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Sarraceniainsectivorous plants show a diversity of visual features in their pitchers but their perception by insects and their role in attraction, have received little attention. They also vary in prey composition, with some species trapping more flying Hymenoptera, such as bees. To test the hypothesis of a link between visual signal variability and prey segregation ability, and to identify which signal could attract flying Hymenoptera, we characterised, the colour patterns of 32 pitchers belonging to four taxa, modelled their perception by flying Hymenoptera, and examined the prey they trapped. The pitchers of the four taxa differed in colour patterns, with notably two long-leaved taxa displaying clear areoles, which contrasted strongly in colour and brightness with the vegetative background and with other pitcher areas in the eyes of flying Hymenoptera. These taxa trapped high proportion of flying hymenoptera. This suggests that contrasting areoles may act as a visual lure for flying Hymenoptera, making plants particularly visible to these insects. Prey capture also differed according to pitcher stage, morphology, season and visual characteristics. Further studies on prey visitation are needed to better understand the link between prey capture and attraction feature.

Background and Aims In hierarchically reticulate venation patterns, smaller orders of veins form areoles in which stomata are located. This study aimed to quantify the spatial relationship among stomata at the areole level. Methods For each of 12 leaves of M. cavaleriei var. platypetala, we assumed that stomatal characteristics were symmetrical on either side of the midrib, and divided the leaf surface on one side of the midrib into six layers equidistantly spaced along the apical–basal axis. We then further divided each layer into three positions equidistantly spaced from midrib to leaf margin, resulting in a total of 18 sampling locations. In addition, for 60 leaves, we sampled three positions from midrib to margin within only the widest layer of the leaf. Stomatal density and mean nearest neighbour distance (MNND) were calculated for each section. A replicated spatial point pattern approach quantified stomatal spatial relationships at different distances (0–300 μm). Key Results A tendency towards regular arrangement (inhibition as opposed to attraction or clustering) was observed between stomatal centres at distances Conclusions Spatial inhibition might be caused by the one-cell-spacing rule, resulting in more regular arrangement of stomata, and it was found to exist at distances up to ~100 μm. This work implies that leaf hydraulic architecture, consisting of both vascular and mesophyll properties, is sufficient to prevent important spatial variability in water supply at the areole level.

Summary We report a female Chordodes anthophorus from a Giant Asian Mantis (Hierodula membranacea) for the first time from Iran. Scanning electron microscopy (SEM) was used to describe the characters and substructures precisely. We demonstrate characteristic cuticular patterns for Chordodes anthophorus. The presence of five types of areoles including simple, tubercle, crowned and circumcluster areoles and also crowned areoles with long fi laments which is a common feature in females, confi rm our investigation.

Background. Degos acanthoma is rare benign tumor. Typical signs of this disease are localization on the lower limbs, abdomen and anterior chest in middle-aged and elderly patients (50–70 years old). The only one clinical case of pale cell acanthoma with the atopic dermatitis, and eczema in the area of areoles in the 26 years old patient was described.Clinical Case Description. The boy had redness and swelling in the area of the right mammary gland at the age of 11 years. This mass lesion was regarded as the eczema of the areola region due to burdened allergic history (atopic dermatitis), thus, antihistamine therapy was prescribed. Similar lesion has appeared in the area of the left areola 3 months later, the same therapy was used. Saniopurulent discharge was occasionally noted from the lesions. The child was consulted by dermatologist, endocrinologist and surgeon at the place of residence, and diagnosed with chronic purulent mastitis. Conservative therapy had no positive dynamics. Bilateral changes in areoles were revealed during hospitalization at the age of 13 years. There were red lesions with non-homogenous surface, yellow discharge, hyperemia around the right areola. The lesion sizes were 2.03.0 cm on the left and 3.03.5 cm on the right side. Biopsy has revealed pale cell acanthoma. Conservative treatment with oral and systemic glucocorticosteroids was prescribed, positive dynamics was obtained for 3 days after the therapy initiation.Conclusion. The presence of eczema in the area of the nipple associated with sanioserous discharge requires the differential diagnosis with pale cell acanthoma. The conservative therapy (with glucocorticosteroids) efficacy for pale cell acanthoma is shown.

