Scrophulariaceae

Sanjeet Kumar
sanjeet.biotech@gmail.com

The Scrophulariaceae are mostly herbs or sometimes small shrubs comprising about 190 genera and 4,000 predominately temperate species, including many which are partial root parasites (see Castilleja below and Pedicularis) and a few that are without chlorophyll and are wholly parasitic. The leaves are alternate, opposite, or sometimes whorled, and are simple to pinnately dissected; stipules are absent. The flowers are bisexual and zygomorphic, and sometimes have brightly colored and conspicuous associated bracts. The calyx is commonly deeply 4-5 lobed or cleft. The corolla is sympetalous, usually 4-5-lobed, sometimes 2-lipped, and sometimes forms a nectary spur or sac. The androecium consists of 2 or 5 stamens or more commonly of 4 didynamous stamens adnate to the corolla tube or perigynous zone, alternate with the lobes. The gynoecium consists of a single compound pistil of 2 carpels, a single style, and a superior, sometimes asymmetric ovary with 2 sometimes unequal locules, each containing numerous axile ovules. There is usually a unilateral or annular, frequently lobed nectary disk at the base of the ovary. The fruit type is usually a capsule.
Scrophulariaceae, the figwort family, are a family of flowering plants. The plants are annual or perennial herbs with flowers with bilateral (zygomorphic) or rarely radial (actinomorphic) symmetry. Members of the Scrophulariaceae have a cosmopolitan distribution, with the majority found in temperate areas, including tropical mountains. The family name is based on the name of the included genus Scrophularia L..
In the past it was treated as including about 275 genera and over 5,000 species, but its circumscription has been radically altered since numerous molecular phylogenies have shown the traditional broad circumscription to be grossly polyphyletic. Many genera have recently been transferred to other families within the Lamiales, notably Plantaginaceae and Orobanchaceae but also several new families.[2][3] Several families of the Lamiales have had their circumscriptions enlarged to accommodate genera transferred from Scrophulariacae sensu lato.
The family includes some medicinal plants, among them:

Synonyms for family:

Including Antirrhineae (Antirrhinaceae) DC. & Duby, Aragoaceae D. Don, Cheloneae (Chelonaceae) Augier ex Martinov, Calceolariaceae, Diditalaceae Augier ex Martinov, Hebenstreitiaceae Horan., Limoselleae (Limosellaceae) J.G. Agardh, Linderniaceae Borsch, K. Müll.bis & Fisch, Melampyraceae Lindl., Oftiaceae, Paulowniaceae Nak., Pediculares (Pedicularidaceae) Juss., Personaceae Dulac, Rhinanthoideae (Rhinanthaceae) Vent., Schlegeliaceae Reveal, Selaginaceae Choisy, Sibthorpiaceae D. Don, Verbascaceae Nees, Veronicaceae Rafin.Excluding Ellisiophyllaceae, Orobanchaceae
Habit and leaf form. Shrubs and herbs (mostly), or trees, or lianas; non-laticiferous and without coloured juice. Leaves well developed (usually), or much reduced (e.g. the parasitic Harveya, Hyobanche), or absent (?). Plants succulent (somewhat, in Bacopa, Lindernia), or non-succulent; partially parasitic (commonly, concentrated in the Rhinantheae), or autotrophic. Parasitic on roots of the host (when parasitic). Annual, or biennial, or perennial; with a basal aggregation of leaves, or with neither basal nor terminal aggregations of leaves, or with terminal aggregations of leaves (e.g. sometimes in Peplidium). Climbing (sometimes), or self supporting (mainly); the climbers stem twiners, or petiole twiners. Hydrophytic (e.g. ‘Ambulia’, = Limnophila), or helophytic, or mesophytic, or xerophytic (e.g. the ericoid Selagineae); when hydrophytic, rooted. Leaves of aquatics submerged, or emergent, or floating. Heterophyllous (e.g. Hebe, Hydrotriche), or not heterophyllous. Leaves alternate, or opposite, or whorled; when alternate spiral, or four-ranked; ‘herbaceous’, or leathery, or fleshy (rarely), or membranous (rarely); petiolate to sessile, or perfoliate (occasionally); connate (occasionally?), or not connate (usually); sheathing, or non-sheathing; simple; epulvinate. Lamina dissected, or entire; if dissected pinnatifid, or palmatifid, or much-divided (e.g. submerged leaves in Hydrotriche, Limnophila); pinnately veined, or palmately veined. Leaves exstipulate. Lamina margins entire, or crenate, or serrate, or dentate. Leaves without a persistent basal meristem.
