Tubular Corolla Research Articles

New hypotheses of phylogenetic relationships in Barnadesioideae (Asteraceae) based on morphology

SummaryUrtubey, E. & Stuessy, T. F.: New hypotheses of phylogenetic relationships in Barnadesioideae (Asteraceae) based on morphology. ‐ Taxon 50: 1043–1066. 2001. — ISSN 0040–0262.Previous molecular sequence and restriction site data have confirmed subfamily Barnadesioideae as basal within Asteraceae. The subfamily consists of 88 species in nine genera: Arnaldoa, Barnadesia, Chuquiraga, Dasyphyllum, Doniophyton, Duseniella, Fulcaldea, Huarpea, and Schlechtendalia. Two morphological cladistic analyses among genera or subgeneric groups within this subfamily have been completed previously, with contrasting results. Because of the importance of understanding relationships in this group of early Asteraceae, especially for insights on character evolution within the family, comprehensive morphological cladistic analyses were conducted at the specific level. Initial investigations utilising 31 characters with all 88 species led eventually to curtailed studies with 52 species. Five different outgroup hypotheses were employed: Acicarpha laxa, A. spathulata, Calycera leucanthema, C. spinulosa (all Calyceraceae), and Schlechtendalia luzulaefolia (Barnadesioideae; as functional outgroup). The results confirm Schlechtendalia as basal within Barnadesioideae. Monophyly is also confirmed for all genera, sections Chuquiraga and Acanthophyllae of Chuquiraga, and subgenus Archidasyphyllum of Dasyphyllum. All cladograms show two major groups (although statistical support values are low): (1) Chuquiraga, Doniophyton and Duseniella; and (2) Arnaldoa, Dasyphyllum, Fulcaldea, Huarpea and Barnadesia. Although bilabiate (4+1) corollas occur in Schlechtendalia, tubular corollas are believed plesiomorphic for the subfamily because they are pervasive in Calyceraceae as well as in all other basal Barnadesioideae. Pollen with no shallow depressions also are hypothesised as plesiomorphic for Barnadesioideae, even though one depression occurs in Schlechtendalia. A southern South American origin of Barnadesioideae (and the entire family) is re‐emphasised. The previously hypothesised ancient lineage of Dasyphyllum subg. Archidasyphyllum, consisting of large trees, appears more derived in the new analyses.

Pollination ecology of Tabebuia aurea (Manso) Benth. & Hook. and T. ochracea (Cham.) Standl. (Bignoniaceae) in Central Brazil cerrado vegetation

The pollination ecology and breeding systems of Tabebuia aurea (Manso) Benth. & Hook., and T. ochracea (Cham.) Standl. were investigated in an area of cerrado vegetation in the Federal District of Brazil. These species occur sympatrically, flower massively and synchronously for a month, during the dry season (July to September). Both have diurnal anthesis, with similar floral structures, a yellow tubular corolla and produce nectar. Fourteen species of bees visited both Tabebuia species, but, only three Centris species and Bombus morio, were considered potential pollinators, because of their high frequency on the flowers and their efficiency in carrying pollen. Tests on the breeding systems of T. aurea and T. ochracea demonstrated that boths species are self-incompatible, with late-acting self-incompatibility. The proportion of fruit set from cross pollination (T. aurea 17.2% and T. ochracea 12.3%) in both species was low considering the great number of flowers displayed. This suggests a lack of maternal resources for fruit-set. The great amount of seeds per fruit (about 92 in T. aurea and 285 in T. ochracea) may represent an investment of maternal resources allocated on higher quality of fertilized ovules.

A preliminary analysis of the phylogeny of the Swertiinae (Gentianaceae) based on ITS data

To better understand the floral diversity and the phylogeny of the Swertiinae (Gentianaceae), the internal transcribed spacer (ITS) region of nrDNA for 17 species and one outgroup was sequenced. Our data suggest that corolla type, gland shape, and corolla appendage are poorly correlated with the ITS phylogeny. The genus Swertia s.l. and the rotate group previously recognized based on the corolla types and gland shapes are polyphyletic. Four genera with simple protruding glands and three taxa with corolla appendages are not clustered as the monophyletic groups. Four separate clades, corresponding to the four sections, were identified in Swertia s.l. Lomatogoniopsis with the simple protruding gland type of the tubular group closely related to Lomatogonium of the rotate group. The deeply lobing corolla and concave foveae may be ancestral in the Swertiinae, while the tubular corolla and the protruding glands may have undergone convergent evolution.