A comparative study of the some leaf anatomical features of four species of Annona occurring in Nigerian was undertaken with the aid of light microscope. The four foliar structures (epidermis, petiole, midrib and lamina architecture) studied revealed useful characters which support recognition of the species. A combination of these features has been used to prepare an artificial indented dichotomous key for identifying the species. The generic constant features encountered included hypostomata, paracytic stomatal type, linear nerves endings, uneven midrib outline, and centrally located vascular bundles in the petiole and midrib. However, the most reliable distinguishing characters found across the species included presence of brachyparacytic stomata in A. reticulata, presence of trichomes on the midrib in A. senegalensis, absence of druses on the abaxial surface in A. muricata and A. squamosa, a thick pitted anticlinal walls on the surfaces of A. muricata and consistent polygonal areola shape in A. squamosa. The overlapping characters which also justify the closeness of the species and their grouping in a genus were recorded in both the qualitative and quantitative features. Prominent among them are the mean stomatal width which is about 1.0 μm in all species, nerve endings within the areole which varies between 1-2, U- or V-shaped midrib on the adaxial surface and straight to curved anticlinal wall pattern. The significance of these observations is discussed in updating the existing data in the genus. Keywords: Epidermis, Microscopy, Midrib, Petiole, Systematic

In Morocco, despite the adaptation of the prickly pear cactus (Opuntia spp) to edaphoclimatic conditions, differing from those that prevail in the countries from which it originates, this introduced species is regressing due to biotic and abiotic stresses that impact its survival. Hence, finding innovative technologies to preserve this species are essential. However, the success of in vitro micropropagation technologies is hinged upon the initial disinfection step. In this work we have tested several solutions and exposure time mixtures for disinfection across three different explants, as well as the adoption of hormonal combinations for the induction/regeneration step that allow for efficient micropropagation of cacti. We aimed to produce healthy regenerable vitroplants capable of effectively preserving themselves under aseptic conditions. We describe a specific protocol based on the type of areoles: (1) cladode without areolas (CWA); (2) areolas with shredded glochids (ASG); and (3) areolas with intact glochids (AIG). For each of these areoles, the disinfectant concentration and contact time were optimized and various hormonal combinations were tested for induction/regeneration. The optimal design meeting I-optimality criterion was used to predict the optimal combination by maximizing desirability. The disinfection combination that used 4.23% calcium hypochlorite (w:v), 0.4% Tween 20 (v:v), and 10 minutes of exposure time reduced the contamination frequency to 0.002% with a necrosis rate of less than 0.33% in explants with AIG. This type was the only one that gave responses in the induction/regeneration phase, which allowed us to predict the best rate of caulogenesis (71.74%) under a hormonal combination of 5.3 mg/L of BenzylAminopurine (BAP) and 0.59 mg/L of 1-Naphthaleneacetic acid (ANA). Furthermore, the highest callogenesis rate of 94.45% was obtained by a hormonal combination of 6 mg/L of BAP and 0.59 mg/L of ANA. The explant’s rhizognesis was carried out with a concentration of 0.5 mg / l ANA, before acclimatization on a substrate containing soil and sand in a ratio of 3:1. In conclusion, these protocols provide easy and cost-effective means to multiply cacti in vitro to preserve them in areas where their culture has been destroyed by cochineal.

Amastia refers to a condition where breast tissue, nipples, and areoles are congenitally absent, and it can affect one (unilateral) or both (bilateral) breasts. Congenital amastia is a rare condition with only 34 reported cases in the literature. In this case, we report a 17-year-old female with congenital unilateral amastia of the right breast. She came to our clinic due to a cosmetic view of this defect, which was bothering her, and greatly reducing the overall quality of her life. Our patient's physical examination revealed the absence of right breast, and there was no other obvious physical or anatomical abnormality. The defect was successfully reconstructed in three steps. Firstly, 200 cc adipose tissue was transferred under the skin before inserting the breast implant due to increasing the thickness between the skin and the nipple-areola. Secondly, after four months breast implant was inserted. Finally, the patient's right nipple-areola complex (NAC) was reconstructed with a skate flap.

