Biddulphia quinquelocularis Kützing, 1844

Williams, David M., 2021, Studies on type material from Kützing’s diatom collection VI: The identity of Diatoma liber Suhr (1831), Phytotaxa 528 (3), pp. 215-223 : 217-219

3. Biddulphia quinquelocularis Kützing (p. 138, pl. 19, fig. I, 1, 2)

Both Diatoma liber and Diatoma interstitiale are cited in Kützing (1844, 1849) as synonyms of his Biddulphia quinquelocularis Kützing (Kützing, p. 138, pl. 19, fig. I, 1, 2, see Fig. 7; ‘ Biddulphia quinquelobata’ was an alternative name used only for herbarium material). Although described as new, Kützing included a number of apparent synonyms ( Table 2) as well as numerous localities ( Table 3, marked with Y in the last column). Most subsequent commentators have considered Biddulphia quinquelocularis a synonym of Biddulphia biddulphiana (J.E. Smith) Boyer (1900, p. 694) .

4 The packet in the BM herbarium is slightly different, having the following: “ Biddulphia septemcostata ’ Kg. | Diat. interstitiale Ag. | Diatoma liber Suhr | Isthmosira [ Isthmia ] canariensis Kg. | Kützing | 823” ( Fig. 12b).

5 One further name is worth mentioning in passing. ‘ Diatoma obliquata (E.B.) Agardh’ (1817, p. xxxv) is sometimes given with ‘E.B.’ as its basionym author. ‘E.B.’ actually means ‘English Botany’. ‘E.B.’ is noted for Diatoma taeniaeformis , Diatoma striatula , Diatoma obliquata and Diatoma stipitata in Agardh (1817, p. xxxv). These should be cited as:

Diatoma obliquata (J.E. Smith 1808a, ‘English Botany’, tab. 1869) Agardh 1817, p. xxxv

Diatoma taeniaeformis (J.E. Smith 1808b, ‘English Botany’, tab. 1883) Agardh 1817, p. xxxv

Diatoma striatula (J.E. Smith 1808b, ‘English Botany’, tab. 1928) Agardh 1817, p. xxxv

Diatoma stipitata (J.E. Smith 1813, ‘English Botany’, tab. 2488) Agardh 1817, p. xxxv

6 Isthmosira Kützing (1845, p. 140) is the name for a genus of desmids and was probably written in error for Isthmia .

The Kinker catalogue lists six slides (* in Table 3) for quinquelocularis along with one addition slide for the invalidly published ‘ Biddulphia elongata ’ Meneghini (in Kützing 1849, p. 137, BM 19394), also considered a synonym of B. quinquelocularis . Although the Canary Islands are listed in Kützing (1844), no slide has Biddulphia quinquelocularis indicated as present. ‘Kützing 821’ is the source material for BM 19392, the apparent type material for B. quinquelocularis ( Figs 8–10).

BM Kützing Name Locality

“In der Nordsee, selten bei Helgoland!” Y

19391* 1778 quinquelocularis “häufiger an den britischen Inseln: Berkeley” [Ilfracombe, Ralfs] [ Ralfs 1843]; Y

BM001167210, https://data.nhm.ac.uk/dataset/collection-specimens/resource/

05ff2255-c38a-40c9-b657-4ccb55ab2feb/record/8288381).

19392* 821 quinquelocularis “Im mittelländischen Meer bei Genua!” 1 Y

“An den Küsten der kanarischen Inseln” Y

“bei der Insel Cuba ” [ Ehrenberg 1843] Y

19396* 8222 quinquelocularis Adriatic [Dalmatia, Croatia], BM001167212, https://data.nhm.ac.uk/dataset/ ‘dalmatica’ collection-specimens/resource/05ff2255-c38a-40c9-b657-4ccb55ab2feb/ record/8288390

19388* 933 quinquelocularis Lessina, Nolte [ Germany] ( Figs 17–19)

‘quinquelobata’

19394 9274 ‘elongata’ Adriatic [Dalmatia, Croatia]

19389* 887 quinquelocularis New York

‘quinquelobata’

19393* 1180 quinquelocularis Iles Chausey , France [5] ( Figs 13–16); BM001167209, https://data.nhm.ac.uk/ object/e009b8c3-8971-4099-922f-6f6f555a01ad).

1 On the slide label: “Genoa 1828”

2 No coverslip or specimens

3 Given as 937 in error.

4 W has specimens from ‘Kützing 936’ (W0088953), not present in BM. These are specimens of Biddulphia quinquelocularis from

Dalmatia, Croatia. They have not been examined.

5 https://websites.rbge.org.uk/algae/collections/ Biddulphia _WalkerArnott_Foreign_1.jpg

‘ Biddulphia elongata ’ Meneghini has only been recorded by Kützing (1849, p. 137) but Meneghini did comment earlier on the specimens: “Abbiamo nell’Adriatico le due specie quinquelocularis e trilocularis . Lo riferisco alla seconda una forma a bacilli minori e molto allungati, che credevo dapprima una nuova specie e come tale comunicai al Kützing, il quale la credette invece appartenente alla quinquelocularis ” ( Meneghini 1846, p. 1998). ‘Kützing 927’ is the source material for BM 19394, the apparent type material for ‘ B. elongata ’, which contains just fragments, mostly with fragments of a species of Rhabdonema ( Figures 11, 12, BM001167211: https://data.nhm.ac.uk/dataset/collection-specimens/resource/05ff2255-c38a- 40c9-b657-4ccb55ab2feb/record/8288389).