Three New Species of Jaltomata (Solanaceae) from Ancash, Peru

Three new Jaltomata species from the department of Ancash, Peru, are described and illustrated. The three species are distinguished from others in the genus by features of the flowers, hairs, and leaves. Fruits of Jaltomata cajacayensis S. Leiva & Mione are gathered for consumption. Jaltomata lomana Mione & S. Leiva is known only from a single fog-dependent plant community, a lomas formation. Jaltomata yungayensis Mione & S. Leiva is widely distributed at high elevations. Species of Jaltomata have simple, often geminate leaves, 5-merous flowers with rotate to campanulate or tubular corollas, and a bicarpellate ovary housing numerous ovules. The inflorescence is umbellate; anthers dehisce longitudinally and the ovary is girdled by a disk at its base. The berry, orange or red on most South American species and dark purple to black on most Central American species, is not enclosed by the calyx and is often edible (Leiva, 1998; Mione, 1992). The genus includes about 50 herbaceous and shrubby species distributed from Arizona, U.S.A., to Bolivia, with one species each on the Galapagos Islands and Greater Antilles (Mione et al., 1993). These descriptions of three new species are a contribution to ongoing systematic studies of this genus (e.g., Mione, 1999; Mione & Leiva, 1997). MATERIALS AND METHODS The compound light microscope was used for measurement of stalked glands and stigma papillae; flowers placed in 70% ethanol in Peru were used. The sizes of structures as indicated by the scale bars in the figures may differ somewhat from the sizes given in the descriptions because alcohol-preserved flowers were used for drawing, while dried specimens were used for measurements. Seeds of J. lomana were not available for study. Trichomes are not gland-tipped unless indicated as such. Finger hairs are uniseriate, unbranched, and multicellular. Branchlet hairs (Fig. 3B) have multiple termini (Seithe, 1979). A gland-tipped finger hair has a bulbous terminal cell (Fig. 1C) that stains densely with neutral red, as does the multicellular head of a stalked gland (illustrated in Mione & Serazo, 1999). Jaltomata cajacayensis S. Leiva & Mione, sp. nov. TYPE: Peru. Ancash: Bolognesi, highway from Pativilca to Recuay and Huaraz, km 90, town of Cajacay, 2540 m, open sun, roadside with Agave andina and Carica candicans, 18 Jan. 1998, T Mione, S. Leiva G. & L. Yacher 624 (holotype, NY; isotype, CONN). Figure 1. Planta fruticosa; axes juvenes, folia, faciesque abaxialis calycis obtecta pilis indivisis apice glandiferentibus; folia ovata vel deltata, ad 9 cm longitudine, 10 cm latitudine, petiolo ad 3.2 cm longitudine; inflorescentia floribus 14 ut maximum; calyx 13 mm diametro maturitate fructus; corolla brevissime, tubulosa, limbo reflexo 10.3-19.2 mm diametro, olivacea; filamenta villosa secus proximales 4/5 partes longitudinis; bacca aurantiaca, ad 9 mm diametro. Shrub to 1.1 m high. Young axes, peduncles, pedicels, and abaxial faces of calyx villous with erect, gland-tipped finger hairs to 3 mm long. Woody stems glabrous, terete, to at least 1.5 cm diam. Leaves alternate, often geminate, the blade ovate or deltoid, to 9 x 10 cm, pubescence of gland-tipped finger hairs on both faces, the margin repand, sinuate or dentate with up to 5 pairs of broad, rounded teeth; petiole to 3.2 cm long. Inflorescence axillary or less commonly arising from a NovoN 10: 53-59. 2000. This content downloaded from 207.46.13.176 on Fri, 16 Sep 2016 06:00:46 UTC All use subject to http://about.jstor.org/terms

Floral Symmetry and Its Influence on Variance in Flower Size.

The evolutionary shift from radial symmetry (actinomorphy) to bilateral symmetry (zygomorphy) in flowers is generally viewed as an important step in the 140-millionyear history of the flowering plants (Stebbins 1974; Gifford and Foster 1988; Coen et al. 1995). The appearance of zygomorphy occurred independently on multiple occasions (Tucker 1984) and has led to the evolution of highly specialized pollination systems seen in advanced families such as the Orchidaceae and Scrophulariaceae (Neal et al. 1998). Largely because flower architecture and symmetry affects pollinator behavior, evolutionary modifications of the primitive, radially symmetrical angiosperm flower influenced the specificity of interactions between plants and their pollinators (Stebbins 1950). Zygomorphic flowers typically have fused tubular corollas with a single plane of symmetry. This floral architecture offers pollinators a limited number of physical orientations that may be adopted for correct flower handling. Consequently, feeding and pollination may be more difficult and require a higher degree of precision. In contrast, actinomorphic flowers have two or more planes of symmetry (Luo et al. 1996) and are considered simpler structures for pollinators to handle. As a result, effective pollination can be achieved by a wider range of animal species in actinomorphic flowers (Cronk and Moller 1997; Richards 1997). The adaptive significance of symmetry and pollinator specificity results from the greater efficiency of pollen transport (Faegri and van der Pijl 1979; Ingrouille 1992). Because the effectiveness of pollen transport depends on