Yellow pitahaya is an exotic fruit that is rich in essential nutrients and antioxidants. In Colombia, it grows naturally in warm areas, but it is not clear which species exist because this genus presents a lot of intra and interspecific hybridization. More studies are needed in this field along with characterizations of the genotypes. This study aimed to undertake an in situ morphoagronomic evaluation of yellow pitahaya genotypes from five municipalities in Boyacá, Colombia. Measurements were taken in a completely random design. Qualitative and quantitative descriptors for cladodes, fruits and covered production systems were evaluated with a descriptive analysis, Spearman correlation variance, and multivariate and cluster analysis. The results showed that cladode characteristics such as cladode width, distance between areoles, number of spines, length of areoles, margin ribs of cladode and waxiness could be used to identify Megalanthus spp. Characteristics such as weight (270–274 g), size (100 mm), color of the fruit and pulp as well as acidity (0.18) and soluble solids (15.7) were highly variable between the genotypes. Genotypes with good morphological and fruit characteristics were identified (Gen2 and Gen9), which can provide the bases for the selection of pitahaya that satisfy the needs of farmers and consumers.

Characterization and evaluation of the available gene pool is essential for Opuntia ficus-indica taxonomy and improvement. Taxonomically, continued efforts are still needed to elucidate the complexity of this species. The partial or total absence of spines was the most important feature for distinguishing species in the genus Opuntia. Spinelessness is desired outcome for breeding strategies of livestock forage. Thus, a major challenge is to understand the variation in the spininess trait within naturalized accessions of this species. In the present work, morphological characterization of 20 naturalized accessions from a range of Algerian steppe sites was conducted. Thirty qualitative and quantitative features of cladodes, areoles and spines were studied. These features were then subjected to One Way ANOVA, Hierarchical Ascending Classification (HAC) and a correlation study. It was found that both forms (spiny and spineless) showed slight differences in qualitative features of cladodes, areoles and spines. Quantitative studies revealed the existence of four groups (one spineless and three spiny groups). The first spiny group has more than two spines per areole, the second with two spines and the third spiny group with at most one spine per areole. Variation within spiny accessions showed the existence of an intermediate group composed of the second and the third spiny group; suggesting that some accessions of these groups were spineless and became spiny under stress conditions. Correlations showed that some cladode and spine features were significantly influenced by minimum temperature and annual rainfall. More detailed physiological, genetic and molecular studies are recommended to understand spininess variation, occurrence and disappearance.

Cylindropuntia leptocaulis cuttings produce new long-shoots from portions of cuttings that are both aboveground and belowground. New long-shoots arising aboveground appear normal, of the same size and morphology as the original cutting. New longshoots arising belowground, however, are ultra-thin (< 1mm diameter), approximately one-eighth the diameter of the already thin cuttings, have smaller redder photosynthetic leaves, and have hairs growing from their areoles, none of which have been previously reported. Long-shoots arising from belowground quickly grow wider, with normal green fleshy leaves, and non-hairy areoles after growing a few centimeters aboveground.

Opuntia species express great intraspecific morphological variability. All reproductive structures, cladodes (stem segments), and spines respond to macroenvironmental and microenvironmental variation and all of these form from areoles (axillary buds). However, little is known about areole response to light and temperature differences. In this study, I determined whether Opuntia areole numbers and spacing respond to environmental conditions. Terminal cladodes of Opuntia littoralis (Cactaceae) were sampled in Southern California. Data were collected for pad length, pad width, number of areoles on one pad face, number of areoles on the other pad face, and the distances to the nearest areole from the center one on one pad face and on the other for each pad for each of the four orientation groups (N-S, E-W, NW-SE, or NE-SW) for a total of 24 variables. Two-way analysis of variance, related-samples Wilcoxon signed rank tests, and Pearson product-moment correlation identified relationships across and between variables. Results show that areoles are a rather stable feature with regard to environmental variation; there were only small differences on cladode faces oriented in opposite directions. Areoles do not show the more dramatic responses to environmental variation typically seen on the structures borne from those areoles (such as cladodes and spines).

