Recircumscription of the Nepenthes alata group ( Caryophyllales : Nepenthaceae ) , in the Philippines , with four new species

An overview of Nepenthes in the Philippines is presented. Four new species, Nepenthes extincta sp. nov., N. kitanglad sp. nov., N. kurata sp. nov. and N. leyte sp. nov. are described and illustrated from the Philippines and placed in the Nepenthes alata group. An updated circumscription and key to the species of the group is provided. Delimitation and comparison with the Regiae group is given. All four of the newly described species are assessed as threatened using the International Union for the Conservation of Nature 2012 standard, and one, N. extincta sp. nov. is considered likely to be already extinct due to open-cast mining. Logging and conversion of forest habitat are thought to be the main threats to the other three species.


Introduction
This paper forms part of studies towards a World Monograph of Nepenthes L. (Linnaeus 1753) (Nepenthaceae), building on a Skeletal Revision of Nepenthes (Jebb & Cheek 1997) and the Flora Malesiana account (Cheek & Jebb 2001).
Nepenthes is the sole genus in its family.The species mainly occur in Malesia, but with ca. 12 outlying species in Madagascar, Seychelles, Sri Lanka, NE India, Indochina, Solomon Islands, New Caledonia and Australia.Cheek & Jebb (2001) recorded 87 species of Nepenthes, but since 1 st Jan. 2001, 50 new specifi c names have been published in the genus (International Plant Names Index continuously updated) and others have been resurrected from synonymy.The total number of species now accepted in the genus is estimated as140 and is set to rise further.
Within the Philippines 12 species were recognised in Cheek & Jebb (2001).Since 1 st Jan. 2001, 16 new names have been published at species-level for the country (International Plant Names Index continuously updated).These derive mainly from exploration of previously unexplored areas by Nepenthes enthusiasts (e.g.Heinrich et al. 2009;Cheek 2011) and are also due to the discovery of previously overlooked specimens in herbaria around the world (e.g.Cheek & Jebb 2013a, b, c, d).Some of the latter, e.g.Nepenthes alzapan Jebb & Cheek (Cheek & Jebb 2013b) are considered possibly already extinct, since habitat destruction in the Philippines over the last 100 years has been so extensive.The Philippines is thought to have remained two-thirds forested as recently as 1925 according to Sohmer & Davis (2007).Myers et al. (2000) estimated that remaining primary vegetation in the Philippines 75 years later amounted to only 3%.Lowland primary forest (occurring below 500 m) has now all but gone from the Philippines (Sohmer & Davis 2007).Sohmer & Davis (2007) estimate species extinction levels due to habitat destruction as between 9 and 28% in one representative, mainly forest genus, Psychotria L. (Linnaeus 1759) (Rubiaceae) which they revised taxonomically for the Philippines.Since habitat destruction continues in the Philippines, it is a race against time to discover, publish, assess and draw attention to the conservation needs of species before they become extinct, if they have not already been lost.
Of the species of Nepenthes known for the Philippines, about half occur in scrub or stunted habitats on ultramafi c substrates (both lowland and submontane) and appear to be restricted to this substrate, while the remainder occur mainly in submontane forest (500-2000 m) on non-ultramafi c, mainly volcanic substrates.Species diversity is highest on Mindanao Island, the southernmost and second-largest island, followed by Palawan Island.
All known Philippine Nepenthes species are endemic, apart from N. mirabilis Lour.(Druce) (Druce 1916;basionym: Loureiro 1790) which is known from Tawi Tawi Island close to Borneo, and from the northern coast of Mindanao and its associated islands.
Phytogeographically, the Nepenthes of Palawan have closer affi nities with Borneo than with the rest of the Philippines (Cheek & Jebb 1999).
Most of the endemic species can be assigned to one of three main groups: (1) The Nepenthes villosa Hook.f.(Hooker 1851) group, with petiolate leaves, well-developed lid columns, and peristomes with blade-like teeth, and lids which lack a basal appendage.These are restricted to higher altitude ultramafi c habitats and are most diverse in Palawan, but extend to NE Borneo (Cheek & Jebb 1999: 894).
