Calypogeia lunata Mitt., J. Proc. Linn. Soc., Bot. 5 (18): 107. 1860 [1861].

Bakalin, Vadim A., Klimova, Ksenia G. & Nguyen, Van Sinh, 2020, A review of Calypogeia (Marchantiophyta) in the eastern Sino-Himalaya and Meta-Himalaya based mostly on types, PhytoKeys 153, pp. 111-154 : 111

Calypogeia lunata Mitt., J. Proc. Linn. Soc., Bot. 5 (18): 107. 1860 [1861]. Figures 4L-S , 5G-J

Type.

India. Assam: Griffith (syntype: G [G00064229/5288!]).

Remarks.

This is a broadly Sino-Himalayan endemic species that seems locally abundant in the eastern Sino-Himalaya. Mitten (1860) described Calypogeia lunata from Assam; later, Singh and Nath (2007a) recorded it from the East Khasi Hills and West Khasi Hills in India. Aside from India, the species was reported from eastern Nepal, Bhutan, Thailand and Yunnan Province in China ( Mizutani 1979; Lai et al. 2008; Kitagawa 1988; Hattori 1975, Piippo 1990; Piippo et al. 1998; Long and Grolle 1990). The origin of the report of the species for Yunnan is unclear. Piippo (1990) mentioned C. lunata for Yunnan with reference to Grolle (1966), who does not, however, provide label data for this species in Yunnan, although it is also indicated in the review of the general distribution.

The description based on the isotype is as follows: plants brownish to blackish brownish in the herbarium, translucent, glistening, 1.5-2.2 mm width; stem 120-220 µm wide, branching not seen; rhizoids sparse to common in brownish grayish, erect to obliquely spreading loose fascicles; leaves overlapping ~1/4-1/3 of next leaf basal part, slightly convex, with apices somewhat turned to ventral side, obliquely inserted and oriented, ventrally clearly decurrent to 1.0 of stem width or less, widely triangular-ovate, apex acute to obtuse (very rarely bilobed), 850-1200 × 770-1200 µm, margin entire to somewhat crispate; underleaves decurrent for (0.3-)0.5-1.0 of stem width, 1.5-3.5 as wide as stem, bisbifid or with each main lobe divided into three small lobes, or bisbifid with additional lateral tooth on each side; midleaf cells thin-walled, trigones vestigial, cuticle smooth, 30-38 × 20-33 µm (the cell measurements may be incorrect because of collapsed leaf cells).

The species is most morphologically similar to Calypogeia goebelii ( Kitagawa 1988), from which, however, it differs in underleaf width and shape, long decurrency of underleaves, rarely shortly bifid leaves (versus underleaves commonly less than 2 times as wide as stem and leaves deeply incised). In contrast to mainly Malesian-Papuasian C. goebelii , C. lunata is characterized by an eastern Sino-Himalayan distribution, where C. goebelii can hardly be expected. We hypothesize that the reports of C. goebelii from Thailand ( Kitagawa 1988 and subsequent mentions based on this) represent the ill-developed modification (probably from dry habitats) of C. lunata . On the other hand, C. lunata seems to be very closely morphologically related to C. latissima (Philippines, see below), from which, however, it differs in its completely smooth cuticle and very rarely (as exclusion) bidentate leaves.

One more observation should be made on the type specimen identification. The specimen in JE marked as the possible type (JE-H2316 = JE04005930!) is actually not the type. The label means that the specimen was collected in "Khasia, Churra", not in Upper Assam, as in the original description by Mitten (1860). The plants in the Jena ‘type’ are different from the typical C. lunata and rather resemble C. tosana or C. goebelii , although they differ from both in thickened leaf cell walls in dorsal half of leaves (especially in the external wall), V-shaped leaf sinus and 3-5 cells high undivided portion of underleaf. We speculate that the specimen may belong to an undescribed taxon, but we refrain from describing it here until fresh material suitable for DNA and oil body characteristics is obtained.

Figures

Figure 4. Calypogeia granulata Inoue: A plant habit, fragment, ventral view B plant habit, fragment, dorsal view C, D, H, I, J leaves E, F, G, K underleaves Calypogeia lunata Mitt.: L plant habit, fragment, ventral view M, N, O leaves P, Q, R, S underleaves Calypogeia marginella Mitt.: T plant habit, fragment, ventral view U, V, W, X, AB, AC underleaves Y, Z leaves AA plant habit, fragment, dorsal view Calypogeia tosana (Steph.) Steph. AD, AE, AF leaves AG, AH underleaves. A-G from Syntype G 00114896; L, P-S from Long no 10664, JE H-K from 18004 TNS 174361; M-O from Syntype G 00064229 / 5288; T-Z from Syntype G 00113555 / 5289; AA, AB, AC from Syntype JE- 04005904; AD, AE, AF, AG, AH from Lectotype G 00047274 / 26013.

Figure 5. Calypogeia granulata Inoue: A plant habit, fragment, ventral view B, F underleaves C leaf middle cells D, E leaves Calypogeia lunata Mitt.: G, H leaves I, J underleaves. Scale bars: 500 µm (A, B, D, E, G, H); 200 µm (F, I, J); 50 µm (C). A, B, C from Holotype 18004 TNS 174361; D, E, F from Isotype G 00114896; G, H, I, J Syntype G 00064229 / 5288.