Callitriche stagnalis Scopoli (1772: 251)

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 : 64-65

8. Callitriche stagnalis Scopoli (1772: 251)

Type: — UNITED KINGDOM. Cardiganshire. Aberleri Fields, Borth , Cards 22/61209160, 20 July 1998, A.O. Chater s.n. (neotype [designated by Lansdown (2006: 108)]: NMW!) .

Distribution: — Callitriche stagnalis is a predominantly European species, occurring east from Norway into Russia and south to Greece and Turkey, but rare in the east and has not been confirmed from the Levant or North Africa east of Morocco. The limits of its distribution have been obscured by frequent and widespread mis-identification. It is widespread and abundant throughout the Iberian Peninsula, but in Morocco is known only from the Central Plateau and the Rif, where it is frequent ( Fig. 4C ).

Habitat and ecology: — Callitriche stagnalis occurs in a wide range of habitats, most often on wet tracks in woodland, in pools in pasture, lake and river margins, and the margins of ditches. In Morocco it has been recorded from reservoirs and ponds, as well as cupular pools in granite, wet flushes, and streams. It occurs with a wide range of species and records from Moroccan populations include 23% that may be considered truly aquatic, 38% typical of marginal habitats or seasonal wetlands, and 39% terrestrial, reflecting its occurrence in both seasonal and permanent wetlands. Typical associates in Morocco include Anthoxanthum odoratum von Linné (1753: 28) , Callitriche brutia subsp. naftolskyi , C. mathezii , C. regis-jubae , Eleocharis palustris , Fontinalis Hedwig (1801: 298) sp. , Helosciadium nodiflorum , Hordeum murinum von Linné (1753: 85) , Juncus bufonius , Lemna gibba , Lythrum hyssopifolia , Mentha pulegium von Linné (1753: 577) , Mentha suaveolens Ehrhart (1792: 149) , Nasturtium officinale , Nerium oleander von Linné (1753: 209) , Plantago coronopus , Poa annua von Linné (1753: 68) , Polypogon monspeliensis Desfontaines (1798: 67) , Potamogeton nodosus , Pulicaria arabica , Ranunculus ophioglossifolius , R. peltatus , Scrophularia auriculata , and Veronica catenata . Elevation in Morocco: 0–1560 m.

Recognition: — Callitriche stagnalis can be distinguished from other Callitriche species recorded from Morocco except C. cribrosa , by the combination of the large fruit that are greyish-brown when mature, and large anthers with yellow pollen. It can only reliably be distinguished from C. cribrosa by the looped testa of the fruit, however most healthy plants of C. cribrosa will have leaves with more than seven parallel veins, whereas the leaves of C. stagnalis have fewer veins.

Illustrations: —Figures in Lansdown [2008: 24 (6–6x), 81, 83] and in Lansdown (2022: Fig. 10j).

Specimens examined: — MOROCCO: Stream , Asmismis, s.d., N.D. Simpson 36.378 ( BM) . Al-Hoceima. Izdad , 1 July 1993, J.A. Mejias, S. Silvestre s.n. ( RNG) . Barrage Smir , Tetouan. M’diq, 4 April 1994, J.M. Montserrat, B. Vales s.n. ( RNG) . Souk el Arba de Beni Hassim, 6 June 1994, M.A. Mateos, J.M. Montserrat s.n. ( RNG) . Larache , Ksor-el-Kebir , Orillas del rio Loukkos Arcillas, 30 m, 17 March 1995, M.A. Mateos, M.C. Reina, G. Sangalli, Sardóa, B. Valdés, 4783/95 ( RNG) . Wet flush on open west-facing slope, NE of Chefchaouen, track to Jbel Tassaout just above Talembote village , 21.4 km from main Tetouan to Chefchaouen, 595 m, 27 May 2002, S.L. Jury, M. Ait Lafikh, R. Brown, M.A. Carine & F.J. Rumsey 19371 (RAB 65458, RNG 27229) . Wet flush with Salix , just below spring, track down E of Mirador de Perdicaris , Prov. Tanger above Tanger, 26 May 2002, S.L. Jury, M. Ait Lafkih, R. Brown, M.A. Carine, F.J. Rumsey s.n. (RAB 65491, RNG 27154) . In village pond, turning off Oued Laou Valley along road by Oued Tassikeste and up track at Hamada Village, 7 June 2005, S.L. Jury, M. Ait Lafkih, R. Brown, M.A. Carine, F.J. Rumsey 199 ( RNG 44276) . Stream upstream of the Akalii dam, 28 April 2019, R.V. Lansdown, L. Rhazi, P. Grillas, M. El Madihi, J. Snoeks s.n. ( RAB) .

Field records: —Seasonal stream near Oulmès, 1170 m, 28 April 2019, R.V. Lansdown, L. Rhazi, P. Grillas, M. El Madihi, J. Snoeks. River near Oulmès, 30 April 2019, R.V. Lansdown, L. Rhazi, P. Grillas, M. El Madihi, J. Snoeks. Cupular pools in granite near Mante (Aguelmous), 1163 m altitude, 30 April 2019, R.V. Lansdown, L. Rhazi, P. Grillas, M. El Madihi, J. Snoeks. Sidi Mrahe stream, 1043 m, 30 April 2019, R.V. Lansdown, L. Rhazi, P. Grillas, M. El Madihi, J. Snoeks. Stream near Hotel des Thermes à Tarmilate (Oulmès), 28 April 2019, R.V. Lansdown, L. Rhazi, P. Grillas, M. El Madihi, J. Snoeks. Stream Tna Ounahal, 1129 m altitude, 30 April 2019, R.V. Lansdown, L. Rhazi, P. Grillas, M. El Madihi, J. Snoeks.

Figures

FIGURE 4. Known distribution of Callitriche species in Morocco. A. C. obtusangula. B. C. regis-jubae. C. C. stagnalis. D. C. truncata subsp. occidentalis. E. C. truncata subsp. truncata. F. All records of all Callitriche species in Morocco.