Riccardia longispica (Steph.) Pearson

Reeb, Catherine & Gradstein, Robbert, 2020, A taxonomic revision of Aneuraceae (Marchantiophyta) from eastern Africa with an interactive identification key, Cryptogamie, Bryologie 20 (2), pp. 11-34 : 24-26

Riccardia longispica (Steph.) Pearson

( Fig. 3 L-W)

Aneura longispica Steph. , Botanical Gazette 15: 281 (1890). —

Type: Réunion, Boivin s.n. ( G [ G 00067568]!).

Aneura congoensis Steph. , Species Hepaticarum 6: 23 (1917). — Type: Congo ( Reeb & Bardat 2014).

Aneura grosselimbata Steph. , Species Hepaticarum 6: 29 (1917). — Type: Tanzania ( Reeb & Bardat 2014 as R. limbata ).

Aneura holstii Steph. , Species Hepaticarum 6: 31 (1917). — Riccardia holstii (Steph.) E.W.Jones, Transactions of the British Bryological Society 3: 78 (1956). — Type: Tanzania ( Reeb & Bardat 2014 as R. limbata ).

Aneura lepervanchei Steph. , Species Hepaticarum 1: 255 (1899). — Type: Réunion ( Reeb & Bardat 2014).

Aneura limbat a Steph., Hedwigia 30: 204 (1891). — Riccardia limbata (Steph.) E.W.Jones, Transactions of the British Bryological Society 3: 79 (1956). — Type: Cameroon, Lower Bomania, 1890, Dusén 33 (lecto-, here designated, G[G00067566]!) syn. nov.

Aneura piliflora Steph. , Species Hepaticarum 6: 38 (1917). — Type: Madagascar ( Jones 1956).

Aneura reticulata Steph. , Hedwigia 30: 204 (1891). — Riccardia reticulata (Steph.) S.W. Arnell, Botaniska Notiser 1952: 152 (1952). — Type: Cameroon ( Jones 1956 as R. limbata ).

Aneura erosa Steph. , Hedwigia 30: 269 (1891). — Riccardia erosa (Steph.) E.W.Jones, Transactions of the British Bryological Society 3: 83 (1956). — Type: Sao Tomé, 1989, Quintas 7 (G[G0067552]!) syn. nov.

Aneura tenera Steph. , Species Hepaticarum 6: 43 (1917). — Type: Tanzania ( Reeb & Bardat 2014) syn. nov.

? Riccardia kilimanjarica S.W.Arnell., Svensk Botanisk Tidskrift 53: 543 (1959). — Type: Tanzania ( Reeb & Bardat 2014).

SELECTED FURTHER SPECIMENS EXAMINED. — Central AFrica Republic. Plateau de Kagadouba, 480 m, Assel 729 (E00018738, EGR).

Comores. Karthala, 2010, Bardat Karp1q2li2 * ( PC 0763850).

Congo. Kimpese, road Lombo Fuese, 5°23’52”S, 14°28’12”E, 640 m, 13. I.2013, Vanderpoorten 13111*.

Equatorial Guinea. Evinayong, Mt. Alen, 950 m. 25.VII.1994, Heras VIT 398/94*.

Ethiopia. Bonga, Gera Beki forest, 37°80’82.07”N, 19°96’66”E, 1881 m, 12.XII.2006, Hylander KH 5488*, KH 5491* ( ETH, PC 0763858).

Gabon. Ogoué-Ivindo, Réserve intégrale d’Ipassa, 00°30’N, 12°48’00”E, 510 m, 01.IV.06, Vanderpoorten GAB 1396*, 03°04’8”N, 12°46’12”E, 11.IV.06, Vanderpoorten GAB 1398*.

Ghana. Central region, Pra-Suhien Forest Reserve, 11.II.1971, Jones 1339 A ( E 00018734, G 00264219).

Madagascar. Alaotra-Mangoro, Vohimana Reserve, 18°55’24.2”S, 48°30’21.1”E, 860 m, 14.IV.2010, Reeb, Andriamanantena, & Bidault CRAE 74 * ( PC 0724433 B), 18°55’43.6”S, 48°29’56.6”E, 849 m, 15.IV.2010, Reeb, Andriamanantena, & Bidault CRAE 84 ( PC 0724365), CRAE 88 * ( PC 0763869), 18°55’13.1”S, 48°30’57.1”E, 789 m, 29. VI.2012, Reeb MTV1225 * ( PC 0763889), MTV1226 ( PC), 18°55’45.7”S, 48°29’59.3”E, 918 m, 30. VI.2012, Reeb MTV1234 ( PC 0763887), MTV1237 *( PC 0763888), MTV1238 ( PC 0763892); Alaotra-Mangoro, Maromizaha Réserve, 18°59’S, 48°28’E, 1084- 1095 m, 07.VII.2012, Reeb MTM12103 * ( PC 0763854), MTM12106 * ( PC 0763855); Antsiranana, Manongarivo Special Reserve, 13°59’S, 48°26’E, 1300-1350 m, Geissler 19708/5 ( G); Sava, Parc du Marojejy, 29.XI.2009, Bardat JBMAD 104 * ( PC 0763861), Makirovana, 14°10’29.3”S, 49°57’07”E, 695 m, 06. V.2010, Reeb CR 276 ( PC 0763841), CR 288 ( PC 0763836 A), 14°17’10.04”S, 49°57’07.5”E, 508 m, 07. V.2010, Reeb CR 304 * ( PC 0763833).

