Acrostichum hastatum Thunb. ex Houtt.,

Wijnands, Dirk Onno, Heniger, Johannes, Veldkamp, Jan Frederik, Fumeaux, Nicolas & Callmander, Martin W., 2017, The botanical legacy of Martinus Houttuyn (1720 - 1798) in Geneva, Candollea 72 (1), pp. 155-198 : 166

2. Acrostichum hastatum Thunb. ex Houtt.,

Nat. Hist. II(14): Aanwyz. Plaat. [1], 68, tab. 95, fig. 2. 1783.

≡ Pyrrosia hastata (Thunb. ex Houtt.) Ching in Bull. Chin. Bot. Soc. 1: 48. 1935.

Lectotypus (first step designated by VELDKAMP, 2004: 191; second step designated here by Wijnands,Veldkamp, Callmander & Fumeaux): JAPAN: Thunberg s.n. ( G-PREL [ G00818012 ]!; isolecto-: UPS-THUNB n° 24584 image seen) ( Fig. 5 ).

Notes. – The type material is present in the Japan herbarium in G-PREL with Thunberg’s handwriting, and was found by the first author ( Fig. 5 ). THUNBERG (1784: tab. 34) published an illustration of his later isonym that appeared in MURRAY (1784: 928), and original material was located in UPS-THUNB. HOVENKAMP (1986: 186) designated Houttuyn’s plate as the lectotype. However, since the original specimen from which the illustration clearly was made has been located, the lectotypification was superfluous (see Art. 9.19).

In reality, the situation is more complicated, as fully discussed by VELDKAMP (2004), who erroneously assumed that Acrostichum hastatum Thunb. ex Houtt. and A. hastatum Thunb. , both based on Thunberg collections, “might quite possibly be parts of the same gathering” (Art. 8.2). But he went on to write that “because these combinations were based on different specimens deposited in different places” they would be “heterotypic, synonymous homonyms”, as has previously been pointed out by TAGAWA (1957: 354).

This is not in agreement with Art. 9.3. Accordingly, here and elsewhere, the specimens collected by Thunberg and used by Houttuyn and by Thunberg are regarded as duplicates of the same gathering. Houttuyn’s names are generally the older ones (see Osmunda japonica Houtt. below under n° 76 for an exception). In the present case, the name published by Thunberg is an isonym with no nomenclatural status (Art. 6.3 Note 2). The author citation should therefore be adjusted (but see above), making the correct name Pyrrosia hastata , by which name this ornamental species is universally known.

Figures

Fig. 5. – Lectotype of Acrostichum hastatum Thunb. ex Houtt. in Houttuyn's Japan herbarium in G-PREL.