Orthiopteris cicutarioides (Baker) Copel., Univ. Calif. Publ. Bot. 18: 217. 1942.

Luong, Thien Tam, Hovenkamp, Peter H. & Sosef, Marc S. M., 2015, Revision of the fern genus Orthiopteris (Saccolomataceae) in Malesia and adjacent regions, PhytoKeys 53, pp. 39-71 : 51

2. Orthiopteris cicutarioides (Baker) Copel., Univ. Calif. Publ. Bot. 18: 217. 1942. Figs 2b , 3h , 4a

Davallia cicutarioides Baker, J. Bot. 28: 106 (1890)

Leucostegia? cicutarioides (Baker) C.Chr., Index Filic., Suppl. III: 120 (1934) Type. Based on Davallia cicutarioides Baker

Ithycaulon tenuisectum C.Chr., Brittonia 2: 285. 1937. Type. PAPUA NEW GUINEA. Central Division, Dieni, alt. 700 m, 01 May 1933, Brass 3139 (holo: BM n.v., iso: NY, 00127937*; MICH, 1190678*)

Ithycaulon cicutariodes (Baker) Alston, J. Bot. 77: 289. 1939. Type. Based on Davallia cicutarioides Baker

Type.

PAPUA NEW GUINEA. Mount Musgrave, alt. 700 m, 25 June 1889, W. Macgregor s.n. (Holo: K, 00794858*).

Description.

Rhizome erect, rising at least 2 cm above ground, diameter unknown. Rhizome scales pseudopeltate, ca. 3.0 × 1.0 mm, lanceolate with long falcate acumen. Fronds 90-110 × 30-50 cm; stipes stout, 35-45 cm long, 0.4-0.5 cm across (at base), light brown; lamina deltoid, tripinnate to quadripinnate, ca. 70 × 30-50 cm, papyraceous, yellow-green when dry, glabrous or with few scattered scales; pinnae at 40-45° to rachis, largest at base, overlapping, stalk 2.0-2.5 cm, including stalk 25-35 × 10-15 cm, lanceolate, first basiscopic pinnules of lowest pinnae enlarged; ultimate segments 1.0-2.0 × 0.5-0.7 cm, sessile or very short stalked, trapeziform, apex acute, margin with weak cartilaginous border; deeply incised to less than 0.2 mm from veins; lobes oblanceolate, veins in lobes unbranched or with 1 fork, light brown and not strongly contrasting with lamina, percurrent. Scales on rachis mostly present at base of segment, hair-like. Sori apical on small lobes, lateral on larger lobes, symmetric, not reflexed, slightly concave with lamina wings slightly recurved, 0.7-0.8 × 0.4-0.5 mm, wide obovate, widest just below mouth, not wider than the lamina below sorus; inner indusium brownish, firm, shorter than outer indusium, apex with c. 0.1 mm long lobe; outer indusium truncate-obtuse.

Distribution.

Papua New Guinea (Boridi).

Ecology.

Terrestrial, at 700-1500 m altitude.

Discussion.

Orthiopteris cicutarioides has the least dissected fronds in the group of finely dissected-frond species, with usually more than one vein per lobe. The single specimen of this species that could be examined had sterile sori without sporangia, which might be an indication of a hybrid origin. The shape of the sorus and indusium of Orthiopteris cicutarioides resembles those of Orthiopteris campylura var. caudata , and it could represent a locally derived taxon.

Figures

Figure 2. Ultimate segments. Arrows show distance from base of the shallowest sinuses to nearest costule / vein. a Orthiopteris ferulacea, Smith 8932 (K) b Orthiopteris cicutarioides, Carr 13257 (K) c Orthiopteris samoensis, Reinecke 97 a (L) d Orthiopteris trichophylla, Brass 12239 (L) e Orthiopteris campylura var. cautada, Carr 12518 (L) f Orthiopteris campylura var. laxa Mueller s. n. (L) g Orthiopteris campylura var. kingii, Brass 12941 (MICH) h Orthiopteris henriettae, Lam & Meeuse 5892 (L) i Orthiopteris campylura var. insularis Braithwaite 4110 (L). All scale bars 1 mm.

Figure 3. Sori of Orthiopteris seen from abaxial side. a, b Orthiopteris campylura var. campylura (Cuming 119, MICH) c Orthiopteris campylura var. kingii (Brass 12941, MICH) d Orthiopteris trichophylla (Brass 12239, L) e Orthiopteris tenuis (Smith 9154, L) f Orthiopteris tenuis (Smith 7274, L) g Orthiopteris campylura var. caudata (Carr 12518, L) h Orthiopteris cicutarioides (Carr 13257, K) i, j Orthiopteris campylura var. insularis (Braithwaite 4110, L) k Orthiopteris tenuis (small segment) (Degener 14648, L) l Orthiopteris ferulacea (Smith 8932, K) m, n Orthiopteris firma (Schlechter 14890, L) o, p Orthiopteris campylura var. laxa (Mueller s. n., L) q, r Orthiopteris henriettae (Lam & Meeuse 5892, L) s Orthiopteris henriettae. t Orthiopteris samoensis (Reinecke 97 a, L) u, v Orthiopteris samoensis (Vaupel 312, L). All scale bars 1 mm, oi = outer indusium, ii = inner indusium.

Figure 4. a-d Rhizome scales and e-h rachis scales of Orthiopteris. a Orthiopteris cicutarioides (Carr 13257, L) b Orthiopteris ferulacea (Smith 8932) c Orthiopteris firma (Green 1793, K) d Orthiopteris campylura var. kingi (Hoogland & Craven 10162, L) e, f Orthiopteris campylura var. kingi (Larhing 6910, L) g, h Orthiopteris samoensis (Reinecke 97 a, L). Scale bars: 1 mm (a-d), 0.1 mm (e-h).