Leaf anatomy. Hydathodes present (occasionally), or absent. Stomata present; mainly confined to one surface, or on both surfaces; anomocytic, or anisocytic.
Adaxial hypodermis present (rarely), or absent. Lamina dorsiventral, or isobilateral. Cystoliths present (occasionally), or absent. Minor leaf veins with phloem transfer cells (9 genera, e.g. Antirrhinum, Rhinanthus), or without phloem transfer cells (16 genera, e.g. Pedicularis, Scrophularia, Verbascum).
Stem anatomy. Cork cambium present, or absent; initially when present. deep-seated, or superficial. Nodes unilacunar. Primary vascular tissue usually in a cylinder, without separate bundles; centrifugal. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. Xylem with fibre tracheids, or without fibre tracheids; with libriform fibres, or without libriform fibres; with vessels. Vessel end-walls simple. Vessels without vestured pits. Wood partially storied (VPI, Penstemon), or not storied; parenchyma if present, apotracheal, or paratracheal (usually very sparse or absent). Sieve-tube plastids S-type. Pith with diaphragms, or without diaphragms.
Reproductive type, pollination. Unisexual flowers absent. Plants hermaphrodite. Pollination entomophilous; mechanism conspicuously specialized (with loose-pollen mechanisms), or unspecialized.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’; in cymes, in racemes, in spikes, in heads, and in panicles. The ultimate inflorescence unit cymose, or racemose. Inflorescences terminal, or axillary; mainly racemes, spikes and thyrses, terminal peloric flowers common. Flowers bracteate, or ebracteate; bracteolate, or ebracteolate; minute, or small to medium-sized (mostly), or large; very irregular (usually — apart from peloric terminal flowers), or somewhat irregular (e.g. Verbascum, Bacopa, Elacholoma); resupinate (e.g. in Lindernia hypandra), or not resupinate (usually). The floral irregularity involving the perianth and involving the androecium, or involving the androecium. Flowers neither papilionaceous nor pseudo-papilionaceous; cyclic; tetracyclic. Free hypanthium absent. Hypogynous disk present.
Perianth with distinct calyx and corolla; (6–)8–10(–13); 2 whorled; isomerous, or anisomerous. Calyx 4 (the posterior member missing, or the anterior pair united), or 5, or 2 (e.g. Dischisma); 1 whorled; gamosepalous (usually), or polysepalous (Dischisma, Bacopa); blunt-lobed, or toothed, or entire (sometimes, in Centranthera); unequal but not bilabiate, or bilabiate, or regular; persistent; imbricate, or valvate; when K5, with the median member posterior. Corolla 4 (the posterior pair united), or 5(–8), or 3 (sometimes, in Glossostigma); 1 whorled; appendiculate (e.g. with flaps covering the anthers, in Lindernia), or not appendiculate; gamopetalous; imbricate, or valvate; more or less bilabiate (usually), or unequal but not bilabiate (e.g. Dischisma, where the upper lip is four-lobed and the lower lip is suppressed), or regular (more or less, in Verbascum, etc.); spurred (sometimes), or not spurred; not fleshy; persistent, or deciduous.
