Anisotes comorensis (Lindau) T. F. Daniel

Daniel, Thomas F., 2014, Taxonomy of nisotes Nees (Acanthaceae: Justicieae) in the Comoros Archipelago and a preliminary list of canthaceae in the Islands, Candollea 69 (1), pp. 45-54 : 50-51

Anisotes comorensis (Lindau) T. F. Daniel , comb. nova.

÷ Himantochilus comorensis Lindau in Bot. Jahrb. Syst. 20: 61. 1894.

Lectotypus (designated here): COMOROS. Grande Comore: s.l., VII.1886, Humblot 1584 ( P [ P00184832 ]!; iso-: LD [ LD1212195 ] image seen, P [ P00184831 , P00184833 ]!).

Perennial to 3.5 [or more?] dm tall. Older stems not seen; younger stems pubescent with flexuose to retrorse eglandular trichomes 0.2-0.5 mm long, trichomes ± evenly disposed or becoming concentrated in 2 lines. Leaves petiolate, petioles to 45 m long, blades membranaceous, ovate to elliptic, 60- 102 mm long, 22-37 mm wide, 2.1-2.8 X longer than wide, cuneate to subattenuate at base, acuminate at apex, major veins ± prominent, secondary veins 5-7 per side, surfaces pubescent with antrorse to flexuose eglandular trichomes. Spikes axillary, mostly opposite at leaf nodes, (1-)2-4 per axil, densely bracteate, pedunculate, peduncles 3-16 mm long, pubescent like young stems, fertile portion of spike (excluding corollas) 10-22 mm long, rachis not visible, puberulent with mostly erect eglandular trichomes to 0.1 mm long. Bracts light colored, imbricate, 4-ranked (2 adjacent rows fertile; thus ± secund), membranaceous, elliptic, 6-8.5 mm long, 2.5-4 mm wide, acute- to acuminate-apiculate at apex, apiculum 0.3-1 mm long, abaxial surface sparsely pubescent with antrorse to flexuose eglandular trichomes and with an inconspicuous understory (sometimes absent) of sessile to subsessile glands to 0.05 mm long, major veins evident but not conspicuous, 5, subparallel to midvein, margin sparsely ciliate with erect to flexuose eglandular trichomes 0.1-0.3 mm long, proximal pair of bracts sterile and often smaller (4-5.5 X 2.2-3.2 mm) than fertile ones. Bracteoles lanceolate, 4-5 mm long, 0.3-0.5 mm wide, abaxial surface pubescent like bracts to nearly glabrous, only midvein evident, margin ciliate like bracts. Calyx 5-lobed, 5.5- 7 mm long, tube 0.5-1 mm long, lobes lanceolate, 4.5-6 mm long, subequal in length (posterior lobe smallest), 0.5-0.7 mm wide, long-aristate at apex (aristae to 2 mm long), abaxially pubescent like bracts to nearly glabrous, margin not noticeably hyaline, ciliate. Corolla color unknown, 20-24 mm long, externally pubescent with erect to flexuose to retrorse eglandular trichomes 0.1-0.3 mm long, tube slightly and gradually expanded from near base to mouth, 8.5-11 mm long (0.43- 0.55 X as long as corolla), 1.5-2.5 mm in diameter near midpoint, upper lip 10-13 mm long, entire at apex, lower lip 10-11.5 mm long, recurved to recoiled, lobes 1.5-2.2 mm long, 0.5-2 mm wide. Stamens inserted near apex of corolla tube, 10-13 mm long, not extending beyond upper lip of corolla, filaments pubescent proximally and glabrous distally, thecae parallel to subperpendicular, unequally inserted (overlapping by 0.8-1 mm), 1.5-1.8 mm long (proximal theca slightly longer than distal theca), glabrous, distal theca usually with an inconspicuous basal appendage to 0.1 mm long, proximal theca with a basal appendage 0.3-0.4 mm long. Pollen 2-colporate, 4- pseudocolpate, globose-elliptic, polar diameter (P) 36-37 µm, equatorial diameter (E) in apertural view 23 µm, equatorial diameter in interapertural view 17 µm, P:E in apertural view = 1.57, P:E in interapertural view = 2.18, longer E:shorter E = 1.35, exine bireticulate. Style ca. 18-21 mm long, not or but barely extending beyond upper lip of corolla, pubescent proximally, stigma inconspicuous, lobes (if present) not evident. Capsule and seeds not known.

Phenology. – Flowering in July.

Distribution and habitat. – Comoros Archipelago; endemic to Grande Comore island ( Fig. 1 ); the species is known only from the type collection made in 1886 from an undisclosed locale.

Discussion. – There are three specimens at P, one annotated (recently) as the holotype and two as isotypes. No herbarium of deposit was cited in the protologue, and Humblot’s collections were widely distributed (LANJOUW & STAFLEU, 1957) including to B, where Lindau worked on Acanthaceae after 1892. If a single specimen at B was used by Lindau in creating his protologue, it would have been the holotype. Such a specimen is no longer extant at B. The specimen at P annotated as the holotype bears Lindau’s name in a handwriting that resembles that of Benoist rather than that of Lindau, and would thus appear to represent either a syntype or an isosyntype. This specimen (Humblot 1584 [P00184832]), which also bears the unpublished combination attributed to Benoist, is here designated as lectotype of Himantochilus comorensis .

LINDAU (1894) indicated that H. comorensis could be distinguished from its congeners by the shape of the leaves and the much smaller flowers. BADEN (1981b) treated Lindau’s H. comorensis as a “doubtful taxon”, did not see the type, and noted that based on Lindau’s description it was unlikely to pertain to Anisotes . Although Anisotes is not well distinguished morphologically from Justicia ( DANIEL & al., 2007; DANIEL & al., 2013), Lindau’s species contains the characteristic floral attributes of the former genus: relatively large (22-65 mm long) and strongly bilabiate corollas with ascending cochlear aestivation, a relatively short corolla tube (tube: corolla length up to 0.56, but usually 0.33 or less), a hoodlike and internally rugulate upper lip, and a lower lip that is usually recoiled.

Pollen of this species ( Fig. 2 ) is two-colporate with two pseudocolpi in each mesocolpium. Similar pollen was noted in Anisotes subcoriaceus T. F. Daniel, Letsara & Martín-Bravo from Madagascar ( DANIEL & al., 2013).

Figures

Fig. 1. – Comoros Archipelago (Union of the Comoros and Mayotte) showing distributions of Anisotes comorensis (Lindau) T. F. Daniel and A. mayottensis T. F. Daniel. The exact location of the sole collection of A. comorensis (Lindau) T. F. Daniel from Grande Comore is unknown.

Fig. 2. – Pollen of Anisotes Nees in the Comoros Archipelago. A-B. Anisotes mayottensis T. F. Daniel; C-D. A. comorensis (Lindau) T. F. Daniel; A. Apertural view; B. Interapertural view; C. pertural view; D. Interapertural view. [A-B: Pascal 936, CS; C-D: Humblot 1584, P]