New Species of Stylidium , and Notes on Stylidiaceae from Southwestern Australia

Three new species of Stylidium from southwestern Australia are described. Stylidium noriscandens is most closely related to S. scanclens, of which it may be regarded as a northern sandplain vicariant with sufficient morphological difference for specific recognition, just as S. veiticillatum is a montane vicariant of S. scandens. Stylidium expeditionis is a new species known only from the Tutanning Reserve near Pingelly; it is in the section Squamosae, and several species can be cited as bearing relationship to it. Stylidium ricae is the name given to a plant of granitic outcrops near Morawa and Mullewa; it was formerly designated S. macrocarpum var. planifolium, but is amply distinct although related to S. macrocarpitm and S. pycnostachyum. The three new species are illustrated photograJJhically, using photomacrographic detail. Additional notes on species of Stylidiaceae described in 1969 are given. In an earlier paper ( Carlquist, 1969 ), I predicted that additional species of Stylidium remained to be discovered in Australia. During my 1974 expedition, I found three Stylidiums which prove to be new species. In addition, observations made in 1974 with regard to the species described in 1969 are offered in the closing part of this paper. The three new species are described below without citations to figures interspersed into the text, because the reader can easily compare the photographs with the descriptions. Stylidium nonscandens Carlquist, spec. nov. Frcs. 1-12 Perennis glabra, 20-45 cm alta. Innovationes erectes , quadrangulares, roseo-bmnneae, folia dense rosulata-verticillata, verticillis ca. 6 ( 2-8) cm inter sese distantibus. Folia ecirrhosa, linearia vel trigono-linearia, glabra, apice acuta, 5-50, saepius 27 mm longa. Racemi terminales solitarii, 3-5 usque 9 cm longe pedunculati, bracteae lineari-subulatae acutissimae; pedicelli , 5-1.5 cm longi, prophyllis 2 bracteis sirnilibus minoribus instructi. Calycis !obi acuti, tubo aequilongi, ca. 3 mm longi. Corolla rosacea, tubus brevis, laciniae obovatae, ca. 7 mm longae, ca. 5 mm latae, corolla postice duplo profundius quam lateribus inter lacinias incisa. Appendices faucis 6, ante lacinias posteriores binatae minimae subulato-filiformes, ante anteriores singulae majores, late-oblongae apice acutae rotundatae vel truncatae. Labellum anguste triangulari-ovatum acuminatum, ca. 2 mm longum, glanduloso-ciliolatum, basi appendiculis filifonnibus glanduloso-pilosis labello aequilongis instructum. Columna breviter glanduloso-pubescens ; thecae antherarum 1 I acknowledge the help of Mr. Alex George, Mr. Kevin Richards, and Mr. Larry De Buhr during my field work in 1974. This study was aided by a grant from the National Science Foundation, GB 38901.


Stylidium nonscandens
Shrublike glabrous perennial 20-45 cm tall, branched from near the base, the innovations erect, with quadrangular reddish-brown stems. Leaves in dense verticillike rosettes, these spaced mostly about 6 ( 2--8) cm from each other along the stems. Leaves not hooked at tips, linear ( triangular in transection) glabrous, apices acute, 5-40 mm long, averaging about 27 mm. Racemes terminal and solitary, the inflorescence axis ("peduncle") 3-5 or up to 9 cm long, with linear-subulate acute bracts at bases of branches ("pedicels"), these pedicels 0.5-1.5 cm long, bearing pairs of prophylls similar to the bracts but sinaller. Calyx lobes acute, about the same length as the h1be (ovary), about 3 mm long. Corolla pale rose, tube short, the lobes obovate, about 7 mm long by 5 mm wide, the corolla limb twice as deeply incised dorsiventrally as laterally ( lobes united into lateral pairs). Throat appendages 6, the posterior 4 minute and tending to be united into pairs, the anterior 2 larger, broadly oblong, and with acute, roundish or b"uncate tips. Labellum narrowly ovate-triangular, acuminate, about 2 mm long, glandularciliate, provided with a p air of filiform glandular-pilose basal appendages about the same length as the labellum proper. Column covered with short glandular hairs; anther sacs acute, with numerous vesiculate hyaline trichomes clustered around the thecae. Seph1m of the ovary reduced to a crescent with a thick subglobose basal placenta bearing several large erect ovules. Capsule at mah1rity about 6 mm in diam. Styliclium nonscanclens has been named deliberately to compare it to S. scanclens R. Br., to which it is related. Juvenile shoots of S. scanclens can be quadrangular and bear linear leaves lacking hooks at their tips as in S. nonscanclens. However, stems of S. nonscanclens are always quadrangular ( like those of S. verticillatum F. Muell. ) , and leaves never bear hooks at their tips and never form any kind of tendrillike attachment to surrounding vegetation. Indeed, the shrublike plants of S. nonscanclens grow scattered among -2. Rosette of leaves terminating one of the stems, illustratin g linear nature of leaves, which lack recurved margins.--3. Corolla; face view to show shape of lobes.-4. Center of corolla; column has been arranged atop corolla limb to show details of glandular hairs; throat appendages visible at base of column. the low shrubbery of depauperate sand heath which consists ( except for mallees and Banksias) of growth as low as or lower than the S. rionscandens plants. The adult tendril-tipped leaves of S. scandens are markedly concave along the midrib above and have recurved margins, features not present in leaves of S. nonscandens.