(2) The Insignes or N. ventricosa Blanco (Blanco 1837) group which is most diverse in the Philippines (but absent from Palawan), extends to New Guinea and to Borneo and is characterised in Cheek & Jebb (2013b).In the Philippines they occur in both ultramafi c and non-ultramafi c, mainly submontane forest habitats.Its species lack a petiole, have broadly subcylindrical pitchers with a broad peristome which is conspicuously toothed on its inner surface, lids which lack appendages, and which have transversely elliptic nectar glands except along the midline band.
(3) The Nepenthes alata Blanco (Blanco 1837) group, characterised in Cheek & Jebb (2013d), is endemic to and extends throughout the Philippines except Palawan, is most diverse in Mindanao, and occurs in the same range of habitats as the Insignes.Its species have winged petioles, lids with basal ridges, usually producing appendages and upper pitchers usually broadest at the base.
Outside of these three groups, three other species occur, namely N. philippinensis Macfarl.(Macfarlane 1908), N. abalata Jebb & Cheek (Cheek & Jebb 2013a: 153) and N. micramphora V.B.Heinrich, S.McPherson, Gronem.& V.B.Amoroso (Heinrich et al. 2009).N. philippinensis is endemic to Palawan, and part of the N. hirsuta Hook.f.(Hooker 1873) group otherwise restricted to Borneo (Cheek & Jebb 1999: 890-891).The unusual N. abalata occurs only in the small low-lying, drier islands between Palawan and Panay Islands.It appears to be restricted to grassland and is similar and possibly related to the grassland species of Indo-China.Finally, N. micramphora of the extreme SE of Mindanao fi ts none of these groups and has an isolated position.
Many Philippine species of Nepenthes are only known from a single, sometimes sterile, specimen.However, usually there is little doubt that they are distinct taxa, since most characters of use in delimiting species in the genus are found in the pitchers and not in the fl owers or fruit.In Nepenthes the large number of taxonomic characters in the pitcher morphology and micro-morphology, especially in the upper and intermediate pitchers, parallels the importance of characters present in the fl owers and infl orescences of many other plant groups.In many other plant groups evolution of character diversity in fl oral characters appears to be correlated with assisting pollination, often by a single or narrow range of insect species.In Nepenthes, cross-pollination appears from initial studies to be performed by a broad range of generalist fl ies and wasps (Lian 1995;Adam 1998).Perhaps for this reason there is comparatively little specieslevel differentiation fl orally in the family.In contrast, evidence has been steadily accumulating in recent years that the pitchers of different Nepenthes species are specialised at gathering nutrients from one of a variety of animal sources.They are not always pitfall trappers of any prey item that happens to fall in, as had previously been assumed.Nepenthes species studied by Jebb (1991) in New Guinea predominantly trapped ants, but also a spectrum of other insects, while Nepenthes albomarginata T.Lobb ex Lindley (Lindley 1849) traps almost exclusively a species of termite (Clarke 1997).Nepenthes hemsleyana Macfarl.(Macfarlane 1908), the pitchers of which, providing day roosts for a species of bat, benefi t from the resulting faecal deposits produced (Grafe et al. 2011), while a group of Nepenthes species in montane Borneo are adapted to attract, detain and collect the faeces of a species of tree shrew and a rat (Greenwood et al. 2011).In each of these cases modifi cation in the morphology and micro-morphology of the pitchers appears to have been critical to collect nutrients from the target animals.
No doubt in future, morphological and micromorphological character states seen in the pitchers of other Nepenthes species or species groups, will also be shown to be important to targeting hitherto unsuspected specialised animal nutrient sources.
In the last three cases, the morphological modifi cations of the pitcher each appear to target only one or two species of animal.However, it is possible that future studies will show that some or most species of Nepenthes trap a wider range of insect species available in their environment.Since the range of e.g.arthropod species can be expected to vary from one mountain (or other geographic location) to another, it is possible that speciation in Nepenthes might be driven by modifi cations of the pitcher caused by selection for effi ciency in trapping, or otherwise targeting, the spectra of animal species present at each.This might explain the common pattern seen in several Nepenthes groups to have different species, as recognised by pitcher morphology and micromorphology, on different mountains or islands.
An alternative hypothesis to explain this speciation pattern invokes genetic drift (Stace 1991).In this hypothesis, the progeny of the few founding individuals at a new location might accumulate morphological changes over time independent of any selection pressures, for example as postulated for Podostemaceae Rich.ex Kunth (Kunth 1816) species at the same waterfall by van Steenis (1981), exemplifying his theory of autonomous evolution.This scenario assumes that animal targeting is not strongly selected for in Nepenthes.This might be the case if the threshold for the need for nutrients derived from animals in Nepenthes is very low, or if there is no threshold at all, for example if Nepenthes can survive without capturing animal nutrients through their pitchers.