Functional, evolutionary and ecological aspects of feeding-related mouthpart specializations in parasitoid flies

This paper considers mouthpart specializations for feeding among dipteran parasitoids, and places them in both an evolutionary and an ecological context. Parasitoid flies display specializations in relation to feeding on solidified honeydew, removing floral nectar from long, narrow, tubular corollas, and feeding on host materials. No species have as yet been identified which display particular specializations for pollen-feeding, but we consider it likely that they exist. Marked sexual dimorphism in mouthpart structure appears to occur only in the Phoridae. Mapping the occurrence of apparatus for removing floral nectar from long, narrow, tubular corollas (‘concealed nectar extraction apparatus’ or CNEA) onto published cladograms for Diptera shows that the evolution of such feeding apparatus has occurred many times independently. In contrast to parasitoid Hymenoptera, possession of CNEA is more often an autapomorphy for taxa above subfamily level in apparently two cases for superfamilies (Acroceroidea and Nemestrinoidea). We conclude that whereas in parasitoid wasps the pattern of occurrence of CNEA is mainly attributable to ecological expediency, in parasitoid flies phylogenetic history has also played a major role. We discuss the fitness advantages of the different feeding specializations among parasitoids generally (i.e. both Diptera and Hymenoptera) in relation to various ecophysiological factors.

Functional, evolutionary and ecological aspects of feeding-related mouthpart specializations in parasitoid flies

This paper considers mouthpart specializations for feeding among dipteran parasitoids, and places them in both an evolutionary and an ecological context. Parasitoid flies display specializations in relation to feeding on solidified honeydew, removing floral nectar from long, narrow, tubular corollas, and feeding on host materials. No species have as yet been identified which display particular specializations for pollen-feeding, but we consider it likely that they exist. Marked sexual dimorphism in mouthpart structure appears to occur only in the Phoridae. Mapping the occurrence of apparatus for removing floral nectar from long, narrow, tubular corollas (‘concealed nectar extraction apparatus’ or CNEA) onto published cladograms for Diptera shows that the evolution of such feeding apparatus has occurred many times independently. In contrast to parasitoid Hymenoptera, possession of CNEA is more often an autapomorphy for taxa above subfamily level in apparently two cases for superfamilies (Acroceroidea and Nemestrinoidea). We conclude that whereas in parasitoid wasps the pattern of occurrence of CNEA is mainly attributable to ecological expediency, in parasitoid flies phylogenetic history has also played a major role. We discuss the fitness advantages of the diVerent feeding specializations among parasitoids generally (i.e. both Diptera and Hymenoptera) in relation to various ecophysiological factors.