Holotype
The calyx lobes of S. nonscanclens are markedly narrow and acute, and thus like those of S. verticillatum, whereas calyx lobes of S. scandens are broad, rounded, and obtuse. The corolla of S. nonscandens is the same size as that of S. scandens, but never deep rose in color ( as in some populations of S. scandens); the lobes are united for about half their length laterally, as in S. verticllatum. The throat appendages of S. nonscandens are much smaller than those of S. scanclens. The labellum of S. nonscandens is like that of S. scandens except that the basal appendages are not long; they are slightly shorter, in fact, than the main lobe of the labellum. The vesiculate hairs among the anthers (figured well by Erickson, 1958, for both S. scanclens and S. verticillatum) are particularly conspicuous in S. nonscandens ( Fig. 9 ). The capsules of S. nonscanclens differ from those of both S. scandens and S. verticillatum in that those two species have only a globose placenta, whereas a crescentlike septum is present in capsules of S. nonscanclens ( Fig. 12). In this respect, S. nonscanclens resembles S. galioicles C. A. Gardner, a sp ecies that has large seeds similar to those of S. nonscanclens. Styliclium nonscanclens is like S. scanclens and unlike S. verticillatum in that it lacks vesture except on portions of the flower ( glandularpubescent in all three species).
Styliclium nonscandens is thus a northern vicariant of S. scandens. Such characteristics as the acute calyx lobes and presence of a capsule septum show that it is not merely a juvenilistic variant of S. scandens. It is to be exp ected in various areas of the great sandplain around Jurien Bay from Greenhead to Gingin, and might have been discovered previously had this recently opened area been botanized during the brief flowering season of S. nonscanclens. Plants were particularly abundant along the road west from Coorow, forming conspicuous displays in the segment from 34 to 39 mi W of Coorow. I was alerted to the possible distinctness of S. nonscanclens by finding it in these localities so far north of the habitats of S. scandens. Stylidium scanclens is a species of the south coast of southwestern Australia, ranging from approximately Mt. Manypeaks along the Albany and Northcliffe coasts to Bun bury ( Erickson, 1958). That area is rich in the Restionaceae on which S. scandens so typically climbs. Styliclium verticillatum is also a southern species, endemic to scree slopes in the Stirling Range ( Carlquist, 1969). Styliclium verticiUatum can be regarded as a vicariant of the S. scanclens complex, just as may S. galioicles, which grows among white quartz boulders in the Mt. Barren range south of Ravensthorpe and Jerramungup. Carlquist, spec. nov. Fies. 13-21
Holotype.-In white sand with Styliclium breviscapum R. Br. , S. squamellosum DC., Levenhookia stipitata ( Ben th.) F. Muell., Dryanclra, Leucopogon, Xanthorrhoea; scrubby area at northwestern corner of Tutanning Reserve east of Pingelly, Western Australia. October 9, 1974, Carlquist 5960 ( RSA ) . Stylidium expeclitionis is a member of the section Squamosae of Mildbraed ( 1908). Although not clearly more nearly related to one particular species of this section than others, it may be compared to S. caricifolium Lindi. However, S. caricifolium, including its three subspecies ( Carlquist, 1969) forms caespitose, much-branched tufted plants, as do most species of the section Squamosae. Styliclium expeclitionis is unique in the section, to the best of my knowledge, in invariably producing a single shoot per plant each year without branching. Old plants therefore have elongate stems from which adventitious roots grow down to the soil. Adventitious roots are a characteristic feature of Styliclium species, probably because vascular bundles lack secondary growth, and formation of adventitious roots probably occurs for much the same reasons as in monocotyledons, which also lack secondary growth in vascular bundles. One can assume that as the unbranched stem of S. expeclitionis elongates over a number of years, eventually the height of the leaf rosette attains a position untenably high for growth of adventitious roots from the rosette to the soil surface, and either for lack of water supply or support by the roots, or both, the plant eventually declines. Leaves of S. expeclitionis are much shorter and narrower than those of S. caricifolium, are obtuse, and are bisulcate on both surfaces. This last feature is unique within the section Squamosae. The scale-leaves, like the leaves, are short compared to those of other species of Squamosae.
