Callitriche cribrosa Schotsman (1965: 317)

Lansdown, Richard V., Rhazi, Laila, Saber, Er-Riyahi, Madihi, Mohammed El & Grillas, Patrick, 2022, The genus Callitriche (Plantaginaceae, Callitricheae) in Morocco, Phytotaxa 555 (1), pp. 53-72 : 58

2. Callitriche cribrosa Schotsman (1965: 317)

Type:— MOROCCO. In Atlantis majoribus montibus supra oppidum, Amismiz, 27 June 1925, R. Maire s.n. ( RAB 9647 ) .

Distribution:— Callitriche cribrosa occurs in the Iberian Peninsula, where it is more frequent in the south ( CSIC 2009), in Algeria ( Schotsman 1965), and in Morocco, it has also been reported from Italy ( Conti et al. 2005, Prančl et al. 2020). In Morocco, C. cribrosa is frequent from the coast to the Central Plateau and the Middle Atlas, from Rabat north-east to Fez and south to Ouarzazate, with isolated records from near Marrakesh and Tangiers ( Fig. 1C ).

Habitat and ecology: — Callitriche cribrosa typically grows in flowing waters of ditches, streams and river backwaters. It will tolerate nutrient enrichment, but at Oued Tizguite it appeared to have been eradicated from the main channel by excessive trampling by stock, persisting only in the spring, which was protected from stock access by a small wall. In Morocco, C. cribrosa has been recorded mainly with species typical of permanent waters such as Lemna gibba von Linné (1753: 970) , Nasturtium officinale Brown (1812: 110) , Ranunculus penicillatus ( Dumortier 1863: 216) Babington (1874: 7) subsp. pseudofluitans ( Syme 1863: 20) Webster (1988: 20) , and Veronica catenata Pennell (1921: 37) . In the spring at Oued Tizguite it also occurred with a rhodophyte [ Batrachospermum Roth (1797: 37) sp. ], which typically occurs in cold waters (N. Willby, pers. comm. 2005).

Recognition: — Callitriche cribrosa can be distinguished from other Callitriche species recorded from Morocco, except C. stagnalis , by the combination of the large, broadly winged fruit that are greyish-brown when mature, and large anthers with yellow pollen. It can often be distinguished from C. stagnalis by the broad floating leaves with more than seven parallel veins, however when this character is lacking it can only reliably be distinguished by the cribrose testa of the fruit.

Illustrations: —Figures in Lansdown [2008: 24 (7-7x), 87, 89].

Specimens examined: — MOROCCO: In Atlantis Majoris montibus supra oppidum Amizmiz: in aquis lente fluentibus. 27 June 1925, R. Maire s.n. ( RAB 9647 ) . Maaziz , 1 March 1931, J. Sallefom s.n. ( RAB 9666 ) . Plateau centrale ( Zaïane ), piste ‘ El-Khabonata à Sidi, ruisselet un peu à l’w de la cote 605 m, 17 April 1969, J. Mathez 4738 ( RAB 44754) . Entre Azrou et Ifrane, dans un ruisseau, 1970, Andreas, Schotsman 24 ( RAB 44642) . Source Cherrate , 1970 Mathez, Andreas, Schotsman 30 ( RAB 4465 , RAB 44646) . 1 km south of Maulay S. Aglibal dans un ruisseau, eau limpide, courante, 1970, H.D. Schotsman 19 (RAB 44638, RAB 44639) . Region de Rabat , petit ruisselet au S. Rzouk, Tiflet - Maaziz, au sud de Tiflet, 2 March 1970, H.D. Schotsman 8 ( RAB 44647) . Plateau centrale, Zaïane, Reg de Tsili - Oued Jouf au pied des falaises; ruisselet calme, 31 March 1970, J. Mathez 5221 ( RAB 40274) . In river , about 13 km SE of El Ksiba along road from El-Ksiba to Imilchil , by El Arba, Rabat, 5 July 1997, S.L. Jury 17501 ( RNG 12586) . High Atlas , 1300 m, 10 May 2010, G. Pils s.n. (herb. G. Pils) .

Field records: —Oued Tizguite and Oued Ouaslane, 902 m, 8 June 2019, R.V. Lansdown, N. Fetnassi, I. Mostakim.

Figures

FIGURE 1. Known distribution of Callitriche spp. in Morocco. A. C. brutia subsp. brutia, with insert map showing the position of Morocco in northwestern Africa. B. C. brutia subsp. naftolskyi. C. C. cribrosa. D. C. lusitanica.