26/07/2020
°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°
Caper White Butterfly in lockdown survey in our garden at Shyamnagar
ππππππππππππππππππππππππππππππππππ
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Beautiful design observed on natural wings
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sofistication & delicacy is the art of nature ;
Zebra tip Caper White Butterfly (Belenois aurota) while visited our garden ("Dhirendra Shnrhalaya" at Shyamnagar, North 24 Parganas, Latitude: 22° 49' 59.99" N &Longitude: 88° 22' 0.01" E) observed with Nikon d5600 through 70-300 Zoom Photographic Gear snapped just now on July,26,2K20.
Belenois aurota is a small- to medium-sized butterfly species of the whites-and-yellows family Pieridae. The butterfly is recognizable by its white color with small black dots on its wings, and it can be distinguished from P. brassicae by the smaller size and lack of the black band at the tip of their forewings.
Scientific classification
~~~~~~~~~~~~~~~
Kingdom : Animalia
Phylum : Arthropoda
Class : Insecta
Order : Lepidoptera
Family : Pieridae
Genus : Belenois
Species : B.aurota
Binomial name : Belenois aurota
Described by : (Fabricius, 1793)
Synonyms
~~~~~~~
Papilio aurota Fabricius, 1793
Anaphaeis aurota
Papilio mesentina Cramer, 1780
Papilio augusta Olivier, 1807
Pinacopteryx syrinx Wallengren, 1860
Pieris lordaca Walker, 1870
Belenois auriginea Butler, 1886
Pieris mesentina ab. iris Gauckler, 1912
Pieris mesentina ab. sulphurea Gauckler, 1912
Pieris mesentina f. pusillima Strand, 1915
Pieris mesentina ab. punctifera Hulstaert, 1924
Wide distribution of Little white Butterfly
~~~~~~~~~~~~~~~~~~~~~~~~~~
The species has a natural range across Europe, Asia, and North Africa. Estimates show that a single female of this species might be the progenitor in a few generations of millions.
It is absent or scarce in desert and semidesert regions (except for irrigated areas). It does not seem to have made it to South America.9
The species can be found in any open area with diverse plant association. It can be seen usually in towns, but also in natural habitats, mostly in valley bottoms. Although an affinity towards open areas is shown, the small white is found to have entered even small forest clearings in recent years.
Description
~~~~~~~~
In appearance it looks like a smaller version of the large white The nominate subspecies B. aurota is found in Europe, while Asian populations are placed in some other subspecies along with this one. Other subspecies include atomaria, eumorpha, leucosoma, mauretanica, napi, novangliae, and orientalis.
The upperside is creamy white with black tips on the forewings. Females also have two black spots in the center of the forewings.
Its underwings are yellowish with black speckles. It is sometimes mistaken for a moth due to its plain appearance. The wingspan of adults is roughly 32–47 mm (1.3–1.9 in).
Due to the environmental condition, backgrown greenaries and nutritional variations they display little difference in their wing colors also !
Life cycle
~~~~~~
The small white will readily lay eggs on both cultivated and wild members of the cabbage family, such as charlock and hedge mustard . B. aurota is known to lay eggs singularly on the host plant. The egg is characterized by a yellowish color and 12 longitudinal ridges.
The egg production peaks about a week after adulthood in lab and the female can live up to 3 weeks. Females tend to lay fewer eggs on plants in clumps than on isolated plants.
It has been suggested that isothiocyanate compounds in the family Brassicaceae may have been evolved to reduce herbivory by caterpillars of the small white. However, this suggestion is not generally accepted because the small white has later been shown to be immune to the isothiocyanate forming reaction due to a specific biochemical adaptation. In contrast, the small white and relatives seem to have evolved as a consequence of this biochemical adaptation to the isothiocyanate- forming glucosinolates.
Traditionally known in the United States as the imported cabbage worm, now more commonly the cabbage white, the caterpillars are bluish-green, with tiny black pints, a black ring around the spiracles, and a lateral row of yellow dashes, and a yellow middorsal line. Caterpillars rest on the undersides of the leaves, making them less visible to predators. Although the larval instars have not been fully studied, different instars are easily differentiated simply by comparing sizes, especially the head alone.
During the first and second instar the head is entirely black; third instar has the clypeus yellow but the rest of the head black. In the fourth and fifth instar, there is a dark greenish-yellow dot behind each eye but with rest of the head black. However, the color of the caterpillar head does not necessarily indicate specific instar, as the time of color change is not fixed. In the larval stage, the small white can be a pest on cultivated cabbages, kale, radish, broccoli, and horseradish. The larva is considered a serious pest for commercial growth of cabbage and other Brassicaceae.
The caterpillar of this species, often referred to as the "imported cabbageworm", is a pest to crucifer crops such as cabbage, kale, bok choy and broccoli.
The pupa of B. aurota is very similar to that of P. napi. It is brown to mottled-gray or yellowish, matching the background color. It has a large head cone, with a vertical abdomen and flared subdorsal ridge. The two (pupa of B. aurota and P. napi) can be easily distinguished by comparing the proboscis sheath. In B. aurota, the proboscis sheath extends far beyond the antennal sheath while in P. napi, only a very short distance.
Belenois aurota is widespread in Europe and Asia; it is believed to have originated in the Eastern Mediterranean region of Europe, and to have spread across Eurasia thanks to the diversification of brassicaceous crops and the development of human trade routes. Over the past two centuries, it has also spread to North Africa, North America, New Zealand, and Australia, as a result of accidental introductions.
