Thysananthus aculeatus Herzog (1931: 89)

Sukkharak, Phiangphak, 2015, A systematic monograph of the genus Thysananthus (Lejeuneaceae, Marchantiophyta), Phytotaxa 193 (1), pp. 448-450 : 448-450

1. Thysananthus aculeatus Herzog (1931: 89) . Type: PHILIPPINES. Laguna and Quezon: Mt. Banahao, 20 December 1913, Baker 7079 (lectotype, here designated JE!; isolectotypes PC!, U!), ibid., Baker 7083 (paralectotype JE!).

Thysananthus formosanus Horikawa (1934: 252) . Type : TAIWAN. Taito: between Shinsuiei and Shucho-kyokai, 3 January 1933, Y. Horikawa 10622 (holotype HIRO!).

Thysananthus richardsianus Verdoorn (1934a: 173) . Type : MALAYSIA. Sarawak: “ G. Balapau, Ulu Tinjar, in silvis et ad arb. truncos, 750 m, November 1932 ”, P.W. Richards s.n. [Hep. Sel. Crit. Verdoorn 398] (holotype FH!; isotypes BM!, BR!, C!, F!, G! 2 packets, GOET!, JE!, L! 2 packets, NY!, PC!, S!, U!, W!).

Plants autoicous, with projecting growth, turning upwards and becoming ascending to erect, yellowish brown to dark brown in herbarium specimens, up to 3.5 cm long × 1–1.8 mm wide. Stems rather rigid; ventral merophyte 9–10 cell rows wide; stem in cross section orbicular, 200–211 µm high × 160–180 µm wide, 10–14 cell layers high, composed of 38–42 epidermal cells surrounding 103–121 medullary cells, epidermal cells as large as medullary cells. Leaves imbricate, when dry suberect and convolute, when moist weakly convex, apical part plane, not recurved; dorsal lobe asymmetrically ovate, 0.8–1 × 0.5–0.7 mm, apex obliquely acute, dorsal base cordate, dorsal margin with 4–7 triangular teeth, the teeth consisting of 3–4 cells, being 2–3 cells wide at base, apex of one cell, ventral margin slightly incurved, with 12–13 triangular teeth, the teeth consisting of 3–5 cells, being 2–3 cells wide at base, apex of one cell; cells elongate-hexagonal with acute ends, vitta absent, marginal cells 7–12 × 7–10 µm, median cells 22–35 × 7–10 µm, basal cells 25–50 × 10–22 µm, trigones cordate, often coalesced, intermediate thickenings 0–2 per cell; oil bodies 3–4 per cell ( Mizutani, 1961). Lobules oblong-rectangular, 0.2–0.3 × 0.1–0.2 mm, 1/4–1/3 × lobe length, the lobule terminating at the end of the keel or joined for a short distance to the ventral margin of the dorsal lobe; appendage on surface of lobule base not developed; keel without appendage; lobule apex truncate, with one triangular tooth, the tooth consisting of 4–6(– 36 in Baker 7083) cells, being 2–6 cells wide at base and ending in a row of (1–)2–3 cells. Underleaves imbricate, channeled or hollow, obovate, 0.5–0.6 × 0.4–0.5 mm, 2–3 ×stem width, apex truncate, plane, margin with 8–15 triangular teeth, the teeth consisting of 3–4 cells, being 2 cells wide at base, apex of one cell, bases cuneate, underleaf bases adnate with leaves on one side, on left-hand side for right branches and right-hand side for left branches; cells 13–20 × 7–10 µm. Androecia terminal-intercalary on lateral branches, bracts and bracteoles in 3–12 pairs, bracts hypostatic, 0.7–0.8 × 0.5–0.6 mm, apex acute, margins entire; antheridia 2 per bract. Gynoecia with 2 lejeuneoid innovations forming a dichasial pattern; lobe ovate, 0.5–1.4 × 0.3–0.7 mm, apex apiculate, margins in upper 1/3 with triangular teeth, the teeth consisting of 3–5 cells, being 2–3 cells wide at base, apex of one cell; lobules broadly ovate, 1/2–2/3 × lobe length, apex apiculate, margins with triangular teeth, the teeth consisting of 3–5 cells, being 2–3 cells wide at base and ending in row of 1–2 cells; bracteoles spathulate, 1.2–1.3 × 0.7–0.8 mm, apex emarginate, 1/3 × bracteole length with triangular teeth, the teeth consisting of 3–5 cells, being 2–3 cells wide at base, apex of one cell, margins plane. Perianths oblong-cylindrical, 1.7–1.8 × 0.7–0.8 mm, keels in upper 1/3 with triangular teeth, the teeth consisting of 3–5 cells, being 2–3 cells wide at base and ending in a row of 1–2 cells; beak 53–71 µm (3 cells) in length or absent. Figs. 8 , 9 .

