r9821 ESSIG:GULUBIA Principes, 26(4), 1982, pp. I59-I?3 A Synopsisof the GenusGulubia FRnoeRrcrB. Essrc Department ofBiology, flniuersity ofSouth Flnrida, Tampa, FL 3362O Gulubia is a genus of nine known tandrous genera, petals of the pistillate species in the Areca alliance of palms. flowers have long, tapered tips ihat are The genus is distributed from the Moluc- closed over the stigma at the time the cas in Indonesia to the Palau Islands, New inflorescence opens. Staminate anthesis is Guinea, the Solomon Islands. the New first (though not immediate), with pistillate Hebrides, Fiji, and Australia. All are soli- anthesis following sometime later (details tary, moderate, elegant palms with prom- of timing have not been observed). inent crownshafts and clean tmnks. Two The present account summarizes what species have leaves with essentially straight is known about Gulubia, but is clearlv rachises and pendulous pinnae (Figs. 1- preliminary in nature. Specimens avail- 2), while the remaining species have able for most species are meager and there strongly arched leaves with erect pinnae is much that is not known. A large part (Figs- 3-8). These palms are eminently of the range of the genus has not been suitable for cultivation in the tropics, but adequately explored for palms, so new have not yet been widely planted. They species may come to light in the future, seem to have little economic use, but in just ag two new speciesare described here. New Guinea at least are used for floor- It is hoped that this paper will stimulate boards and sometimes for siding on build- the further exploration that is needed. ings. The genus is closely related to Grono- Fruit phyllum, Hyd.riastele, and Nengella, with Structurein Gulubia which it forms a natural subunit of the The structure of the pericarp has been Areca alfiance (Essig and Young 1979). found to be of considerabletax;nomic sis- From Hydriastele, Gulubia is separated nificancein the arecoidpalrns (Essig 1928, only by its emergent, solitary rathlr than Essigand Young l97t), so a spe;ial sec- caespitose habit. Inflorescence and flowers tion on the fruit of Gulubia is included are essentially indistinguishable. However here. The known speciesof Gulubia share it seems useful to provide an account of several basic features: a prominent pali- these distinctive emergent palms, even sade layer derived from the locular epi- though their generic status may hav'e to dermis, a series of fibrovascular bundies be reviewed in the future. From Grono- of varioussizes and shapes,a prominent, phyllum and, Nengella, Gulubia and dense zone of tanniniferous parenchyma, Hydriastele are disiinguished by a pro- and a subepidermal zone of compr;ssed togynous rather than protandrous mode of parenchyma. There are no sclereids or flowering and related morphology. In the crystalsin the outer pericarp, featuresthat p.rotogynous genera, pistillate petals are are commonin other arecoidDalms. short and the stigma is exposed it the time Representativesof all nine speciesof the inflorescence - opens. Pistillate anthesis Gulubia were examined using standard is immediate and staminate anthesis fol- histologicaltechniques (see Es-siglg7B). lows in 24 hours (Essig l9Z3). In the pro- Eight speciesare illustrated. Preparations PRINCIPES lVoL. 26 L. Gulubia moluecana,cultivated at Bogor (from Beccari,Am. Jard. Bot. Buitenzorg2, plate 7. 1885)' 2. Gulubia costdta' in lowland forest near the Frieda River' from dried material of Gulubia pct'lauensis tion of bundles (Fig. 9), which may be taken as. a more generalized condition were not adequate for drawing, but some 'n information was obtained, which will be probably ancestral to that G. costata. summarized below. 2. Gulubia longispatha can be char- Variation in fruit structure.is striking acterized by the presence of a distinct at every level, including the subspecific, series of fibrous bundles located outside of so detailed conclusions about the fruit the tanniniferous zone and apparently not structure in particular species cannol be connected with the fibrovascular bundles made based on limited samples. This is to the inside of the tanniniferous zone (Figs' iflustraled in the specimens of Culubia t 2-r4). longispa.tha, taken from three widely 3. Gulubia ualida appears to be most separated populations (Figs. l2-14). The similar to G. longispatha, bur lacks the following tentative remarks do seem to be outer series of fibrous bundles' and has a warranted however: broader zone of non-tanniniferous paren- I. Gulubia costdta clearly stands out chyma between the fibrovascular bundles because of the presence of very large and the tanniniferous zone (Fig. ll). fibrovascular bundles, alternating with 4. Gulubia hombronii and G. cYlin- much smaller ones, that give the fruit a drocarpa appear to be very similar in their ribbed appearance (Fig. l0). Gulubia fruit structure (Figs. 15 and l8). nith the moluccana clearly lacks this differentia- latter species apparently having smaller, l 9821 ESSIG:GULUBIA 3. Gulubia long^ispatha, growing +' culubia on the slopes of Mt. Suckling. rongispatha'type prant oi i. u^*li,t "irBella vista,c""oJn"u*"l photoby L. H. Brass, s. Gutuu toto nffi;t":i",T"T:'#,fiiT:XT;" FriedaRiver . 