Xylocopa Latipes Research Articles

Floral Visitors of the Golden Rain Tree, Cassia fistula (Fabaceae), in Campeche, Mexico1

Abstract Cassia fistula L., known as the golden rain tree, is a flowering tree that is native to Asia but is used as an ornamental plant in public and private gardens in many areas of Mexico. It is also important for its antifungal, antibacterial, antioxidant, phytochemical, and medicinal properties. In this study, floral visitors of C. fistula were identified in the urban area of Escarcega, Campeche, Mexico in three public gardens during the month of May using entomologic nets. The insects were preserved with 70% alcohol, transported to the laboratory, and identified to species level using taxonomic keys. In total, 124 insects were collected representing 8 species belonging to 7 genera. Of those insects collected, Trigona fulviventris Guérin-Méneville and Trigona silvestriana Vachal (Hymenoptera: Apidae) were the most abundant, accounting for almost 50% of the total specimens collected. Previous reports list 32 species of insects as floral visitors of C. fistula in Mexico. Our study adds six species to that list that had not been previously recorded: Epicharis elegans Smith, Eulaema polychroma (Mocsáry), Melipona sp., T. silvestriana, and Xylocopa latipes (Drury), which are all members of the family Apidae (order Hymenoptera), and Parachartergus apicalis (F.), a vespid (Hymenoptera: Vespidae).

The mechanical fit of the flowers of Crotalaria paniculata Willd. for the pollination success of large-bodied bees

The present study investigates the morphology of floral parts adapted towards the mode of pollination by bees in a lesser-known shrub, Crotalaria paniculata Willd of the family Fabaceae. The morphology and orientation of flowers, colour, shape, size and number of each floral part were recorded. The floral odour was assessed qualitatively at various stages of flowers manually and the quantity of nectar produced per flower was also measured. The flowering individuals were regularly monitored to observe the floral visitors and their foraging activity on a series of aged flowers. The performance of each floral visitors like visitation frequency, handling time, relative abundance, activity rate, visitation rate index and visitor activity index was calculated. The flowers of C. paniculata are typical papilionaceous and keel-blossom types that function as floral advertisement and nectar and pollen grains are served as floral rewards. The standard petal serves an advertisement whereas the wing-keel complex acts as a landing platform for floral visitors. The large-bodied bees tend to break the wing-keel complex which facilitates cross-pollination. Xylocopa latipes (Apidae) was observed as the most effective pollinator due to their higher frequency of visits, activity rate, visitation rate index and visitor activity index. Due to the pressure applied by large-bodied bees like Xylocopa latipes by landing on the wing-keel complex, the reproductive parts become exposed and the stigma brushes the pollen load in the body of the visitors and effect cross-pollination. The study concludes that large-bodied bees are effective floral visitors of C. paniculata which effect cross-pollination.

The effects of meliponicultural use of Tetragonula laeviceps on other bee pollinators and pollination efficacy of lemon.

The augmentation of pollination success in lemon (Citrus limon Eureka) flowers remains contingent on the involvement of bee pollinators. With wild bee pollinator populations declining in agroecosystems, meliponiculture has emerged as a potential option in Indonesia. This study aimed to investigate the effects of meliponicultural use of Tetragonula laeviceps on diversity, foraging behavior, and monthly population of bee pollinators, as well as lemon pollination efficacy with and without meliponiculture treatment during two periods. Using scan and focal sampling methods in first and second periods, the study found that the diversity of wild bee pollinators was six species (Apis cerana, Lasioglossum albescens, Megachile laticeps, Xylocopa confusa, Xylocopa latipes, and Xylocopa caerulea), and T. laeviceps when using meliponiculture. The relative abundance and daily foraging activity of wild bee pollinators were initially reduced in the first period (March-June) and then maintained in the second period (July-October). T. laeviceps foraged on the flowers, involving specific sequences for 72 s with highest visitation rate of 0.25 flowers/h from 10:00-13:00. Light intensity was observed to be the most influential factor for bee pollinator density. Pollination efficacy results showed that meliponiculture usage has greater benefit compared to meliponiculture absence across various parameters, including fruit sets, fruit weight, yield, and estimated productivity. The effects of meliponicultural use of T. laeviceps can enhance lemon pollination efficacy while preserving the diversity of wild insect pollinators. This suggests that meliponiculture stingless bees could be a beneficial practice in agroecosystems, especially in tropical regions where wild bee populations and diversity are declining.

