Jump to content

Eriopis connexa: Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
← Previous editNext edit →
Content deleted Content added
VisualWikitext
→‎Description: | Alter: template type. Add: pmid, pages, journal. Removed parameters. Some additions/deletions were parameter name changes. | Use this tool. Report bugs. | #UCB_Gadget
I have added to the introductory section, changed the picture in the taxobox, renamed the Distrubtion section "Geographic range" and added additional information, added a "Habitat" section, added information to the "Description" section, added a "Food resources" section, added a "Life history" section, added a "Reproduction" section with multiple subsections, added a "Interactions with humans" section with multiple subsectinos. In all new sections, I included additional information.
Line 2: Line 2:
{{mdy|date=May 2013}}
{{mdy|date=May 2013}}
{{Taxobox
{{Taxobox
| image = Econnexa.jpg
| image = Eriopis connexa 165685667.jpg
| image_caption = ''Eriopis connexa''
| image_caption = ''Eriopis connexa''
| regnum = [[Animal]]ia
| regnum = [[Animal]]ia
Line 18: Line 18:
}}
}}


'''''Eriopis connexa''''' is a [[species]] of [[Coccinellidae|ladybird beetle]] that is native to [[South America]]. Both males and females mate multiple times with different individuals of the opposite sex, making it a promiscuous species, like most members of the [[Coccinellidae]] family.<ref name=":0">{{Cite journal |last=Colares |first=Felipe |last2=Michaud |first2=J. P. |last3=Torres |first3=Jorge B. |last4=Silva-Torres |first4=Christian S. A. |date=2015-09 |title=Polyandry and Male Mating History Affect the Reproductive Performance of Eriopis connexa (Coleoptera: Coccinellidae) |url=https://academic.oup.com/aesa/article-lookup/doi/10.1093/aesa/sav056 |journal=Annals of the Entomological Society of America |language=en |volume=108 |issue=5 |pages=736–742 |doi=10.1093/aesa/sav056 |issn=0013-8746}}</ref> This promiscuous behavior leads to unique reproductive adaptations, such as sperm mixing. In order to boost offspring nutrition and reduce sibling cannibalism, females lay unfertilized eggs for their offspring to consume upon hatching.<ref name=":1">{{Cite journal |last=Silva |first=Alessandra C. G. |last2=Silva-Torres |first2=Christian S. A. |last3=Nascimento |first3=Deividy V. |last4=Torres |first4=Jorge B. |date=2021-11-01 |title=Sexual maturity, lack of partner choice and sperm precedence in the promiscuous ladybird beetle Eriopis connexa (Germar): Who is my father? |url=https://www.sciencedirect.com/science/article/pii/S0376635721001844 |journal=Behavioural Processes |volume=192 |pages=104500 |doi=10.1016/j.beproc.2021.104500 |issn=0376-6357}}</ref> This predatory beetle species feeds primarily on [[Aphid|aphids]] and is widespread throughout many agroecosystems, such as [[cotton]], [[maize]], [[sorghum]], [[soybean]], and [[wheat]].<ref name=":2">{{Cite journal |last=Spíndola |first=A. F. |last2=Silva-Torres |first2=C. S. A. |last3=Rodrigues |first3=A. R. S. |last4=Torres |first4=J. B. |date=2013-08 |title=Survival and behavioural responses of the predatory ladybird beetle, Eriopis connexa populations susceptible and resistant to a pyrethroid insecticide |url=https://www.cambridge.org/core/journals/bulletin-of-entomological-research/article/abs/survival-and-behavioural-responses-of-the-predatory-ladybird-beetle-eriopis-connexa-populations-susceptible-and-resistant-to-a-pyrethroid-insecticide/4957F73B384D45AD4EB3DAF58914FC53 |journal=Bulletin of Entomological Research |language=en |volume=103 |issue=4 |pages=485–494 |doi=10.1017/S0007485313000072 |issn=0007-4853}}</ref><ref name=":3">{{Cite journal |last=Rodrigues |first=Alice S. |last2=Botina |first2=Lisbetd |last3=Nascimento |first3=Carolina P. |last4=Gontijo |first4=Lessando M. |last5=Torres |first5=Jorge B. |last6=Guedes |first6=Raul Narciso C. |date=2016-10-01 |title=Ontogenic behavioral consistency, individual variation and fitness consequences among lady beetles |url=https://www.sciencedirect.com/science/article/pii/S0376635716301929 |journal=Behavioural Processes |volume=131 |pages=32–39 |doi=10.1016/j.beproc.2016.08.003 |issn=0376-6357}}</ref><ref name=":4">{{Cite journal |last=D’Ávila |first=Vinicius A. |last2=Barbosa |first2=Wagner F. |last3=Reis |first3=Lorene C. |last4=Gallardo |first4=Bianca S. A. |last5=Torres |first5=Jorge B. |last6=Guedes |first6=Raul Narciso C. |date=2018-05-01 |title=Lambda-cyhalothrin exposure, mating behavior and reproductive output of pyrethroid-susceptible and resistant lady beetles (Eriopis connexa) |url=https://www.sciencedirect.com/science/article/pii/S0261219418300097 |journal=Crop Protection |volume=107 |pages=41–47 |doi=10.1016/j.cropro.2018.01.009 |issn=0261-2194}}</ref> Due to aphids being extremely damaging agricultural pests, ''Eriopis connexa'' has been introduced to the United States for biological pest management.<ref name=":2" /> Recent studies on [[pyrethroid]] [[Pesticide resistance|insecticide resistance]] in ''Eriopis connexa'' have led to research by applied [[Entomology|entomologists]] on the species’ potential role in integrated pest management schemes in crop fields that rely on lambda-cyhalothrin (LCT), a common pyrethroid insecticide that is ineffective against aphid population control.<ref name=":2" /><ref name=":5">{{Cite journal |last=Ferreira |first=Emerson S. |last2=Rodrigues |first2=Agna R. S. |last3=Silva‐Torres |first3=Christian S. A. |last4=Torres |first4=Jorge B. |date=2013-05 |title=Life‐history costs associated with resistance to lambda‐cyhalothrin in the predatory ladybird beetle Eriopis connexa |url=https://resjournals.onlinelibrary.wiley.com/doi/10.1111/j.1461-9563.2012.00599.x |journal=Agricultural and Forest Entomology |language=en |volume=15 |issue=2 |pages=168–177 |doi=10.1111/j.1461-9563.2012.00599.x |issn=1461-9555}}</ref> The potential efficacy and success of the utilization of ''Eriopis connexa'' in these programs is widely debated and is the focus of much recent research due to the lack of understanding regarding the effects of pyrethroid resistance on the behavior of this species.<ref name=":0" />
'''''Eriopis connexa''''' is a widespread [[species]] of [[Coccinellidae|ladybird beetle]] in [[South America]].


