Vermilacinia breviloba Spjut & Sérus., 2020

Spjut, Richard, Simon, Antoine, Guissard, Martin, Magain, Nicolas & Serusiaux, Emmanuel, 2020, The fruticose genera in the Ramalinaceae (Ascomycota, Lecanoromycetes): their diversity and evolutionary history, MycoKeys 73, pp. 1-68 : 1

Vermilacinia breviloba Spjut & Sérus. sp. nov. Fig. 13A, B

Diagnosis.

Similar to V. robusta by the inflated branches and to V. polymorpha by the relatively short length of branches; differs by the honeycomb-like cortex or by the contorted lobes.

Type.

Mexico - Baja California, Pacific Coast ca. 100 km N of Guerrero Negro, just N of Punta San Rosalillita west of road to Punta Negra along track to Puerto San Andrés in a narrow arroyo leading to a tidal inlet (estuary); 28°42.62'N, 114°16.19'W, alt. 50 m, 26.01.2016, R. Spjut & E. Sérusiaux 17117 leg.; on steep north-facing rock ledges bordering south-side of tidal marsh, (LG! - holotype; BCMEX!, US!, hb. Spjut at World Botanical Associates! - isotypes) [TLC: salazinic acid, triterpene 3, zeorin, [-]-16α-hydroxykaurane; DNA: MN811491 (LSU), MN811295 (ITS), MN757090 (RPB1), MN757285 (RPB2), MN757407 (GDP), MN757544 (EF-1α)]

Description.

Thallus 1-1.5 (-2.5) cm high and 0.5-1 cm broad; basal branches 1-5 or rarely more, short cylindrical, teretiform or prismatic, 1-3 mm diam., loosely united at brownish base, ± erect, inflated, irregularly shriveled and contorted when dry, transversely segmented and ruptured when wet at ± regular intervals, terminally divided into short lobes with or without apothecia; terminal lobes often many and close together or fewer and spreading, 4-6 mm long, 2-4 mm diam. Cortex two-layered, 35-50 μm thick, outer thicker, melanized, externally pale olive green, with irregular reticulate cortical ridges, recessed-concave within ridges (honeycomb-like surface), occasionally plicate on inflated lobes. Medulla subfistulose, hyphae flexuous when wet, intertwining in a net arrangement, ± periclinal, frequently uniting into minute knots; Photobiont in small yellow green to green round colonies ± continuous around the perimeter of the medulla. Apothecia many, aggregate terminally on a primary branch, each subtended by a short stalk-like lobe partly deflated and constricted to junction with branch lobe, bowl-shaped when young, to 4 mm diam., lenticular with age; thalline margin thickened, incurved, entire or crenulate or incised, disc pale orange, concave; asci 8-spored; spores opaque, 1-septate, short ellipsoid, 6-7 × 4-5 μm. Pycnidia black, common on the upper half of branches in shallow concave depressions within cortical ridges, ostiole flush with cortical surface, immersed below; conidia not observed.

Chemistry.

Salazinic acid, triterpene 3, zeorin, [-]-16α-hydroxykaurane.

Distribution and ecology.

Mexico, Baja California, North Vizcaíno Desert, between Punta Santa Rosalillita and Punta Negra. Only known from that locality. On rock ledges of north-facing cliffs bordering estuary inland from the sea, occurring with species of Niebla , Vermilacinia cedrosensis and V. paleoderma , within a semicircular arc of volcanic coastal hills with steep ravines and narrow ridges trending in various directions, 200-400 m in altitude, extending approx. 20 km along the coast and to 7 km inland at midpoint near the Punta Negra Road (Google Earth 2019). Fog often lingers amongst the higher ridges and peaks during the day ( Spjut 1996). A diversity of saxicolous Vermilacinia occurs here: V. breviloba , V. cedrosensis , V. ligulata , V. paleoderma , V. pustulata , V. reptilioderma and V. rigida . Vegetation on hills near type locality consists of spiny shrubs and succulents of Pachycormus discolor , Stenocereus thurberi , Cylindropuntia spp., Fouquieria diguetii and Agave shawii . The subshrub Xylonagra arborea was observed on rocks amongst the lichens and salt-scrub of Atriplex julacea and Frankenia palmeri bordered a salt marsh of aquatic species not studied.

Etymology.

Epithet breviloba refers to the short lobes.

Remarks.

Vermilacinia breviloba appears related morphologically to V. polymorpha and V. robusta , neither of which could be included in our phylogeny. Vermilacinia polymorpha was described by Bowler et al. (1994) from a specimen collected by Janet Marsh on Santa Catalina Island. V. robusta , a widespread species, differs by its much larger, terminally round inflated branches with a relatively smooth cortical surface. Vermilacinia polymorpha differs by its deflated-canaliculate branches near base. Both V. polymorpha and V. robusta occur in the USA/California and Mexico/ BC Chaparral, mostly in the Channel Islands; the latter species is also on Isla Guadalupe.

Additional specimens examined.

Same locality as the type: R. Spjut & E. Sérusiaux 17121, 17126, 17128b, 17129b.

Conservation Status.

Prior to year 2000, Puerto San Andrés was accessible directly from San Andrés Ranch, which appeared occupied at the time and not far from where V. breviloba occurs (Spjut pers. obs.). In January 2016, the ranch was not seen while we observed a new earth road that circumvented the estuary by passing north over a saddle and down across a wide arroyo to the north end of Puerto San Andrés, ca. 7 km southeast of Punta Rocosa via a precipitous rocky coastline (Google Earth 2019). A mixed community of local fishermen and nomads appear to reside at Puerto San Andrés. The most disturbance to lichens - evident to Spjut - was on the volcanic hill along the earth road that passes between the estuary and the arroyo north of the pass and also at the north end of Puerto San Andrés. An example is a strongly inflated form of N. podetiaforma observed in May 1985 to be common on pebbles on the rain shadow side of the hill ( Spjut 1996, coll. Spjut and Marin 9077, distributed to many herbaria). This species was not seen there during our Jan 2016 visit. Two other earth tracks from Punta Negra road towards the coast could not be found in January 2016, one that seemed to have been created sometime between May 1986 and March 1988 that led to Punta Rocosa through Krutsio Ranch and a much older track originating about midway between Puntas Negra and Santa Rosalillita that led into the hills along a narrow arroyo where Spjut, Marin and McCloud in May 1986 found closer foot access to the higher elevation ridges. This latter track, which was not evident from ground level in Jan 2016, is evident from Google Earth (2019), whereas the track to Krutsio Ranch appears to have weathered beyond recognition along with the ranch. Thus, much of this rocky coastal region between San Andrés and Punta Negra is protected by its isolation from being inaccessible by road. Additionally, the type locality is accessible only by foot in a direction opposite to where visitors travel to Puerto San Andrés.

Figures

Figure 13. New species of saxicolous Vermilacinia A, B V. breviloba (holotype) C, D V. lacunosa (holotype) E, F V. pustulata (holotype) G, H V. reticulata (holotype). Scale: 1 mm (A, C). Photographs by R. Spjut.