Effects of meliponiculture Tetragonula laeviceps on pollinator diversity and visitation rate and citrus productivity in West Java, Indonesia

Abstract. Nurdiansyah MA, Abduh MY, Permana AD. 2023. Effects of meliponiculture Tetragonula laeviceps on pollinator diversity and visitation rate and citrus productivity in West Java, Indonesia. Biodiversitas 24: 5757-5763. Citrus reticulata var. Rimau Gerga Lebong (RGL) is a prominent Indonesian citrus variety, yet its global productivity is facing challenges due to decreasing diversity in pollinators. This study aimed to bolster the productivity of C. reticulata var. RGL in Bandung by introducing Tetragonula laeviceps Smith 1857 (Hymenoptera: Apidae). Simultaneously, the study explored the influence of pollinator diversity, foraging behavior, and visitation rates and compared the results with open and wind pollination. Field investigations were conducted to observe the pollination activities of T. laeviceps and eight wild pollinator species, including Apis cerana Fabricius 1793, Ceratina cognata Smith 1879, Xylocopa confusa Pérez 1901, Xylocopa latipes Drury 1773, Vespa affinis Linnaeus 1764, Dolichoderus thoracicus Smith 1860, Papilio demoleus Linnaeus 1758, and Catopsilia pyrantel Linnaeus 1758. T. laeviceps exhibited the highest relative abundance (34.87%) and an average time spent of 72.11 seconds per flower. Visitation rates were highest during noon (10:00 to 13:00) at 0.31 pollinators/hour/flower, influenced by temperature, relative humidity, and light intensity. The phenological stages of C. reticulata var. RGL spanned 240 days. Fruit set, fruit weight, and estimated citrus productivity were significantly higher in T. laeviceps and open pollination compared to wind pollination. This study highlights the suitability of T. laeviceps as an effective pollinator for C. reticulata var. RGL. The findings have implications for the conservation and management of pollinator populations to ensure sustainable citrus production in the declining global diversity.

Visiting of Carpenter Bees Xylocopa latipes Drury to The Bean Crop in Central Sulawesi

Xylocopa latipes Drury are one species of bee found in the Hymenoptera order, in the family Anthophoridae. Carpenter bees, which are essential for plant pollination, build their nests in decaying wood and bark. Carpenter bees visit the bean crop to collect pollen and nectar for their hives. This study aims to determine the visit of the wood bee X. latipes on long bean plants in Central Sulawesi. The study employed a descriptive survey methodology that involved field sampling at bean planting and direct observation of X. latipes in the field. measured the temperature and the light intensity. The findings revealed that X. latipes visits to the bean crop at Desa Nambaru, Kecamatan Parigi Selatan, Kabupaten Parigi Moutong average 58,3 people each visit. The morning at 08.30 am averages 21 X. latipes visits; the afternoon at 15.30 pm averages 9 Xylocopa latipe visits; and the afternoon at 11.30 am averages 2 Xylocopa latipe visits. The amount of light present during X. latipes visit to the bean crop has a significant impact. Weather variables like temperature, humidity, and wind speed had an impact on the multivariate regression's very real relationship to X. latipes visit to bean planting.