==Geographic range==
==Distribution==
''Eriopis connexa'' is a [[Neotropical realm|neotropical]] species native to South America, but has been introduced to the [[United States]] for biological pest management.<ref name=":0" /><ref name=":2" />
⚫
''Eriopis connexa'' is one of the most widespread ladybird beetle of South America.<ref name="gonzalez peru">{{Cite web |last=González F. |first=Guillermo |title=Coccinellidae de Perú: Eriopis connexa |url=http://www.coccinellidae.cl/paginasWebPeru/Paginas/Eriopis_connexa_Peru.php |access-date=2021-07-23 |website=coccinellidae.cl |language=es}}</ref>


They may be found in [[Argentina]] (Buenos Aires, Catamarca, Córdoba, Chaco, Chubut, Entre Ríos, Formosa, La Rioja, Mendoza, Misiones, Neuquén, Río Negro, Salta, San Juan, Santa Fe, Santiago del Estero, Tucumán), [[Bolivia]] (Cochabamba, La Paz, Oruro), [[Brasil]] (Mato Grosso, Minas Gerais, Paraná, Pernambuco, Rio Grande do Sul, Santa Catarina, Sao Paulo), [[Ecuador]] (Guayas), [[Paraguay]] (Alto Paraná, Caazapá, Central, Kanindeyu, Paraguarí, Pte. Hayes, San Pedro), [[Perú]] (Apurimac, Arequipa, Ayacucho, Cusco, Lima), [[Uruguay]] (Florida, Maldonado, Montevideo, San José), [[Venezuela]].<ref name="gonzalez arg">{{Cite web |title=Eriopis connexa - Coccinellidae de Argentina |url=https://www.coccinellidae.cl/paginasWebArg/Paginas/Eriopis_connexa_Arg.php |access-date=2021-07-23 |website=coccinellidae.cl |language=es}}</ref>
They may be found in [[Argentina]] (Buenos Aires, Catamarca, Córdoba, Chaco, Chubut, Entre Ríos, Formosa, La Rioja, Mendoza, Misiones, Neuquén, Río Negro, Salta, San Juan, Santa Fe, Santiago del Estero, Tucumán), [[Bolivia]] (Cochabamba, La Paz, Oruro), [[Brasil]] (Mato Grosso, Minas Gerais, Paraná, Pernambuco, Rio Grande do Sul, Santa Catarina, Sao Paulo), [[Ecuador]] (Guayas), [[Paraguay]] (Alto Paraná, Caazapá, Central, Kanindeyu, Paraguarí, Pte. Hayes, San Pedro), [[Perú]] (Apurimac, Arequipa, Ayacucho, Cusco, Lima), [[Uruguay]] (Florida, Maldonado, Montevideo, San José), [[Venezuela]].<ref name="gonzalez arg">{{Cite web |title=Eriopis connexa - Coccinellidae de Argentina |url=https://www.coccinellidae.cl/paginasWebArg/Paginas/Eriopis_connexa_Arg.php |access-date=2021-07-23 |website=coccinellidae.cl |language=es}}</ref>