Androecium (4–)5 (posterior member sometimes missing), or 2(–3) (sometimes the lower pair reduced or missing). Androecial members adnate (to the corolla); usually markedly unequal; free of one another, or coherent (via the anthers, in Centranthera, Cymbalaria, Elacholoma etc.); 1 whorled. Androecium exclusively of fertile stamens, or including staminodes. Staminodes when present 1 (the posterior member), or 2–3; in the same series as the fertile stamens; representing the posterior median member, or the posterior median member and the posterior-lateral pair. Fertile stamens representing the posterior-lateral pair and the anterior-lateral pair (usually), or the posterior-lateral pair (?), or the anterior-lateral pair, or the posterior median member, the posterior-lateral pair, and the anterior-lateral pair. Stamens (2–)4(–5); inserted near the base of the corolla tube, or midway down the corolla tube, or in the throat of the corolla tube; didynamous (usually), or not didynamous, not tetradynamous; reduced in number relative to the adjacent perianth, or isomerous with the perianth; oppositisepalous; alternating with the corolla members. Filaments appendiculate (sometimes spurred, in Lindernia), or not appendiculate. Anthers cohering, or connivent (in pairs), or separate from one another; dehiscing via pores (Bartsia, some Euphrasia spp.), or dehiscing via longitudinal slits; introrse; unilocular (Selagineae, according to Hutchinson), or bilocular (usually); bisporangiate (e.g. Jamesbrittenia), or tetrasporangiate (usually); unappendaged. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral, or decussate. Anther wall initially with one middle layer, or initially with more than one middle layer (1 or 2); of the ‘dicot’ type. Tapetum glandular. Pollen grains aperturate; 2–7 aperturate; colporate (commonly, or colporoidate), or colpate; 2-celled (in 19 genera).
Gynoecium 2(–3) carpelled. The pistil 2(–3) celled. Gynoecium syncarpous; synstylovarious to eu-syncarpous; superior. Ovary 2(–3) locular. Locules without ‘false septa’. Gynoecium median; stylate. Styles 1; without an indusium; attenuate from the ovary, or from a depression at the top of the ovary; apical. Stigmas 1, or 2; 1–2 lobed; wet type, or dry type; papillate; Group II type and Group III type. Placentation axile, or apical (Selagineae). Ovules 1 per locule (Selagineae), or 2–50 per locule (i.e. to ‘many’); pendulous to ascending, or pendulous (Selagineae); non-arillate; anatropous, or campylotropous, or hemianatropous; unitegmic; tenuinucellate. Endothelium differentiated. Embryo-sac development Polygonum-type, or Allium-type, or Drusa-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 2 (Mimulus, one being binucleate), or 3; not proliferating; ephemeral to persistent. Synergids pear-shaped, or hooked. Hypostase present, or absent. Endosperm formation cellular. Endosperm haustoria present (usually), or absent; when developed, chalazal and micropylar (usually), or chalazal, or micropylar. Embryogeny onagrad, or solanad.
Fruit non-fleshy (usually), or fleshy (rarely); dehiscent (usually), or indehiscent (rarely), or a schizocarp (Selagineae, Lagotis). Mericarps when schizocarpic, 2, or 1 (one often sterile or obsolete in Selagineae). Fruit when non-schizocarpic, i.e. usually, a capsule (usually), or a berry, or capsular-indehiscent (e.g. sometimes in Kickxia). Capsules septicidal (usually), or loculicidal, or poricidal (occasionally), or circumscissile, or splitting irregularly. Seeds endospermic. Endosperm oily. Seeds minute, or small; not conspicuously hairy; winged, or wingless (often angled); without amyloid. Embryo usually well differentiated. Cotyledons 2. Embryo chlorophyllous (3/3), or achlorophyllous (12/26); straight to curved.
Seedling. Germination phanerocotylar.