Pollination biology of yellow passion fruit (Passiflora edulis forma flavicarpa) at typical Indonesian small-scale farming

Abstract. Putra RE, Wibisana G, Kinasih I, Raffiudin R, Soesilohadi RCH, Purnobasuki H. 2023. Pollination biology of yellow passion fruit (Passiflora edulis forma flavicarpa) at typical Indonesian small-scale farming. Biodiversitas 24: 2179-2188. Yellow passion fruit (Passiflora edulis forma flavicarpa) has been considered one of the potential local fruits targeted as the export commodity of Indonesia. However, this fruit production level is relatively unstable, which lowers their potency as cash crops and makes them secondary fruits for small-scale farmers. One of the possible factors related to this condition is pollination success. This research aimed to study the pollination biology of yellow passion fruit in terms of flower interaction with insects and the morphological aspect of flowers. The observation was conducted in four sites at Kampung Organik Beji, Wonogiri Regency, between January-February 2022. Pollinators' census was done by scan sampling while flower-visiting insect activities were monitored by focal sampling. This study found 26 species of flower-visiting insects which can be grouped into 5 Ordo and 12 Families with moderate diversity index (H’=2.15), evenly distributed (J’=0.66), and low domination (D=0.32). Among identified insects, carpenter bees (Xylocopa latipes), stingless bees (Tetragonula laeviceps), and Asiatic honey bees (Apis cerana) were considered as pollinators in which X. latipes (Vt=11.81±7.44 second, Fvr=2.41±1.55) visited flower (Vt) on shorter times, and more flower visitation rate (Fvr) than T. laeviceps (Vt=12.36±8.32 second, Fvr=1.10±0.30). Furthermore, this study found that the benefit of natural pollination was better than hand cross-pollination. However, the benefit was hampered by a lack of plant protection and soil fertility management. This study may be applied as baseline information to create pollinator protection zones in the area near the plantation zone to ensure the pollination services for crops.

Polarized iridescence of the tropical carpenter bee, Xylocopa latipes

The tropical carpenter bee, Xylocopa latipes, has metallic-reflecting, iridescent wings. The wing reflectance spectra for TE- and TM-polarized light depend on the angle of light incidence in a way characteristic for dielectric multilayers. Anatomy indicates the presence of melanin multilayers in the wing’s chitinous matrix. A simple optical model of melanin multilayers explains the angle dependence of the wing reflectance spectra. The wing reflections that occur upon oblique illumination exhibit colourful and strongly polarized light patterns, which may mediate intraspecific signaling and mutual recognition by conspecifics.

Morphometrics Variations of Carpenter Bees Xylocopa confusa Latreille and Xylocopa latipes Drury from Different Habitats in Central Sulawesi

Habitat is a place for living things to grow and develop. Differences in physical characteristics of habitats within an area can affect the morphometry of an organism. This study aims to provide information related to the morphometric variation of the carpenter bees Xylocopa confusa Latreille and Xylocopa latipes Drury in different habitats in Central Sulawesi. The research was conducted in four types of habitat, namely primary forest, secondary forest, rural areas, and urban areas in January 2019. The collection of carpenter bees useds a sweep net by swinging it around the sampling location. The carpenter bees obtained were then killed in a killing jar for five minutes. The carpenter bees samples were put into a sample bottle based on the type of habitat. Furthermore, the pinning process was carried out using insect needles. The results showed that the physical characteristics of the different habitats could affect the morphometric variations of the carpenter bees Xylocopa confusa and Xylocopa latipes. The size of the body morphometry of carpenter bees is larger in primary forest habitats, while the smallest size of bees is found in urban areas. This research is useful as preliminary data before carrying out the cultivation and conservation process of wood bees considering that their role in nature is very important.

