1931Camus, A. 1931. Quelques hybrides des genres Cistus, Bromus et Brachypodium. Bulletin de la Société Botanique de France 78(1): 97–102. https://doi.org/10.1080/00378941.1931.10832870 ). Brachypodium sylvaticum reportedly produces natural hybrids with B. pinnatum in Europe (Long, 1989Long, G. M. 1989. Morphological and Physiological Variation in Brachypodium sylvaticum. University of Wales, College of Cardiff, Cardiff.), and synthetic hybrids with B. pinnatum and B. phoenicoides (L.) Roem. & Schult. are viable (Khan & Stace, 1999Khan, M. A. & Stace, C. A. 1999. Breeding relationships in the genus Brachypodium (Poaceae: Pooideae). Nordic Journal of Botany 19: 257–269. https://doi.org/10.1111/j.1756-1051.1999.tb01108.x ).

Brachypodium sylvaticum is a species common in Europe, but also extends into Asia and North Africa (Catalán & Olmstead, 2000Catalán, P. & Olmstead, R. G. 2000. Phylogenetic reconstruction of the genus Brachypodium P. Beauv. (Poaceae) from combined sequences of chloroplast ndhF gene and nuclear ITS. Plant Systematics and Evolution 200: 1–19. https://doi.org/10.1007/BF00985367; Catalán et al., 2015Catalán, P., López-Álvarez, D., Díaz-Pérez, A., Sancho, R. & López-Herránz, M. L. 2015. Phylogeny and evolution of the genus Brachypodium. In: Vogel, J. P. (Ed.), Genetics and Genomics of Brachypodium (Plant Genetics and Genomics: Crops and Models, 18). Springer, Cham: 9–38. https://doi.org/10.1007/7397_2015_17; Díaz-Pérez et al., 2018Díaz-Pérez, A., López-Álvarez, D., Sancho, R. & Catalán, P. 2018. Reconstructing the origins and the biogeography of species’ genomes in the highly reticulate allopolyploid-rich model grass genus Brachypodium using minimum evolution, coalescence and maximum likelihood approaches. Molecular Phylogenetics and Evolution 127: 256–271. https://doi.org/10.1016/j.ympev.2018.06.003 ). This species is shortly (or scarcely) rhizomatous, usually pendent at tip of raceme, leaves usually 6–10 mm wide, sheaths usually pubescent, sometimes glabrous, raceme with (3–)5–12 spikelets, lemmas 6–12 mm, with awn 7–15 mm.

Brachypodium pinnatum is a widespread species in temperate regions of the Northern Hemisphere, it is a thermophilous species but also grows in cool continental climates and reaches higher latitudinal limits in East-Central Asia than B. sylvaticum, which grows in areas with more oceanic climates (Tzvelev, 1976Tzvelev, N. N. 1976. Zlaki SSSR. Nauka Publishers, Leningrad.; Catalán et al., 2016Catalán, P., López-Álvarez, D., Bellosta, C. & Villar, L. 2016. Updated taxonomic descriptions, iconography, and habitat preferences of Brachypodium distachyon, B. stacei, and B. hybridum (Poaceae). Anales del Jardín Botánico de Madrid 73(1): e028. https://doi.org/10.3989/ajbm.2428 ). Brachypodium pinnatum typically grows in more open areas, such as calcareous grasslands. It is extensively rhizomatous, usually erect, leaves 3–6 mm wide, raceme with (3–)6–15 spikelets, lemmas 6–11 mm, often glabrous, with awn 1–5 mm (Tzvelev, 1976Tzvelev, N. N. 1976. Zlaki SSSR. Nauka Publishers, Leningrad.; López González, 2021López González, G. 2021. Brachypodium P. Beauv. In: Romero Zarco, C., Rico, E., Crespo, M. B., Devesa, J. A., Buira, T. & Aedo, C. (Eds.), Flora iberica 19(2). Real Jardín Botánico, CSIC, Madrid: 980–994.). It is morphologically similar to B. rupestre (Host) Roem. & Schult. which also apparently has the same cytotypes as its close congener (2n = 2x = 18; 2n = 4x = 28) (see Stace, 2019Stace, C. 2019. New Flora of the British Isles (4th ed.). Cambridge University Press, Cambridge.) and could also have been involved in the hybridization with B. sylvaticum.