Calyx lobes of S. expeclitionis are narrower than those of S. caricifolium.

Stylidium ricae
Perennial glabrous in vegetative portions, the stems densely grouped in a caespitose fashion, never giving rise to proliferations as offshoots with elongate stems as in S. macrocarpum, very thick and short ( as long as wide), tightly rooted in rock crevices. Leaves basal, narrowly oblanceolate, 10 ( 7-10) cm long, up to 3 mm wide, not succulent but flat, petiolate, the upper surface of the lamina concave and with globose-papillate epidermal cells; leaf tip acute. Scape about 22 ( 15-30) cm long, tinged rose in lowermost portions but otherwise green, simple ( the branches one-flowered pedicellike) above, with 0-3 branches below bearing 2-3 flowers at most in a cymose fashion. Scape monoaxial, never corymbose or subdivaricately branched. Bracts narrowly linear. Scape hirsute in upper portions. Flowers sessile ( the upper on pedicellike bracteole-bearing one-flowered branches such as have been termed pedicels usually in Stylidiaceae). Calyx tube densely glandular-pubescent, terete, 7-15 mm long at anthesis. Calyx lobes glabrous, narrowly acute, 1.5 mm long, rose above, rose and glandular below. Corolla tube the same length as calyx lobes or shorter, lobes of the same size, paired laterally, roundish-oblong, 2 mm long, 1.5 mm wide. Throat bare. Labellum minute, obtuse, provided with triangular appendages at the base. Column with clavate vesicular hairs at tip, anthers dark brown. Capsule linear, 1.5-2 cm long. Holotype.-Although Erickson and Willis ( 1956) differentiated between holotypes and isotypes for the entities they named, with the holotypes located at MEL, by clerical error they did not do so for S. macrocarpum var. planifolium. Their citation reads, "TYPE from stony slopes near Billerango Hills, SW of Morawa, Western Australia ( ISOTYPES in MEL, K, and PERTH-Rica Erickson, 10 Sept. 1953) ." In accord with the intent of these authors, I designate the holotype of S. macrocarpum var. planifolium, and therefore for S. ricae, to be the MEL specimen. From a single dried specimen, one might easily consider S. ricae merely a variant of S. rnacrocarpum. However, observations on living material and a series of dried specimens show it to be an amply distinct species with nearly as many resemblances to S. pycnostachyum Lindi. or S. divaricatum Sond. as to S. macrocarpum ( Benth.) Erickson & Willis. The geographical and ecological occcurrences of these species are also distinct from one another.
Stylidium macrocarpum is a sand heath species that extends from the Murchison River area southward to Albany ( Erickson, 1958), and is most abundant in the sandplain between Geraldton and Gingin. Stylidium pycnostachyum grows in hardpacked soil of granitic hills near Jurien Bay and in the Darling Range ( Erickson, 1958, and original observations). Stylidium ricae occurs in a small area of granitic outcrops ( the type locality and my collection are in much the same area) , where it is a rock-crevice plant.
In habit, S. ricae forms dense clumps composed of numerous short, thick stems very difficult to extract from rock crevices without digging tools-a habit quite unlike that of S. rnacrocarpum, which has stems simple or branched only a few times (often by means of elongate stems), and which never forms clumps and is therefore easily uprooted from sand. The leaves of S. ricae are exceptionally long, oblanceolate, flat, somewhat concave above with globosely papillate cells on the upper surface. Leaves of S. rnacrocarpum, on the contrary, are shorter, terete, succulent, and have short callous margins near the tips. Leaves of S. divaricatum are like those of S. macrocarpum. Leaves of S. pycnostachyum are broad, obovate, and densely hirsute.