Species diversity and distribution of wild bees (Hymenoptera: Apoidea) in Binh Chanh District, Ho Chi Minh City

As the most significant pollinators of wild plants, bees play an important role in sustaining the natural ecosystems. In this study, we conducted surveys of bee fauna of three different habitat types during dry and rainy seasons of 2020 in Binh Chanh District, Ho Chi Minh City. A total of 169 individuals from 13 bee species belonging to six genera were collected. Of these, eight species are newly recorded from Ho Chi Minh City: Amegilla calceifera, A. himalajensis, A. zonata, Ceratina nigrolateralis, C. smaragdula, Xylocopa aestuan, X. latipes, Tetragonula fuscobalteata. The species composition of bees was more diverse in forest habitat than rural garden and canalbank habitats. The richness and abundance of bees were significantly higher in the dry season than the rainy season. Apis florea was abundant in forest and rural garden habitats while Ceratina smaragdula occurred plentifully in the canalbank habitat. Eight bee species (Apis cerana, A. dorsata, A. florea, Thyreus himalayensis, Xylocopa latipes, X. aestuans, Ceratina smaragdula, and C. nigrolateralis) widely distributed throughout all three habitats. By contrast, four bee species (Amegilla calceifera, A. himalajensis, Apis mellifera, and Tetragonula fuscobalteata) exclusively appeared in the forest habitat.

Effect of Different Insecticides on Yield, Yield Attributes and Pollinator Behaviour of Different Pigeon Pea Varieties

Background: Yield of pigeon pea, besides other management practices, highly relies on variety and pollinators. Again, different insecticides are also known to immensely influence the abundance of these pollinators. Hence, the current study was conducted with objectives to record diversity of flower visitors and abundance of insect pollinators, to work out pollination efficiency of major pollinators and to evaluate the effect of different varieties and insecticidal treatments on the pollinator behaviour, yield and yield attributes of pigeon pea in order to reduce the ecological impact of chemicals as well as to increase the productivity of pigeon pea. Methods: The experiment was designed in a Split plot arrangement replicated thrice. The varieties were assigned in main plots and had four levels such as UPAS-120, PA-406, PA-421 and PA-441. Types of insecticides applied were taken in the sub plots and it also had four levels viz. Quinalphos 25 EC (325 g a.i./ha), Lufenuron 5.4 EC (30 g a.i./ha), Deltamethrin 2.8 EC (12.5 g a.i./ha) and Indoxacarb 15.8 EC (50 g a.i./ha). Result: Outcomes emanated from the study revealed that Megachile disjuncta, Xylocopa latipes and Megachile bicolor were the three most important pollinator bee species on kharif pigeon pea in the tarai region of Uttarakhand. Among the varieties, UPAS-120 and PA-441 had better cross pollination potential over the PA-406 and PA-421. Insecticides had overall negative impact on the insect pollinators. However, Deltamethrin 2.8 EC at recommended dose was found to have least impact on the insect pollinators. Quinalphos 25 EC and Lufenuron 5.4 EC were observed to be more deleterious on pollinators. The ultimate impact on the pollinator insects were profound on the yield and yield attributes of pigeon pea.

Bacterial Communities in Three Parts of Intestinal Tracts of Carpenter Bees (Xylocopa tenuiscapa).

This study investigated different bacterial communities in three intestinal parts (foregut, midgut and hindgut) of Xylocopa tenuiscapa to understand the roles of gut bacteria. Our phylogenetic analysis revealed that X. tenuiscapa is closely related to Xylocopa latipes. The 16S rRNA gene in the genomic DNA samples from the gut was examined by illumina (Solexa) and a total of 998 operational taxonomic unit (OTUs) clusters were found. Taxonomic classification identified 16 bacterial phyla and unclassified bacteria. The dominant bacteria taxa in the three parts of X. tenuiscapa gut were Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria. In the foregut, Lactobacillales and Enterobacteriaceae were predominantly found. The population in the midgut was similar to that in the foregut, with the addition of Gilliamella, which was also abundant. The most dominant bacteria identified in the hindgut were similar to those in the midgut and Lactobacillales, Enterobacteriaceae, Gilliamella, Bifidobacteriaceae and Flavobacteriaceae appeared in abundance. Moreover, our results suggest that a community structure of bacteria in different parts of X. tenuiscapa’s gut may be an important indicator of carpenter bees’ health. This functional study of bacterial communities revealed significant differences among the three intestinal parts and is the first report of the gut bacteria structure in solitary bees.

Flower and fruit development and flower-visiting insects of gmelina (Gmelina arborea roxb.)