The present paper is a further step of our contributions to Brachypodium nomenclature (see, e.g., Fabado & Ferrer-Gallego, 2021Fabado, J. & Ferrer-Gallego, P. P. 2021. Typification of four species names published by William Hudson. Kew Bulletin 76(1): 1–6. https://doi.org/10.1007/s12225-021-09932-9 ; Ferrer-Gallego & Martínez Labarga, 2022aFerrer-Gallego, P. P. & Martínez Labarga, J. M. 2022a. Typification of the name Brachypodium obtusifolium (Brachypodieae, Poaceae). Phytotaxa 555(3): 273–278. https://doi.org/10.11646/phytotaxa.555.3.7, bFerrer-Gallego, P. P. & Martínez Labarga, J. M. 2022b. (2896) Proposal to conserve the name Bromus retusus (Brachypodium retusum) against B. plukenetii (Brachypodieae, Gramineae). Taxon 71: 694–696. https://doi.org/10.1002/tax.12749 ), the purpose of this paper is to contribute to the stability of the nomenclature of B. ×paui and B. ×cugnacii through the lectotypification of each of these two names.

MATERIAL AND METHODSTop

This work is based on the analysis of protologues, examination of relevant literature and study of the specimens conserved in the herbaria B, BC, BCN, DR, FR, MA, MPU, P, US, and VAL (acronyms follow Thiers, 2023Thiers, B. 2023. Index Herbariorum: a global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. Retrieved January 18, 2022, from: http://sweetgum.nybg.org/science/ih ). The identity of the designated types has been verified with the current use of their respective names. The typified names are arranged in alphabetic order, followed by their homotypic synonyms (indicated with the symbol “≡”). The names in current use are indicated in bold italics typeface.

RESULTS AND DISCUSSIONTop

Brachypodium ×cugnacii

The protologue of Brachypodium ×cugnacii (Camus, 1931Camus, A. 1931. Quelques hybrides des genres Cistus, Bromus et Brachypodium. Bulletin de la Société Botanique de France 78(1): 97–102. https://doi.org/10.1080/00378941.1931.10832870 ) includes the name “× Brachypodium Cugnacii A. Camus” and the hybrid formula “B. pinnatum P.B. × [Brachypodium] silvaticum R. et S. var. villosum Lej. et Court.”, and a complete diagnosis followed by the geographical provenance and gathering “Seìne-et-Oìse: Verrières (A. de Cugnac, 1930)”. This citation represents a syntype according to the Art. 9.6 of Shenzhen Code (hereafter as “ICN”; Turland et al., 2018Turland, N. J., Wiersema, J. H., Barrie, F. R., Greuter, W., Hawksworth, D. L., Herendeen, P. S., Knapp, S., Kusber, W.-H., Li, D.-Z., Marhold, K., May, T. W., McNeill, J., Monro, A. M., Prado, J., Price, M. J. & Smith, G. F. (Eds.) 2018. International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) (Regnum Vegetabile, 159). Koeltz Botanical Books, Glashütten. https://doi.org/10.12705/Code.2018 ). The protologue also includes a diagnosis and a table with several features to distinguish this hybrid and their parents.

Saint-Yves (1934Saint-Yves, A. 1934. Contribution à l’étude des Brachypodium (Europe et région méditerranéenne). Candollea 5: 427–493.: 435) synonymized the name Brachypodium ×cugnacii with B. pinnatum var. glaucovirens (this taxon is currently recognized as an independent species by several authors, see e.g., Catalán et al., 2015Catalán, P., López-Álvarez, D., Díaz-Pérez, A., Sancho, R. & López-Herránz, M. L. 2015. Phylogeny and evolution of the genus Brachypodium. In: Vogel, J. P. (Ed.), Genetics and Genomics of Brachypodium (Plant Genetics and Genomics: Crops and Models, 18). Springer, Cham: 9–38. https://doi.org/10.1007/7397_2015_17; POWO, 2023POWO [Plants of the World Online] 2023. Retrieved January 29, 2023, from https://powo.science.kew.org ). Schippmann (1991Schippmann, U. 1991. Revision der europäischen Arten der Gattung Brachypodium Palisot de Beauvois (Poaceae). Boissiera 45: 1–249.) treated B. ×cugnacii as a synonym of B. sylvaticum subsp. sylvaticum, and reported “typum non vidi”.

