Centaurea valdemonensis Domina, Di Grist., Barone, 2022

Domina, Gianniantonio, Di Gristina, Emilio & Barone, Giulio, 2022, A new species within the Centaurea busambarensis complex (Asteraceae, Cardueae) from Sicily, Biodiversity Data Journal 10, pp. 91505-91505 : 91505

Centaurea valdemonensis Domina, Di Grist., Barone sp. nov.

Materials

Type status: Holotype. Occurrence: occurrenceID: 650C4F94-5407-55F7-BB94-EB377974DB39; recordedBy: Domina G., Di Gristina E.; Taxon: scientificName: Centaurea valdemonensis Domina, Di Grist., Barone; Location: country: Italy; stateProvince: Sicily; locality: Nebrodi Mountains, Rocche del Crasto ; verbatimElevation: 1280 m a.s.l.; decimalLatitude: 38.013182; decimalLongitude: 14.737629; geodeticDatum: WGS84; Event: year: 2022; month: 6; day: 24; habitat: crevices of limestone rocks; Record Level: institutionCode: PAL109753; basisOfRecord: PreservedSpecimen Type status: Isotype. Occurrence: occurrenceID: B5EFFA30-8640-53BA-978E-BF71E39C29A2; recordedBy: Domina G., Di Gristina E.; Taxon: scientificName: Centaurea valdemonensis Domina, Di Grist., Barone; Location: country: Italy; stateProvince: Sicily; locality: Nebrodi Mountains, Rocche del Crasto , crevices of limestone rocks ; verbatimElevation: 1280 m a.s.l.; decimalLatitude: 38.013182; decimalLongitude: 14.737629; geodeticDatum: WGS84; Event: year: 2022; month: 6; day: 24; habitat: crevices of limestone rocks; Record Level: institutionCode: PAL-Gr; basisOfRecord: PreservedSpecimen Type status: Isotype. Occurrence: occurrenceID: B0670CE1-DD18-5910-98BD-A734E50B28E2; recordedBy: Domina G., Di Gristina E.; Taxon: scientificName: Centaurea valdemonensis Domina, Di Grist., Barone; Location: country: Italy; stateProvince: Sicily; locality: Nebrodi Mountains, Rocche del Crasto , crevices of limestone rocks ; verbatimElevation: 1280 m a.s.l.; decimalLatitude: 38.013182; decimalLongitude: 14.737629; geodeticDatum: WGS84; Event: year: 2022; month: 6; day: 24; habitat: crevices of limestone rocks; Record Level: institutionCode: SAF100085; basisOfRecord: PreservedSpecimen

Description

Perennial herb up to 50 cm, rosette-forming. Stem erect, white tomentose, with few branches above. Rosette leaves lyrate, 1-2 pinnatisect, white tomentose to arachnoid-hairy 9-30 cm long, 3-12 cm large. Cauline leaves 1-2 pinnatisect, with sinuate margins, white tomentose, 4-7 mm long, 3-4 mm large. Branch leaves entire, 5-10 mm × 3-6 mm. Capitula in clusters of 2-7. Peduncles 1-3 mm wide, with sparse leaves. Involucre ovoid, 11-15 × 11-16 mm; bracts ovate-lanceolate, glabrescent to arachnoid-hairy, with 7-9 nerves on the back. Appendages dark brown to black, shortly decurrent at the base, fimbriate. Appendages below the fimbria, with a 1-1.5 mm wide margin. Fimbriae 6-9 on each side, 1-2 mm long. Florets pink-violet, 12-18 mm long. Achenes light brown, 3.8-4.7 mm long, 1.5-2.1 mm wide. Pappus white, 1.5-2.0 mm long. (Fig. 6 ).

Diagnosis

Herba perennis, tomentosa, foliis 1-2 pinnatipartitis, incanis. Corymbus 2-7 capitulis; involucra ovata, 11-15 × 11-16 mm. Appendices fuscae vel nigrae; fimbriae 6-9 utroque latere, 1-2 mm longae. Flosculi roseo-lilacini; achenia luteo-brunnea 3.8-4.7 × 1.5-2.1 mm; pappus albus 1.5-2 mm longus.

Etymology

The specific epithet refers to the "Valdemone Mountains", the name used since Middle Ages up to the 19th Century for the NE Sicilian range where the species here described was found.

Distribution

As known so far, Centaurea valdemonensis occurs in a single population northeast Sicily, on the Nebrodi Mountains; but it is not excluded that the mountain complex may host other subpopulations.

Ecology

The known locality is found between 1,200 and 1,300 m a.s.l. Like other representatives of the Centaurea busambarensis complex, C. valdemonensis occurs on carbonate rocky habitat, with Anthemis cupaniana Nyman, Athamanta sicula L., Hyoseris radiata L., Saxifraga granulata L., Sedum hispanicum L., Senecio balansae Boiss. & Reut., Teucrium chamaedrys L. subsp. chamaedrys , Teucrium flavum L. subsp. flavum etc.

Conservation

The population of Rocche del Crasto includes about 300 mature individuals and extends for about 7000 m2. The plants that grow in the lower part of the cliff are subject to cow grazing.

Biology

Hemicryptophyte rosulate with chasmophyte habit, flowering and fruiting from June to August.

Taxon discussion

The new species here described is well differentiated from the other species of the Centaurea busambarensis complex (Table 2 ). The most related species is C. busambarensis . The two species are, anyway, easily distinguishable by the shape of rosette leaves 1-2 pinnatisect with apical lobe slashed in C. valdemonensis and one pinnatisect with apical lobe almost entire in C. busambarensis (Fig. 7 ). In addition, the appendage of the median capitula bracts is shorter (2 mm) with shorter fimbriae (1-2 mm long) in C. valdemonensis than in C. busambarensis (3 mm long, with fimbriae 2.5-3 mm long) (Fig. 7 ). The shape of the rosette leaves is similar, in some ways, to that of C. tauromenitana , endemic to the east coast of Sicily (0-600 m a.s.l.), but not belonging to the C. busambarensis complex by having the yellow flowers in very large capitula with brown appendages and glabrescent habitus.

Figures

Figure 6. Centaurea valdemonensis Domina et al. a habit; b rosette leaf; c stem leaf; d branch leaves; e capitulum; f phyllary; g cypsela (drawn by G. Domina from the original material).

Figure 7. Capitulum in Centaurea valdemonensis (a) and C. busambarensis (b); rosette leaves in C. valdemonensis (c) and C. busambarensis (d).