Materials and Methods
The data in this study, one of a series, derives from herbarium specimens including their corresponding fi eld notes, and if available, photographs.The location of the herbarium at which the specimens are located is indicated by the citation of the international code registered in Index Herbariorum (Thiers continuously updated).
The shape and dimensions of the upper and intermediate pitchers, including those of the body, mouth and lid of the pitcher, and of the fringed wings if present, are useful characters.The shape and features of the lower surface of the pitcher lid, and the shape of the pitcher mouth and its peristome are the largest source of such characters, as are the nectar glands on the lower surface of the lid (Cheek & Jebb 2001).The nectar gland size, shape, orientation, position, density and the absence or, if present, the extent of a nectar gland perimeter wall, can be especially useful in delimiting species.In some species nectar glands are dimorphic, and in a very few, trimorphic.Indumentum is also frequently an important source of species characters.Here the classifi cation used in Cheek & Jebb (2001: 7-8) is maintained.
Since the mouth and the lid surface are often obscured or not presented in mounted herbarium specimens of Nepenthes, it is frequently necessary, after prior permission from the herbarium manager of the specimens concerned, to soak the mouth area and lid, and sometimes entire pitchers, in warm soapy water so that they can be repositioned for study of the mouth and lower surface of the lid.By this means it is possible to view the three-dimensional shape of the pitcher, if this is not already known from photographs or observation of live material.
Measurements are made of stem, leaf and pitcher dimensions using a graduated ruler.The full range of measurements is given in the description, with extreme dimensions, disconnected with the normal range, indicated in brackets, e.g."leaf-blade 12.5-22(-28) cm long", indicating that a single leaf-blade was measured as 28 cm long, all others being in the 12.5-22 cm long range.Observations and measurements of hair dimensions and of peristome and lower lid details are made with a Leica Wild M8 binocular microscope fi tted with an eyepiece graticule graduated in units of 0.025 mm at X40 magnifi cation.The drawings were prepared with the aid of a camera lucida fi tted to the microscope.
The four species described as new in this paper, N. extincta sp.nov., N. kitanglad sp.nov., N. kurata sp.nov.and N. leyte sp.nov.came to light when examining loans of previously unstudied specimens from E, BISH and BRIT, which were compared with material from B, BM, BO, F, GH, K, KEP, L, NDC, NY, PH, S, W, WAG, U, UC, US, on which earlier studies have been published (Jebb & Cheek 1997;Cheek & Jebb 1999, 2001;Cheek 2011;Cheek & Jebb 2013a, b, c, d).The material referred to matched no other species description, as represented by the both the specimens from the herbaria cited, and by protologues and other literature regarding the species for which material is only available in the Philippines and not available for loan.The material best fi tted the characters of Nepenthes group (3) described above, that is the Nepenthes alata group.However, unusual features for this group were present, which are considered in the discussion at the end of this paper.A key to the species of the group is provided below.
The rapid increase in the number of new species from Mindanao in recent years is likely to continue as specimens become available from new areas.Many of the species of the N. alata group on this island seem narrowly geographically localised, although others, such as N. gracilifl ora are widespread.
Since the terrain of Mt Malindang is reported as being rugged, with much forest surviving, there is every reason to hope that the species survives there, unlike Nepenthes robcantleyi Cheek (Cheek 2011) also from Mindanao, which is already suspected to be extinct in the wild due to the almost total clearance of forest habitat at the single known wild location due to logging (Cheek 2011).

Remarks
The fi rst Nepenthes taxa described from Mindanao, both of the N. alata group, (Cheek & Jebb 2013d) 1F-H), only one of the four has an appendage, and that is only moderately developed as a convex emergence from the basal ridge (Fig. 1H).However a recent collection (Gaerlan et al. in PPI 10977) with upper pitchers, does show a developed appendage (Fig. 1E), suggesting the epithet ecristata "lacking a crest" is inappropriate.In any case, the Code demands priority only at one rank, so there is no requirement to adopt the varietal epithet at specifi c level, for which reason Macfarlane's taxon is renamed as N. kurata sp.nov.