== Habitat ==
This beetle species is found throughout a wide variety of [[Agroecosystem|agroecosystems]], such as cotton, maize, sorghum, [[pine]], [[citrus]], soybean, and wheat plants.<ref name=":2" /><ref name=":3" /><ref name=":4" /><ref name=":6">{{Cite journal |last=de Matos |first=Sidnéia Terezinha Soares |last2=Savi |first2=Patrice Jacob |last3=Melville |first3=Cirano Cruz |last4=dos Santos Cividanes |first4=Terezinha Monteiro |last5=Cividanes |first5=Francisco Jorge |last6=de Andrade |first6=Daniel Júnior |date=2022-05-16 |title=Suitability of spider mites and green peach aphids as prey for Eriopis connexa (Germar) (Coleoptera: Coccinellidae) |url=https://www.nature.com/articles/s41598-022-12078-8 |journal=Scientific Reports |language=en |volume=12 |issue=1 |pages=8029 |doi=10.1038/s41598-022-12078-8 |issn=2045-2322 |pmc=PMC9110729 |pmid=35577880}}</ref> In attempts to broaden the pest management potential of ''Eriopis connexa'', studies have indicated this predatory beetle species is effective in controlling aphid populations on both [[cabbage]] plants and greenhouse [[strawberry]] plants, suggesting there is greater range in potential ''E. connexa'' habitat than originally thought.<ref name=":6" />


==Description==
==Description==
[[File:Eriopis connexa1.jpg|thumb|Lateral view of ''Eriopis connexa'']]
''Eriopis connexa'' has an oblong body shape. The base color dark brown to black with yellowish relatively large, separated dots. The [[pronotum]] and the [[elytron|elytra]] (wing covers) have a yellowish margin. Each elytron has three separated dots and the enlargements of the margin, the pronotum two smaller dots and two enlargements of the margin.<ref name="gonzalez peru" />
⚫
''Eriopis connexa'' has an oblong body shape. The base color dark brown to black with yellowish relatively large, separated dots. The [[pronotum]] and the [[elytron|elytra]] (wing covers) have a yellowish margin. Each elytron has three separated dots and the enlargements of the margin, the pronotum two smaller dots and two enlargements of the margin.<ref name="gonzalez peru">{{Cite web |last=González F. |first=Guillermo |title=Coccinellidae de Perú: Eriopis connexa |url=http://www.coccinellidae.cl/paginasWebPeru/Paginas/Eriopis_connexa_Peru.php |access-date=2021-07-23 |website=coccinellidae.cl |language=es}}</ref>

There are not always visible indications of [[sexual dimorphism]] in this beetle species, but at certain times in adulthood, females will have extended abdomens for egg production.<ref name=":1" /> Additionally, adult females can be distinguished from adult males by their significantly heavier weight.<ref name=":5" />

== Food resources ==
[[File:Aphid on leaf05.jpg|left|thumb|Aphid]]
''Eriopis connexa'' is known for its voracious aphid [[predation]].<ref name=":2" /> Still, it is not limited to aphid consumption as it is a polyphagous species and also consumes [[Scale insect|scale insects]], [[Mite|mites]], [[Lepidoptera|lepidopteran]] eggs, and [[Whitefly|whiteflies]] as supplementary prey.<ref name=":0" /><ref name=":2" /><ref name=":5" /> Furthermore, studies indicate that this beetle species is able to survive and successfully reproduce when solely consuming certain species of [[Spider mite|spider mites]] ([[Tetranychus urticae|''Tetranychus'' ''urticae'']] and ''Tetranychus ogmophallos''). These studies also indicate that the species of prey does strongly influence ''Eriopis connexa'' development, survival, and reproduction, and aphid consumption leads to optimal demographic outcomes. Host plants' chemical, morphological, and allelochemical features affect the nutritional value of arthropods, further complicating potential biological pest management.<ref name=":6" />

