Orthiopteris campylura var. insularis P.H.Hovenkamp & T.T.Luong, 2015

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 : 49

d. Orthiopteris campylura var. insularis P.H.Hovenkamp & T.T.Luong var. nov. Figs 2i , 3i, j

Diagnosis.

Sori asymmetric, not protruding from the margin, <0.6 mm wide. outer indusium at one side strongly excurrent on lamina.

Type.

SOLOMON ISLANDS. San Cristoval, Hinuahaoro, alt. 900 m, 22 September 1932, Brass 2914 (holo: L, 0319881, iso: K, MICH).

Description.

Sori not protruding from the margin, not reflexed, in one plane with lamina wings, 0.8-1.0 × 0.5-0.6 mm, asymmetric, narrow obovate, widest just below mouth sori; inner indusium bright-brown, firm, usually shorter, sometimes equal to outer indusium, apex with 0.1-0.2 mm long lobe; outer indusium deeply emarginate, at one side strongly excurrent on lamina; sporangia 10-15 per sorus, capsule globose and rounded at apex, gradually narrowed toward base, indurated annulus cells 17-22, clearly unequal; spores not seen.

Distribution.

Papua New Guinea (Bougainville), Solomon islands, Vanuatu (Erromango).

Etymology.

The varietal epithet refers to the archipelagic distribution of this taxon.

Discussion.

This variety is quite widespread in the island archipelago stretching from Bougainville to the New Hebrides, but appears to be absent on the mainland of New Guinea.

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.