Alecton discoidalis
Encyclopedia
Alecton discoidalis is a species
of firefly
in the beetle family Lampyridae, commonly known as the Cuban endemic firefly. The larva
e of this species are predators on both pulmonate and operculate
land snail
s. Alecton discoidalis is the type species
of the genus Alecton.
of firefly endemic to Cuba
and A. discoidalis is the best known of the four species in that genus. It is found in the western half of the country. The type locality was described simply as "the island of Cuba".
reads as follows:
This translates as: Yellow, with the tips of the antennae
and the elytra black, with a yellow border which starts a third of the way along the elytra.
gastropods and to learn more about the natural history of the species. Larvae of A. discoidalis were collected in limestone
regions of Cuba where they were frequently found in the vicinity of snails. Most collections were made at night at which time the larvae could often be detected when they emitted flashes of light. Representatives of several different instar stages were gathered from leaf litter and from on or under rocks. At the same time, snails of a number of species were collected to determine which species would be the preferred prey
for the larvae. The temperature at the time of collection ranged from 26 to 32 °C and the humidity ranged from 64 to 86%. These levels were maintained in the laboratory during research.
The most vulnerable snails seemed to be those that live on the ground or rocks, but tree-dwelling species were also targeted occasionally. Acceptable prey species included snails from several families: family Helicinidae
(Helicina aspersa
, Ustronia sloanei
, Alcadia hispida
, Emoda sagraiana
), family Pomatiidae
(Chondropoma pictum
, Chondropoma auberianum
, Chondropoma irradians
, Eutudora jimenoi
, Torrella immersa
, Rhytidopoma coronatum
), family Megalomastomatidae
(Farcimen tortum
), family Oleacinidae
(Oleacina
sp.) and family Polygyridae
(Praticolella griseola
).
Snails that were rejected by these larvae as food included Pycnoptychia
species and Liguus fasciatus
.
It was found that attacks took place both during the day and at night with the operculum
of the snail being targeted. The larva spent up to 24 hours inside the shell devouring the soft tissues. Sometimes several first-instar
larvae attacked a single snail at the same time. On some occasions, the snails H. aspersa and C. pictum emitted a protective foam which enabled them to thwart the attack.
When the larvae were sufficiently grown, they pupated and the adult firefly later emerged. The identity of the imago
had not previously been known.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of firefly
Firefly
Lampyridae is a family of insects in the beetle order Coleoptera. They are winged beetles, and commonly called fireflies or lightning bugs for their conspicuous crepuscular use of bioluminescence to attract mates or prey. Fireflies produce a "cold light", with no infrared or ultraviolet frequencies...
in the beetle family Lampyridae, commonly known as the Cuban endemic firefly. The larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e of this species are predators on both pulmonate and operculate
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
land snail
Land snail
A land snail is any of the many species of snail that live on land, as opposed to those that live in salt water and fresh water. Land snails are terrestrial gastropod mollusks that have shells, It is not always an easy matter to say which species are terrestrial, because some are more or less...
s. Alecton discoidalis is the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
of the genus Alecton.
Distribution
Alecton is the only genusGenus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of firefly endemic to Cuba
Cuba
The Republic of Cuba is an island nation in the Caribbean. The nation of Cuba consists of the main island of Cuba, the Isla de la Juventud, and several archipelagos. Havana is the largest city in Cuba and the country's capital. Santiago de Cuba is the second largest city...
and A. discoidalis is the best known of the four species in that genus. It is found in the western half of the country. The type locality was described simply as "the island of Cuba".
Description
Alecton discoidalis was discovered and described (based on the larva only) by the French naturalist Francis de Laporte de Castelnau in 1833. His type description in FrenchFrench language
French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...
reads as follows:
This translates as: Yellow, with the tips of the antennae
Antenna (biology)
Antennae in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes....
and the elytra black, with a yellow border which starts a third of the way along the elytra.
Biology
The fireflies of Cuba have not been extensively studied. Research was undertaken in 2009 to examine the association of the larvae with terrestrialTerrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
gastropods and to learn more about the natural history of the species. Larvae of A. discoidalis were collected in limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
regions of Cuba where they were frequently found in the vicinity of snails. Most collections were made at night at which time the larvae could often be detected when they emitted flashes of light. Representatives of several different instar stages were gathered from leaf litter and from on or under rocks. At the same time, snails of a number of species were collected to determine which species would be the preferred prey
Predation
In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...
for the larvae. The temperature at the time of collection ranged from 26 to 32 °C and the humidity ranged from 64 to 86%. These levels were maintained in the laboratory during research.
The most vulnerable snails seemed to be those that live on the ground or rocks, but tree-dwelling species were also targeted occasionally. Acceptable prey species included snails from several families: family Helicinidae
Helicinidae
Helicinidae is a family of small tropical land snails which have an operculum. They are terrestrial operculate gastropod mollusks in the superfamily Helicinoidea....
(Helicina aspersa
Helicina aspersa
Helicina aspersa is a species of a land snail, terrestrial gastropod mollusk in the family Helicinidae.- Ecology :Helicina aspersa is a tree dwelling species....