The upper pitchers also differ from the intermediate pitchers in the greater density of the nectar glands on the lower surface of the lid.However the shape, distribution and size of the nectar glands remain similar.
This is the only known species of Nepenthes from Mt Malindang at this time, and it is therefore the most westerly known species of the genus in Mindanao.Nepenthes kurata sp.nov. is still incompletely known, full details on its ecology, altitudinal range, population density, infl orescences and infructescences, and ethnobotany remain to be discovered.
The type specimens were collected by Major E.A. Mearns and W.J. Hutchinson in 1906 on the fi rst recorded ascent of Mt Malindang, a volcanic mountain in the NW of Mindanao.Both sheets are annotated in the hand of Macfarlane as "N.alata var.ecristata Macfarlane", and either could be selected as lectotype of that name.The K sheet is accordingly selected.diagonally as a narrow wing, in short stems 7 mm long, in climbing stems 18 mm long, and continuing as a ridge to the node below.Lower pitchers narrowly ovoid-cylindric, 12.5 cm tall, 5 cm broad, widest in the basal half, narrowing steadily to ca. 3 cm wide below the peristome; outer surface 10-25% covered in pale brown hairs of two types, (1) bushy brown hairs 0.1-0.25 mm long and wide, with 4-8 arms ascending from a short central axis, 7-12 per mm 2 , (2) long brown straight erect hairs 1.5-1.75(-2.5) mm long, with 2-4 short branches ascending from along the length of the main axis, sparse; fringed wings, 2-4 mm wide, running 3-4 cm from peristome towards base of pitcher, then diminished to slender ridges, wings extended over the peristome by two foliose fl aps 3-4 × 3-4 mm, fringed elements 4-5 mm long, 2.5 mm apart (1.5 mm apart on foliose fl aps); mouth ovate-lanceolate, highly oblique, concave, ca.4.1 × 2.8 cm; column developed, tapering towards lid ca. 9 mm long, 2.5 mm wide at midpoint; peristome subcylindric, 1 mm wide at front of pitcher to 3 mm wide at sides, ridges ca.2.5 per mm, ridges 0.1 mm high, inner edge lacking conspicuous teeth or holes, outer edge not lobed.Lid narrowly ovate to rhombic 3.5 × 2.3 cm, apex rounded, base rounded to truncate, lower surface lacking a basal appendage, but with a low basal ridge 10 mm long, 0.5-1 mm high, extending from the junction with the peristome; nectar glands small and sparse, 6-8 on each side of the midline which mainly lacks glands, absent from basal ridge, nectar glands monomorphic, slightly perithecoid, orbicular or slightly elliptic, 0.25(-0.35)mm long, mixed with denser sessile depressed-globose, red-black glands, 0.05-0.1 mm diam., 8 per mm 2 ; marginal 2-3 mm of lower surface with minute stellate hairs densest near margin; upper surface with same indumentum as outer pitcher surface, but long hairs rarely seen.Spur not seen.Upper pitchers (tendril coiled) ovoid-cylindric, green, slightly maroon above, 21.5 × 6.5 cm, widest in the ovoid basal third, narrowing to ca. 5 cm wide in the cylindrical upper part; outer surface with same indumentum as lower pitcher; fringed wings reduced to ridges apart from two foliose fl aps immediately below peristome, point of attachment 3-4 mm long, angular-elliptic, 9 × 6 mm, bearing fringes 2-7 mm long; mouth ovate-lanceolate 7 × 4 cm, oblique, concave, the frontal part straight; column ca.1.5 × 0.8 cm; peristome rounded-fl attened, 1.75-5.5 mm wide, widest at sides, ca.1.75 ridges per mm, ridges 0.1 mm high, inner edge lacking conspicuous teeth or holes, outer edge not lobed.Lid ovate-triangular, 5 × 3.8-4.2cm, apex rounded, base truncate; lower surface with a weakly developed, convex basal appendage 1.5 mm high, arising from a low basal ridge 7 mm long; nectar glands ca.16 on each side of the midline, sparsely scattered, more or less absent from midline, but present at appendage, nectar glands orbicular or slightly elliptic, slightly or strongly perithecoid, 0.25-0.5 × 0.25-0.45(-0.75)mm; sessile glands 0.05-0.1 mm diam., 8-20 per mm 2 ; upper surface of lid with indumentum as outer surface of pitcher.Spur inserted 2 mm below junction of lid and pitcher, pointing downwards, terete, 17 × 0.9-1 mm, dilating to the 1.8 mm wide rhombic-acute apex, indumentum moderately dense of long patent simple hairs as on the pitcher outer surface.Male and female infl orescences unknown.