We have found two specimens at P (P03471271 and P03628878) for Brachypodium ×cugnacii. P03471271 is part of the original material, bearing a plant, with leaves and spikelets, and an original label handwritten by A. Camus annotated as “Herbier E. G. Camus & A. Camus / × Brachypodium Cugnacii A. Camus / B. pinnatum × silvaticum inter parentes / Seìne-et-Oìse: Verrières / 1930 / Legit de Cugnac / A. Camus” (Fig. 1). P03628878 bears a complete specimen, with leaves and flowers, and a handwritten label annotated as “× Brachypodium Cugnacii // S-et-O: Verrières / 7-VII-1931 / R. de Cugnac”. Since the year of collection (1931Camus, A. 1931. Quelques hybrides des genres Cistus, Bromus et Brachypodium. Bulletin de la Société Botanique de France 78(1): 97–102. https://doi.org/10.1080/00378941.1931.10832870 ) is not that reported in the protologue, P03628878 cannot be considered as part of the original material for B. ×cugnacii. As a consequence, P03471271 is here designated as the lectotype for the name B. ×cugnacii. This specimen and the rest of the material match the traditional concept and current use of the name (Camus, 1931Camus, A. 1931. Quelques hybrides des genres Cistus, Bromus et Brachypodium. Bulletin de la Société Botanique de France 78(1): 97–102. https://doi.org/10.1080/00378941.1931.10832870 ; López González, 2021López González, G. 2021. Brachypodium P. Beauv. In: Romero Zarco, C., Rico, E., Crespo, M. B., Devesa, J. A., Buira, T. & Aedo, C. (Eds.), Flora iberica 19(2). Real Jardín Botánico, CSIC, Madrid: 980–994.).

Brachypodium ×cugnacii A. Camus, Bull. Soc. Bot. France 78: 100. 1931 [= B. pinnatum (or cf. B. rupestre) × B. sylvaticum]

Lectotype (designated here): [France] Seìne-et-Oìse: Verrières, 1930, Cugnac s.n. (P03471271 [photo!]; Fig. 1).

Figure 1. Lectotype of Brachypodium ×cugnacii Camus (P03471271). Image courtesy of the herbarium P, reproduced with permission. [View full size] [Descargar tamaño completo]

Brachypodium ×paui

Sennen’s protologue (1911Sennen, F. 1911. Plantes d’Espagne: Notes et diagnoses. Bulletin de l’Académie Internationale de Géographie Botanique 21(259): 101–138. : 133) of Brachypodium ×paui (a taxon numbered with “409”) includes the hybrid formula “(B. ramosum × distachyon)?” followed by a complete diagnosis and the geographical provenances “Hab.: Garrigues et olivettes à Llers, Pont-de-Molins, Figueras; pentes du Tibidabo, près Barcelone; Benicarló à Bóbola!”.

Schippmann (1991Schippmann, U. 1991. Revision der europäischen Arten der Gattung Brachypodium Palisot de Beauvois (Poaceae). Boissiera 45: 1–249.) reported: “syntypi: “Plantes d’Espagne no. 409, Brachypodium Paui Sen.,? (B. ramosum + distachyon) Sen., Catalogne: Llers et Pont de Molins, olivettes, Juin 1907” (B!, FR!, LD!, M!); “Plantes d’Espagne no. 1046, Brachypodium Paui Sen., (B. ramosum + distachyos)? Sen., Catalogne: Barcelone, pentes du Tibidabo, VI.1910” (B!, FR!, LD!); specimen scheda manu scripta instructa: “Catalogne, Llers, olivettes, 19.VI.1905, F. Sennen” (B!); specimen scheda manu scripta instructa: “Catalonia, Figueras, champs, VI.[19]10, leg. Sennen” (LD!)”, and also commented about the material type and plant that “Das Typusmaterial ist in vielen Doubletten vorhanden. Einige der anatomisch und morphologisch untersuchten Pflanzen zeigen zwischen B. distachyon und B. retusum intermediäre Merkmale, bei anderen handelt es sich eindeutig um B. retusum” [The type material is available in many duplicates. Some of the anatomically and morphologically examined plants show intermediate characters between B. distachyon and B. retusum, others are clearly B. retusum] and “Sennen weist auf den Hybridcharakter dieses Taxons hin” [Sennen points out the hybrid character of this taxon]. Therefore, not all the specimens are syntypes.

