Chelonistele laetitia-reginae, a new orchid species from Sarawak

3 Pages·1996·0.58 MB·English

by  De Vogel, E F

BLUMEA 41 (1996) 23-25
Chelonistelelaetitia-reginae,
a new orchid species from Sarawak
E.F. deVogel
Rijksherbarium/Hortus Botanicus,Leiden,TheNetherlands
INTRODUCTION
Therevisionofthegenus ChelonisteleinOrchid Monographs 1(1986) 23-40lists
11 species and 4variations.All occur in Borneo, which is evidently thecentre of
speciation ofthis genus;only Chelonistelesulphurea var. sulphurea occurs inaddi-
tion in Java,SumatraandtheMalay Peninsula.During jointfieldwork in 1991with
staffoftheSarawakHerbariumintheHoseMountains,Sarawak,thepresentauthor
collectedherbariumand livespecimens ofmany orchids. Among theliveorchids
were quiteanumberofChelonistelespecies fromdifferenthabitats.Fifteenofthese,
belonging to six species, floweredinthe LeidenHortusBotanicus. Twoare common
andare well known from manyherbariumspecimens: C. sulphurea var. sulphurea
andC. amplissima. Threewere in 1986knownby afewspecimens only: C. inglorio
(7 specimens), C. unguiculata (3), and C. brevilamelluta(20). One species, in the
fieldrepresented byafewspecimens, appeared tobenewtoscience,andis described
here.
Chelonistele laetitia-reginae deVogel, spec.nov.
Flos hypochiliobrevi notatuslobislateralibus longisangustetriangularibuscarinisquebasi
altissimis ad unguis epichilii medio submittentibus ubi evanent; epichilio ungue longo
angustodesinente in lobum terminalem bene evolutum papilioniformemlobis laterilibus
irregulariter rectangularibus,columnae cuculli margineapicalidentibus 4 grandibustrian-
gularibusad angustetriangularibus.—Typus: Leiden cult, (de Vogel)913697(SAR holo;
L iso).
Plant36-45 cm high.Roots 0.7-1 mmdiam.Rhizomeshort, rhizome scales soon
desintegrating. Scales ofthe youngshoot7; smallestone 12-15mm long, largest
one 10-11.3cm long; nerves many, fine.Pseudobulbsclose together, slenderfusi-
form, 9-11.5 cm long, smooth, when driedwith finesharp longitudinal folds.Leuf
oneperpseudobulb, stiffherbaceous. Petioledeeply channelled, 4-9cm long. Blade
elliptic, 19-22(-28?) by 2.4-3.5 cm; topacuminate; midribprominent below, less
so above, mainadditionalnerves 4-6, slightly prominent aboveand below, small
nerves many, hardly prominent. Rdcemeproteranthous to synanthous withthe very
youngleaves,erect, curved, 7-9-flowered.Pedunclebeyond thescalesoftheyoung
shoot0.5-1 cm long, 2 mmdiam.Rhachis slightly zigzag, 5.5-6.5cm long; inter-
nodes7-10mm long.Floral bractspersistent, ovate, 14-27by 7-13mm;top acute;
nerves 17-27.Flowers widely open,somewhatfleshy. Pedicel c.5 by 1 mm;ovary
c.5 by 1.7 mm.Mediansepal elliptic, c. 13.5by 5.5mm;top rounded,retuse; mar-
24 BLUMEA —Vol. 41, No. 1, 1996
Chelonistelelaetilia-reginaedeVogel.a. Habit;b.flower;c. median sepal;d.petal;e. lateralsepal;
f.lip; g. column and lip, lateral view; h. column [a: de Vogel9292;b—h: Leiden cult, (de Vogel)
913697].
E.F.deVogel: Chelonistele laetitia-reginae, spec. Nov. 25
gins rolled backwards; nerves 5, midribhardly prominent. Lateralsepals slightly
asymmetric, elliptic, c. 15by 5 mm;top acute; marginsrolled backwards; nerves 5,
midribapronounced roundedkeel. Petalsrolledbackwards, linear, c. 13.5by 1mm;
topacute;nerve 1,midribnot prominent. Lip 3-lobed, twistedsideways, c. 15.5mm
long. Hypochilium rathernarrowly attached, slightly concave at thebase, in front
convex,c.7 by 4mm;laterallobesnarrowly triangularwith acute top,c. 3.5 by 1mm,
widthover thespread lobesc. 11 mm; keels2, starting beyond theconcave baseof
thelip c.2mmfromtheback, highest intheback, tothefrontlowering androunded,
continuing on theepichilium. Epichilium twistedsideways, curved downwards,ab-
ruptly dividedintoanarrow clawand anendlobewhichis widerthanlong, c. 10.5
by 13 mm; clawrectangular with aboutparallel sides, c. 5 by 3 mm,the twokeels
lowand rounded, continuing over about two-thirdofits length; endlobebutterfly-
shaped, slightly asymmetric, c.6by 13 mm,with shallowly emarginate top andab-
ruptly acutetip, thelaterallobesirregularly rectangular, slightly widening tothetop
whichistruncate torounded,withsomewhatirregular margin. Columnshort, widest
atthe topover theteeth, c. 6by4.5 mm;hoodrathernarrow, its topmargin with 4
big teethofwhichthelateralonesare narrowly triangularand c. 1.5by 0.5mmwith
entire margin, themediantwo triangular, c. 1.5 by 1mm withirregular margin, top
minutely apiculate. Antheraboutsemiorbicularin outline, c. 1.7by 2 mm;topbroad-
lyacute, tiprecurved.Polliniac. 1.5 by 0.8mm.Stigma semiorbicular, c. 1 by 2mm;
rostellumsemi-elliptic, c. 1 by 2 mm, topbroadly rounded, tip abruptly acuminate.
Fruitnot seen.
Collector'snotes— Young leaves andbractsbronzecoloured, leaveslatermid-
greenabove, lighter so below. Sepals and petals cream-colouredto pale ochrish
cream, sepalsonthemidribsometimestinged salmon.Lip creamcoloured, between
thekeels with abright yellow to orange-yellow longitudinal band, grading to dark
orangeto thebase. Columncream coloured, hooddarkbrownby many smalldark
brownspots, sometimesatthebase withatransverse orangeband.Antherpink light
reddish,polliniayellow. Scentsweet.
Etymology —Named tocommemorate the openingoftheVan Steenis Building
by Her Majesty Queen Beatrixon June 11, 1996.The epithet laetitia-reginae means
'thejoyoftheQueen', referring totheelegantpostureoftheflowerparts.
Distribution—Borneo: Sarawak(Bahagian Kapit). Knownfrom two specimens:
thetypeconsistingofinflorescencespreserved in spirit, andaherbariumspecimen,
deVogel 9292(SAR, L), fromthe samelocality.
Ecology — Epiphytes in elfinforest25 m high ona narrow sandstoneridge, at
1-2m high on trunksofsmall tomedium-sizetrees,tree trunks coveredwith moss.