Physiology, biochemistry. Cyanogenic (rarely), or not cyanogenic. Cynogenic constituents phenylalanine-derived. Alkaloids present, or absent (mostly). Iridoids detected (commonly, including Selagineae); ‘Route I’ type (doubtfully, normal), or ‘Route II’ type (normal and decarb.). Arthroquinones detected (3 genera); derived from shikimic acid. Verbascosides detected (14 genera). Cornoside detected (4 genera). Proanthocyanidins absent. Flavonols to all intents and purposes, absent. Ellagic acid absent (13 species, 9 genera). Saponins/sapogenins present, or absent. Aluminium accumulation not found. Sugars transported as oligosaccharides + sucrose (in Paulownia). C3 and C4. C3 physiology recorded directly in Agalinis, Antirrhinum, Castilleja, Gratiola, Linaria, Lindenbergia, Mimulus, Orthocarpus, Pentstemon. C4 physiology recorded directly in Anticharis. Anatomy non-C4 type (Agalinis, Castilleja, Gratiola, Limnophila, Linaria, Orthocarpus, Penstemon, Scrophularia).
Peculiar feature. The funicles not as in Acanthaceae.
Geography, cytology. Frigid zone to tropical. Cosmopolitan. X = 6 (or more).
Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren’s Superorder Lamiiflorae; Scrophulariales. Cronquist’s Subclass Asteridae; Scrophulariales. APG 3 core angiosperms; core eudicot; Superorder Asteranae; lamiid; Order Lamiales.
Species 3000. Genera about 280; Acanthorrhinum, Achetaria, Adenosma, Agalinis, Agathelpis, Albraunia, Alectra, Allocalyx, Alonsoa, Amalophyllon, Amphianthus, Amphiolanthus, Anarrhinum, Anastrabe, Angelonia, Antherothamnus, Anticharis, Antirrhinum, Aptosimum, Aragoa, Artanema, Asarina, Auriolaria, Bacopa, Bampsia, Bartsia, Basistemon, Baumia, Benjaminia, Besseya, Bowkeria, Brachystigma, Brandisia, Brookea, Bryodes, Buchnera, Bungea, Buttonia, Bythophyton, Calceolaria, Camptoloma, Campylanthus, Capraria, Castilleja, Celsia (= Verbascum), Centranthera, Centrantheropsis, Chaenorhinum, Charadrophila, Cheilophyllum, Chelone, Chenopodiopsis, Chionohebe, Chionophila, Clevelandia, Cochlidiosperma, Collinsia, Colpias, Conobea, Cordylanthus, Craterostigma, Crepidorhopalon, Cromidon, Cycniopsis, Cycnium, Cymbalaria, Cyrtandromoea, Dasistoma, Deinostema, Dermatobotrys, Detzneria, Diascia, Diclis, Digitalis, Dintera, Diplacus, Dischisma, Dizygostemon, Dodartia, Dopatrium, Elacholoma, Encopella, Epixiphium, Eremogeton (or Myoporaceae), Erinus, Escobedia, Esterhazya, Euphrasia, Faxonanthus (or Myoporaceae), Fonkia, Freylinia, Galvezia, Gambelia, Geochorda, Gerardia, Gerardiina, Ghikaea, Glekia, Globulariopsis, Glossostigma, Glumicalyx, Gosela, Graderia, Gratiola, Halleria, Harveya, Hebe, Hebenstretia, Hedbergia, Hemianthus, Hemiarrhena, Hemimeris, Hemiphragma, Hiernia, Holmgrenanthe, Holzneria, Howelliella, Hydranthelium, Hydrotriche, Hygea (or Gesneriaceae), Hyobanche, Ildefonsia, Isoplexis, Ixianthes, Jamesbrittenia, Jerdonia (or Gesneriaceae), Jovellana, Kashmiria, Keckiella, Kickxia, Lafuentea, Lagotis, Lamourouxia, Lancea, Legazpia, Leptorhabdos, Leucocarpus, Leucophyllum (or