Malawi. Mulanje Mt., 15°53’21”S, 35°39’24”E. 2180 m, 25. VI.91, Longton M 8302 A * ( E), 15°55’01”S, 35°36’04”E, 2000 m, 24. VI.1991, Kungu M 3199 A * (E-00430533).

Mauritius. Mt. Le Pouce, 20°13’5”S, 57°31’20”E, 750-811 m, 20.III.1995, Pócs 9537 H * ( EGR).

Réunion. Cirque de Salazie, 21°2’50”S, 55°28’8”E, 1899 m, 24.VIII.1994, Szabo 9422 J * ( EGR); Plaine des Palmistes, 21°6’33”S, 55°39’E, 900 m, 30.VIII.1994, Vojko 9435 L * ( EGR); Forêt de Belouve, 21°2’S 55°33.5’E, 1440 m, 16.VII.1996, Konya 9644/D * ( G 00264189, EGR); Piton de la Fournaise, 21°18’08”S, 55°44’00”E, 1200 m, Szabo 9609/ CP * ( EGR), 21°18’05”S, 55°42’05”E, 1000- 1390 m, 30. VI.1996, Pócs 9612/CD ( EGR). Plaine des fougères, 1325 m, 19.IV2011, Bardat PF.2 ( PC 0763860).

South AFrica. Port Shepstone, Iberzana, 10 m, 23.VIII.1918, Eyles 1407 ( EGR).

Tanzania. Trail Kitoto to Meru crater, 2500 m, 11.VII.1968, Sharp et al. P 507 ( E 00018742, EGR); Mt. Kilimanjaro, trail Mweka to Kibo Peak, 2400-2800 m, 29.VII.1968, Sharp et al. 7632 ( E).

Uganda. Rukungiri, 1°00’00”S, 29°37’00”E, 1650 m, 07.II.1997, Wiggington U 8318 C *, U 8321 A, U 8324 A *.

PHENOTYPE EROSA. — Gabon. Province Ogououé-Ivindo, chutes de Kongou sur l’Ivindo 0°17’24”N, 12°25’18”E, 09.IV.2006, Vanderpoorten GAB 1435*.

Madagascar. Alaotra-Mangoro, Vohibola Reserve, 18°35’16.1”S, 49°14’28.8”E, 20.IV.2010, Reeb, Andriamanantena & Bidault CRAE 193 ( PC 0763859); Atsimo-Andrefana, massif du Makay, 21°34’05.9”S, 45°04’33.7”E, 303 m, 14. I.2011, Reeb CR 1126 * ( PC), 21°34’09.8”S, 45°04’35.4”E, 290 m, 16. I.2011, Reeb CR 1169 * ( PC 0763891), 21°38’53”S, 44°59’52”E, 189 m, 23. I.2011, Reeb CR 11126 * ( PC 0763894), CR 11127 * ( PC 0763895).

Tanzania. Usambara Mts., Amanani, 950 m, 17. VI.1970, Rasmussen & Esbessen B 27 ( EGR).

Uganda. Nyakafunjo Nat. Reserve, 24. I.1997, 1075 m, Porley U 416 A ( E), 1060 m, Hodgetts U 4346 A ( E); Kabale Bwindi Nat. Park, 01°23’7”S, 29°46’50”E, 2250 m, 25. I.1997, Hodgetts U 5009 A * ( E 00430552), 2415 m, 25. I.1996, Porley U 35 B * ( E 00430508).

DISTRIBUTION. — Riccardia longispica is one of the most common African Riccardia species, recorded from almost all West and East African countries and Indian Ocean Islands (Wigginton 2018).

HABITAT. — The large phenotype of R. longispica is mainly found on dead wood, sometimes on humid rock along streams or near waterfalls, or on dense bryophyte mats (in Réunion), between about 500 and 2500 m. The small erosa phenotype seems to have the same geographical distribution as the large phenotype but is mainly found on shaded lateritic soil, occasionally on rotten wood, and occurs at slightly lower elevation (200 m) on Madagascar.

DESCRIPTION

Dioicous, occasionally monoicous ( R. limbata , R. holstii ).

Thallus

Green to olive green when fresh, yellow to dark brown or green in herbarium, soft to fleshy, (10-) 20-30 mm long, very variable when dry, crisped (in phenotype erosa ) or flat, ultimate branches usually slightly recurved, main and secondary axes closely attached to the substrate from which arise the ultimate branches, branching 1-2(-3)-pinnate, sometimes palmate on young thalli, branches alternate or subopposite, reiterations sometimes present, stolons mainly seen in young thalli.

Main axis

Irregularly defined in young plants, well-defined in mature thalli, (600-)800-1200(-1400) µm wide, in cross section ellipsoid to biconvex at the base, plano-convex in the middle, 5-7(-8) cells high, margins acute, with narrow, 1-2 cells wide wings, epidermis cells at least 4-5× smaller than inner cells.