Functional and evolutionary aspects of mouthpart structure in parasitoid wasps

This paper considers specializations in mouthpart structure among parasitoid wasps. I commence with a brief survey of mouthpart specializations (mostly involving the mandibles only) that serve functions other than feeding: facilitating emergence of the parasitoid adult from its place of pupation; facilitating grasping of the partner in mating (phoretic copulation); facilitating excavation and/or protecting vulnerable mouthpart components during host searching; facilitating handling of the host; and facilitating nest excavation and construction. I then consider in detail mouthpart specializations for feeding (mostly involving the labiomaxillary complex), and place them in an evolutionary context. Whereas the digitate labrum of Perilampidae and Eucharitidae and the stoutly setose labrum of chrysolampine Pteromalidae are purported to be devices for filtering pollen grains from nectar, I conclude that they are not a feeding-related specialization whatsoever. I recognize seven functional types of mouthpart specialization relating to the extraction of floral nectar from long, narrow, tubular corollas (‘concealed nectar extraction apparatus’ [CNEA]) (Braconidae, Ichneumonidae, Leucospidae, Chrysididae), and postulate a transformation series for them. An eighth type of CNEA possibly occurs in Scoliidae. No such specializations occur in either Orussoidea, Trigonalyoidea, Megalyroidea, parasitoid Evanioidea, Stephanoidea, Cynipoidea, Proctotrupoidea, Ceraphonoidea or parasitoid Aculeata other than Chrysididae and Pompilidae. From examination of published cladograms I conclude that the evolution of CNEA has occurred several times independently within the parasitoid Hymenoptera. So far as Ichneumonoidea are concerned, possession of CNEA is an autapomorphy for taxa at least below subfamily level. Possession of CNEA appears to be a synapomorphy for the family Leucospidae (Chalcidoidea) as a whole, and the same applies to the subfamily Parnopinae (Chrysididae). Hitherto not noted in the literature is the strong degree of evolutionary parallelism, with respect to CNEAs, between the Ichneumonoidea (Ichneumonidae, Braconidae) and the Aculeata (Chrysididae, Pompilidae, Vespidae [Vespinae, Masarinae, Eumeminae], Apidae, non-parasitoid Sphecidae). Also, Apocrita and Symphyta have two types of CNEA in common. Functional comparisons are made between the CNEAs of the parasitoids and those of other Hymenoptera. Compared to parasitoid flies, very few parasitoid wasps possess CNEA. Mouthpart specialization for conveying a nuptial gift of nectar or honeydew to the female occurs in the males of thynnine Tiphidae, while in the females of regurgitation feeders there is a trend towards reduction in labiomaxillary components, constituting a specialization for receiving and processing the gift. Mouthpart specialization for pollen feeding occurs in Mutillidae and Scoliidae. No mouthpart specialization for host feeding occurs in any parasitoid wasps, in contrast to parasitoid flies, despite host feeding being more common among the former. Sexual dimorphism in feeding-related mouthpart specializations is rare among parasitoid wasps; where it occurs, both sexes share the same type of CNEA, and the dimorphism is attributable to allometry.

Functional and evolutionary aspects of mouthpart structure in parasitoid wasps

This paper considers specializations in mouthpart structure among parasitoid wasps. I commence with a brief survey of mouthpart specializations (mostly involving the mandibles only) that serve functions other than feeding: facilitating emergence of the parasitoid adult from its place of pupation; facilitating grasping of the partner in mating (phoretic copulation); facilitating excavation and/or protecting vulnerable mouthpart components during host searching; facilitating handling of the host; and facilitating nest excavation and construction. I then consider in detail mouthpart specializations for feeding (mostly involving the labiomaxillary complex), and place them in an evolutionary context. Whereas the digitate labrum of Perilampidae and Eucharitidae and the stoutly setose labrum of chrysolampine Pteromalidae are purported to be devices for filtering pollen grains from nectar, I conclude that they are not a feeding-related specialization whatsoever. I recognize seven functional types of mouthpart specialization relating to the extraction of floral nectar from long, narrow, tubular corollas (‘concealed nectar extraction apparatus’ [CNEA]) (Braconidae, Ichneumonidae, Leucospidae, Chrysididae), and postulate a transformation series for them. An eighth type of CNEA possibly occurs in Scoliidae. No such specializations occur in either Orussoidea, Trigonalyoidea, Megalyroidea, parasitoid Evanioidea, Stephanoidea, Cynipoidea, Proctotrupoidea, Ceraphonoidea or parasitoid Aculeata other than Chrysididae and Pompilidae. From examination of published cladograms I conclude that the evolution of CNEA has occurred several times independently within the parasitoid Hymenoptera. So far as Ichneumonoidea are concerned, possession of CNEA is an autapomorphy for taxa at least below subfamily level. Possession of CNEA appears to be a synapomorphy for the family Leucospidae (Chalcidoidea) as a whole, and the same applies to the subfamily Parnopinae (Chrysididae). Hitherto not noted in the literature is the strong degree of evolutionary parallelism, with respect to CNEAs, between the Ichneumonoidea (Ichneumonidae, Braconidae) and the Aculeata (Chrysididae, Pompilidae, Vespidae [Vespinae, Masarinae, Eumeminae], Apidae, non-parasitoid Sphecidae). Also, Apocrita and Symphyta have two types of CNEA in common. Functional comparisons are made between the CNEAs of the parasitoids and those of other Hymenoptera. Compared to parasitoid flies, very few parasitoid wasps possess CNEA. Mouthpart specialization for conveying a nuptial gift of nectar or honeydew to the female occurs in the males of thynnine Tiphidae, while in the females of regurgitation feeders there is a trend towards reduction in labiomaxillary components, constituting a specialization for receiving and processing the gift. Mouthpart specialization for pollen feeding occurs in Mutillidae and Scoliidae. No mouthpart specialization for host feeding occurs in any parasitoid wasps, in contrast to parasitoid flies, despite host feeding being more common among the former. Sexual dimorphism in feeding-related mouthpart specializations is rare among parasitoid wasps; where it occurs, both sexes share the same type of CNEA, and the dimorphism is attributable to allometry.