Myoporaceae), Leucosalpa, Leucospora, Limnophila, Limosella, Linaria, Lindenbergia, Lindernia, Lophospermum, Lyperia, Mabrya, Macranthera, Maeviella, Magdalenaea, Manulea, Manuleopsis, Maurandella, Maurandya, Mazus, Mecardonia, Melampyrum, Melanospermum, Melasma, Melosperma, Micranthemum, Micrargeria, Micrargeriella, Microcarpaea, Microdon, Mimetanthe, Mimulicalyx, Mimulus, Misopates, Mohavea, Monochasma, Monopera, Monttea, Moscheovia, Nemation, Nathaliella, Nemesia, Neogaerrhinum, Neopicrorhiza, Nothochelone, Nothochilus, Nuttallanthus, Odicardis, Odontites, Oftia (or Myoporaceae), Omphalotrix, Ophiocephalus, Oreosolen, Orthocarpus, Otacanthus, Ourisia, Paederota, Paederotella, Parahebe, Parastriga, Parentucellia, Paulownia, Pedicularis, Peliostomum, Pennelianthus, Penstemon, Peplidium, Ptheirospermum, Phygelius, Phyllopodium, Physocalyx, Picria, Picrorhiza, Pierranthus, Polycarena, Porodittia, Psammetes, Pseudobartsia, Pseudolysimachion, Pseudomelasma, Pseudorontiuim, Pseudosopubia, Pseudostriga, Radamaea, Rehmannia, Rhamphicarpa, Raphispermum, Rhinanthus, Rhodochiton, Rhynchocorys, Russelia, Sairocarpus, Schistophragma, Achizosepala, Schizotorenia, Schlegelia, Schwalbea, Schweinfurthia, Scolophyllum, Scoparia, Scrofella, Scrophularia, Selago, Seymeria, Seymeriopsis, Shiuyinghua, Sibthorpia, Silviella, Siphonostegia, Sopubia, Spirostegia, Stemodia, Stemodiopsis, Striga, Strigina, Strobilopsis, Sutera, Synthyris, Teedia, Tetranema, Tetraselago, Tetraspidium, Tetraulacium, Thunbergianus, Tonella, Torenia, Tozzia, Triaenophora, Trieena, Triphysaria, Trungboa, Tuerckheimocharis, Uroskinnera, Vellosiella, Verbascum, Veronica, Veronicastrum, Walafrida, Wightia, Wulfenia, Wulfeniopsis, Xizangia, Xilocalyx, Zaluzianska.
General remarks. For discussion of classificatory problems posed by Scrophulariaceae, impinging on Bignoniaceae, Buddlejaceae, Callitrichaceae, Plantaginaceae, Hippuridaceae, Lentibulariaceae, and Hydrostachydaceae, and such problem genera as Paulownia and Schlegelia, see Olmstead and Reeves (1995), who provide preliminary insights from chloroplast gene sequencing. The implication is that the traditional family Scrophulariaceae comprises two distinct clades, involving numerous other small families; but the question needs pursuing in terms of a much larger sample of genera before practical implementation would be justifiable or feasible. Evidence is accumulating that the Rhinanthoideae should be referred to Orobanchaceae.
Economic uses, etc. Many are poisonous, a few are (e.g. Digitalis) or have been officinal, Halleria has edible fruit (umbinza). Many constitute important ornamentals, and Limnophila (‘Ambulia’) is valuable in aquaria

There are about 2800 species 200 genera of Scrophulariaceae distributed worldwide; many grow in the American Northwest. The name was derived from European species of Scrophularia, the common figwort. The plants were used to treat hemorrhoids, which were known as “figs”. Figworts were also used to treat scrofula, a form of tuberculosis carried in the milk of infected cows. Except for the foxglove (Digitalis), the source of the heart stimulant digitalis, none of the members of this family is of noteworthy economic importance, but many, like the penstemons, are cultivated for their handsome flowers.
The figwort family is characterized by irregular, bilaterally symmetrical flowers with 4-5 sepals, joined to a calyx, and 4-5 petals, joined to a corolla. These often form a tube at the end of which the petals flair outward, the lower ones forming a down turned “lip".
