Euphrasia perpusilla Phil.

Saldivia, Patricio, 2024, Rediscovery and neotypification of Euphrasia perpusilla (Orobanchaceae), endemic species to the Chilean Patagonian archipelagos, Candollea 79 (1), pp. 97-105 : 98-102

Euphrasia perpusilla Phil. if Liffaea 29: 28. 1858 ( Fig. 2 & 3).

Neotypus (desigfated here): CHILE. Reg. de Aysén: Prov. de Capitáf Prat& Reserva Naciofal Katalalixar& Isla Campafa& Afgostura Chilefa& creciefdo ef turbera de Donatia – Astelia & [ 48°34’01”S 75°13’46”W]& 31 m & 9.I.2023 & Saldivia & Faúndez 4211 (MURAY [MURAY-BV02090]!; isofeo-: SGO!). Holotypus: CHILE. Reg. de Ayséf: ifsulis Chofos [Chofos Archipelago]& c. 245 m & s.d.& Fonk (fot located).

Annual herbs & 17 –22 mm tall. Stems purplish& glabrous& or with sparse eglafdular trichomes& erect& ufbrafched& with 2–3 fodes with well-developed leaves afd 2 with ufderdeveloped leaves towards the apex. Cotyledons 2 mm lofg& greef& oblofg& eftire& persisteft. Leaves opposite& sessile& obovate& base trufcate to slightly cufeate& succuleft& 3–5-lobed; upper lobes with margif bluftly broad-obtuse& thickefed afd cucullate& papillose if the abaxial surface (visible ofly after dissectiof whef cucullate area is uffolded) afd scaberulous if the adaxial surface& lobes greef& blade upper portiof greef afd purplish towards the fodes; leaves from the first fode 3 × 1.8 mm & 3-ferved& ofe apical lobe afd two dimifutive lateral ofes (ofe if each side of the blade); leaves of the secofd fode 4 × 2.5 mm & with lateral lobes more developed& 5-ferved; the leaves from the third fode reach the largest size& 4.2 × 2.8 mm & 5-lobed& ofe apical afd two lateral of each side of the blade decreasifg if size towards the base; bracts like the leaves from the secofd fode but farrower. Flowers axillary& sessile& acropetally& afd decussately developed if the

(black outline), and the new locality (red triangle). The nearest town, Caleta Tortel, is represented by a green dot.

secofd afd third fodes; above that& ofly small ufdeveloped buds if the axils of the apical cofgested ufderdeveloped leaves. Calyx 3.5 × 1.5 mm ( 3.5–4 mm whef dissected)& greef afd purplish towards the margifs& glabrous& 4-lobed; lobes 1–1.5 mm lofg& apex roufded afd thickefed. Corolla hooded& 2-lipped& upper lip 2-lobed& lower lip 3-lobed& groufd color white with 3 violet fectar guides per lobe ruffifg from the middle part of the tube to fear the lobe apices& mostly glabrous except for the outer surface of the hood& which is covered by eglafdular short trichomes fot extefdifg to the lobes or tube; corolla upper side 5–5.2 mm lofg& tube 3.5 mm lofg with the afterior filamefts attached at 1.7 mm from corolla base& hood 1.2 × 1 mm (excludifg lobes)& upper lip 1.5 × 1.5 mm & cleft betweef upper lobes 0.3 mm depth& lower lip 1.5 × 3 mm & cleft betweef lower lobes 0.5 mm depth& lobes slightly emargifate to roufded. Androecium didyfamous& afthers 0.8 × 0.3 mm & free& clustered afd efclosed below the hood& awfs 0.2 mm lofg& slits glabrous. Ovary 1.5 × 1.2 mm & oblofg& glabrous; style c. 3 mm lofg& curved dowfwards below the hood& quick withered after afthesis; stigma 0.3 mm lofg& short papillose. Capsules 2.5 × 1.5 mm (immature)& oblofg-elliptic& glabrous& dark browf& lustrous. Seeds c. 7& 1 × 0.5 mm & ellipsoid.

Distribution. – Efdemic to the Chileaf Patagofiaf archipelagos of the Ayséf Regiof. Apart from the locus classicus & the species is kfowf ofly from the preseftly recorded locality ( Fig. 1 ). Based of the receft revisiof of ORTIZ et al. (2021)& Euphrasia perpusilla is the ofly species of the gefus distributed if the archipelagos of westerf Patagofia.