The genus Opuntia has its place in order Caryophyllales of Angiosperms. This group of evergreen, succulent perennial plants belongs to the family Cactaceae. The Opuntia genus is native to Central America, having approximately 181 known species. These species flourish in dry, warmer, and open areas. They are cultivated throughout the world as not only vegetable, crop, and food products like jams, juices, and beverages but used as fodder and forage in Brazil, Mexico, Northern and southern Africa, and in Western Asia. In the early stage, the cladodes are tender and used as a vegetable source known as Nopales, while its fruit is obovoid to spheroidal known as tunas. It is juicy and fleshy used in candies. They are considered alternative natural medicine in diabetes, colon cancer, obesity, gastric ulcers, and coronary heart diseases. The Opuntia species hybridize easily in the wild, leading to continuous morphological variations results in misclassifications. The present study aims to complete the morphological description (qualitative and quantitative) of Opuntia species characterized by flattened cladodes called pads, covered with areoles with tiny detached spines known as glochids. The flowers are mostly yellow, cup-shaped, and lack true petals. The species showed noteworthy differences among color, length, the diameter of cladodes, spines per areole, flower, and fruit shape and color. The Opuntia genus is one of the most ignored plants’ genera, and this morphological characterization overcomes insufficient and inadequate knowledge for its species-level distinction.

Lophophora williamsii is an ornamental slow growth cactus highly appreciated by cacti growers and hobbyists. Its demand is often satisfied through illegal collection of wild plants and many populations are threatened with extinction. Thus, an efficient in vitro protocol without plant growth regulators will be of great interest for conservation purposes of this cactus. Eight different germination media, combining Murashige and Skoog medium (MS, full and half-strength), sucrose (20 and 30 g L−1) and agar (8 and 10 g L−1), were used to study germination rate, number of seedlings with areoles and initial seedling development. Germination rates among culture media only differed significantly in the first 14 days after sowing (DAS), reaching 67–75% at the end of the assay (49 DAS). Remarkable interactions among media components were detected, and 20 g L−1 sucrose and 8 g L−1 agar combination gave the highest performance for both size and number of areoles. Following germination assay, a growth assay was conducted during 105 days using three growth media (GrM) at different sucrose concentration (15, 30 and 45 g L−1) to evaluate the increase in seedling size and number of areoles. Regardless of their initial size, 15 g L−1 sucrose provided the best results for both traits. Size increase was higher in the 4–5 mm seedling group, while increase in areoles was greater in 2-3 mm seedlings. It was possible to develop an in vitro protocol, in absence of plant growth regulators, which allows maximizing L. williamsii germination and growth during its first stages of development, which may increase the availability of plants in the market and avoid exhaustion of wild populations. Furthermore, plants grown ex situ could be reintroduced in endangered natural populations.

Metamasius spinolae es un insecto fitófago que ataca las estructuras vegetativas de algunos géneros de la familia Cactaceae. El objetivo del trabajo es dar a conocer los hábitos florívoros y frugívoros de M. spinolae. Entre 2017 y 2018, observaciones mensuales se realizaron para registrar la incidencia de ataque de este coleóptero y describir el daño en las estructuras vegetativas y reproductivas de Opuntia cantabrigiensis. Metamasius spinolae tiene hábitos herbívoros al consumir cladodios jóvenes y areolas. Este insecto es un florívoro que consume parcialmente el perianto y elimina el gineceo de los botones. El daño impide la reproducción exitosa de los individuos. Este insecto actúa como frugívoro al alimentarse de la pulpa de los frutos maduros. Lo importante es apreciar la conducta depredadora de M. spinolae debido a que su hábito alimenticio no solo se restringe a las estructuras vegetativas de los hospederos que ataca.

Neoraimondia have short-shoots comprised of a large areole with indeterminate growth (‘Kurztriebcephalien’). Flowers of some other cacti are subtended by modestly large photosynthetic leaves. Many specimens of the organ pipe cactus, Stenocereus thurberi, seem to have all these traits: large short-shoots with indeterminate growth and fleshy photosynthetic leaves. Short-shoots in organ pipe cactus grow new photosynthetic leaves at their apical meristem and sometimes flower, branch, and form discrete areoles with new spines. However, unlike short-shoots in Neoraimondia, spherical short-shoots of Stenocereus thurberi seem to retain chlorenchyma and lack extensive cork development.

Opuntia setocarpa, a nopal from state of Jalisco is described and illustrated. The species belongs to the series Criniferae Pfeiffer. It is distinguished by its cladodes with papillose epidermis, small and close together areoles, the areoles of cladodes, pericarpel and fruits with white long bristles, these becoming caducous. Information about its habitat is provided and its relationship with the closest species is discussed.

Involucropyrenium breussii A. B. Gromakova et S. Y. Kondr., a new lichen species for science, is described from eastern Ukraine, illustrated and compared with closely related taxa. It is similar to I. tremniacense from which it differs in having smaller thalline areoles, narrower rhizohyphae, a medullary layer differentiated in the centre of areoles, and longer ascospores. A short description of plant communities in which Involucropyrenium breussii was found in Ukrainian steppes with chalk outcrops is provided.