== Life History ==
[[File:Eriopis connexa 165274686.jpg|thumb|222x222px|''Eriopis connexa'' in larval stage]]
There are five main sequential stages of development in ''Eriopis connexa'': [[egg]], [[larva]], pre-pupa, [[pupa]], and adult. The larval stage can be further broken into four [[Instar|instars]]. Laboratory studies indicate that individuals spend approximately two days in each of the first three instar stages, nearly four days in the fourth instar stage, one day in the pre-pupa stage, three to four days in the pupa stage, and the rest of their lives in the adult stage.<ref name=":6" /> Individuals usually live for around 60 days in total. Both males and females reach full [[sexual maturity]] on the fifth day of the adult stage. Individuals of both sexes are sexually receptive on the third day but are not yet at their maximum [[fertility]] and [[fecundity]]. This may be due to incomplete maturation of [[Sex organ|sexual organs]].<ref name=":1" />

== Reproduction ==

=== Promiscuity and sperm mixing ===
Both males and females mate multiple times with different individuals of the opposite sex, making ''Eriopis connexa'' a promiscuous species like most members of its family.<ref name=":0" /> [[Polyandry]] is known to increase [[genetic diversity]] and offspring vigor, as well as allow for [[sperm competition]], although increased matings sometimes present costs to females. In this beetle species, male [[Spermatozoon|spermatozoa]] are directly transferred to females through insemination not packaged in [[Spermatophore|spermatophores]], as in many other insect species. Mating order in ''Eriopis connexa'' does not affect offspring paternity and thus suggests sperm mixing is present in the female [[spermatheca]]. Sperm mixing is a powerful evolutionarily adaptive mechanism that favors the selection of superior sperm and results in sperm superior to that of [[Monogamy|monogamous]] species.<ref name=":1" />

=== Trophic eggs ===
Female ''Eriopis connexa'' never reach 100% fertility because they lay unfertilized, [[Trophic egg|trophic eggs]] in order to provide additional nutrition for their offspring when they hatch into larvae. Studies indicate that when ''E. connexa'' larvae are removed from their natal egg batch directly upon hatching, they experience lower survival rates than larvae allowed to remain on top of their natal egg batch for several hours. Even though there are costs for females to produce [[Oocyte|oocytes]], laying trophic eggs is an evolutionary adaptation that improves larval nutrition and reduces sibling cannibalism.<ref name=":1" />

=== Copulatory behaviors ===
Laboratory studies indicate that this beetle species will initiate [[Sexual intercourse|copulation]] in under one minute of being allowed access to the opposite sex. Copulation duration does not affect fertility, and mating usually lasts for around 24 minutes. In closely related species of ladybird beetle (''[[Harmonia axyridis|H. axyridis]]''), males exhibit a body-shaking behavior when transferring spermatozoa to females, but this behavior is not present in male ''E. connexa''. A similar body-shaking behavior is, however, present in female ''E. connexa'', but in this species, the behavior is exhibited once at the start of copulation and once more to shake the male off and terminate the copulation. Post-copulatory behaviors such as female guarding, ejection and ingestion of seminal material have not been observed in ''E. connexa.''<ref name=":1" />

=== Male mating history ===
In many ''Coccinella'' species, egg viability is negatively correlated with [[Father|paternal]] sexual activity, but this trend is not present in ''Eriopis connexa'', suggesting males in this species have adapted to more frequent matings. There is, however, a negative correlation between oviposition time and paternal sexual activity in ''E. connexa'', suggesting that [[Allomone|allomones]] in male seminal fluid stimulate faster onset of oviposition in females and virgin males have greater quantities of allomones present in their seminal fluid. Allomonal effects in seminal fluid proteins can also create subtle paternal effects, such as increased offspring size or development time, but paternal effects are not present in ''E. connexa'', suggesting males and females of this species have similar interests in [[Offspring|progeny]] [[Phenotype|phenotypes]].<ref name=":0" />

== Interactions with humans ==

=== Biological pest control ===
Because ''Eriopis connexa'' is a voracious predator of aphids, a very destructive agricultural pest, and naturally occurs in crops of high economic importance, this predatory beetle species has been used frequently for biological control of pests. It was first introduced to the United States in order to control Russian wheat aphid (''Diuraphasis norxia'') populations.<ref name=":2" /> As insecticide resistance continues to evolve in many agricultural pests, alternative pest control methods have become more desirable and necessary.<ref name=":6" />