Conservation
Here N. kitanglad sp.nov. is assessed as Critically Endangered since it is known from only a single location, Mt Kitanglad, on an island which has seen extensive forest clearance for logging and agricultural expansion in recent years (McPherson 2009: 759).For these reasons one species, N. robcantleyi Cheek is already suspected to be extinct in the wild (Cheek 2011).Nepenthes kitanglad sp.nov. is not a spectacular or especially bizarre species so is unlikely to come under pressure of collection for the horticultural trade which has brought several species of the genus close to extinction.(2009: 755-759; fi gs 417 & 418) depicts from volcanic Mt Kitanglad in N-Central Mindanao a plant under the name of N. saranganiensis Sh.Kurata (Kurata 2003: 41).Yet, the Kitanglad plants he depicts differ from N. saranganiensis as depicted in its protologue in habit, habitat and in morphology.In 2013 sheets of Gaerlan et al. in PPI 3274 (BISH,BRIT) became available from Kitanglad.These matched McPherson's (2009) depiction, enabling a detailed comparison to be made with N. saranganiensis.The conclusion is that the Kitanglad material represents a different species from N. saranganiensis and is here described as N. kitanglad sp.nov.Differences between the two taxa are given in Table 2. N. kitanglad sp.nov. is unusual in the N. alata species group (Cheek & Jebb 2013d) in the strongly concave mouth of the upper pitchers, in which the base of the lid is held over the mouth.It is also unusual in that the rear of the peristome narrows to a neck, forming a moderately well-defi ned column for the lid.Within the N. alata group, these two features are otherwise currently known only in N. hamiguitanensis Gronem., Wistuba, V.B.Heinrich, S.McPherson, Mey & V.B.Amoroso (Gronemeyer et al. 2010), but that species is restricted to ultramafi c Mt Hamiguitan in SE Mindanao and differs greatly in the shape of the upper pitchers which are stout, widest at the midpoint, with a funneliform lower half narrowing to a more slender, cylindrical upper half.It is possible that N. hamiguitanensis, N. kitanglad sp.nov.and N. saranganiensis are related since all have angled stems (or in the case of the last species, winged), a feature otherwise unknown in the otherwise terete-stemmed N. alata group.Nepenthes kitanglad sp.nov. is unique in the N. alata group in its lid posture, as seen from photographs and herbarium specimens.The lid is held at ca. 45° below the horizontal, largely concealing the mouth.In other species it is usually elevated above the horizontal, sometimes by ca.45° (N.saranganiensis) or as much as 90° or more (N.gracilifl ora Elmer).So far, N. kitanglad sp.nov. is the only species of Nepenthes recorded from Mt Kitanglad.

Distribution & habitat
Philippines, Mindanao, Surigao del Sur.Open scrub habitats on ultramafi c substrate with N. merrilliana Macfarl.(Macfarlane 1911) and N. gracilifl ora Elmer (Elmer 1912).Elevation: ca.400 m.  (Almeda 2012).It is much to be hoped that this species is refound, and not proved to be extinct, and if found, that it can be protected and monitored.

Remarks
Nepenthes extincta sp.nov. is most likely to be confused with N. mindanaoensis and they may share a common origin.Both species occur on open ultramafi c substrates in NE Mindanao, both have robust, ovoid-cylindric pitchers arising from thickly leathery blades in which the longitudinal nerves arise from the base of the blade.In both species the petiole has involute wings, so appear cylindric, and the blade is not decurrent to the petiole -unusual features in the N. alata group.The two can be distinguished using the characters in Table 3.The two species are not sympatric so far as is known.
Fumihiro Konta, collector of the only known material of this species, has not been traced by us.An internet search shows that he has published on the plants of S China and Thailand, as well as Japan, covering specialisms such as Asclepiadaceae, Ferns and Vegetation mapping."A list of the Ferns and Flowering Plants of Mt Fuji, 1984" is his most referenced work.Since "Environmental Impact Studies" are listed among his interests, it may have been in that context that he collected the type specimen recorded here.