Floral Biology and Bat Pollination in Pilosocereus catingicola (Cactaceae) in Northeastern Brazil

Within the Cactaceae, various genera have been reported as being bat-pollinated, including Pilosocereus, however actual observations have not been reported from Brazil. In this work we investigate the floral biology and pollination of Pilosocereus catingicola (Gurke) Byles & Rowley subsp. salvadorensis (Werderm.) Zappi, a species endemic to North-eastern Brazil, where its common name is ‘facheiro’. Observations of the pollination biology of this species were made in the coastal sand-dunes of Paraiba. The flowers of P. catingicola have various characteristics associated with bat-pollination; widely opening tubular corolla greenish white in colour, foul odour, high and continuous production of nectar and nocturnal anthesis. The flowers open after 6 p.m., the stamens disposed around the interior of the corolla-tube, the style lying along the lower edge of the tube, the stigma exserted and receptive during the night, from the beginning of anthesis until the flower closes around 7 a.m. the following morning. The production of nectar is copious and continuous from the beginning of anthesis, averaging 440 µl, and is stored in the nectar-chamber. The average concentration of sugar in the nectar was 23%. Visits of a phylostomid bat, Glossophaga soricina, at regular intervals of approx. 10–40 min. were observed, which suggested trap-lining behaviour, favouring cross-pollination. Occasional visits of hawkmoths were also observed, which may also function as effective pollinators. P. catingicola is a self-incompatible species, whose seed production depends on crosspollination through the presence of a pollen vector.

Pollination and flower diversity in scrophulariaceae

The flowers of the Scrophulariaceae show a great diversity in form, especially of the corolla. The most common pollinators are bees collecting nectar, pollen, or oil; other pollinators are moths and butterflies, hummingbirds, syrphid flies, and (in one case) ants. The occurrence of bell-shaped corollas in most tribes of the Scrophulariaceae and in related families indicates that this is the basic (ancestral) flower form. Derived from it are narrow tubular corollas, wide flaring ones, corollas closed to unsuitable visitors by a palate (an upcurving of the tube), corollas forming a keel around the style and anthers either on the upper or lower side of the flower, corollas inflated to form a balloon, and corollas with one or two spurs. Convergences due to selection by the same or similar pollinators limit the usefulness of most of these floral features in analyzing the systematic relationships of the tribes of the Scrophulariaceae. Nevertheless, their diversity of forms exemplifies the evolutionary potential of fused perianth parts.

587 PB 126 MICROPROPAGATION OF SPIGELIA MARILANDICA (L.) L.

Spigelia marilandica, an herbaceous perennial native to the temperate eastern United States, has great potential for the sunny garden due to a fairly long flowering period-and long (3.5-5.5 cm) tubular corollas that are scarlet on the outside and yellowish within. Non-wild collected seeds were disinfested using conventional procedures, and after 8 wk at 4°C, four seeds germinated in vitro. Preliminary experiments examined seedling lines (# 1, 2, 5 and 6) and media (MS versus DKW.) Line 6 was found to be consistently more proliferative over a six month period. Trend analysis demonstrated no difference in total number of axillary shoots produced on full versus 1/2 MS media. MS-derived microcuttings were chlorotic but appeared to root better than DKW-derived microcuttings.

Novae Gesneriaceae Neotropicarum V. Four New Species and Two New Combinations in Columnea from South America

