Crassitegula garyi L. Le Gall & C. W. Schneid. 2025, sp. nov.
Creators: name: Schneider, Craig W.
name: Gall, Line Le
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Plantae
Rhodophyta
Florideophyceae
Gigartinales
Sebdeniaceae
Crassitegula
Crassitegula garyi

description: Crassitegula garyi L.Le Gall & C.W.Schneid. sp. nov.
Registration: http://phycobank.org/105327
Fig. 3
Diagnosis
Crassitegula garyi sp. nov. produces branched ligulate blades from marginal proliferations that are similar to the finger-like branches of mature C. laciniata, but those of the latter are directly produced from blade margins and not from marginal proliferations. The apices of the new species are rounded, not acute like those of C. laciniata.
Etymology
The species is named for the Canadian macroalgal phylogeneticist, Prof. Gary W. Saunders of the University of New Brunswick, who sorted out the Sebdeniales and co-authored three of the five genera in the order including Crassitegula.
Type material
ITALY • Mesophotic reef off Capo dell’Armi, Reggio Calabria, Calabria, Mediterranean Sea; 37°57′13.932″ N, 15°40′37.200″ E; depth 50 m; 13 Apr. 2011; L. Le Gall and J. Utge LLG3706; GenBank nos PQ213415 (COI-5P), PQ213422 (LSU); holotype: PC [PC0164776].
Additional material examined
FRANCE • Deep reef, Montremian, Port-Cros, Hyères; 43°01′07.26″ N, 06°21′50.09″ E; depth 30 m; 7 Jun. 2009; L. Le Gall and J. Utge LLG2562; GenBank nos PQ213416 (COI-5P), PQ213423 (LSU); PC [PC0162308] • Deep reef, Agay-Saint Raphael, south of Cap Dramont, Var, French Riviera; 43°24′27.41″ N, 06°51′19.44″ E; depth 40 m; 7 Jun. 2013; L. Le Gall LLG5005; GenBank nos PQ213419 (COI-5P), PQ213424 (LSU); PC [PC0144755] • ⊕; Deep reef, southeast of the Cerbicale Islands, Corsica; 41°31′43.85″ N, 09°24′07.96″ E; depth 32–42 m; 16 Oct. 2020; B. Gouillieux, L. Le Gall, A. Le Viavant, W. Bay-Nouailhat, E. Vassard and F. Otero Ferrer LLG6821; GenBank no. PQ213417 (COI-5P); PC [PC0626136] • same collection data as for preceding; B. Gouillieux, L. Le Gall, A. Le Viavant, W. Bay-Nouailhat, E. Vassard and F. Otero Ferrer LLG6822; GenBank COI-5P no. PQ213418 (COI-5P); [PC0626138].
Description
Plants saxicolous, prostrate, dorsiventrally organized, firm and smoothly textured, scarlet to fire brickred (Graf 1x 2023); blades originally reniform to cuneate and irregular, 1–2 cm wide, initially attached by short, submarginal holdfasts, later developing secondary holdfasts from ventral surfaces of spreading blades, blades also affixed to substrate directly by a cuticle-like surface covering ventral surface cells (Fig. 3A); primary blade later proliferating multiple new small circular to spathulate blades from margins, these eventually developing into long ligulate dorsiventral blades in the same plane; ligulate blades overlapping and affixed to one another by occasional secondary holdfasts issued from margins (Fig. 3A); blades 340–630 µm thick with rounded to nearly squared-off margins (Fig. 3B); axes multiaxial, medulla densely filamentous with long, thin, interwoven filaments 3–6 µm in diam., mostly periclinal to blade axis (Fig. 3B), and secondarily pit-connected to other medullary filaments and inner cortical layer by stellate ganglia with bodies 6–12 µm diam. with multiple radiating extensions; cortex 6–9 layered with broad transversely ellipsoidal to subglobose large inner cortical cells 36–60 µm in longest diam., each layer grading to the smallest outer cortical cell layer (Fig. 3E), cells irregularly ellipsoidal perpendicular to surface, 3.5–4.5 µm diam. and 6.0–7.5 µm tall, rounded angular and loosely to closely spaced in surface view, at times in arching lines (Fig. 3C); tetrasporangia elongated obovate, irregularly cruciately divided, 7.5–? µm diam., 15–? µm long, on attenuated outer cortical cells in slightly raised nemathecia on the ventral surface (Fig. 3D); gametangia and carposporophytes unknown.
Remarks
The only sporangia of Crassitegula garyi sp. nov. that were discovered were undivided or just oncedivided in their nemathecia, but the oblique first meiotic division showed that this species was likely going to have similar irregularly cruciate tetrasporangia to others in the genus.
Distribution and habitat
At present, known from 30–50 m reefs off France, including Corsica, and Italy in the northern Mediterranean Sea.
description: Published as part of Schneider, Craig W. & Gall, Line Le, 2025, Two new species of Crassitegula (Sebdeniaceae, Sebdeniales, Rhodophyta) extend the diversity and biogeographic range of the genus to the Caribbean and Mediterranean seas, pp. 194-207 in European Journal of Taxonomy 976 on pages 202-204, DOI: 10.5852/ejt.2025.976.2789, http://zenodo.org/record/14922241