The purpose of the research was to identify flower development and fruit formation as well as identification of flower-visiting insects as potential pollinators. Observations carried out in three sample trees, and five flowering branches at each sample tree were marked. We also carried out the identification of flower-visiting insects, foraging behavior, visiting rate, number of visiting insects, and time of flower visit. The results showed that in one year, 2-3 reproductive cycles might occur, which one cycle lasted about 1-2 months. In a panicle of flowers, flower buds, flower bursts and fruitlets are found simultaneously. The panicle has 5-34 flower buds. The development of buds to panicle formation takes 5-7 days, while the time required for flower and fruit development from generative buds up to yellow fruit was in a range between 38 to 67 days or 1 to 2 months. The total reproductive success of sample trees was varying from 12% to 17%. The most dominant flowers-visiting insects and alleged as pollinators of G. arborea is a carpenter bee (Xylocopa latipes) that actively visiting flowers at 8:00 until 11:00 am. Insect visited about 5 to 20 flower panicles with an average of 11 flower panicles per minute.

The bees (Apocrita: Hymenoptera) of Dhaka city, Bangladesh

A total of 11 bee species belonging to two families Apidae and Megachilidae was identified. The identified species were Apis dorsata, Apis mellifera, Apis cerana, Apis florea, Ceratina binghami, Ceratina nigrolateralis, Xylocopa aestuans, Xylocopa violacea, Xylocopa latipes, Megachile disjuncta and Megachile umbripennis. The species were identified by using standard taxonomic keys. Details of external morphology like head, wing venation, antennal type, physical coloration etc. were used in the keys. The bees were collected from three areas of Dhaka city - Curzon Hall, Ramna Park and Sher-e-Bangla Agricultural University from October 2017 to May 2018. During the study period it was observed that the richness of bee species was found maximum during the month of October (31.01%) and was more abundant in Curzon Hall and Sher-e-Bangla Agricultural University area than the Ramna park area. The bee A. dorsata was the most abundant (about 36.23% of the total population) and M. umbripennis was the least abundant (about 1.74% of the total population) species in the study areas. It was also observed that bee species were more attracted to the yellow flowers specially Cosmos sulphureus and Tecoma stans than the other coloured flowers.
 J. Biodivers. Conserv. Bioresour. Manag. 2019, 5(1): 113-120

Nectar robbing in bellflower (Sesamum radiatum) benefited pollinators but unaffected maternal function of plant reproduction

Nectar robbing – foraging nectar illegitimately – has negative, neutral, or positive effects on maternal function of plant reproduction and/or on pollinators. It has been suggested that nectar robbing has a non-negative effect on maternal function of plant reproduction in autogamous and mixed breeding plants; however this hypothesis requires deeper understanding with more studies. We investigated the impact of natural nectar robbing on maternal function of plant reproduction and visitation characteristics of pollinators in Sesamum radiatum, an autogamous plant. Pollinators were observed on unrobbed open flowers and robbed open flowers. In robbed flowers, pollinators’ visit type and foraging time were examined. The seed sets of these flower types were examined. Xylocopa latipes was both a primary robber and a legitimate pollinator, X. bryorum was an exclusive primary robber, and Megachile disjuncta was a cosmopolitan pollinator. In robbed flowers, most of the pollinators foraged mostly as secondary nectar robbers. The foraging time shortened considerably when pollinators robbed nectar – a positive effect on pollinators’ foraging efficiency. Robbing did not negatively affect seed set – a neutral effect on the plant’s reproduction. Our study agrees that nectar robbing might have a non-negative effect on reproduction in autogamous and mixed breeding plants.

Studies on diversity, abundance and pollination efficiency of insect pollinators and pollination mechanism involved in sun hemp (crotalaria juncea.l.)