Leptocereus demissus Areces, from the dry limestone terraces of Pedernales province, southwestern Dominican Republic, is newly described and compared with its local relative, the widespread L. weingartianus. The chiefly 5–6-ribbed new taxon is distinguished from the latter species in its consistent scandent-like habit, its slender and drooping stem segments with straight to slightly dentate ribs lacking swollen podaria in their growing apices, its striking flowers with obconical receptacle-tubes that are not constricted above and below the nectar chamber (vs. narrowly tubular flowers that are distinctly constricted), and its spinier fruits with larger, persistent areoles, each bearing to 25 stiff spines that grow as the fruit matures, overlapping by their tips the spines of adjacent areoles. Because the 4-ribbed holotype of L. weingartianus — only referred to as coming from Haiti- was destroyed in 1943, a neotype of this species is hereby designated.

Opuntia ficus indica (L.) is interesting; it is used as forage, medicinal plant and as food (sweet fruits). Moreover, the cacti involve the CAM photosynthetic pathway which allows great water-use efficiency. In Algeria, despite their vegetative propagation, the wild accessions of this species showed significant diversity. In order to evaluate this diversity, 20 accessions of O. ficus indica L. were collected from different bioclimatic localities in Algeria. Morphological characterization of these accessions was performed. Thirty one qualitative and quantitative morphological features of six cladodes per accession were studied (measured or observed), then subjected to one-way analysis of variance (ANOVA), the principal component analysis (PCA) and the factorial correspondence analysis (FCA). The factorial analysis of the qualitative features separates the accessions into two forms (spiny and spineless). The bioclimatic effect on these features was negligible. However, ANOVA and PCA analysis of quantitative features allowed detecting a significant diversity within and between accessions. Spiny forms showed high variation in comparison to spineless forms; thus, under bioclimatic effect, three spiny groups were illustrated. This illustration allowed detecting a gradual variation of the following features: aptitude and length of spine, number of spine per areole, number of areole per face and cladode width. A significant correlation was found between these features and the classical Emberger's pluviometric quotient (Q2). The results presented in this paper confirmed our hypothesis about the existence of a gradual variation of the spines and areoles traits, which seems to be a response to the bioclimatic effect.

Three new species are described and another is recognized in Campyloneurum. Two species occur in Mexico to El Salvador and the others two are present in Nicaragua, Costa Rica and Panama. The new species are Campyloneurum acutum A. Rojas, C. leoniae A. Rojas and C. madrense A. Rojas. The first species differs from C. xalapense by broader rhizome scales, acute to attenuate blade apex, commonly two series of areoles between parallel veins, commonly one sori per areole and hydathodes absent or few evident. Campyloneurum leoniae differs from C. irregulare by more compact and non-pruinose rhizomes, thinner stipes, relatively broader, thinner and more opaque laminae, and distribution at lower elevations. Campyloneurum madrense is different to C. angustifolium because it has narrower and darker rhizome scales with denticulate margin, long scales cells and distributed at lower elevations. Finally, Campylonerum pittieri is here recognized as valid species and it differs from the similar C. amphostenon by longer rhizomes with appressed scales that have a patent, long acuminate apices, relative broader laminae, veins evident and distribution at higher elevations.

Using 227 dicotyledonous species in temperate region, we found the relationships among densities of different-order veins, creating diversity of leaf vascular architectures. Dicotyledonous angiosperms commonly possess a hierarchical leaf vascular system, wherein veins of different orders have different functions. Minor vein spacing determines leaf hydraulic efficiency, whereas the major veins provide mechanical support. However, there is limited information on the coordination between these vein orders across species, limiting our understanding of how diversity in vein architecture is arrayed. We aimed to examine the (1) relationships between vein densities at two spatial scales (lower- vs. higher-order veins and among minor veins) and (2) relationships of vein densities with plant functional traits. We studied ten traits related to vein densities and three functional traits (leaf dry mass per area [LMA], leaf longevity [LL], and adult plant height [Hadult]) for 227 phylogenetically diverse plant species that occur in temperate regions and examined the vein–vein and vein–functional traits relationships across species. The densities of lower- and higher-order veins were positively correlated across species. The minor vein density was positively correlated with the densities of both areoles and free-ending veins, and vascular networks with higher minor vein density tended to have a lower ratio of free-ending veins to areoles across species. Neither densities of lower- nor higher-order veins were related to LMA and LL. On the other hand, the densities of veins and areoles tended to be positively correlated with Hadult. These results suggest that densities of different-order veins are developmentally coordinated across dicotyledonous angiosperms and form the independent axis in resource use strategies based on the leaf economics spectrum.