=== Pyrethroid insecticide resistance ===
[[File:2017. Pesticide “Lambda cyhalothrin” being used with ground based misting equipment for forest caterpillar control. Bulgan Province, Mongolia. (39581880771).jpg|left|thumb|256x256px|Lambda-cyhalothrin (LCT)]]
Pyrethroid insecticides are commonly used to target agricultural pests, such as [[Boll weevil|boll weevils]]. Lambda-cyhalothrin, also known as LCT,  is a common pyrethroid insecticide that is ineffective at controlling aphid populations. Laboratory experiments involving breeding generations of ''Eriopis connexa'' under increasing concentrations of lambda-cyhalothrin result in pyrethroid-resistant ''Eriopis connexa'' individuals.<ref name=":2" /> Later studies revealed pyrethroid resistance follows [[Autosome|autosomal]] and [[Dominance (genetics)|semi-dominant]] inheritance patterns in this beetle species. This phenotype is associated with enhanced detoxification [[enzyme]] activity, which corresponds to the [[Neurotoxicity|neurotoxic]] properties of pyrethroid insecticides. Furthermore, the pyrethroid resistance is not restricted to a single insecticide (such as LCT) and instead applies to multiple types of pyrethroid insecticides.<ref name=":4" />

=== Effect of pyrethroid insecticide resistance on reproductive success ===
Selection pressure for resistance can lead to reduced performance in which resistant individuals are at a disadvantage when the selection pressure is removed. In the case of ''Eriopis connexa'' and pyrethroid resistance, the resistant phenotype is associated with decreased [[reproductive success]].<ref name=":5" /> Pyrethroid-resistant females exhibit delayed egg-laying and reduced fecundity. Since pyrethroid resistance is not associated with an identifiable physical trait, females show no preference for or against it. Because sperm mixing is present in this species, some researchers suggest the first-generation offspring between a population of pyrethroid-susceptible ''Eriopis connexa'' and a released population of pyrethroid-resistant individuals will result in half of the offspring having the pyrethroid-resistant phenotype.<ref name=":1" /> Pyrethroid resistance is also associated with behavioral changes in ''Eriopis connexa'', in which individuals take longer times to interact, females shake their body for a longer time prior to copulation, and males and females mate less frequently than the pyrethroid-susceptible individuals.<ref name=":4" />


=== Potential issues in utilization of pyrethroid-resistant individuals ===
Eriopis connexa is a voracious predator of [[aphids]].<ref name=" gonzalez peru"/><ref name="Spíndola">{{Cite journal |last=Torres JB |url=https://www.cambridge.org/core/journals/bulletin-of-entomological-research/article/abs/survival-and-behavioural-responses-of-the-predatory-ladybird-beetle-eriopis-connexa-populations-susceptible-and-resistant-to-a-pyrethroid-insecticide/4957F73B384D45AD4EB3DAF58914FC53 |title=Survival and behavioural responses of the predatory ladybird beetle, Eriopis connexa populations susceptible and resistant to a pyrethroid insecticide |date=2013-03-22 |journal=Bulletin of Entomological Research |volume=103 |doi=10.1017/S0007485313000072 |issue=4|pages=485–494 |pmid=23522490 }}</ref>
Some researchers suggest [[Ecology|ecological]] mismatches between pyrethroid-resistant ''Eriopis connexa'' and agroecosystems will lead to adverse outcomes that won’t be discovered through laboratory assays.<ref name=":0" /> Other concerns originate in the adaptive cost of resistance incurred by the pyrethroid-resistant females as they may cause pyrethroid-resistant individuals to be replaced by pyrethroid-susceptible populations in extended periods of low pyrethroid usage.<ref name=":4" /><ref name=":5" /> Additionally, behavioral studies indicate decreased [[aggression]] in pyrethroid-resistant ''Eriopis connexa'' individuals, which may harm their efficacy of predation of agricultural pests.<ref name=":3" /> Another potential problem of utilizing ''Eriopis connexa'' in an integrated pest management scheme is that they forage for food in plant [[Canopy (biology)|canopies]], which can result in greater exposure to sprayed pesticides than even the target pests themselves.<ref name=":5" />


==References==
==References==

Revision as of 02:54, 1 March 2024

Eriopis connexa
Eriopis connexa
Scientific classification
Kingdom:
Animalia
Phylum:
Arthropoda
Class:
Insecta
Order:
Coleoptera
Family:
Coccinellidae
Subfamily:
Coccinellinae
Tribe:
Coccinellini
Genus:
Eriopis
Species:
E. connexa
Binomial name
Eriopis connexa
(Germar, 1824)
Synonyms
  • Coccinella connexa Germar, 1824