Additional illustrations:— Herzog (1931, p. 88, Fig. 3 ); Horikawa (1934, p. 20, Figs. 1–10 as Thysananthus formosanus ); Mizutani (1961, p. 154, Fig. VI. 1–23).

Distribution and ecology:— Southern Japan, Taiwan, Malaysia (Borneo), and the Philippines; 200–2350 m; on moist rocks along streams and on bark of trees in the understory of lowland rain forests and montane forests. Fig. 5I .

Thysananthus ( Lejeuneaceae , Marchantiophyta) Phytotaxa 193 (1) © 2015 Magnolia Press • 21

Representative specimens:— Japan. KAGOSHIMA: Amami Ōshima, Kawauchi river, 1 December 1988, Inoue s.n. ( BR, C, G, L, NICH, PC, S, U); along trial above Nakama toward Mt. Shichigodake , Iwatzuki & Sharp 15764 ( NICH) ; slopes of the Tainokawa valley above the sugar mill, 8 December 1964, Iwatzuki & Sharp 14807 ( NICH 2 packets); Mt. Yuwan, Iwatsuki & Suzuki 10514 , Yamaguchi 18285, k8274, Amano 8391 ( NICH) ; Todoroki-no-taki falls, Iwatsuki & Suzuki 11557 ( NICH) ; Yakusugi land, Asakawa & Harrison 69 ( NICH) ; Suzukawa near Onoaida, Mizutani 10131, 10132, Hattori 6995 ( NICH) , 10313, 10372 (L, NICH, S); Tainokawa near Onoaida, Mizutani 10432, 10456, 10457, 10493 ( NICH) ; broad-leaved evergreen forest side of Tainokawa river, Iwatzuki & al. 11017 ( NICH) ; Mt. Motchomu, Mizutani 10707 ( NICH) ; Miyanoura, July 1951, Amakawa s.n. (C, L, S, W); along Hanaage river, Tagawa & Kitagawa 561 (S, W); along Odagumi river , Tagawa & Kitagawa 939 (S, W); Yakushima , Faurie 750 ( BM, G), July 1900, Faurie s.n. ( PC) , July 1951, Amakawa s.n. ( HIRO 4 packets, NICH), 27 March 1999, Izawa s.n. ( NICH) , 14 April 1950, Hasegawa & al. s.n. ( NICH) ; Kosugidani, Shin 3775 ( NICH) ; Mt. Inogawa-dake, Takaki & Katsurayama 37892, 37949 ( NICH) ; Mt. Yuwan, Takaki & Katsurayama 37775, 37468 ( NICH) ; upstream area of Sumiyo-gawa river, Takaki & Katsurayama 37636 ( NICH) .— OKINAWA: Ryukyu Islands, Oogimi, 28 January 1955, Amano s.n. ( BM, BR, C, F, G, HIRO, L, NICH, S, W), Mt. Aha , Amano 8372 ( NICH) ; Inokawa river, Ando E8814 (F), Taiho river , 23 July 1989, Asaaki s.n. ( HIRO) ; Mt. Yonaha-dake, Iwatzuki 12967, Amakawa 8462, Takaki 38673, 38674 ( NICH) ; Nuuha river, Kanashiro 659 ( NICH) . Taiwan. TAITO: between Shinsuiei and Shucho-kyokai , 3 January 1933, Horikawa 10584, 10602, 10604, 10642, 10654, 10657, 10688, 10690, 10693 ( HIRO) , 10642 ( HSNU) (J. Wang, pers. comm.) . Philippines. BENGUET: Baguio, Mt. Santo Tomas, Onraedt 84.P.10959 ( BR, JE) , Aptroot 20370a ( U) .— ORIENTAL MINDORO: Mt. Halcon, Salgado 88.P.12142 ( BR) , “ Dhenill 5709a” (G) .— ZAMBALES: without location, December 1907, Curran & Merritt s.n. (G) .