Conservation
Nepenthes leyte sp.nov. is known currently from a single individual in an unprotected area, in a country, including specifi cally the island of Leyte, where most of the original forest habitat has been cleared for timber and agricultural land and where forest degradation and clearance are ongoing (Myers et al. 2000;GoogleEarth viewed 2 Oct. 2013).Accordingly, it is here assessed as Critically Endangered under Criterion D of IUCN (2012).It is to be hoped that further exploration will reveal additional localities for the species, and that protection can be arranged before it becomes extinct.Currently no protected areas are believed to be present on Leyte apart from the 2193 ha Lake Danao National or Natural Park which is about 14 km to the W of the type location.However this seems to be mainly a recreational area, and within the reserve, illegal settlement, slash and burn agriculture and illegal logging are reported to be problems (http://en.wikipedia.org/wiki/Lake_Danao_(Leyte)#Threats,viewed 12 Oct. 2013).Viewing the area immediately around Lake Danao on GoogleEarth (2007 imagery, viewed 12 Oct 2013) confi rms that large areas have been and were in 2007 in the process of being cleared and inhabited, and that these activities extend towards the E and the only known location for N. leyte sp.nov.Some original forest still survives along the central high ridge of Leyte, where terrain appears rugged, including the location indicated as the type location of the species, however the resolution of the imagery here is not suffi ciently high to gauge how intact the habitat is.The eastern side of Leyte has higher rainfall and the forest has extensively been replaced by intensive industrial oil palm plantations which extended in 2003 to within 4 km of the type location (GoogleEarth imagery dating from 2003, viewed 2 Oct. 2013).Collection of Nepenthes leyte sp.nov.from the wild to supply the horticultural trade is considered a low risk for this species since its pitchers are not as spectacular or as bizarre as those of other members of the genus in the Philippines.

Discussion
In an earlier paper, the Nepenthes alata group of species, confi ned to the Philippines, was characterised and a key was provided to the then recognised species (Cheek & Jebb 2013d).In that paper the species of the N. alata group were characterised as possessing: (1) a basal appendage on the lower surface of the pitcher lid, (2) a terete stem, (3) a distinct, but winged petiole, the petiole wings wide, decurrent from the blade, (4) the peristome fi nely ridged, the outer edge not or only slightly lobed, (5) the inner surface lacking conspicuous teeth, (6) the mouth ovate, oblique, without a well-developed column (Cheek & Jebb 2013d).
The four new species described here have characters that necessitate modifi cation of the Nepenthes alata group as circumscribed in Cheek & Jebb (2013d).All but N. leyte sp.nov. of the new species have stems that can be 4-angled in section rather than terete.In N. extincta sp.nov.and in N. leyte sp.nov., the petiole wings are incurved, the two edges overlapping, giving the petiole a cylindrical appearance.Both N. extincta sp.nov.and N. kitanglad sp.nov.have broad, partly fl attened peristomes (rather than narrowly cylindric) and pitcher mouths which are concave (rather than straight).In the case of N. kitanglad sp.nov., a moderately well-developed column is formed (rather than none, or a weakly developed column).Several of these characters are more usual in the Regiae group of species of Danser (1928), which are considered by us to be closely related to the N. alata group.The two species groups share (1) petiolate leaves and, (2) on the basal part of the lower surface of the lid, appendages emerging from a keel-like ridge or crest, and (3) infl orescences with 2-fl owered partial-peduncles.The two species groups can be both defi ned and separated from each other using the key below.It is possible that future discoveries will provide evidence that the two groups are a continuum, and should be united.
-Upper pitchers infundibuliform or infundibuliform-cylindrical, always widest at the peristome; petioles not or weakly winged, U-shaped in section, the wing width if present, shorter than the width of the central, non-winged part of the petiole; stem and leaf indumentum of persistent, red-brown bristle-like hairs.(Danser 1928)

Fig. 1 .