Eriopis connexa is a species of ladybird beetle that is native to South America. Both males and females mate multiple times with different individuals of the opposite sex, making it a promiscuous species, like most members of the Coccinellidae family.[1] This promiscuous behavior leads to unique reproductive adaptations, such as sperm mixing. In order to boost offspring nutrition and reduce sibling cannibalism, females lay unfertilized eggs for their offspring to consume upon hatching.[2] This predatory beetle species feeds primarily on aphids and is widespread throughout many agroecosystems, such as cotton, maize, sorghum, soybean, and wheat.[3][4][5] Due to aphids being extremely damaging agricultural pests, Eriopis connexa has been introduced to the United States for biological pest management.[3] Recent studies on pyrethroid insecticide resistance in Eriopis connexa have led to research by applied entomologists on the species’ potential role in integrated pest management schemes in crop fields that rely on lambda-cyhalothrin (LCT), a common pyrethroid insecticide that is ineffective against aphid population control.[3][6] The potential efficacy and success of the utilization of Eriopis connexa in these programs is widely debated and is the focus of much recent research due to the lack of understanding regarding the effects of pyrethroid resistance on the behavior of this species.[1]

Geographic range

Eriopis connexa is a neotropical species native to South America, but has been introduced to the United States for biological pest management.[1][3]

They may be found in Argentina (Buenos Aires, Catamarca, Córdoba, Chaco, Chubut, Entre Ríos, Formosa, La Rioja, Mendoza, Misiones, Neuquén, Río Negro, Salta, San Juan, Santa Fe, Santiago del Estero, Tucumán), Bolivia (Cochabamba, La Paz, Oruro), Brasil (Mato Grosso, Minas Gerais, Paraná, Pernambuco, Rio Grande do Sul, Santa Catarina, Sao Paulo), Ecuador (Guayas), Paraguay (Alto Paraná, Caazapá, Central, Kanindeyu, Paraguarí, Pte. Hayes, San Pedro), Perú (Apurimac, Arequipa, Ayacucho, Cusco, Lima), Uruguay (Florida, Maldonado, Montevideo, San José), Venezuela.[7]

Habitat

This beetle species is found throughout a wide variety of agroecosystems, such as cotton, maize, sorghum, pine, citrus, soybean, and wheat plants.[3][4][5][8] In attempts to broaden the pest management potential of Eriopis connexa, studies have indicated this predatory beetle species is effective in controlling aphid populations on both cabbage plants and greenhouse strawberry plants, suggesting there is greater range in potential E. connexa habitat than originally thought.[8]

Description

Lateral view of Eriopis connexa

Eriopis connexa has an oblong body shape. The base color dark brown to black with yellowish relatively large, separated dots. The pronotum and the elytra (wing covers) have a yellowish margin. Each elytron has three separated dots and the enlargements of the margin, the pronotum two smaller dots and two enlargements of the margin.[9]

There are not always visible indications of sexual dimorphism in this beetle species, but at certain times in adulthood, females will have extended abdomens for egg production.[2] Additionally, adult females can be distinguished from adult males by their significantly heavier weight.[6]

Food resources

Aphid

Eriopis connexa is known for its voracious aphid predation.[3] Still, it is not limited to aphid consumption as it is a polyphagous species and also consumes scale insects, mites, lepidopteran eggs, and whiteflies as supplementary prey.[1][3][6] Furthermore, studies indicate that this beetle species is able to survive and successfully reproduce when solely consuming certain species of spider mites (Tetranychus urticae and Tetranychus ogmophallos). These studies also indicate that the species of prey does strongly influence Eriopis connexa development, survival, and reproduction, and aphid consumption leads to optimal demographic outcomes. Host plants' chemical, morphological, and allelochemical features affect the nutritional value of arthropods, further complicating potential biological pest management.[8]

Life History

Eriopis connexa in larval stage

There are five main sequential stages of development in Eriopis connexa: egg, larva, pre-pupa, pupa, and adult. The larval stage can be further broken into four instars. Laboratory studies indicate that individuals spend approximately two days in each of the first three instar stages, nearly four days in the fourth instar stage, one day in the pre-pupa stage, three to four days in the pupa stage, and the rest of their lives in the adult stage.[8] Individuals usually live for around 60 days in total. Both males and females reach full sexual maturity on the fifth day of the adult stage. Individuals of both sexes are sexually receptive on the third day but are not yet at their maximum fertility and fecundity. This may be due to incomplete maturation of sexual organs.[2]

Reproduction

Promiscuity and sperm mixing

Both males and females mate multiple times with different individuals of the opposite sex, making Eriopis connexa a promiscuous species like most members of its family.[1] Polyandry is known to increase genetic diversity and offspring vigor, as well as allow for sperm competition, although increased matings sometimes present costs to females. In this beetle species, male spermatozoa are directly transferred to females through insemination not packaged in spermatophores, as in many other insect species. Mating order in Eriopis connexa does not affect offspring paternity and thus suggests sperm mixing is present in the female spermatheca. Sperm mixing is a powerful evolutionarily adaptive mechanism that favors the selection of superior sperm and results in sperm superior to that of monogamous species.[2]