Primary branches

To 700 µm wide, occasionally overlapping.

Ultimate branches

Tongue-shaped to oblong, straight in well-developed thalli (stocky and fan-shaped in young thalli), 2.5-4.2 mm long, (0.4-)0.5-0.8(-1.0) mm wide, in cross section plano-convex to slightly concave-convex, 3-4(-5) cells thick, wings 2-4 cells wide, narrower than the midrib, epidermis cells usually in straight rows, rarely in diverging rows (obliquely to the axis), branch apex rounded to truncate with sometimes overlapping lateral edges.

Mucilage papillae

Ventral (in two rows) and apical, persistent.

Oil bodies

Present in all cells, spherical to ellipsoid to bean-shaped, finely granular, 1-2 per cell.

Male branches

Solitary, rarely grouped by two, along axis and branches, straight except when young, to 2 mm long, wing equal to narrower than the axis, scale-like, antheria in 6-12(-20) pairs.

Female branches

Ventro-laterally inserted, bordered by a scale-like, 1-2 cells wide wing, wing narrower than the axis, archegonia in 5-12 pairs.

Calyptra

To 2 mm long, terminating in a crown-like umbo and very scattered thick-walled cells armed with striations.

Gemmae

Occasionally present, especially at branch junctions, produced on deformed thallus margins, 2-celled.

eROSA PHENOTYPE ( Fig. 2 R-W)

Plants

Usually growing on lateritic soil.

Thallus

Very small, to 5-6 mm long only, 1-2-pinnate without reiterations, crisped when dry.

Main axis

180-320 µm wide, in cross section circular ellipsoid at the base to plano-convex in middle, 3-4 cells high, with 1-2 cells wide wings, epidermis cells 2-3× smaller than inner cells.

Ultimate branches

280-2000 µm long, 70-330 µm wide, linear to oblong, sometimes tongue-shaped, in cross section plano-convex, 3-4 cells thick, wings 3-4 cells wide, as wide as or wider than the midrib, wing cells in straight rows.

Sexual branches

Equal or longer than ultimate branches.

Male branches sessile

Or shortly stalked.

Figures

FIG. 3. — Riccardia gasparii Reeb & Gradst. sp. nov.: A, thalli; B, main axis in cross section; C, ultimate branches in cross section; D, male branch; E, female branches.From Reeb MTV1246 (PC0771050), MTM12134 (PC0763884). Riccardia inconspicua (Steph) Reeb & Bardat:F, thalli;G, portion of ultimate branch with papillae; H, branched papilla (arrow); I, ultimate branch and male branch with papillae; J, main axis in cross section; K, ultimate branch in cross section. From Reeb MTM1295 (PC0763882), Pócs & Mwanjabe 6464/BP, Gardiner s.n. (Type of Aneura exigua), Jungner s.n. (Type of Aneura inconspicua). Riccardia longispica (Steph.) Pearson: L, thalli; M, main axis in cross section; N, ultimate branches in cross section; O, two male branches; P, female branch; Q, male branch. From Konya 9644/D, Bardat PF.2 (PC0763860), Pócs 9612/CD, De Lisle 199 (Type), Jones 1542b. Riccardia longispica (Steph.) Pearson phenotype erosa: R, thalli; S,two calyptra’s; T, main axis in cross section; U, thallus mat showing erect, concave ultimate branches; V, ultimate branch in cross section; W, branch apex with papillae and immature gemmae. From Porley U35b, Pócs 6052/CV, Reeb CRAE193 (PC0763859). Scale bars: A, F, L, R, U, 1 mm; B, C, M-P, Q, S, 500 µm; D, E, G-K, T, 200 µm; H, V, W, 100 µm.

FIG. 2. — Riccardia angusticosta (Steph.) Grolle: A, thalli; B, main axis in cross section; C, ultimate branch in cross section; D, calyptra; E, upper portion of calyptra, showing umbo. From Thollon s.n. (Aneura stephanii TYPE), Pócs 9883/H, Brenan140. Riccardia chamedryfolia (With.) Grolle: F, thalli; G, portion of thallus showing male and female branches;H, main axis in cross section;C, ultimate branch in cross section.From Reeb CR11156 (PC0763897), CR11418 (PC0763898), Hylander KH5497 (PC0763862). Riccardia corbieri (Steph.) Reeb & Gradst. comb. nov.: J, thalli; K, main axis in cross section; L, ultimate branch in cross section; M, portion of thallus with female branch;N, ultimate branches and calyptra.From Beaver B304 (PC0763848), Reeb CR297 (PC0763838A),CR295 (PC0763837A). Riccardia fastigiata (Lehm.) Trevis.: O, thalli; P, main axis in cross section; Q, ultimate branches in cross section; R, portion of thallus with femalre branches and calyptra. From Vojko 9422/AP, Pócs 6929/T, Orban 9615/CB (PC0146833). Scale bars: A, D-F, J, M-O, R, 1 mm; B, C, G-I, K, 500 µm; L, P, Q, 200 µm.