Cladopus fallax, C. Cusset

Kato, Masahiro, Werukamkul, Petcharat, Won, Hyosig & Koi, Satoshi, 2019, Paraphyletic Species of Podostemaceae: Cladopus fallax and Polypleurum wallichii, Phytotaxa 401 (1), pp. 33-48 : 38

Cladopus fallax

Cladopus fallax was distinguished from other congeners by combined characters. It differs from C. taiensis in the form (surface-viewed and in cross section), surface and number of the bract-segments, from C. nymanii H.Möller in the length of the stamens and the number of ovules, from C. queenslandicus (Domin) C.D.K.Cook & Rutish. in the length of the flowering shoots and the number and form of the bracts, and from C. javanicus M.Kato & Hambali in the length of the flowering shoots, the number of the bracts, and the length of the capsules and capsule stalks ( Table 2 ).

In the chloroplast matK tree ( Fig. 1 ), Cladopus was divided into two clades with robust support. One clade (upper in Fig. 1 ) was subdivided into three subclades, i.e. a subclade consisting of C. fallax -1 from Cambodia, C. fallax -2 from Thailand and C. taiensis ; a subclade of C. javanicus , C. nymanii and C. queenslandicus ; and C. fallax - 3 from Cambodia. Cladopus fallax -1 had the same sequence as the Thai specimens of C. taiensis (TL-101, TL-102, TL-604), the two were sister to the other C. taiensis from Cambodia and Thailand, and all were sister to C. fallax -2. Geographically, C. fallax -1 is adjacent to C. taiensis (CAM-07, CAM-14) of Cambodia (4.2 or 12.2 km apart) and far from the Thai populations.

The nuclear ITS tree ( Fig. 2 ) showed that there are variations in the ITS regions of C. fallax CAM-13, C. fallax CAM-19 and C. taiensis CAM-14, while uniform in others (e.g. C. fallax CAM-26, C. fallax CAM-41, C. fallax TKF-109, C. taiensis TL-604). The variants of CAM-13 and CAM-19 of C. fallax -1, and CAM-14 of C. taiensis were grouped in each clade, although one C. fallax CAM-13 was isolated. These samples of C. fallax -1 and C. taiensis formed a monophyletic clade, with low support, which was sister to C. fallax -2 and together sister to C. fallax -3.

In the combined matK and ITS tree, C. fallax -1 and C. taiensis were monophyletic and sister to C. fallax -2 ( Fig. 3 ). Then, C. fallax -1, C. fallax -2, C. fallax -3 and C. taiensis , together with C. javanicus , were monophyletic.

Figures

FIGURE 1. Bayes phylogenetic consensus tree deduced from matK sequences.Numbers above and below branches are Bayesian posterior probabilities (≥0.80) and bootstrap values (≥50 %) of ML (left) and MP (right), respectively. Single asterisk (*) indicates that specimen JK- Manose is followed by additional specimens with the same sequence, JK-02, JK-Yamazaki, JK-Anraku, JP-127, JK-Mawatari, and CH-02. Double asterisk (**) indicates that specimen CP-07 is followed by additional specimens with the same sequence, CP-22, 24, 27, and 29. For simplicity, species of Hanseniella, Hydrobryum, Hydrodiscus and Thawatchaia examined are united as a single clade (for materials see Appendix). The tree is rooted on a branch between a clade of Cladopus, Hanseniella, Hydrobryum, Hydrodiscus, Paracladopus and Thawatchaia, and a clade of Polypleurum, Griffithella, Hydrobryopsis, Willisia and Zeylanidium.

FIGURE 2. Bayes phylogenetic consensus tree deduced from ITS sequences. Numbers above and below branches are Bayesian posterior probabilities (≥0.80) and bootstrap values (≥50 %) of ML (left) and MP (right), respectively. For simplicity, species of Hydrobryum examined are united as ‘Hydrobryum species’ (see Appendix). The tree is rooted on a branch between a clade of Cladopus, Hanseniella and Hydrobryum and a clade of Polypleurum, Griffithella, Hydrobryopsis, Willisia and Zeylanidium.

FIGURE 3. Bayes phylogenetic consensus tree deduced from concatenated matK and ITS sequences. Numbers above and below branches are Bayesian posterior probabilities (≥0.80) and bootstrap values (≥50 %) of ML (left) and MP (right), respectively. For simplicity, the species of Hydrobryum, both matK and ITS sequences of which were examined, are united as ‘Hydrobryum species’ (Appendix). C. fallax CAM-13a = LC380594 + LC380635; C. fallax CAM-13b = LC380594 + LC380636; C. fallax CAM-13c = LC380594 + LC380637; C. fallax CAM-19a = LC380595 + LC380638; C. fallax CAM-19b = LC380595 + LC380639; C. taiensis CAM-14a = LC380602 + LC380643; C. fallax CAM-14b = LC380602 + LC380644. The tree is rooted on a branch between a clade of Cladopus, Hanseniella and Hydrobryum, and Polypleurum.