Trophic eggs

Female Eriopis connexa never reach 100% fertility because they lay unfertilized, trophic eggs in order to provide additional nutrition for their offspring when they hatch into larvae. Studies indicate that when E. connexa larvae are removed from their natal egg batch directly upon hatching, they experience lower survival rates than larvae allowed to remain on top of their natal egg batch for several hours. Even though there are costs for females to produce oocytes, laying trophic eggs is an evolutionary adaptation that improves larval nutrition and reduces sibling cannibalism.[2]

Copulatory behaviors

Laboratory studies indicate that this beetle species will initiate copulation in under one minute of being allowed access to the opposite sex. Copulation duration does not affect fertility, and mating usually lasts for around 24 minutes. In closely related species of ladybird beetle (H. axyridis), males exhibit a body-shaking behavior when transferring spermatozoa to females, but this behavior is not present in male E. connexa. A similar body-shaking behavior is, however, present in female E. connexa, but in this species, the behavior is exhibited once at the start of copulation and once more to shake the male off and terminate the copulation. Post-copulatory behaviors such as female guarding, ejection and ingestion of seminal material have not been observed in E. connexa.[2]

Male mating history

In many Coccinella species, egg viability is negatively correlated with paternal sexual activity, but this trend is not present in Eriopis connexa, suggesting males in this species have adapted to more frequent matings. There is, however, a negative correlation between oviposition time and paternal sexual activity in E. connexa, suggesting that allomones in male seminal fluid stimulate faster onset of oviposition in females and virgin males have greater quantities of allomones present in their seminal fluid. Allomonal effects in seminal fluid proteins can also create subtle paternal effects, such as increased offspring size or development time, but paternal effects are not present in E. connexa, suggesting males and females of this species have similar interests in progeny phenotypes.[1]

Interactions with humans

Biological pest control

Because Eriopis connexa is a voracious predator of aphids, a very destructive agricultural pest, and naturally occurs in crops of high economic importance, this predatory beetle species has been used frequently for biological control of pests. It was first introduced to the United States in order to control Russian wheat aphid (Diuraphasis norxia) populations.[3] As insecticide resistance continues to evolve in many agricultural pests, alternative pest control methods have become more desirable and necessary.[8]

Pyrethroid insecticide resistance

Lambda-cyhalothrin (LCT)

Pyrethroid insecticides are commonly used to target agricultural pests, such as boll weevils. Lambda-cyhalothrin, also known as LCT,  is a common pyrethroid insecticide that is ineffective at controlling aphid populations. Laboratory experiments involving breeding generations of Eriopis connexa under increasing concentrations of lambda-cyhalothrin result in pyrethroid-resistant Eriopis connexa individuals.[3] Later studies revealed pyrethroid resistance follows autosomal and semi-dominant inheritance patterns in this beetle species. This phenotype is associated with enhanced detoxification enzyme activity, which corresponds to the neurotoxic properties of pyrethroid insecticides. Furthermore, the pyrethroid resistance is not restricted to a single insecticide (such as LCT) and instead applies to multiple types of pyrethroid insecticides.[5]

Effect of pyrethroid insecticide resistance on reproductive success

Selection pressure for resistance can lead to reduced performance in which resistant individuals are at a disadvantage when the selection pressure is removed. In the case of Eriopis connexa and pyrethroid resistance, the resistant phenotype is associated with decreased reproductive success.[6] Pyrethroid-resistant females exhibit delayed egg-laying and reduced fecundity. Since pyrethroid resistance is not associated with an identifiable physical trait, females show no preference for or against it. Because sperm mixing is present in this species, some researchers suggest the first-generation offspring between a population of pyrethroid-susceptible Eriopis connexa and a released population of pyrethroid-resistant individuals will result in half of the offspring having the pyrethroid-resistant phenotype.[2] Pyrethroid resistance is also associated with behavioral changes in Eriopis connexa, in which individuals take longer times to interact, females shake their body for a longer time prior to copulation, and males and females mate less frequently than the pyrethroid-susceptible individuals.[5]