A monographic study of sections Pentadenia and Stygnanthe of Columnea (Gesneriaceae) has revealed four species new to science and two new combinations. These species are described here and include C. atahualpae and C. hypocyrtantha of section Pentadenia, and C. manabiana, C. suffruticosa, C. ultraviolacea, and C. xiphoidea of section Stygnanthe. Columnea L. is a genus of neotropical plants distributed from southern Mexico to Bolivia comprising approximately 200 species. Species of Columnea are readily distinguished by their long tubular corollas that are either bilabiate or ventricose, and the fleshy, indehiscent, berry fruits. The majority of species are epiphytic, although several can be terrestrial as well. A revision of the species of Columnea in Ecuador conducted by Kvist & Skog (1993) and a treatment of the Gesneriaceae of Panama by Skog (1979) are the only recent taxonomic treatments of the genus. Wiehler (1973, 1983) divided the genus into four segregate genera and described a fifth genus allied to the Columnea complex. These five genera were combined back into the single genus Columnea by Kvist & Skog (1993). The four new species described here are the result of a monographic study of two of the smaller sections of Columnea, sections Pentadenia and Stygnanthe (Smith, 1991). The two new combinations result from a recent publication of new species of Gesneriaceae (Wiehler, 1992). Columnea (section Pentadenia) atahualpae J. F. Smith & L. Skog, sp. nov. TYPE: Ecuador. El Oro: forest along trail from Sambotambo, following headwaters of Rio Moro Moro S to Buenaventura, at and along highway to Portovelo, 29 Aug. 1943, Steyermark 54228 (holotype, F). Figure 1. NOVON 3: 186-197. 1993. Differt a Columnea nervosa (Klotzsch ex Oersted) Hanstein foliis ellipticis vel obovatis bracteis magnis corollis brevis (3.0-3.3 cm longis) marginibus integris trichomatibus appressis aureis. Suffrutescent terrestrial (or possibly epiphytic) herbs with erect stems to 1 m tall (Fig. 1A). Stems 8-12 mm diam., tawny brown, apex appressed pubescent with golden yellow uniseriate trichomes, lower stem smooth and glabrous. Internodes 2.5-9.0 cm long, leaf scars slightly raised from the slightly swollen nodes. Leaves opposite, equal to subequal, blades obovate to elliptic, 9.2-22.5 x 3.7-7.8 cm, apex acute, base cuneate-oblique, adaxially green, strigose-appressed pilose with single-celled, transparent, and uniseriate golden yellow trichomes, abaxially silvery green-maroon, vestiture similar to adaxial surface but sparser, pubescence of veins abaxially sericeous, margin entire to slightly undulate (Fig. 1A, B). Petioles 1.0-3.2 cm, appressed pilose with uniseriate golden yellow trichomes. Inflorescences 1-7 flowers in axils of either leaf pair (Fig. 1A), floral bracts 1-2 of unequal size, lanceolate-ovate, 8-22 x 1.5-16 mm, apex acuminate, slightly constricted at base, reddish, appressed pilose with uniseriate golden yellow trichomes, margin entire. Pedicels 1.3-1.9 cm, erect in leaf axil, appressed pilose with uniseriate golden yellow trichomes, 1-several glands present on pedicel, purplish, ca. 0.4 mm long. Calyx clasping corolla at base but more open toward apex of lobes, lobes lanceolate-subulate, equal in size, 1.5-2.7 x 0.30.5 cm, apex long acuminate, green with red tips to purple, margins serrulate-subulate, 3-5 teeth per side, mostly basal, exterior sericeous with uniseriate golden yellow trichomes, interior surface similar but trichomes sparser (Fig. 1C). Corolla pale yellow, tubular, gibbous at base, slightly ventricose, 3.03.3 cm long, 3.0 mm wide at base, 5-8 mm at widest point, 4-5.5 mm before limb, exterior apThis content downloaded from 157.55.39.151 on Fri, 29 Jul 2016 04:57:25 UTC All use subject to http://about.jstor.org/terms Volume 3, Number 2 1993 Smith & Skog Columnea