Taxonomic notes:— Mizutani (1961) considered Thysananthus formosanus and T. richardsianus as synonyms of T. aculeatus . In addition, he showed that the difference between T. aculeatus and T. richardsianus is only the size of the first tooth of the leaf-lobule. Variation in shape and size of the teeth of the leaf-lobule is common and is also seen in, e.g., Spruceanthus semirepandus ( Nees 1830: 39) Verdoorn (1934a: 153) , Leucolejeunea xanthocarpa (Lehmann & Lindenberg in Lehmann 1833: 8) Evans (1907: 229), etc. In the present study it appeared that T. formosanus is somewhat intermediate between T. aculeatus and T. richardsianus , having the appearance and innovation pattern as in T. aculeatus and the curved, elongate lobule teeth of T. richardsianus . I, therefore, treat them all as one species and reduce T. formosanus and T. richardsianus to synonyms of T. aculeatus . The type of T. richardsianus was distributed by Verdoorn in his exsiccata series (F. Verdoorn (ed.), Hep. Sel. Crit. VIII: 398) and the label data of the exsiccata are slightly different from the specimen data in the original publication.

Gradstein et al. (2002) treated Thysananthus aculeatus as a synonym of T. spathulistipus whereas Verdoorn (1934a) treated the two taxa as separate species. The difference between both taxa was discussed by Verdoorn (l.c.). Based on examination of a number of collections, I found that the asymmetrical leaves (symmetrical in T. spathulistipus ), the transverse lobule apex not or slightly continuing into the ventral lobe margin (lobule apex oblique, free margin continuing into the ventral lobe margin in T. spathulistipus ) and channeled/hollow obovate underleaves (spathulate in T. spathulistipus ) in T. aculeatus allow to keep both taxa separate.

Thysananthus aculeatus was described by Herzog in 1931 based on two specimens, Baker 7079 and 7083. The two specimens are different in the number lobule tooth cells (4−6 cells in specimen nr. 7079 versus 12−36 cells in nr. 7083). In the original description, the variation in lobule teeth was not mentioned, however, the original figure of the lobule teeth was drawn from specimen nr. 7079 only. I have chosen the latter specimen as the lectotype of this species because it is good material with perianths.

Figures

FIGURE 1. Method of measurement in Thysananthus. A. Leaf, ventral view; a = appendage, d = dorsal leaf margin, f = lobule free margin, k = keel, l = leaf length, lb = lobule length, t1,2 = lobule teeth, u = auricle, v = ventral leaf margin, w = leaf width, wb = lobule width. B. Underleaf, ventral view; u = auricle, l = underleaf length, w = underleaf width. C. Perianth, ventral view; b = beak, l = perianth length, w = perianth width. D. Portion of shoot with Lejeunea-type branching, ventral view; c = collar. E. Portion of shoot with androecia, gynoecium, and lejeuneoid innovation (dichasial pattern), ventral view. F. Flagellum at stem base, ventral view. G. Dorsal leaf bases are distinctly extending across the dorsal midline of the stem, indicating that lateral merophytes are dorsally interlocking; h= hyaline papillae. H. Underleaf base in longitudinal section. (A from the lectotype of T. appendiculatus; B–C from the holotype of T. discretus; D from T. spathulistipus, Sukkharak 766 (BKF, GOET); E from T. spathulistipus, Sukkharak 746 (BKF, GOET); F from isolectotype of T. comosus; G from T. spathulistipus, Sukkharak 716 (BKF, GOET); H from holotype of T. discretus).

FIGURE 2. Leaves and underleaves adnation and appendages in Thysananthus. A. Portions of plant, ventral view; d = adnation, a = appendage. B. Adnation in longitudinal section. C. Appendages at bases of leaf keels. D–F. Female bracts, ventral view; a = appendage. G. Appendage and hyaline papilla at base of bract keels; h = hyaline papilla. H. Appendage at mid-basal portion of bract lobule. I. Perianth, ventral view; a = appendage. J. Appendage and hyaline papilla of perianth; h = hyaline papilla. K. Portions of plant showing appendage at lobule base, ventral view; a = appendage. L. Appendage; b = lobule, a = appendage, h = hyaline papilla, s = stem. (A from the isolectotype of T. comosus; B from T. spathulistipus, Sukkharak 766 (BKF, GOET); C, E, H from the holotype of T. discretus; D from the holotype of T. gottschei var. continuus; F from T. appendiculatus, Gradstein 3875 (U); G from T. appendiculatus, Streimann & Tamba 12358 (JE); I–J from T. mollis, Gradstein 3795 (U); K from T. retusus subsp. retusus, Sukkharak 733 (BKF, GOET); L from T. montanus, Streimann 13639 (LAE)).