Lophocereus (Pachycereus) schottii has lignified thorns with secondary growth connecting areoles to the vascular cylinder, which may help support their massive highly parenchymatous shoots.

One of the most remarkable features of Cactaceae are the areoles, axillary outgrowths, which produce trichomes, spines and leaves. The subfamily Opuntioideae K. Schum. shows the widest diversity of transition forms between leaves and spines, which represents anatomical evidence that spines and glochids are modified leaves. The purpose of this paper is to provide an anatomical description of the areolar structure in four species of Opuntioideae, in order that new anatomical homology between spines/glochids and leaves may be clarified. Different patterns of areole morphology are observed: 1) Austrocylindropuntia subulata (Muehl.) Backeb. showing terete and persistent leaves; areoles with persistent spines, glochids and trichomes; 2) Opuntia monacantha (Willd.) Haw. with terete caducous leaves and persistent spines, glochids and trichomes; 3) Opuntia rufida Engelm. with terete deciduous leaves and areoles with glochids and trichomes; and 4) Opuntia microdasys (Lhem.) Pfeiff. with early caducous leaves and areoles showing trichomes and leaf-spine and leaf-glochid transition forms. The development of the areolar structures is very similar in all species, following the description of the literature for other Cactaceae Juss. In O. microdasys is described a new anatomical character in the family: mucilage cells in the leaf-glochid transition forms, which may have functional importance for water storage in species devoid of persistent leaves.

There are problems with previous attempts to define ‘cephalium’, such as via production of more hairs and spines, confluence of areoles, or periderm development at or underneath each areole after flowering. I propose using the term ‘cephalium’ only for a combination of these criteria, i.e. flowering parts of cacti that have confluent hairy or spiny areoles exterior to a thick periderm, where these hairs, spines, and periderms arise almost immediately below the shoot apical meristem, and with more hairs and spines on reproductive parts than on photosynthetic parts of the shoot. Periderm development and confluent areoles preclude photosynthesis of cephalia, which therefore lack or mostly lack stomata. There is almost always a discrete transition from photosynthetic vegetative tissues to a non-photosynthetic flower-bearing cephalium, both of which arise from the same shoot apical meristem. Cephalia have different phyllotaxy than vegetative parts of the shoot and appear to be on top of existing vegetative phyllotaxy. If flowering parts only have a subset of the above characteristics of cephalia, then I propose calling these structures ‘pseudocephalia’.

Although spine variation within cacti species or populations is assumed to be large, the minimum sample size of different spine anatomical and morphological traits required for species description is less studied. There are studies where only 2 spines were used for taxonomical comparison amnog species. Therefore, the spine structure variation within areoles and individuals of one population of Gymnocalycium kieslingii subsp. castaneum (Ferrari) Slaba was analyzed. Fifteen plants were selected and from each plant one areole from the basal, middle and upper part of the plant body was sampled. A scanning electron microscopy was used for spine surface description and a light microscopy for measurements of spine width, thickness, cross-section area, fiber diameter and fiber cell wall thickness. The spine surface was more visible and damaged less in the upper part of the plant body than in the basal part. Large spine and fiber differences were found between upper and lower parts of the plant body, but also within single areoles. In general, the examined traits in the upper part had by 8–17% higher values than in the lower parts. The variation of spine and fiber traits within areoles was lower than the differences between individuals. The minimum sample size was largely influenced by the studied spine and fiber traits, ranging from 1 to 70 spines. The results provide pioneer information useful in spine sample collection in the field for taxonomical, biomechanical and structural studies. Nevertheless, similar studies should be carried out for other cacti species to make generalizations. The large spine and fiber variation within areoles observed in our study indicates a very complex spine morphogenesis.

