Taxonomic notes
Thottea philippinensis was originally described by Eduardo
Quisumbing in 1930 based on specimens collected by T.N. Roque from Lanao
Province in the island of Mindanao. Although it has been recollected
twice in Sarawak (Hou 1984), the species have never been rediscovered in
the Philippines since it was first discovered. Through our extensive
fieldwork in Zamboanga Peninsula, on the island of Mindanao, the species
has recently been rediscovered after a lapse of 93 years.
According to Hou (1984), Thottea philippinensis closely resemblesT. celebica of Sulawesi (previously known as Celebes). However,T. philippinensis differs significantly in having these following
characters: puberolous stem (vs. pubescent in T. celebica );
leaves lateral veins up to 13 (vs. leaves lateral veins up to 10 inT. celebica ); broadly triangular with acute apex perianth lobes
(vs. semi-orbicular with subrotund or slightly apiculate apex perianth
lobes in T. celebica ); and 4–6 style lobes (vs. c. 12
style lobes in T. celebica ).
Thottea tomentosa (Blume) Ding Hou, Blumea 27(2): 328,
f. 48, 49 (1981); Hou, Fl. Males., ser. 1, 10: 79 (1984); Yao, Fl. Pen.
Malaysia 5: 43 (2015). – Ceramium tomentosum Blume, Bijdr. Fl.
Ned. Ind. 17: 1135 (1827). – Bragantia tomentosa (Blume) Blume,
Enum. Pl. Javae 1: 82 (1827); Ridley, J. Straits Branch Roy. Asiat. Soc.
57: 89 (1910); Ridley, J. Straits Branch Roy. Asiat. Soc. 59: 161
(1911). – Apama tomentosa (Blume) Engl. ex Soler., Naturl.
Pflanzenfam. 3(1): 272 (1889); Backer & Bakhuizen f., Fl. Java 1: 162
(1964). (Fig. 3)
Type: INDONESIA. Java, Herb. Blume ‘1690’ (lectotype L
[L0038821], designated by Hou (1981); isolectotype L
[L0038822]).
Thottea tomentosa is one of the widest-ranging species of the
genus distributed from India (Assam: Manipur & S. Andaman Is.),
Bangladesh (Sylhet), Burma (Moulmein), South Vietnam (Bien Hoá),
Peninsular Thailand. In Malesia, it is found in the Malay Peninsula
(throughout), Sumatra, West & Central Java, and the Philippines
(Jayabas, Alabat I., Panay, Mindanao), but it has not yet been found in
Borneo. Although it was reported to occur in the Philippines, this has
become doubtful due to the T. tomentosa found having eight
stamens instead of six, as consistently mentioned in previous studies
(Hou 1981, 1984, Yao 2015, Mustaqim et al. 2022). Therefore, it is
treated as incertae sedis in Co’s Digital Flora of the
Philippines (Pelser et al. 2011 onwards). During our recent extensive
fieldwork conducted in Pasonanca Natural Park, Zamboanga City, we
successfully collected a Thottea species that possesses six
stamens, perfectly matching the characteristics of T. tomentosa .
Consequently, in this paper, we definitively affirm its presence in the
Philippine archipelago, currently restricted to Zamboanga City. However,
other specimens identified as T. tomentosa present in other parts
of the archipelago warrant further investigation, as they may
potentially represent a new species.