The scapes of S. ricae are more reminiscent of those of S. pycnostachyum or even S. tenuicarpum Carlquist than those of S. macro.carpum. Scapes of S. macrocarpum are subdivaricately branched into complex corymbose portions composed of cymes. In S. ricae, a maximum of three lowermost branches ( often none) are branched, and bear a maximum of three flowers per branch in cymose fashion. Otherwise, the inflorescence would be termed a raceme, for it is clearly monoaxial and the flowers are borne singly on what may be termed branches but have traditionally been termed pedicels ( Mildbraed, 1908;Erickson, 1958) despite the presence of bracteoles. Thus, the inflorescence of S. ricae very closely approaches the "raceme" type. The inflorescence axis upper portions and the ovaries ("calyx tubes") of S. ricae are densely glandular, like those of S. pycnostachyum, whereas  [VoL. 8,No. 4 those of S. macrocarpum are much more sparsely glandular. The scape of S. pycnostachyum bears bracts scattered along its length, including the portion below the lowermost flowers, whereas in S. 1-icae and S. macrocarpum, bracts and bracteoles occur subtending branches and flowers only. Calyx lobes of S. ricae are narrow and acuminate, whereas those of S. macrocarpum and S. pycnostachyum are obtuse. Corolla lobes of S. ricae are pale rose above, deeper rose ( and glandular) below, whereas those of S. macrocarpum are white, streaked red-brown below and those of S. pycnostachyum are white, streaked pink below. Corolla-lobe shape in S. ricae differs somewhat from that of S. macrocarpum, as comparison of my Fig. 29 with figures of Erickson ( 1958) for S. macrocarpum will show. The labellum of S. ricae is like that of S. macrocarpum.
Thus, an appreciable assemblage of features differentiates S. ricae from its closest relatives. Examination of living plants or dried specimens of S. divaricatum demonstrates less similarity to S. ricae than the similarity between S. macrocarpum and S. ricae. If S. ricae were not to be recognized, many other Stylidium species would have to be reduced to infraspecific status also. Because Mrs. Rica Erickson originally discovered this plant and because her work has in large measure stimulated my interest in Stylidiaceae, I take pleasure in naming the species for her. In naming this species for her, I must use her given name, for Willis has commemorated her with S. ericksonae J. H. Willis, a species from Northern Territory. The varietal name given S. ricae by Erickson and Willis ( 1956) cannot be used at the rank of species, for there is already a S. planifolium Poir.
The three species described in this paper reveal no remarkable new feahues for the genus Stylidium, but they do add dimension to the picture of Stylidium as a genus which has responded to "insular" distribution of soil and rock types in southwestern Australia by a remarkable speciation, a speciation that has featured prominently what may be termed vicarious species. ALISO [VoL. 8,No. 4 white flowered, whereas plants at the type locality were yellow flowered ( Carlquist, 1969 quist, 1969) . Revisiting the type locality in 1974, I observed flowers characteristically visited by minute flies , much smaller than those that visit Styliclium species with sensitive columns. I prepared photographs of this fly, which will be published elsewhere. Meanwhile, I would like to augment my description of this species. In the throat of the corolla are four yellowish spots. These may function as false nectar lures for nectarivorous insects. The shiny knobs in corolla throats of various Styliclium species and the shiny disc in the center of the labellum in most Styliclium species almost certainly serve as false nectar lures.

NOTES
STYLIDIUM INVERSIFLORUM Carlquist. This distinctive species, also described from Cadda Road (Carlquist, 1969) ( Erickson and Willis, 1966 ) . Adding these and the three described above, the total becomes 142. Dr. Sidney James ( University of Western Australia) has found that S. elongatum Benth. and S. crassifolium R. Br. differ in level of polyploidy, and he is of the opinion that the two species should be maintained ( personal communication) . I reduced S. elongatum to a subspecies of S. crassifolium ( 1969) . A case might still be made that a population differing by virtue of polyploidy as well as minor morphological differences and geographical distribution could b e regarded as a subspecies, as has been done in other genera. Certainly the two entities are very similar to each other morphologically, whereas other species of Stylidium differ from nearest relatives by a series of well-marked characters. If, however, one chooses to retain S. elongatum as a species, the total number of species for Stylidium considered valid would become 143. New species are to be expected, especially in northern areas of Australia. Of interest within Stylidium, however, is not the precise number of valid species but the modes of speciation ( about 100 spp. are endemic to southwestern Australia) in this remarkable genus.