Leaf morphological characters are important, especially for plant identification and classification. Leaf morphological characters are mainly used for classifying a particular genus, species and varieties, but leaf architectural patterns are not much studied. This study has been undertaken for identification of 30 Mangifera indica L. varieties based on venation characteristics. The results showed that pinnate type are common in the Kaju, Totapuri and Badshahpasand varieties, which are usually characterized by thick primary veins. Secondary veins were of camptodromous type. Minor venation was measured up to five orders and all varieties studies showed fimbriate venation. Other qualitative characters of secondary vein (angle of divergence, course, intersecondary vein), tertiary vein (pattern), higher order venation (course), veinlet branching, areole development, areole arrangement and areole shape were undertaken. Quantitative observations included number of areoles per mm2, average size of areole per mm2,...

Two new species of Lichenothelia, both from Iran, are described. Lichenothelia iranica is characterized by a black thallus with often finely lobate, slightly effigurate, not areolate margins, eight non-amyloid spores per ascus and 1–3-septate ascospores with 1–2 longitudinal or oblique septa. Lichenothelia ilamensis is distinguished by a black areolate, fissured, slightly effigurate or rarely lobulate thallus. The areoles are confluent and aggregated in the centre, becoming dispersed towards the margin, and the asci contain (4–)6(–8) non-amyloid, 1-septate spores.

Age estimation has been a limiting factor in the study of giant columnar cacti. In order to test the feasibility of using radiocarbon methods to estimate the age of the giant cardon cacti (Pachycereus pringlei), we selected six sites spanning the latitudinal and precipitation range of the species in the Baja California peninsula. In each site, we selected four individuals of different heights and sampled a spine from the lowest areole in the stem. The age of the spine was estimated using 14C dating, and the mean annual growth rate of the plant was calculated dividing the height of the lead shoot by the plant’s age. Mean annual growth rate was 0.098 m/yr, with values varying between 0.03 and 0.23 m/yr. Within the range of plants sampled, mean annual growth rates were significantly correlated with the height of the plant (r2=0.82, P14C dating provides a robust method to explore the growth and demography of columnar cacti.

The hooded pitcher plant, Sarracenia minor, is a carnivorous facultative wetland species native to the southeastern USA and is listed as threatened by the state of Florida. Pitchers of S. minor possess white, semitranslucent spots (areoles), which have been hypothesized to aid in the capture of prey (= visual lures) by increasing the amount of light entering the back of the hood, which persuades insects to enter and fall into the base of the pitcher. In this study, the role of the areoles in prey capture abundance and diversity were experimentally investigated under variable lighting conditions in situ. Plants in two populations experiencing different light intensities, which varied in the amount of canopy cover and incident light reaching the plants, were experimentally manipulated by coloring varying percentages of areoles, ranging from 0 to 100 % (in increments of 25 %), with indelible ink. After 2 months, pitchers were collected and dissected to determine the number and identity of prey captured (approximately 18,000 prey were sampled). Although total prey abundance was approximately five times higher at McGirt’s Creek (sunny site) compared to UNF (shaded site), the effect of areoles on prey capture rates and biodiversity was site dependent. Reducing the number of visual lures of plants at the sunny site produced a significant decrease in the number of prey captured, but prey biodiversity (community composition) was unaffected. However, total prey capture was unaffected at the shaded site, while prey biodiversity was negatively correlated with the percent of areoles colored. Results from the current study suggest that areoles conditionally act as visual lures, but their overall importance is dependent on local environmental variables—especially canopy cover and the amount of incident sunlight reaching the plants.

Bark coverage occurs on stems of more than twenty species of columnar cacti. This report documents characteristics of areoles and spines from central Mexico with bark coverage percentages on five columnar cactus species (Cephalocereus columna-trajani, Neobuxbaumia macrocephala, N. mezcalaensis, N. tetetzo, and Pachycereus hollianus). Older cacti (more than 4 m tall) had fewer original spines than younger cacti (less than 2 m tall). For cacti taller than 4 m, loss of the original spines was positively correlated with bark coverage. For three species, loss of the original spines occurred with about 75% for bark coverages. Four of the five species studied produced hair-like spines at areoles. Three of the five species produced emergent spines. Most emergent spines were associated with hair-like spines. The presence of hair-like and emergent spines (spines that emerged on mature cactus surfaces) was not well correlated with percentages of bark coverage. Hair-like spines have been noted previously, but no function has been attributed to them. This is the first report with a description of emergent spines on tall, long-lived columnar cactus species.