We traced several original specimens of Brachypodium ×paui at B, BC, BCN, DR, FR, MA, MPU, P, US, and VAL herbaria. Among them, several (BC616312, BC616227, BC118838, BC71120, BC-Sennen [without number], BCN78982, DR061516, FR0031230, P02569267, P03139060, P03218686, P03218691, MA14348, MA14350, MA163576, MPU027893, MPU027892, VAL172458) are number with “409” as reported in the protologue, and collected in “Catalogne: Llers et Pont de Molins” in June 1907. These specimens can be considered as syntypes (Art. 9.6 of ICN) and therefore have a preference for lectotype designation according to Art. 9.12 of ICN. We designate as the lectotype of the name B. ×paui the specimen BC616227 (Fig. 2) since it bears a well-developed and complete plant which matches the traditional and current use and concept of the name B. ×paui (Sennen, 1911Sennen, F. 1911. Plantes d’Espagne: Notes et diagnoses. Bulletin de l’Académie Internationale de Géographie Botanique 21(259): 101–138. ; López González, 2021López González, G. 2021. Brachypodium P. Beauv. In: Romero Zarco, C., Rico, E., Crespo, M. B., Devesa, J. A., Buira, T. & Aedo, C. (Eds.), Flora iberica 19(2). Real Jardín Botánico, CSIC, Madrid: 980–994.): plants extensively branched, erect or geniculately ascending stems, glabrous; leaves up to 10 cm × 2–4 mm, with prominent spaced veins, flat, tough, becoming convolute when dry, acute, the cauline patent, distichous; ligule ca. 1 mm; raceme 4–9 cm, dense, stiffly erect, with 1–5(–7) spikelets; spikelets (12–)20–30 mm, linear, glabrous, glaucous, with (6–)10–15 florets; glumes acute, the lower 4–5 mm, the upper 6–7 mm; lemma 7–8 mm, ovate-lanceolate, abruptly narrowed to the apex.

Brachypodium ×paui Sennen, Bull. Géogr. Bot. 21(259): 133. 1911 [= B. distachyon complex (probably B. hybridum) × B. retusum]

≡ Brachypodium distachyon subsp. paui (Sennen) Malagarriga in Act. Phytotax. Barcinon. 18: 10. 1977

Lectotype (designated here): [Spain] Catalogne, Llers et Pont de Molins, June 1907, F. Sennen 409 (BC616227 [photo!]; Fig. 2). Isolectotypes: BC616312, BC118838, BC71120, BC-Sennen [without number], BCN 78982, DR061516, FR0031230, MA14348, MA14350, MA163576, P02569267, P03139060, P03218686, P03218691, MPU027893, MPU027892, VAL172458.

Figure 2. Lectotype of Brachypodium ×paui Sennen (BC616227). Image courtesy of the herbarium BC, reproduced with permission. [View full size] [Descargar tamaño completo]

Note on the nomenclatural type of Brachypodium retusum

The specimen now barcoded as L0043873 is the “holotype” of Bromus retusus Pers. according to Schippmann (1991Schippmann, U. 1991. Revision der europäischen Arten der Gattung Brachypodium Palisot de Beauvois (Poaceae). Boissiera 45: 1–249.: 106), who stated: “holotypus: “Bromus retusus Syn. plant. Enc. Botan., [...] Gallia Meridian.” (L!). - Die Herbarien BM, E, G, GOET, LD, LG und NY haben auf Anfrage mitgeteilt, daß sie kein Typus-Material dieser Art besitzen.” [Herbaria BM, E, G, GOET, LD, LG and NY have indicated upon request that they do not have any material of this type]. Thus, Schippmann unintentionally or “inadvertently” lectotypified the name. Moreover, we have also not found any further herbarium sheet with Persoon’s original material of B. retusus and, probably, the specimen at L is the only original material used by the author for the description of this plant. However, as we cannot exclude that there would be more than one specimen of this taxon in his collection, we consider the specimen L0043873 as the lectotype (corrected here according to Art. 9.10 of the ICN) of the name B. retusus, admitting that the specimen might well be the holotype.

Brachypodium retusum (Pers.) P. Beauv., Ess. Agrostogr.: 155, 156, 101. 1812

Lectotype (designated by Schippmann in Boissiera 45: 106. 1991, corrected here according to Art. 9.10 of the ICN): [France] in Gall. meridion, s.d., Persoon s.n., (L0043873; image available at https://bioportal.naturalis.nl/multimedia/L++0043873_0339368672/term=Brachypodium+retusum&from=38).

ACKNOWLEDGEMENTSTop

Thanks to Dr. Ginés López González and Dra. Pilar Catalán for their advice, assistance, and valuable comments that improved this work. Thanks to Neus Ibáñez (Institut Botànic de Barcelona) for his help in the study of the specimens in the herbarium BC.

REFERENCESTop