Fig. 1.Nepenthes kurata sp.nov. A. Habit, climbing stem with upper pitcher.B. Indumentum of midrib, lower surface of leaf-blade.C. Indumentum of tendril.D. Indumentum of outer pitcher surface.E. Lid, lower surface, showing nectar gland distribution on right (upper pitcher).F-G.Profi les of basal lid ridges, without appendage (F), with appendage weakly developed (G), and moderately developed (H).I Spur of intermediate pitcher.J. Longitudinally elliptic nectar glands of lid midline.K. Orbicular nectar glands of lid, outside the midline.L. Peristome from above, short teeth and holes discernible.M. Peristome viewed from inside pitcher.N. Peristome transverse section, outer surface to right.A-E, J & K from Gaerlan et al.PPI 10911; F-I, L-N from Mearns & Hutchinson 4632.Scale bars: single = 1 mm; graduated single = 2 mm; double = 1 cm; graduated double = 5 cm.All drawn by Andrew Brown.

Fig. 3 .
Fig. 3. Nepenthes extincta sp.nov. A. Habit, showing intermediate pitcher.B. Indumentum, lower surface of blade (midrib on left).C. Branched bristle hairs (detail from lower surface of blade).D. Stellate hairs and sessile glands (detail from lower surface of blade).E. Branched erect hairs (detail from lower surface of blade).F. Stellate hairs, with appressed arms, leaf-blade lower surface, near midrib.G. Upper part of intermediate pitcher, lid posture as in life.H. Lower surface of upper pitcher lid.I. Basal lid appendage and spur.J. Basal lid appendage and ridge, side view.K-M.Details of nectar glands, lower lid surface.N. Indumentum, outer surface of pitcher.O. Peristome, view from inside pitcher showing minute teeth and holes at edge.P. Peristome, view from above.Q. Transverse section of peristome (outer surface on right).A-F & H-Q from Konta 12365, G from sketch by M. Cheek.Scale bars: double, graduated = 5 cm; single = 1 mm; single graduated = 2 or 3 mm as indicated.All drawn by Andrew Brown.

Fig. 4 .
Fig. 4. Nepenthes leyte sp.nov. A. Habit, climbing stem with upper pitchers.B. Stem section showing axillary hair patch and supra-axillary bud.C. Lower surface of leaf-blade, with sessile glands.D. Midrib of leaf-blade, lower surface, stellate to simple hairs.E. Midrib of leaf-blade, upper surface with stellate hairs.F. Upper lid of pitcher, upper surface.G. Indumentum of upper surface of lid, over nerve.H.As G but distant from nerve.I. Spur of upper pitcher and junction of lid with peristome (inverted).J. Lid of upper pitcher, lower surface.K. Detail of J showing large nectar glands.L. Detail of J showing midline ridge with appendage and type (1) nectar glands.M. Indumentum of outer pitcher surface.N. Peristome of upper pitcher viewed from above.O. Peristome viewed from inside pitcher.P. Peristome dissected to expose the inner edge, with teeth.Q. Peristome, transverse section (outer surface on right).All drawn from Argent et al. 99214 by Andrew Brown.
(Cheek & Jebb 2013d.ecristataMacfarl.(Macfarlane1908),based on Mearns & Hutchinson 4632 from Mt Malindang, and N. copelandii Macfarl.(Macfarlane1908) from Mt Apo.The fi rst of these we here elevate to species level as N. kurata Jebb & Cheek sp.nov.Previously we had considered this taxon to be synonymous with N. mindanaoensis Sh.Kurata(Kurata 2001)(Cheek & Jebb 2013d).The two taxa do have similarities in the overall shape of the upper pitchers, the weakly to moderately developed basal lid appendage and the sparse nectar glands of the lower lid surface.However they can be distinguished using the characters in Table1.The number and extent of these features merit elevation from varietal to specifi c-level recognition in our opinion.Although the type specimen has rosette stems and intermediate pitchers only, a second specimen, with climbing stems and upper pitchers, Gaerlan et al. in PPI 10911 came to light recently.It is from the type locality and matches the type in essential details.Nepenthes kurata sp.nov.has the spot character within the Nepenthes alata group of a small, more or less orbicular lid, only about half the length of the pitcher mouth.
Macfarlane (1908)characterised his N. alata var.ecristata by the lid appendage being either reduced or absent; the nectar glands being few, medium to large in size, and irregularly dispersed.Of the single specimen cited (Mearns & Hutchinson 4632), only two sheets (PH and K) have been found, both annotated in Macfarlane's hand, each with two intermediate pitchers.Although all four pitchers share a basal ridge (Fig.