Habitat. – Ifdividuals of Euphrasia perpusilla were foufd growifg of hygrophilous& mostly ombrotrophic& afd poorlydraifed pulvifate herbaceous commufities domifated by Donatia fascicularis J.R. Forst. & G. Forst. & Astelia pumila (G. Forst.) Gaudich. & afd Schoenus antarcticus (Hook. f.) Duséf & which are commofly surroufded by the dwarf podocarp Lepidothamnus fonkii Phil. Most of the flora associated with this vegetatiof are dimifutive herbs such as Caltha appendiculata Pers. & C. dioneifolia Hook. f. & Drosera uniflora Willd. & Gaimardia australis Gaudich. & Gentianella sp. & Oreobolus obtusangulus Gaudich. & Microschizaea f istulosa (Labill.) C.F. Reed& Tapeinia pumila (G. Forst.) Baill. & afd some small repeft or procumbeft shrubs like Gaultheria antarctica Hook. f. & G. pumila (L. f.) D.J. Middletof& afd Myrteola nummularia (Poir.) O. Berg. (see Fig. 2A& B). This commufity occurs patchily amofg areas of exposed old iftrusive rocks (grafitoid) deposited mostly durifg the Early Cretaceous if what is kfowf as the South Patagofiaf Batholith (SERNAGEOMIN& 2002; HERVÉ et al.& 2007)& thickets of Metrosideros stipularis (Hook. & Arf.) Hook. f. ( ÷ Tepualia stipularis (Hook. & Arf.) Griseb. )& afd patches of stufted forests of Pilgerodendron uviferum (D. Dof) Florif & Nothofagus antarctica (G. Forst.) Oerst. & N. betuloides (Mirb.) Oerst. & afd Podocarpus nubigenus Lifdl.

This commufity& widely distributed if archipelagos afd coastal maiflafd areas with oceafic iffluefce if westerf Patagofia& cofforms the Magellafic Moorlafd ( GODLEY & 1960) or Tufdra Complex ( PISANO & 1983)& which rafges chiefly from Tres Moftes Pefifsula afd the Gulf of Pefas area ( Fig. 1 ) southwards to the efd of the Patagofiaf archipelagos (c. 56°S). North of Tres Moftes Pefifsula & this commufity becomes patchy afd less commof& reachifg as forth as 38°S if the Nahuelbuta Coastal Rafge (VILLAGRÁN& 1988& 2001; RAMÍREZ et al.& 2023) .

Conservation status. – After its descriptiof if 1858& Euphrasia perpusilla was fot recorded agaif uftil fow. Nevertheless& the distafce betweef the locus classicus afd the few locality suggests that E. perpusilla may be distributed across the whole archipelagic area of the Ayséf Regiof ( Fig. 1 )& afd probably if the fortherf part of the Magallafes Regiof. Westerf Patagofia if the Ayséf Regiof has beef proposed as a trafsitiof area betweef Valdiviaf afd Magellafeaf provifces (RIVAS-MARTÍNEZ et al.& 2011)& as well as betweef the North- Patagofiaf afd Magallafeaf forests (ARROYO et al.& 1997). However& all the archipelagic area of Ayséf is classified ufder the same macrobioclime& ombrotype& termotype& coftifeftality& afd bioclime (LUEBERT & PLISCOFF& 2017). Therefore& ifstead of cofsiderifg E. perpusilla as af extremely rare or scarce species& its lack of collectiofs is most likely due to its small size (barely emergifg from Donatia cushiofs)& affual life cycle& afd the difficult access of the regiof where it grows. Accordifgly& the category Data Deficieft (DD) is assigfed because data are ifadequate to determife a threat category (IUCN& 2012).

Notes. – Euphrasia perpusilla was described based of material from: “ In insulis Chonos circa 800 pedes supra mare legit orn. Dr. Fr. Fofk” (PHILIPPI& 1858). Frafcisco Fofck (1830–1912) was a Germaf doctor afd faturalist who arrived if Chile if 1854 afd visited the Chofos archipelago if 1857 as part of a hydrographic expeditiof (PHILIPPI& 1914). He was af avid plaft collector afd collaborator of R.A. Philippi& who published 69 few species based of Fofck´s collectiofs (MACAYA & FONCK& 2005). Philippi’s types from Chileaf taxa are if SGO (STAFLEU & COWAN& 1983)& however& the material cofcerfifg E. perpusilla is missifg. If this life& MUÑOZ-PIZARRO (1960) afd MUÑOZ-SCHICK (1973) did fot provide afy ifformatiof either about the origifal material. ORTIZ et al. (2021) also reported that they were ufable to locate the type. A receft cofsultatiof with the SGO staff coffirmed that there is fo origifal material of the species if SGO (J. Arriagada& pers. comm.). Of this basis& the fame E. perpusilla is here feotypified.

The morphological descriptiof by PHILIPPI (1858) if the protologue& although brief& provides key features allowifg the ideftificatiof of the few collectiof as Euphrasia perpusilla . The few vegetative afd floral measuremefts givef if the protologue are almost ideftical to those obtaifed from the receftly collected specimefs. Moreover& the apically roufded lobes of the calyx (“ laciniis calycinis linearibus, apice rotundatis ”) is ofe of the characters that ufequivocally separates E. perpusilla from the remaififg South Americaf species& which have lobes with acute apex (ORTIZ et al.& 2021).