The flowers have two pairs of anther-bearing stamens, and a sterile fifth stamen—a taxonomically important feature. All these parts are attached at the base of the ovary.
The flowers are bisexual and sometimes have brightly colored and conspicuous associated bracts.
The leaves are alternate, opposite, or sometimes whorled, and are simple to pinnately divided. The fruit type is usually a 2-chambered capsule.
In the family Scrophulariaceae are some common hemiparasites, such as Indian paintbrush and owl's clover (Castilleja), lousewort (Pedicularis), and bird's beak (Cordylanthus). These have green, photosynthetic leaves, but a substantial portion of the parasite's carbon is derived from the host plant, parasitized from the roots.
This is a large plant family, with around 3000 species in around 200 genera, mainly found in the northern temperate regions of the world. Most of them are herbaceous, with a few shrubs and climbers, with one genus of trees (Paulownia). Some of them are semi-parasitic (Hay Rattle, Lousewort).
Many of the plants in this Family are popular garden plants - from tiny alpines like Erinus, through Snapdragons (Antirrhinum) and Foxglove (Digitalis) to the Mulleins (Verbascum), and several are well-known weeds - the Speedwells (Veronica), Eyebright (Euphrasia) and the Toadflaxes (Linaria). Other plants in this family grown for ornament include Mimulus, Penstemon, Hebe, and Calceolaria. One or two are grown for the production of drugs, notably Digitalis (Foxglove) for digitalin.
Characteristics of this Plant Family:
Leaves, Stem & Roots ~ Generally, the leaves are opposite or alternate, without stipules, and may be evergreen. Sometimes, they are lobed or cut.
Flowers ~ The calyx under the flowers has five lobes, and the flowers are usually borne in spikes. There are two main flower shapes. Some species (e.g. Veronica), have four petals, but many have irregular shaped flowers with five petals, often joined to form a bell or tube, sometimes with two lips. In some species (e.g. Linaria), there is a long hollow spur with honey to attract pollinators. There are two long and two short stamens attached to the petals.
Seeds ~ The seed capsule in this Family is inside the flower (superior), and has two parts, each with many small seeds.
The angiosperm order Lamiales (sensu Olmstead et al., 1993⇓; Angiosperm Phylogeny Group, 1998⇓) contains several large and well-known families with both tropical and temperate distributions. As traditionally circumscribed (e.g., von Wettstein, 1891), the Scrophulariaceae are the largest of these families and have a worldwide distribution. This family can be distinguished from related families with relative ease. However, it is through the absence of traits characteristic of related families that plants usually are assigned membership to Scrophulariaceae. The characteristics of a typical scroph, including flowers that are bilaterally symmetric and often tubular, ovaries with axile placentation and numerous ovules, capsular fruits, and seeds with endosperm, each are shared with one or several related families. This interpretation has been corroborated by a series of molecular phylogenetic studies of families in the Lamiales (Acanthaceae—Hedren, Chase, and Olmstead, 1995⇓; Scotland et al., 1995⇓; McDade and Moody, 1999⇓; Gesneriaceae—Smith et al., 1997⇓; Lamiaceae—Wagstaff and Olmstead, 1997⇓; Wagstaff et al., 1998⇓; Buddlejaceae—Oxelman, Backlund, and Bremer, 1999⇓; Bignoniaceae—Spangler and Olmstead, 1999⇓), which have determined that many of the related families are monophyletic, thereby suggesting that their distinguishing traits are synapomorphies for those families.
The absence of uniquely defining traits raises the possibility that the Scrophulariaceae are not monophyletic. This was examined by Olmstead and Reeves (1995)⇓, who identified two distinct clades composed of members of the family and suggested that the Scrophulariaceae are polyphyletic. Subsequently, a third clade was identified consisting of the parasitic members of the Scrophulariaceae and Orobanchaceae (dePamphilis, Young, and Wolfe, 1997⇓; Wolfe and dePamphilis, 1998⇓; Young, Steiner, and dePamphilis, 1999⇓). Overlap in sampling between these two studies for taxa in Scrophulariaceae and other families in Lamiales was minimal, leaving open the possibility that these three clades may not all be distinct from each other (e.g., Wolfe and dePamphilis, 1997⇓). Furthermore, the limited sampling of Scrophulariaceae s.l. (sensu lato) in these studies also left open the possibility that there could be additional distinct clades within the traditionally circumscribed family.