Biodiversity of insect pollinator's species visiting sunnhemp crop was studied in TNAU Coimbatore, India. Fifteen insect species belonging to four orders were recorded from sunnhemp flowers, of which nine belongs to order Hymenoptera, two to Lepidoptera, two to Coleoptera and one to Diptera. Among the different insect pollinators Xylocopa latipes, Xylocopa pubescens and Megachile lanata are the most frequent visitors. These are also capable of impeding pollination in sunnhemp flowers. Among different bee species maximum mean population was observed in Megachile lanata-4.72 bees/M2/5 minutes followed by Xylocopa latipes 3.65 bees/M2/5 minutes and lowest abundance was observed in case of Xylocopa pubescens (3.215 bees/M2/5 minutes). The pollination index of Xylocopa latipes (7.05) was highestfollowed by Xylocopa pubescens (6.85)and Megachile lanata (6.84). Hence it is concluded that Xylocopa latipes was the most efficient pollinator of sunnhemp flower. The seed for this potentially valuable green manure crop is largely unavailable due to paucity of pollinators and self-incompatible nature of the plant. These pollinators are able to overcome the floral barriers in sunnhemp flowers. Compared to male bees, the females are more efficient in pollinating, the male bees collect only nectar while female bees collect both nectar and pollen for the purpose of reproduction and feeding the offspring’-s.

Keanekaragaman, perilaku kunjungan, dan efektivitas serangga penyerbuk pada tanaman mentimun (Cucumis sativus Linn.)

Cucumber is a monoceous plant and require pollinators for pollination process. Diversity and foraging activity of pollinators affect the effectiveness of pollination, which can improve the yields. The aim of this research were to study the diversity, foraging behavior, and effectiveness of insect pollinators on cucumber plants. Scan sampling was used as on of the methodology for observing pollinator diversity, while foraging behavior was observed using focal sampling. Pollination effectiveness were measured based on the number of fruit set of opened and caged plants. Fifteen species were found as pollinator of cucumber, i.e., Xylocopa confusa Perez, Xylocopa latipes (Drury), Xylocopa caerulea Fabricius, Ceratina bryanti Cockerell, Amegilla burnensis Lieftinck, Nomia quadridentata Bingham, Nomia sp., Megachile unbripennis Smith, Megachile aff. disjuncta Fabricius, Megachile conjuncta Smith, Campsomeris javana Lepeletier, Syrphus sp., Parasyrphus sp., Eurema hecabe Linnaeus, and Vanessa cardui Linnaeus. The longest visit on cucumber flower pattern was by Syrphus sp. (50.71 seconds/flower), while the shortest visit was by X. confusa (4.78 seconds/flower). Pollination by insects increase 100% production as measured by healthy fruit per plant. Pollination also increase 77.61% of seeds number per fruit and 28.57% of seed weight.

DIVERSITY OF Vanda tricolor Lindl. (ORCHIDACEAE) FLOWER-VISITING INSECTS IN THE TURGO HILL OF MOUNT MERAPI NATIONAL PARK, YOGYAKARTA, INDONESIA

<p>Vanda tricolor is an orchid species native to the Mount Merapi National Park, Yogyakarta, Indonesia. The study of interaction flower-visiting insect is important to support in situ conservation program. The purpose of this research wasto study the diversity of Vanda tricolor Lind. flower-visiting insects and their roles in The Turgo Hill of Mount Merapi National Park. Flower-visiting insect was captured in the morning (08.00-10.00 AM), daytime (00.00-02.00 PM) and afternoon (04.00-06.00 PM). Data were taken four times in November 2011 during the flowering season. Insect samples were preserved by dried and wet phase. Sample identification was done in the Entomology Laboratory, Faculty of Biology, Universitas Gadjah Mada. The results indicated that Vanda tricolor flowers were visited by insects from three orders, six families, and eleven species in the morning; four orders, six families, and nine species in the daytime; and two orders, three families, and five species in the afternoon with various role. In this research, we also observed pollination activity potential by Xylocopa latipes (Hymenoptera: Apidae). There were 14 V. tricolor flower-visiting insects from four orders and nine families. There were no significant differences between the insect diversity of the morning and daytime, while in the afternoon there was a decline in the diversity of the insects. <br /><strong></strong></p><p><strong>Keywords</strong>: Vanda tricolor, flower-visiting insects, Turgo Hill of Mount Merapi National Park</p>

