Ischaemum thomsonianum Stapf ex C.E.C. Fisch.

Gurappa, Settipalle & Kumar, Thiruppathi Senthil, 2022, Lectotypification of Ischaemum thomsonianum Stapf ex C. E. C. Fisch. (Poaceae: Panicoideae: Andropogoneae), Adansonia (3) 44 (20), pp. 211-214 : 212

Ischaemum thomsonianum Stapf ex C.E.C. Fisch.

( Fig. 1 )

Flora of the Presidency of Madras 3: 1722 ( Fischer 1934).

TYPE CITATION. — “ Mysore; Cochin; Travancore; up to 3,000 ft. ”.

LECTOTYPE (here designated). — India. Maisor & Carnatic, G. Thomson s.n. (lecto-, K [ K000245702 , image]! ; isolecto-, K [ K000245701 , image]!; E [ E00393557 , image]!).

DISTRIBUTION. — India. Karnataka, Kerala, Maharashtra and Tamil Nadu.

REMARKS

Hooker filius (1897: 135) identified the grass specimens of G. Thomson from “Mysore or the Carnatic” as Ischaemum murinum Forst. in September 1889, C.B. Clarke dissected the type material, illustrated it (as can be seen from the original material of two sheets at Kew, cited in the ‘Introduction’) and identified it to be the species of Forster (Forster 1780: 185). But, later, on examination, O. Stapf found it different from the New Caledonian species I. murinum Forst. (Native range from New Guinea to SW Pacific) and assigned the name I. nonum Stapf (det.; s.d.).

Having confirmed of its distinct identity, Fischer (1934: 1722) provided a new replacement name “ Ischaemum thomsonianum, Stapf MS. , n. nom. differently from I. murinum Hook. f. non Forst. ; FBI. vii. 135”, as suggested by Stapf in preference (cf. determinavit slip on the original material by C.E.C. Fischer; 14.IX.1932 at K and 20.XII.1932 at E.

No later homonym situation arise in the present case but misapplication of a validly published name.

While proposing the new name in Flora of Madras, Fischer (1934: 1722) proposed the name in the species list of Ischaemum with its distribution as “Mysore; Cochin; Travancore; up to 3,000 ft. ’. The name has a diagnostic key ( Fischer 1934: 1719) but no description following the name, as per the format of Flora of Madras. The description was provided earlier by Hooker filius (1896 [“1897”]). Moreover, Fischer (1934: 1722) proposed a new name but not a new species, which was an error. However, having mentioned “non G. Forst.” he excluded its type. Conversely, I. thomsonianum is an accepted name ( Bor 1960; Karthikeyan et al. 1989; Sur 2001; Srivastava & Nair 2010; Kellogg et al. 2020) but needs lectotypification according to ICN for Algae, Fungi, and Plants ( Turland et al. 2018).

Finally, of the original material housed at Kew, the specimen K000245702 is the most suitable having pencil sketches (drawings of dissected floral parts pasted at one place) by C.B. Clarke , and the sheet matches well with the key provided by Fischer in Flora of Madras ( Fischer 1934: 1719). Therefore, it was chosen and designated here as lectotype for I. thomsonianum Stapf ex C.E.C. Fisch .

Figures

FIG. 1. — Lectotype of Ischaemum thomsonianum Stapf ex C.E.C. Fisch. (K000245702). © The Board of Trustees of the Royal Botanic Gardens, Kew.