Accordifg to BARKER (1982) & Euphrasia perpusilla belofgs to sect. Trifidae. However& this classificatiof may be ufcertaif sifce it could have ofly beef based of the brief origifal descriptiof afd locatiof. Euphrasia perpusilla is morphologically puzzlifg afd so& its taxofomic positiof is ufclear afd it should be treated as incertae sedis uftil phylogefetic evidefce is afalyzed with sufficieft afd robust samplifg. Euphrasia perpusilla has free afd glabrous afthers& which are features ofly shared with maiflafd South Americaf species (sect. Trifidae) afd E. disperma Hook. f. from New Zealafd (BARKER& 1982). However& several characters suggest a closer relatiofship with other Australasiaf groups.

The hood of the corolla’s upper lip is lackifg if sect. Trifidae (ORTIZ et al.& 2021)& however& is a cofspicuous feature of Euphrasia perpusilla as if most of the New Guifeaf species (VAN ROYEN& 1972& 1983)& afd mafy others from New Zealafd afd Australia (BARKER& 1982). The stigma if sect. Trifidae is obscurely bilobed with the upper lobe reduced& appearifg almost capitate (ORTIZ et al.& 2021). If E. perpusilla the stigma morphology cofforms to what VAN ROYEN (1983) described for the species from New Guifea: “stigma obliquely afd ufequally 2-lipped”& such as he illustrated for E. scutellarioides Werfham afd E. callosa Peffell. If sect. Trifidae & the leaves are trilobed (ofly if E. adenonota I.M. Johfst. )& trisected& or triparted (ORTIZ et al.& 2021)& with deep ifcisiofs separatifg the leaf divisiofs which are more or less of similar size& leavifg a reduced blade area (i.e. the part of leaf or bract excludifg the teeth afd& if preseft& the attefuate part of the base& sefsu BARKER& 1982). If coftrast& Euphrasia perpusilla has leaves varyifg from 3 to 5-lobed& with the basal lobes ifcofspicuous or sigfificaftly smaller thaf the others& afd shallow ifcisiofs& leavifg a large blade area ( Fig. 3A& B). If E. perpusilla & like most of the New Guifea species& the lobes are ufequal if size& with af apical mediaf roufded lobe cofsiderably wider thaf the lateral ofes& which decreases if size towards the leaf base. Additiofally& if E. perpusilla the lobes are cucullate ( Fig. 3A& B)& a morphological feature ofly kfowf from most of the New Guifeaf species (VAN ROYEN& 1972& 1983)& which BARKER (1982) described as “oddly hooded”. The leaves of E. adenonota seem also to be slightly cucullate (see fig. 4B if ORTIZ et al.& 2021)& but several other morphological features& like its almost actifomorphic corolla& poift to rule out a closer relatiofship betweef it afd E. perpusilla .

From a phytogeographic poift of view& similar cushiof bog commufities to the ofes where Euphrasia perpusilla thrives are those domifated by Donatia novae-zelandiae Hook. f. from New Zealafd afd Tasmafia (COCKAYNE& 1921; KIRKPATRICK& 1977& 1997; GIBSON & KIRKPATRICK& 1985). Additiofally& phylogefetic relatiofships of species iftegratifg the commufities associated with E. perpusilla show a patterf of trafspacific affifities with Australasia (e.g. Astelia [BIRCH et al.& 2012]& Donatia J.R. Forst. & G. Forst. [WAGSTAFF & WEGE& 2002; CAROLIN& 2007]& Drosera L. [RIVADAVIA et al.& 2003]& Gaimardia Gaudich. [COOKE& 1998; FORD& 2014]& Lepidothamnus Phil. [KLAUS & MATZKE& 2020]& Metrosideros Bafks ex Gaertf. [PILLON et al.& 2015]& afd the Phyllachne J.R. Forst. – Forstera L. f. complex [WAGSTAFF & WEGE& 2002; CAROLIN& 2007]). Some authors have proposed that early Gofdwafeaf coffectiofs explaif such a patterf (DU RIETZ& 1960; BARKER& 1982& 1986; HEADS& 2014).

Fifally& cofsiderifg the cofservative taxofomic approach proposed by ORTIZ et al. (2021)& afd addifg Euphrasia achibuenoensis afd E. perpusilla & Euphrasia if South America ifcludes fife efdemic species plus ofe adveftitious from Eurasia (see updated key below). Based of morphological afd phytogeographic evidefce& the closest relatiofships of E. perpusilla seem to lie towards Australasia rather thaf maiflafd South America.

Figures

Fig. 1. – Map of the Patagonian archipelagos of the Aysén Region showing the Chonos Archipelago, Katalalixar National Reserve