Pollination biology of Eriolaena hookeriana Wight & Arn. (Sterculiaceae), a rare tree species of Eastern Ghats, India

Eriolaena hookeriana is a rare medium-sized deciduous tree species. The flowering is very brief and occurs during early wet season. The flowers attract certain bees such as Apis dorsata, Halictus sp., Anthophora sp., Xylocopa latipes, and also the wasp, Rhynchium sp. at the study sites. These foragers collect both pollen and nectar during which they contact the stamens and stigma and effect self- or cross-pollination. Nectar depletion by thrips during bud and flower phase and the production of few flowers daily at tree level drive the pollinator insects to visit conspecific plants to gather more forage and in this process they maximize cross-pollination. The hermaphroditic flowers with the stigmatose style beyond the height of stamens and the sticky pollen grains do not facilitate autogamy but promote out-crossing. The study showed that pollinator limitation is responsible for the low fruit set but it is, however, partly compensated by multi-seeded fruits. Bud and anther predation by beetles also affects reproductive success. Explosive fruit dehiscence and anemochory are special characteristics; these events occur during the dry season. The plant is used for various purposes locally and hence the surviving individuals are threatened. The study suggests that the rocky and nutrient-poor soils, the pollinator limitation, bud and anther predation, establishment problems and local uses collectively contribute to the rare occurrence of E. hookeriana in the Eastern Ghats.

Reproductive characteristics of the invasive species Solanum rostratum in different habitats of Xinjiang, China

The invasiveness of alien plants is closely related to their reproductive characteristics. A compari- son of reproductive characteristics of an alien species in different habitats will help to reveal its optimum habitat for invasion and the mechanism of invasion. Furthermore, it will provide a theoretical foundation for planning a reasonable management strategy. Solanum rostratum is a summer annual weed native to the neotropics and the southwestern USA that produces offspring only by sexual reproduction. This species has become established in seven provinces/cities of China, including Xinjiang. We compared reproductive char- acteristics of S. rostratum in oasis, desert grassland and gravel desert habitats in Xinjiang and determined the optimum habitat for its invasion. The results were as follows. (1) Single-flower duration of S. rostratum was between 27 and 47 hours. Daily flowering time and single-flower duration were similar among the three habitats. However, number of flowers per individual differed among habitats (P desert grassland > gravel desert. (2) Halictus quadricinctus, Halictus sp. and Xylocopa latipes were the pollinators

Allometry and resolution of bee eyes (Apoidea)

A sample of compound eyes from 15 species of female pollen foraging bees (apiform Apoidea) was morphometrically analyzed. These species were chosen for size differences, different social organization, and a wide geographic and taxonomic distribution (Apidae, Megachilidae, Andrenidae, Halictidae). The results demonstrate the following characteristics for the typical compound eye in female foraging bees: (1) the vertical diameter of the eye is about twice the horizontal diameter; (2) the eyes of diurnal foragers scale isometrically with body size; (3) the eyes of three species of nocturnal foragers have about 1.8 times the surface area as compared to diurnal foragers of matching size; (4) the number of ommatidia per eye range from about 1000 in Perdita minima to about 16 000 in Xylocopa latipes; and (5) the corresponding mean interommatidial angles range from 4.7 to 1.2°. Body size, rather than species-specific ecological adaptation, is the major (97%) determinant of the number of ommatidia per eye in diurnal, as well as nocturnal foragers. The number of ommatidia per eye, and hence the visual resolution, is proportional to the square root of both body size and eye size across all species studied. The eye parameter (the product of the mean interommatidial angle and the mean lens diameter) increases slightly with decreasing body size. All this is taken as evidence that the features of the bees' visual macro-niche remained largely constant over the roughly 130 million years of their macro-evolution.