Potential issues in utilization of pyrethroid-resistant individuals

Some researchers suggest ecological mismatches between pyrethroid-resistant Eriopis connexa and agroecosystems will lead to adverse outcomes that won’t be discovered through laboratory assays.[1] Other concerns originate in the adaptive cost of resistance incurred by the pyrethroid-resistant females as they may cause pyrethroid-resistant individuals to be replaced by pyrethroid-susceptible populations in extended periods of low pyrethroid usage.[5][6] Additionally, behavioral studies indicate decreased aggression in pyrethroid-resistant Eriopis connexa individuals, which may harm their efficacy of predation of agricultural pests.[4] Another potential problem of utilizing Eriopis connexa in an integrated pest management scheme is that they forage for food in plant canopies, which can result in greater exposure to sprayed pesticides than even the target pests themselves.[6]

References

  1. ^ a b c d e f g Colares, Felipe; Michaud, J. P.; Torres, Jorge B.; Silva-Torres, Christian S. A. (2015-09). "Polyandry and Male Mating History Affect the Reproductive Performance of Eriopis connexa (Coleoptera: Coccinellidae)". Annals of the Entomological Society of America. 108 (5): 736–742. doi:10.1093/aesa/sav056. ISSN 0013-8746. {{cite journal}}: Check date values in: |date= (help)
  2. ^ a b c d e f g Silva, Alessandra C. G.; Silva-Torres, Christian S. A.; Nascimento, Deividy V.; Torres, Jorge B. (November 1, 2021). "Sexual maturity, lack of partner choice and sperm precedence in the promiscuous ladybird beetle Eriopis connexa (Germar): Who is my father?". Behavioural Processes. 192: 104500. doi:10.1016/j.beproc.2021.104500. ISSN 0376-6357.
  3. ^ a b c d e f g h i Spíndola, A. F.; Silva-Torres, C. S. A.; Rodrigues, A. R. S.; Torres, J. B. (2013-08). "Survival and behavioural responses of the predatory ladybird beetle, Eriopis connexa populations susceptible and resistant to a pyrethroid insecticide". Bulletin of Entomological Research. 103 (4): 485–494. doi:10.1017/S0007485313000072. ISSN 0007-4853. {{cite journal}}: Check date values in: |date= (help)
  4. ^ a b c Rodrigues, Alice S.; Botina, Lisbetd; Nascimento, Carolina P.; Gontijo, Lessando M.; Torres, Jorge B.; Guedes, Raul Narciso C. (October 1, 2016). "Ontogenic behavioral consistency, individual variation and fitness consequences among lady beetles". Behavioural Processes. 131: 32–39. doi:10.1016/j.beproc.2016.08.003. ISSN 0376-6357.
  5. ^ a b c d e D’Ávila, Vinicius A.; Barbosa, Wagner F.; Reis, Lorene C.; Gallardo, Bianca S. A.; Torres, Jorge B.; Guedes, Raul Narciso C. (May 1, 2018). "Lambda-cyhalothrin exposure, mating behavior and reproductive output of pyrethroid-susceptible and resistant lady beetles (Eriopis connexa)". Crop Protection. 107: 41–47. doi:10.1016/j.cropro.2018.01.009. ISSN 0261-2194.
  6. ^ a b c d e f Ferreira, Emerson S.; Rodrigues, Agna R. S.; Silva‐Torres, Christian S. A.; Torres, Jorge B. (2013-05). "Life‐history costs associated with resistance to lambda‐cyhalothrin in the predatory ladybird beetle Eriopis connexa". Agricultural and Forest Entomology. 15 (2): 168–177. doi:10.1111/j.1461-9563.2012.00599.x. ISSN 1461-9555. {{cite journal}}: Check date values in: |date= (help)
  7. ^ "Eriopis connexa - Coccinellidae de Argentina". coccinellidae.cl (in Spanish). Retrieved July 23, 2021.
  8. ^ a b c d e de Matos, Sidnéia Terezinha Soares; Savi, Patrice Jacob; Melville, Cirano Cruz; dos Santos Cividanes, Terezinha Monteiro; Cividanes, Francisco Jorge; de Andrade, Daniel Júnior (May 16, 2022). "Suitability of spider mites and green peach aphids as prey for Eriopis connexa (Germar) (Coleoptera: Coccinellidae)". Scientific Reports. 12 (1): 8029. doi:10.1038/s41598-022-12078-8. ISSN 2045-2322. PMC 9110729. PMID 35577880.{{cite journal}}: CS1 maint: PMC format (link)
  9. ^ González F., Guillermo. "Coccinellidae de Perú: Eriopis connexa". coccinellidae.cl (in Spanish). Retrieved July 23, 2021.


Stub icon

This Coccinellidae-related article is a stub. You can help Wikipedia by expanding it.

Retrieved from "https://en.wikipedia.org/w/index.php?title=Eriopis_connexa&oldid=1211150460"