A New Species of Senecio Section Dichroa (Asteraceae-Senecioneae) from Brazil

Senecio serranus from Parana, Brazil, is described as new. It is related to Senecio dichrous (Bong.) Schultz-Bip., but does not have glandular hairs and does have leaves of the same color on both surfaces. Both species belong to Senecio sect. Dichroa Cabr. and unlike all other ones of the section, have rayless heads with only one type of floret. Among the collections made by Gert Hatschbach in the state of Parana, Brazil, there is an undescribed species of Senecio related to Senecio dichrous (Bong.) Schultz-Bip. but without glandular hairs and with leaves not paler on lower surface than on upper, which is here described. Senecio serranus Zardini, sp. nov. TYPE: Brazil. Parana: Campina Grande do Sul, Serra Capivari Grande, 6 Mar. 1969, Hatschbach 21212 (holotype, MBM; isotypes, MO, US not seen, distributed as Senecio dichrous). Figure 1. Herba erecta; caule striato profunde sulcato glabro ca. 1 m alto. Folia petiolata alterna; lamina glabra oblonga, basi attenuata, apice acuta, margine grosse dentata, nervis reticulatis. Capitula multa discoidea ad apices ramulorum paniculato-corymbosa; involucro campanulato glabro calyculato ca. 9 mm alto ca. 6 mm crasso; bracteolis calyculi 4-6, lanceolatis, 9-13 mm longis; phyllariis 6-8, oblongolinearibus, apice acutis. Flosculi ca. 26, lutei, isomorphi, hermaphroditi; corolla tubulosa ca. 10 mm longa, pentadentata. Achaenia (immatura) costata glabra ca. 6 mm longa; pappo albo capillari ca. 10 mm longo. Erect herb. Stems striate, furrowed, glabrous, 1 m tall. Leaves petiolate, alternate. Blade oblong, attenuate at base, acute at apex, coarsely dentate at margin, with reticulate venation, glabrous or sometimes with evanescent arachnoid tomentum below. Heads many, discoid, in terminal inflorescences paniculate-corymbose. Involucre campanulate, glabrous, 9 mm tall, 6 mm wide, with epicalyx; bracts of the epicalyx 4-6, lanceolate, 9-13 mm long; phyllaries 6-8, linear-oblong, acute. Florets around 26, yellow, isomorphic, hermaphrodite, with tubular corolla 10 mm long, 5-lobed. Achenes (immature) ribbed, glabrous, 6 mm long. Pappus white, capillary, 10 mm long. Paratypes. BRAZIL. PARANA: Campina Grande do Sul, Pico Caratuva, 8 Feb. 1968, Hatschbach 18563 (MBM, MO); Serra Capivari Grande, 18 July 1986, Silva & Zelma s.n. (US not seen, distributed as Senecio dichrous). Senecio serranus Zardini is similar to S. dichrous (Bong.) Schultz-Bip. (basionym, Cacalia dichroa Bong. Brazil. Minas Gerais: Riedel s.n., holotype, LE not seen, photo, MO; see Fig. 2), from which it can be differentiated by the following key. la. Plants without glandular hairs; leaves of the same color on both surfaces ........ S. serranus Ib. Plants with glandular hairs; leaves distinctly paler on lower surface, green above, whitish below S. dichrous These two species belong to Senecio sect. Dichroa, one of the two sections of the genus characterized by a hairy tuft at the apex of the style. The description of this section (Cabrera, 1957) should be amended to include rayless heads with only one type of floret characteristic of both Senecio serranus and S. dichrous. The latter species was treated by Cabrera (1957) within section Dichroa as doubtful because the type of its basionym, Cacalia dichroa Bong., was not seen by him. All the other species of the section have heads with two types of florets, the marginal ones being ligulate. Acknowledgments. I express special gratitude to G. Hatschbach (MBM), to N. Imkhanitskaya of the Komarov Botanical Institute (LE) for help with the study of the type of Cacalia dichroa Bongard, and to A. Cabrera (LP) for reviewing the manuscript.

Explosive flower opening in ornithophily: a study of pollination mechanisms in some Central African Loranthaceae

In many ornithophilous Loranthaceae pollination is accompanied by an explosive opening of the flowers, and diverse mechanisms have evolved in different genera to bring this about. These are described for the African genera Erianthemum, Englerina, Tapinanthus, Globimetula, Vanwykia and Plicosepalus. In many genera tensions within the stamens cause the tubular corolla to split along the petal junctions to form window-like fenestrae. The flowers are pollinated mainly by sunbirds which insert their beaks through the fenestrae in search of the abundant nectar. This action causes the tube to split and the stamens to coil inwards explosively. In Globimetula and many species of Tapinanthus pigment is secreted along the edges of the specialized petal segments of the head, the spathulae. Probing along these secretory junctions causes the spathulae to reflex; further probing splits the corolla tube, and allows the stamens to coil inwards explosively. In Globimetula reflexure of the petals exposes the central column of stamens, between which secondary fenestrae are developed. In Plicosepalus curvature of the corolla tube is connected with a more specialized fenestral structure; flower opening is not explosive, and the open flowers continue to be visited regularly by sunbirds. In Vanwykia an early stage in the development of explosive flower-opening is found.

Nectar thievery by ants from southern Spanish insect-pollinated flowers

Correlates of ant nectarivory have been investigated in a sample of 75 insect-pollinated, nectar-producing southern Spanish plant species. Ants exploit floral nectar opportunistically. Variation among plant species in sugar secretion rates and flower location relative to ground level do not influence either the chances of ant visitation or the identity of ant species involved. Mechanical restrictions on nectar accessibility (tubular corollas, occlusive structures) decrease nectar thievery, Some evolutionary trends in floral morphology usually related to a decrease in the range of effective pollinators alone may simultaneously be interpreted in terms of increased plant adaptedness to exclude non-pollinating insect nectarivores.

Pollination Specialization and Protogyny in Myrrhidendron donnellsmithii (Umbelliferae)

Myrrhidendron donnellsmithii is a woody, andromonoecious member of the apioid Um- belliferae indigenous to Costa Rica. Hermaphrodite flowers are protogynous and concentrated in the outer umbellets of secondary umbels, while the primary and tertiary umbels consist almost entirely of male flowers. Neither hermaphrodite nor male flowers open fully, the petals remain erect with their tips strongly infolded, and together with the filaments form a floral tube, the base of which surrounds the nectariferous stylopodium. This tubular corolla probably excludes non- adapted flower visitors, but allows access to nectar by longer-tongued, specialized pollinators such as those seen visiting the umbels. As the staminal filaments form an integral part of the floral tube, protogyny is probably the most advantageous dichogamous system, because delay of male function postpones disruption of the tube following anther dehiscence.