, Ustronia sloanei
Ustronia sloanei
Ustronia sloanei is a species of an operculate land snail, terrestrial gastropod mollusk in the family Helicinidae.- Ecology :Ustronia sloanei is a rock dwelling species....
, Alcadia hispida
Alcadia hispida
Alcadia hispida is a species of an operculate land snail, terrestrial gastropod mollusk in the family Helicinidae.- Ecology :Alcadia hispida is a ground dwelling species....
, Emoda sagraiana
Emoda sagraiana
Emoda sagraiana is a species of an operculate land snail, terrestrial gastropod mollusk in the family Helicinidae.- Ecology :Emoda sagraiana is a ground dwelling species....
), family Pomatiidae
Pomatiidae
The family Pomatiidae is a taxonomic family of small operculate land snails, terrestrial gastropod mollusks that can be found over the warmer parts of the Old World. In the older literature, this family is designated as Pomatiasidae....
(Chondropoma pictum
Chondropoma pictum
Chondropoma pictum is a species of an operculate land snail, terrestrial gastropod mollusk in the family Pomatiidae.- Distribution :This species lives in Cuba, for example at Bacunayagua.- Ecology :...
, Chondropoma auberianum
Chondropoma auberianum
Chondropoma auberianum is a species of an operculate land snail, terrestrial gastropod mollusk in the family Pomatiidae.- Ecology :Chondropoma auberianum is a tree dwelling species....
, Chondropoma irradians
Chondropoma irradians
Chondropoma irradians is a species of an operculate land snail, terrestrial gastropod mollusk in the family Pomatiidae.- Ecology :Chondropoma irradians is a ground dwelling and rock dwelling species....
, Eutudora jimenoi
Eutudora jimenoi
Eutudora jimenoi is a species of an operculate land snail, terrestrial gastropod mollusk in the family Pomatiidae.- Ecology :Eutudora jimenoi is a rock dwelling species....
, Torrella immersa
Torrella immersa
Torrella immersa is a species of an operculate land snail, terrestrial gastropod mollusk in the family Pomatiidae.- Distribution :This species lives in Cuba, for example at Pan de Matanzas.- Ecology :This snail is usually a rock-dwelling species....
, Rhytidopoma coronatum
Rhytidopoma coronatum
Rhytidopoma coronatum is a species of an operculate land snail, terrestrial gastropod mollusk in the family Pomatiidae.- Distribution :This species lives in Cuba, for example at Escaleras de Jaruco.- Ecology :...
), family Megalomastomatidae
Megalomastomatidae
Megalomastomatidae is a family of tropical land snails with an operculum, terrestrial gastropod mollusks in the superfamily Cyclophoroidea .This family has no subfamilies.- Genera :...
(Farcimen tortum
Farcimen tortum
Farcimen tortum is a species of a land snail, terrestrial gastropod mollusk in the family Megalomastomatidae.- Ecology :Farcimen tortum is a ground dwelling species....
), family Oleacinidae
Oleacinidae
Oleacinidae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the clade Eupulmonata .-Anatomy:...
(Oleacina
Oleacina
Oleacina is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Oleacinidae.Oleacina is the type genus of the family Oleacinidae.-Species:Species within the genus Oleacina include:...
sp.) and family Polygyridae
Polygyridae
Polygyridae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Helicoidea.The Polygyridae make up a significant proportion of the land snail fauna of eastern North America, and are also found in western North America, northern Central America, and...
(Praticolella griseola
Praticolella griseola
Praticolella griseola is a species of a land snail, terrestrial gastropod mollusk in the family Polygyridae.- Distribution :Distribution of Praticolella griseola include Cuba....
).
Snails that were rejected by these larvae as food included Pycnoptychia
Pycnoptychia
Pycnoptychia is a genus of a land snails, terrestrial gastropod mollusks in the family Urocoptidae.- Species :Species in the genus Pycnoptychia include:* Pycnoptychia amicorum Torre & Bartsch, 2008...
species and Liguus fasciatus
Liguus fasciatus
Liguus fasciatus is a species of air-breathing land snail, a tree snail, a terrestrial pulmonate gastropod mollusk in the family Orthalicidae.- Subspecies :- Further reading :...
.
It was found that attacks took place both during the day and at night with the operculum
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
of the snail being targeted. The larva spent up to 24 hours inside the shell devouring the soft tissues. Sometimes several first-instar
Instar
An instar is a developmental stage of arthropods, such as insects, between each molt , until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or assume a new form. Differences between instars can often be seen in altered body proportions, colors, patterns, or...
larvae attacked a single snail at the same time. On some occasions, the snails H. aspersa and C. pictum emitted a protective foam which enabled them to thwart the attack.
When the larvae were sufficiently grown, they pupated and the adult firefly later emerged. The identity of the imago
Imago
In biology, the imago is the last stage of development of an insect, after the last ecdysis of an incomplete metamorphosis, or after emergence from the pupa where the metamorphosis is complete...
had not previously been known.