Stolonicaulon: A Section-Puzzle within Marsupella (Gymnomitriaceae, Marchantiophyta)

Abstract

Marsupella sect. Stolonicaulon is not speciose and is a commonly neglected section within the genus, which currently includes three species with somewhat similar morphologies (wiry shoots with distanced leaves) and distributions in the mountains of tropical and subtropical regions (SE (Southeast) Asia, the Venezuelan Andes, and the high mountains of SE Brazil). After studying materials that were found to be dissimilar to the "traditional" Marsupella that were collected in the last decade by the authors of this article, it was found that these plants belong to three new-for-science species, and all of these species should be included in Marsupella sect. Stolonicaulon. The newly described species have expanded the boundaries of morphological variability, not only for the section itself, but also for the genus based on two findings: (1) the leaves of Marsupella sect. Stolonicaulon can be either appressed and entire or spaced and deeply divided (thus, the plants could occasionally be similar to Cephaloziella or Anastrophyllum); (2) some species of the section possess regular underleaf production. The first discovery of regular underleaves in Marsupella, as noted in two of the three newly described taxa, is the main morphological novelty described in this paper. The development of regular underleaves is a presumable relict character that brings Marsupella closer to Nardia, which was recently transferred to the Gymnomitriaceae and occupies an isolated position within its own subfamily, Nardioideae.

Keywords: Gymnomitriaceae; Marchantiophyta; Marsupella; Pacific Asia; molecular phylogenetic; phytogeography.

Figure 1

Phylogram obtained in a maximum likelihood calculation for the genus Marsupella based on ITS1-2+trnL-F dataset. Bootstrap support values of maximum likelihood analysis more than 50% and Bayesian posterior probabilities more than 0.50 are indicated.

Figure 2

Marsupella anastrophylloides Bakalin, Vilnet et Maltseva sp. nov.: (A,B) plant habit, fragment, dorsal view; (C,D) plant habit, fragment, ventral view; (E) stem cross-section; (F–N) leaves. Scales: a—500 µm for (A,C); b—1 mm for (B,D); c—100 µm for (E); d—500 µm for (F–N). All from Holotype V-15-6-20 (VBGI).

Figure 3

Marsupella anastrophylloides Bakalin, Vilnet et Maltseva sp. nov.: (A) leaf lobe; (B) plant habit; (C,D) leaves. Scales: 50 µm for (A); 1 mm for (B); 50 µm for (C,D). All from Holotype V-15-6-20 (VBGI).

Figure 4

Collecting locality of Marsupella praetermissa Bakalin et Vilnet sp. nov. (Photo by D. Long, 2006).

Figure 5

Marsupella praetermissa Bakalin et Vilnet sp. nov.: (A) plant habit, fragment, lateral view; (B) plant habit, fragment, ventral view; (C) plant habit, fragment, dorsal view. Scales: a—500 µm for (A–C). All from Holotype Long 35742 (E).

Figure 6

Marsupella praetermissa Bakalin et Vilnet sp. nov.: (A) shoot, fragment, dorsal view; (B) shoot, fragment, lateral view; (C,D) shoot, fragment, ventral view; (E) shoot apex, dorsal view; (F) shoot apex, lateral view; (G) shoot fragment, lateral view; (H) shoot fragment, ventral view; (I) shoot apex, ventral view; (J) stem cross-section. Scales: 200 µm for (A–D); 100 µm for (E–J). All from Holotype Long 35742 (E).

Figure 7

Marsupella taiwanica Mamontov, Vilnet et Schäf.-Verw. sp. nov.: (A) shoot, fragment, dorsal view; (B) shoot, fragment, ventral view; (C) perianthous shoot, fragment; (D) stem cross-section; (E–I) leaves. Scale: a, b—500 µm (A–C,E–I); c—100 µm (B). All from Holotype Schäfer-Verwimp 37663 (MHA).

Figure 8

Marsupella taiwanica Mamontov, Vilnet et Schäf.-Verw. sp. nov.: (A) sterile shoot, fragment, dorsal view; (B) perianthous plant, fragment, lateral view; (C) perianthous plant, fragment, ventral view; (D) perianthous shoot, fragment, ventral view; (E) perianth with female bract; (F,G,J–M) leaves; (H) stem cross-section; (I) female bract. Scales: 100 µm for (F–H,J–M); 200 µm for (A,I); 300 µm for (D,E); 500 µm for (B,C). All from Holotype Schäfer-Verwimp 37,663 (MHA).

Figure 9

Marsupella stoloniformis N. Kitag.: (A) plant habit, fragment, dorsal view; (B) plant habit, fragment, dorsal view; (C) perianthous plant with seta; (D) perianthous plant, lateral view; (E) shoot with underleaves, fragment, ventral view; (J,K) stem cross-section; (F–I) leaves. Scale: a—1 mm for (A–D); b—100 µm for (E); c—0.5 mm for (F–I); d—100 µm for (J,K). (A,D,F–J) from V-11-11-17 (VBGI); (B,C,E,K) from Mizutani 2788 (KYO).

Figure 10

Marsupella stoloniformis N. Kitag.: (A) upper part of female bract; (B) mat, male plants, moist condition; (C) mat, sterile plants, moist condition; (D) mat, plants with perianths and open sporophytes, dry condition. Scale: 50 µm for (A); 1 mm for (B,C); 500 µm for (D). (A) from V-11-28-17 (VBGI); (B) from V-11-24-17 (VBGI); (C) from V-11-12-19 (VBGI); (D) from V-10-14-19 (VBGI).

Figure 11

Marsupella vermiformis (R.M. Schust.) Bakalin et Fedosov: (A) perianthous shoot, fragment, lateral view; (B) perianthous shoot, fragment, lateral view; (C) sterile shoot, fragment, dorsal view; (D–G) leaves. Scale: a—500 µm for (D–G); b—500 µm for (A–C). All from Choi 120911 (VBGI).