Effects of trophic morphology and behavior on foraging rates of three Hawaiian honeycreepers.

The effects of trophic morphology and behavior of three Hawaiian honeycreepers (Fringillidae: Drepanidinae) upon their foraging rates on the flowers of Vaccinium calycinum are examined. The Maui Creeper (Paroreomyza montana), the Amakihi (Hemianathus virens), and the I'iwi (Vestiaria coccinea) show shifts from a short straight bill to a long decurved bill, from a tongue adapted for insect feeding to one specialized for nectar, and diets ranging from primarily probing for insects to primarily nectarivorous. This diversity is examined feeding on the simple straight tubular corollas of the Vaccinium. Significant differences (P<0.001, t-tests) exist among the birds with respect to foraging rates on these flowers. The I'iwi, with its greatly decurved (64°) bill feeds the quickest (2.09 s/flower) while the Maui Creeper with its rather straight (18°) bill feeds the slowest (3.87 s/flower). These differences are seen to be the result of differing abilities of tongues to extract nectar as well as differing behavioral tactics of floral exploration and nectar extraction. This suggests that predictions of foraging efficiency based solely on bill morphology are not necessarily valid, and that other factors (tongue morphology, foraging maneuvers, and typical food spectrum) must also be considered.

Ants Like Flower Nectar

Ants Like Flower Nectar

Floral Mechanics in Phlomis (Lamiaceae)

Closed corollas that have to be opened by pollinators form a protection of pollen or nectar against adverse weather conditions or against thieves, e.g. in many mask-, gulletor flag-blossoms. Only occasionally thieves can reach the pollen (Brantjes, 1980) or the nectar (Knoll, 1922) through the entrance of such flowers. Usually, thieves perforate the corolla. The legitimate pollinator has to be able to open the flowers and, as can be concluded from the occurrence of closed flower types, mostly in plant species with mellitophilous characters, the opening capacities seem to be restricted to bees (Hymenoptera). These bees vary considerably in size and also in power. This has implications for their abilities to handle a particular flower species, e.g. to trip flag-blossoms of the Fabaceae, among which are many crop plants. We designed a means of studying the mechanical aspect of the flower-pollinator interactions and chose a flower ( Phlomis fruticosa L., Lamiaceae) pollinated by what are said to be the strongest bees: Carpenter bees ( Xylocopa spp.) (Van der Piji, 1972). Pallas (1973), working under the supervision of Van der Piji, confirmed that in Tessalie (Greece) Xylocopa violacea was the only nectar drinker and a successful pollinator of Phlomis fruticosa . In the botanical garden, Hortus de Wolf, Haren, Netherlands, where the present experiments were carried out, Carpenter bees are absent. Occasional bumblebees operate the flowers and therefore, acted as 'stand in'. Bracts surround the bases of the aggregated flowers, presumably forming a protection against puncturing nectar robbers (Van der Piji, 1972). The corolla consists of a tube, a lower lip and an upper lip. The strongly recurved lower lip has a median groove and two lateral lobes [Fig. 1(a), (b)]. The profile gives much of the strength to the lower lip, which does not deform under the pressure produced by the visitors. A broad hinge part connects the hood-like upper lip on to the corolla tube [Fig. 1(a), (b), (d), (e)]. The proximal part of the hood is compressed laterally with only its outer parts diverging [Fig. 1(b), (f)]. The sides of the strongly-inflated distal part of the hood touch each other [Fig. 1(a), (g)]. The top of this part bears a longitudinal fold [Fig. 1(b), (g)]. In the tubular corolla the stamen filaments are continuous with the corolla wall [Fig. 1(c)]. Just below the hinge the filaments separate from the corolla and arch inside the curve of the hood. Thin curled hairs interconnect the four filaments to form a stiff bundle [Fig. 1(e), (f)], which sits confined in a groove above the lateral compression [Fig. 1(e), (f)]. In the top part of the corolla tube the style lies between ridges formed by the filament bases. In the hood, the style is situated between the filaments until its proximal part extends beyond the corolla [Fig. 1(a), (b)]. In this position the stigma will touch the visitor before the anthers do, and self pollination seems to be prevented. The plant was found to be self compatible in Greece, but outcrossing will be the rule because of the