6. Culubia ualida, from the Torricelli Mourtalr, 1typ"il;j. PRINCIPES lVoL. 26 7. Gulubiahombronii, Santa Ysabel Island. Photo 8. Gulubia microcarpa,Viti Levu, Fiji Islands. by H. E. Moore,Jr. (courtesyL. H. BaileyHorto- Photoby H. E. Moore,Jr. (courtesyL. H. Bailey rium). ' Hortorium). more numerous and crowded fibrovascu- lar bundles. This difference may not be pericarp similar Io G. microcarpa, btrl reliable however as it is based on only one with a much thicker locular epidermis, well specimen from each species. developed as a palisade layer. There is no 5. Gulubia macrospadix is distinctive, sisn of fibrous bundles external to the tan- nol only in having ruminate endosperm. niniferous zone (not illustrated). but also in having a series of fibrous bun- In summary, it appears that each dles in mid-periclrp, which apiears to be species of Gulubia possessesdistinctive distinct from the fibrovascular system' but features in the pericarp, and isolated fruits not"as widely separated as in G. longis- might be identifiable. Subspecific variation patha. The fibrous bundles interrupt the appears to be significant, in at least one tanniniferous zone rather than being specieshowever, and this may confuse the external to it (Fig. 16). Also, the locular picture. Ultimately, pericarp structure may epidermis is wavy, following the uneven prove to be a sensitive marker for affini- contours of the seed. ties at the subspecific and population level. 6. Gulubia microcarpa has the thin- nest pericarp of all species, with markedly TaxonomicTreatment flattened fibrovascular bundles, and a locular epidermis only slightly modified in Gulubia Beccari in Ann. Jard. Bot. Bui- the direction of a palisade layer (Fig. l7). tenzorg2: l2B, l3l. 1885; Beccariin 7 . Gulubia palauensis, viewed in dried Martelli, Nuov. Giorn. Bot. Ital. ll, 42: material from Tuyama s.n., has a thin 84. 1935; Beccariand Pichi-Sermolli t9821 ESSIG:GULUBIA o ta I O a a O 12 10 r3 Epidermls Tshniniferous cetle Fibroua bundlea Fibrovascular bundl6s -1J Locular, €pidermis Figures 9-14. Diagrams of typical segmentsof the pericarp in cross-section. 9. Gulubia moluccana, from Beguin 2098. I0. Gulubia costata, from Essig s.n. (Brahman River area, Madany Province). lI. Gulubia aalida, ftom EssigLAE 55099. 12. Gulubia longispatha, from Essig LAE 55231(Mt' Suckling, Milne Bay Province). 13. Gulubia longispatha from Brass 5457 (Central Province). 14. Gulubia longispatho, from DssJgLAE ($test Sepik Province)' PRINCIPES lVoL. 26 l5 Figures l5-I8. Diagrams of typical segmentsof the pericarp in cross-section. t5. Gulubia hombronii, from Moore & Witmore 9296. 16. Gulubia macrospadix, from Moore & Whitmore 9305. 17. Gulubia microcarpa, from Moore & Phillips 1O543. 18. Gulubia cylindrocarpa, from Raynal 16256- in Webbia ll: 40. 1955; Moore & scars; crownshaft well-developed; leaves Fosbergin GentesHerb. B: 455. 1956; reduplicately pinnate; sheath tubular, Moorein CentesHerb. 9: 263. 1963: elongate, cylindrical; petiole short, almost Moorein PrincipesI0: BB. 1966. Type flat or concave adaxially, convex abaxi- species:Gulubia moluccana (Beccari) ally; rachis straight or moderately to Beccari (seeBeccari & Pichi-Sermolli, strongly arcuate, pinnae regularly op. cit.). arranged, pendulous or horizontal to Kentia Blume in Bull. Sci. Phys. Nat. ascending, sometimes upper Ieaflets Neerlande l: 64. lB3B (i4 part, see recurved and drooping, linear-lanceolate, Moore in Gentes Herbarum 9: 264. unicostate, acute or notched at the apex, 1963); Beccari,Malesia 1: 36. 1877. sometimes with prominent ramenta on the Type: Kentia moluccana Beccari lower surface; leaf axis densely brownJep- Gulubiopsis Beccari in Bot. Jahrb. Syst. idote-tomentose to minutely brown-dotted. 59: lI. 1924; Beccari & Pichi-Ser- Inflorescence infrafoliar, solitary at each molli in Webbia 1l: 40. 1955. Type: node, but often several in different stages C. palauensisBeccari of flowering and fruiting at one time. pan- Paragulubia Burret in Notizbl. Bot. Gart. iculate, branching to l-3 orders, pedun- Mus. Berlin-Dahleml3: 84. 1936; cle short, often becoming bulbous in fruit, Beccari & PichiSermolli in Webbia I l: prophyll compressed, broadly oblanceo- 46. 1955. Type: P. macrospadixBtr- late, completely closed around the bud, ret. rounded at the tip, second peduncular Tall, solitary, unarmed,