Larva feeding
~~~~~~~~~
The Belenois aurota larva is voracious. Once it hatches from the egg, it eats its own eggshell and then moves to eat the leaves of the host plant. It bores into the interior of the cabbage, feeding on the new sprouts. The mustard oil from the host plant makes the larva distasteful to birds. The larvae adjust their feeding rate to maintain a constant rate of nitrogen uptake. They will feed faster in low nitrogen environment and utilize the nitrogen more efficiently (at the cost of efficiency in other nutrients) than larvae hatched on nitrogen high host plant. However, no significant difference in growth rate was observed between larvae in the two environments.Considered a serious pest, the caterpillar is known to be responsible for annual damage worth hundreds of thousands of dollars.
The larvae are shown to disperse their damage on the plant. Larvae are shown to feed mostly during the day. They move around the plant mostly spending their time feeding. A feeding bout is immediately followed by a change in position, either to a new leaf or to another part of the same leaf. This dispersal of damage is seen as an adaptive behavior to hide the visual cues from predators that rely on vision. Even though Belenois aurota larvae are cryptic, they remain in the sun for the majority of the day, rather than hiding on the underside of the leaf. The condition of the host plant influences the larval growth significantly.
Adult feeding
~~~~~~~~~
Adult B. aurota use both visual and olfactory cues to identify flowers in their foraging flight. The cabbage butterfly prefers purple, blue and yellow flowers over other floral colors. Some flowers, like Brassica rapa, have a UV guide for aiding nectar search for the butterfly where the petals reflect near UV light whereas the center of the flower absorbs UV light, creating a visible dark center in the flower when seen in UV condition. This UV guide plays a significant role in B. aurota foraging.
Reproduction
~~~~~~~~~
The male, when it spots a female, zigzags up, down, below, and in front of her, flying until she lands. The male flutters, catches her closed forewings with his legs, and spreads his wings. This causes her to lean over. He usually flies a short distance with her dangling beneath him. An unreceptive female may fly vertically or spread her wings and raise the abdomen to reject the male. Most host plants of P. rapae contain mustard oils and females use these oils to locate the plants. Females then lay the eggs singly on host leaves. In the northern hemisphere, adults appear as early as March and they continue to brood well into October. Spring adults have smaller black spots on its wings and are generally smaller than summer adults.
Host selection
~~~~~~~~~~
There are three phases to host selection by the B. aurota adult female butterfly: searching, landing, and contact evaluation. A gravid female adult will first locate suitable habitats, and then identify patches of vegetation that contain potential host plants. The cabbage butterflies seem to limit their search to open areas and avoid cool, shaded woodlands even when host plants are available in these areas. Furthermore, gravid females will not oviposit during overcast or rainy weather. In laboratory conditions, high light intensity is required to promote oviposition.
All known host plants contain natural chemicals called glucosinolates, that are cues for egg laying. Host plants are: herb Cruciferae – Arabis glabra, Armoracia lapthifolia, Armoracia aquatica, Barbarea vulgaris, Barbarea orthoceras, Barbarea verna, Brassica oleracea, Brassica rapa, Brassica caulorapa, Brassica napus, Brassica juncea, Brassica hirta, Brassica nigra, Brassica tula, Cardaria draba, Capsella bursa-pastoris (females oviposit but larvae refuse it), Dentaria diphylla, Descurainia Sophia, Eruca sativa, Erysimum perenne, Lobularia maritima, Lunaria annua (retards larval growth), Matthiola incana, Nasturtium officinale, Raphanus sativus, Raphanus raphanistrum, Rorippa curvisiliqua, Rorippa islandica, Sisymbrium irio, Sisymbrium altissimum, Sisymbrium officinale (and var. leicocarpum), Streptanthus tortuosus, Thlaspi arvense (larvae grow slowly or refuse it); Capparidaceae: Cleome serrulata, Capparis sandwichiana; Tropaeolaceae: Tropaeolum majus; Resedaceae: Reseda odorata.
Egg-laying behavior
~~~~~~~~~~~~~
A gravid female adult will lay disproportionate number of eggs on peripheral or isolated plants. A single larva is less likely to exhaust the whole plant, therefore laying eggs singly prevents the likelihood of larval starvation from resource exhaustion. This behavior may have evolved to exploit the original vegetation in the eastern Mediterranean where brassica plants originated.
Predation
~~~~~~~
Unlike the large white, they are not distasteful to predators like birds. Like many other "white" butterflies, they overwinter as a pupa. Bird predation is usually evident only in late-instar larvae or on overwintering pupae.
Bird predators include the house sparrow (Passer domesticus), goldfinch (Carduelis carduelis) and skylark (Alauda arvensis). Caterpillars are cryptic, coloured as green as the host plant leaves and they rest on the undersides of the leaves, thus making them less visible to predators.
Parasitism
~~~~~~~~
B. aurota caterpillars are commonly parasitized by a variety of insects. The four main parasitoids are Cotesia rubecula, Cotesia glomerata, Phryxe vulgaris, and Epicampocera succinata. Cotesia rubecula and Cotesia glomerata, previously in the genus Apanteles, were introduced in North America from Asia as biocontrols. C. rubecula lays its eggs in the 1st and 2nd instar caterpillars. The larvae then grow within the caterpillar and continue to feed on the caterpillar until they are almost fully grown, and at that point the caterpillar is killed. It is important to note that only one larva develops per host and the rate of C. rubecula is largely independent of B. aurota population size, C. glomerata is similar to C. rubecula in that both parasitize the host in either the 1st or 2nd instar. The main difference is that C. glomerata always kill the host in the 5th instar and multiple larvae can be raised within one host.