Jebb & Cheek sp.nov.urn:lsid:ipni.org:names:77134487-1Fig. 2 Diagnosis Differs from N. saranganiensis Sh.Kurata in having angled, (not winged) stems, lower and upper pitchers strongly dimorphic, (not subdimorphic); in being a climbing epiphyte of forest (not a terrestrial shrub of open areas) and in having a strongly concave pitcher mouth with a long neck (not with the pitcher mouth fl at or only slightly concave, lacking a neck).EtymologyNamed, as a noun in apposition, for Mt Kitanglad, the type and only known locality of the species.TypePHILIPPINES.Mindanao, Bukidnon Province, Intavas, Impasug-ong, Mt Kitanglad, 18 Jul.1991, Gaerlan, Sagcal & Fernando in PPI 3274 (holotype BISH!; isotype BRIT!).apart from margin but with indumentum as stem, densest on midrib but soon glabrescent; lower surface with sessile depressed-globose red-black glands ca.0.05 mm diam.; margin densely fringed with soft fi ne orange-brown patent simple or bifurcate hairs 1 mm long.Petiole evenly winged along its length, 4-5 × 0.4-0.9cm, wings patent; at base clasping the stem for ⅔ to ¾ of its circumference, decurrent Nepenthes kurata sp.nov.

Table 2 .
Diagnostic characters separating N. saranganiensis and N. kitanglad sp.nov.DiagnosisDiffers from N. mindanaoensis Sh.Kurata in the pitchers lacking fringed wings (versus with fringed wings), the lid base truncate (not cordate), the indumentum of the midrib of dense minute grey-white stellate hairs, (not of sparse black bristle-like hairs).Nepenthes extincta sp.nov. is named to signify that this species may already be extinct globally.Red Hills (= 400 m alt.), SE of Claver, near the northeastern coast of the Mindanao Island.Boundary of the Surigao del Sur and Surigao del Norte" 8 Aug. 1978, Fumihiro Konta 12365 (holotype BISH!).
(Pacudan 2013)cta sp.nov. is here assessed as Critically Endangered under Criterion D ofIUCN (2012)since only a single individual has ever been recorded (the type specimen collected in 1978).The locality data given corresponds with the large area of ultramafi c known as 'Red Mountain' SE of Claver in NE Mindanao.In fact, Red Mountain is a series of low red hills.The NE Mindanao, probably due to its large areas of ultramafi c substrate, supports several narrowly endemic and often spectacular Nepenthes species, several of which are known from single locations.For this reason, it has been intensively visited in recent decades by devotees of the genus.Despite this, no additional collections or observations of this taxon have come to light in the last 25 years and it is possible that it is restricted to the Red Mountain, and is now extinct, since this happens to be the largest nickel mining site in the world's second largest nickel producing country (Gallares 2013).The Foundation for the Philippine Environment(Pacudan 2013) recently reported on the environmental damage due to extensive and massive nickel mining "as far as your eyes can see.","Thescene of endless open pit mining at the red mountain made our heart bleed."(Pacudan2013).The biggest mining companies operating at the Red Mountain are Taganito Mining Corporation, Platinum Group Metals Corporation (PGMC), Taganito HPAL Nickel Corporation, Adnama Mining Resources Inc. (AMRI) and Zhen Shou Mining
Argent et al. 99214, here described as Nepenthes leyte sp.nov., while superfi cially similar to N. gracilifl ora, the only other species of the genus known on Leyte (Wenzel 680, GH!;Barbon et al. in PPI  8735, BRIT!; ibid.8561,BRIT!), cannot be confused with it.This is due to the stellate hairs present on the outer pitcher surface of Nepenthes leyte sp.nov.(versus absent in N. gracilifl ora), and the dimorphic nectar lid glands concentrated around the margin and appendage (not monomorphic, uniformly dense and distributed).It also has petioles that appear cylindrical since the wings are involute (not with patent wings).Apart from N. gracilifl ora itself, only one other member of the N. alata group is, so far, known from the Visayas: N. negros (Negros and Biliran islands).However, N. negros has densely hairy stems (versus glabrous), upper pitcher with fringed wings (not absent) and the inner peristome edge has conspicuous teeth and holes (versus conspicuous teeth absent).Nepenthes leyte sp.nov.can be distinguished from other species of the Nepenthes alata group using the key above.