FIGURE 3. Androecia, gynoecia, and young sporophyte in Thysananthus. A. Portion of androecial spike showing epistatic and hypostatic lobules, ventral view: e = epistatic, h = hypostatic. B. Male bract with 2 antheridia. C. Antheridia. D. Juvenile perianth. E. Perianth and protruding archegonial neck. F. Archegium and archgonial neck. G. Later stage of development. H. Sporophyte prior to elongation of seta. I. Sporophyte after partial elongation of seta. J. Mature perianth, just dehiscence. K. Transverse section of seta. (A from T. amazonicus, Cornelissen & Steeger C682 (U); B from T. spathulistipus, Gradstein 3964 (U); C from T. spathulistipus, Gradstein 3965 (U); D–G from T. spathulistipus, Sukkharak 766 (BKF, GOET); H–I, K from T. retusus subsp. retusus, Streimann 40547 (JE); J from T. spathulistipus, Sipman 6992 (U)).

FIGURE 4. Sporophyte in Thysananthus. A. Outer surface of capsule valve, showing rectangular-shaped hinge. B–D. Cells of the outer layer of the capsule valve, surface view. E. Inner surface of dehiscing capsule, showing base of capsule and longitudinal ridges. F. Cells of the inner layer of the capsule valve, surface view. G. Inner surface of dehiscing capsule, showing elaters patterns of either 1+3+5+6 or 2+4+6+6 per valve. H. Elaters. I. Spores. (A–G from T. spathulistipus, Yong & Ponniah 2981 (GOET); H from T. spathulistipus, Thiers & Roy 2397 (U); I from T. spathulistipus, Sipman 6992 (U)).

FIGURE 5. Distribution of Thysananthus species. A. Thysananthus amazonicus (Spruce) Schiffn. B. Thysananthus spathulistipus (Reinwardt, Blume & Nees) Lindenb. C. Thysananthus convolutus Lindenb. D. Thysananthus mollis Steph., E. Thysananthus pancheri (Steph.) Hürl. F. Thysananthus anguiformis (Hook.f. & Taylor) Taylor ex Gottsche, Lindenb. & Nees G. Thysananthus comosus Lindenb. H. Thysananthus fruticosus (Lindenb. & Gottsche) Schiffn. I. Thysananthus aculeatus Herzog. J. Thysananthus appendiculatus Steph. K. Thysananthus montanus Gradst., X.-L. He & Piippo. L. Thysananthus retusus (Reinw., Blume & Nees) B.M.Thiers & Gradst. M. Thysananthus gottschei (Jack & Steph.) Steph. N. Thysananthus ciliaris comb. nov. O. Thysananthus discretus Sukkharak & Gradst.

FIGURE 6. Bayesian molecular phylogenetic reconstruction inferred from the combined chloroplast and ITS dataset, excluding one sample of Thysananthus pancheri which showed conflicting positions in the chloroplast and ITS trees. Branch thickness and color indicate posterior probability values from Bayesian analyses with gaps treated as missing data (BPP) and with indels coded by SIV (BPPSIC) as well as bootstrap support from respective maximum parsimony analyses (MPB, MPBSIC). Modified after Sukkharak et al. (2011b).

FIGURE 7. Bayesian molecular phylogenetic reconstructions inferred from the separated chloroplast (A) and ITS (B) datasets, including differences in sequence lengths (indels) coded by simple indel coding (SIC). Modified after Sukkharak et al. (2011b).

FIGURE 8. Thysananthus aculeatus Herzog. A. Portion of shoot, ventral view. B–C. Leaves, ventral view. D. Underleaves, ventral view. E. Female bracts, ventral view. F. Female bracteole, ventral view. G. Perianth, dorsal view. H. Perianth, ventral view. I. Leaf apices. J. Margin cells of leaf lobe. K. Median cells of leaf lobe. L. Basal cells of leaf lobe. M–O. Leaf lobule apices. P. Cross section of stem. (A–B, D–M, P from the lectotype; C, N, O from the paralectotype).

FIGURE 9. Thysananthus aculeatus Herzog. A. Portion of shoot, ventral view. B., C. Leaves, ventral view. D., F. Perianth, dorsal view. E., G. Perianth, ventral view. H–K. Leaf lobule apices. (A, C, F, G, I–K from the holotype of T. richardsianus; B, D, E, H from the holotype of T. formosanus).

FIGURE 10. Thysananthus amazonicus (Spruce) Schiffn. A. Portion of shoot, ventral view. B. Leaves, ventral view. C. Underleaves, ventral view. D. Female bracts, ventral view. E. Female bracteole, ventral view. F. Perianth, dorsal view. G. Perianth, ventral view. H–J. Leaf apices. K. Margin cells of leaf lobe. L. Median cells of leaf lobe. M. Basal cells of leaf lobe. N–Q. Leaf lobule apices. R. Cross section of stem. (All from Gehrig s.n. (GOET)).