To our knowledge, there are no studies about the structure and ecological function of extrafloral nectaries (EFNs) in Opuntia robusta. This is the first description of EFNs in O. robusta, where young spines have an interesting structure and a secreting function, which are different from EFNs described in other Cactaceae species. We used light, scanning-electron, and transmission-electron microscopy to examine morphology, anatomy, and ultrastructure of the secretory spines in areoles in female and hermaphrodite individuals of O. robusta. Young cladodes develop areoles with modified and secretory spines as EFNs only active during the early growth phase. EFNs are non-vascularized structures, with no stomata, that consist of a basal meristematic tissue, a middle elongation region, and an apical secretory cone formed by large globular epidermal cells, containing nectar and medullar elongated cells. We observed the presence of Golgi apparatus, vesicles and plastids in the medullar and sup-epidermal cells of the spine. We propose that the nectar is stored in the globular cells at the apex of the spine and secreted by breaking through the globular cells or by pores. We recorded a more frequent presence of ants on younger cladode sprouts producing young secreting spines: this result is parallel with the predictions of Optimal Defense Hypothesis, which states that younger plant organs should be better defended than older ones because their loss produces a higher fitness impairment. Although Diaz-Castelazo's hypothesis states that a more complex structure of EFNs correlates with their lower among-organs dispersion, comparing to less complex EFNs, non-vascularized structure of EFNs in O. robusta is not associated with their higher among-organs dispersion likened to O. stricta, which produces vascularized EFNs. We provide evidence that this characteristic is not a good taxonomic feature of Opuntia genus. Moreover, the comparison of EFNs of O. robusta and O. stricta suggests that the hypothesis of Diaz-Castelazo should be revised: it is rather a rule but not a law.

The new subspecies Gymnocalycium sutterianum (Schick) Hosseus subsp. arachnispinum Řepka (Cactaceae, Trichocereeae) is described from Cordoba, Argentina. It differs from the nominate subspecies mainly in the following morphological characters: a smaller plant body, shorter distances between areoles, smaller hemispherical tubercles (8–12 mm in diameter), seven to nine shorter spines (7–10 mm) per areole that are shorter and often bent over the tubercles, thinner spines in cross-section 0.25–0.4 mm in diameter, smaller flowers, and pericarp to perigon ratios from 1:2 to 2:3. The new subspecies also differs in genome size and ploidy level (G. sutterianum subsp. sutterianum 2n = 6x, G. sutterianum subsp. arachnispinum 2n = 4x). Moreover, populations of the new subspecies are found in a separate distribution area from that of the nominate subspecies. The new combination G. sutterianum subsp. dolezalii (Halda & Milt) Řepka [≡ G. poeschlii Neuhuber subsp. dolezalii Halda & Milt] is established and the subspecies name is neotypified. A taxonomic key to identify the three subspecies of G. sutterianum is included.

The morphology and anatomy of the Backebergia militaris cephalium is characterized in comparison with its vegetative branch and with apical and lateral cephalia of other species. Our working hypothesis was that the B. militaris cephalium is more similar to the apical or lateral cephalia of other taxa than to its own vegetative branch. Our results revealed that the differences between the vegetative branch and the cephalium are primarily morphological: there is a change in the phyllotaxy, there are no interareolar spaces, making the ribs indistinguishable and abundant trichomes and bristles are produced in the areoles. In addition, a comparison between the vegetative branch and the cephalium shows differences in the epidermal cell size, thickness of the hypodermis and abundance of cortical bundles and mucilage cells. Unlike Melocactus intortus apical cephalia, B. militaris retains stomata in the epidermis and chlorenchyma, allowing the cephalium near the apical meristem to perform photosynthesis. The development of periderm in each areole after flowering and fruiting is a distinctive and defining feature of lateral and apical cephalia. In addition to early periderm development, the necrosis of cortical and pith parenchyma and fibers in secondary xylem and phloem in B. militaris distinguishes it from other cephalia described to date.

A new species from Ecuador, Symplocos limonensis, is here described and illustrated. It resembles Symplocos clethrifolia but differs by having larger leaves with evident (i.e., not concealed) areoles on lower surface, sessile inflorescences, smaller white corollas, and fewer stamens. The species is only known from three collections in the Andean forests of Morona-Santiago Province in southern Ecuador.ResumenSe describe e ilustra una nueva especie