Like most large families, the history of the classification of Scrophulariaceae includes many treatments differing in circumscription of the family (see Olmstead and Reeves, 1995⇓) and of suprageneric groupings within the family (see Thieret, 1967⇓; Barringer, 1993⇓). Most contemporary classifications of Scrophulariaceae are derived directly from Bentham's treatments (1846, 1876)⇓. He recognized three subfamilies, Pseudosolaneae, Antirrhinoideae, and Rhinanthoideae. Pseudosolaneae were defined on the basis of traits representing a supposed connecting link with the Solanaceae (nearly regular floral symmetry, alternate phyllotaxis, and presence of a fifth stamen, as in Verbascum). The other two subfamilies were distinguished on the basis of floral aestivation: posterior corolla lobes external to lateral lobes in bud in Antirrhinoideae and vice versa in Rhinanthoideae (Pseudosolaneae was similar to Antirrhinoideae in this respect). Pennell (1935)⇓, citing work by Robertson (1891)⇓ and Robyns (1931)⇓ proposed that the supposed similarities to Solanaceae were actually derived within Scrophulariaceae. Therefore he eliminated subfamily Pseudosolaneae and assigned its genera to Antirrhinoideae (see also Thieret, 1967⇓; Armstrong and Douglas, 1989⇓). Subsequent to Bentham's work, the families Orobanchaceae, Globulariaceae, Selaginaceae, Plantaginaceae, and Lentibulariaceae all have been considered by some authors to be part of the Scrophulariaceae (e.g., Hallier, 1903⇓; Bellini, 1907⇓; Melchior, 1964⇓; Barringer, 1993⇓). In Bentham's initial circumscription (Bentham, 1846)⇓, Buddlejaceae and the zygomorphic members of the Solanaceae were included. Recent molecular studies provide evidence that Myoporaceae and the aquatic families Callitrichaceae and Hippuridaceae belong to clades dominated by scrophs, and they provide further evidence that Buddlejaceae, Globulariaceae, Plantaginaceae, and Selaginaceae also belong in such clades (Olmstead and Reeves, 1995⇓; Reeves and Olmstead, 1998⇓; Wolfe and dePamphilis, 1998⇓; Oxelman, Backlund, and Bremer, 1999⇓).
Our present concern is with the identification of major lineages of plants conventionally assigned to the Scrophulariaceae and their relationship to other lineages of Lamiales. The study reported here represents the integration of two research programs addressing phylogenetic relationships in the Scrophulariaceae and Lamiales. In one, rbcL and rps2 sequences were applied to questions of the evolution of parasitism in the Scrophulariaceae and Orobanchaceae (dePamphilis, Young, and Wolfe, 1997⇓; Wolfe and dePamphilis, 1998⇓; Nickrent et al., 1998⇓). In the other, rbcL and ndhF sequences were applied to questions about the circumscription and phylogenetic placement of Scrophulariaceae in the Lamiales (Olmstead and Reeves, 1995⇓). By expanding the efforts of each group to include data from all three genes for representatives of previously defined clades in Lamiales and suprageneric groups in the conventional Scrophulariaceae, this study attempts to address questions of clade circumscription.
All taxa in our resulting classification represent groups hypothesized to be monophyletic based on the evidence presented here. We provide phylogenetic definitions (deQueiroz and Gauthier, 1992, 1994⇓; Cantino, Olmstead, and Wagstaff, 1997⇓) for those clades that are derived primarily from portions of the traditional Scrophulariaceae.
Source : From Literature

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