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Understanding SpeciesUnderstanding SpeciesImplications for IPMImplications for IPM
Malaria causes around 1.3 million deaths a Malaria causes around 1.3 million deaths a year worldwideyear worldwide
Control of malaria heavily relies on control Control of malaria heavily relies on control of its vector of its vector Anopheles maculipennisAnopheles maculipennis
What was thought to beWhat was thought to be A. maculipennis A. maculipennis was actually a complex of 7 specieswas actually a complex of 7 species
Different species of Different species of mosquitoes differ in their mosquitoes differ in their
ability to carry ability to carry
PlasmodiumPlasmodium
Presence of Presence of AnophelesAnopheles but not but not malaria mystery solved!malaria mystery solved!
Cryptic or Sibling SpeciesCryptic or Sibling Species
Cryptic or Sibling SpeciesCryptic or Sibling Species• Species that are virtually identical in Species that are virtually identical in
their morphologytheir morphology
Nilapavarta(Homoptera: Delphacidae)
Weed grass(Leersia hexandra)
Rice(Oryza sativa)
• Widespread in natureWidespread in nature
Cryptic or Sibling SpeciesCryptic or Sibling Species
• Present among insects of economic Present among insects of economic importanceimportance
Cryptic or Sibling SpeciesCryptic or Sibling Species
Bactrocera(Diptera: Tephritidae)
Oncopsis(Homoptera: Cicadellidae)
• Usually associated with different plant or Usually associated with different plant or host specieshost species
Cryptic or Sibling SpeciesCryptic or Sibling Species
Archips(Lepidoptera: Tortricidae)
ID of species on morphological grounds is ID of species on morphological grounds is often not good enoughoften not good enough
What initially seems to be a single poly or What initially seems to be a single poly or oligophagous species could represent a oligophagous species could represent a
collection of cryptic species collection of cryptic species
Nilapavarta(Homoptera: Delphacidae)
Weed grass(Leersia hexandra)
Rice(Oryza sativa)
What initially seems to be a single poly or What initially seems to be a single poly or oligophagous species could represent a oligophagous species could represent a
collection of cryptic species collection of cryptic species
Nilapavarta(Homoptera: Delphacidae)
Weed grass(Leersia hexandra)
Rice(Oryza sativa)
Aonidiella auranti(Homoptera: Margarodidae)
Correct identification of organisms is essential for Correct identification of organisms is essential for any intelligent interpretation of biological controlany intelligent interpretation of biological control
California
Red scale
Aonidiella auranti(Homoptera: Margarodidae)
Chrysomphalus
The red scale was originally classified in the The red scale was originally classified in the wrong genuswrong genus
The red and yellow scale insects were not The red and yellow scale insects were not separated taxonomically until 1937separated taxonomically until 1937
Aonidiella aurantii
Parasitoids of the yellow scale were introduced in Parasitoids of the yellow scale were introduced in California to control the red scale failing to California to control the red scale failing to
establishestablish
Aonidiella aurantii
China
California
Parasitoids of the yellow scale were introduced to Parasitoids of the yellow scale were introduced to California to control the red scale failing to California to control the red scale failing to
establishestablish
Aonidiella aurantii
China
California
It was concluded that no parasitoids to It was concluded that no parasitoids to control the red scale existed in Asiacontrol the red scale existed in Asia
Since 1880 an aphelinid parasitoid had been Since 1880 an aphelinid parasitoid had been known to attack red scale insectsknown to attack red scale insects
Red scale(Homoptera: Margarodidae)
California
Aphytis chrysomphali(Hymenoptera: Aphelinidae)
Compere found in China that the red scale insect Compere found in China that the red scale insect was kept at low densities by an was kept at low densities by an AphytisAphytis species species
ChinaGeorge CompereAphytis lingnanensis
(Hymenoptera: Aphelinidae)
The The AphytisAphytis species found by Compere was species found by Compere was identified as identified as Aphytis mytilaspidisAphytis mytilaspidis
George CompereAphytis lingnanensis
(Hymenoptera: Aphelinidae)
Aphytis mytilaspidis
Aphytis mytilaspidis
China
George CompereAphytis lingnanensis
(Hymenoptera: Aphelinidae)
Aphytis mytilaspidisCalifornia
Aphytis mytilaspidisAphytis mytilaspidis was already present in was already present in CaliforniaCalifornia
Aphyitis mytilaspidisAphyitis mytilaspidis does not attack red scale does not attack red scale insects in Californiainsects in California
George CompereAphytis lingnanensis
(Hymenoptera: Aphelinidae)
Aphytis mytilaspidisCalifornia
George CompereAphytis chrysomphali
(Hymenoptera: Aphelinidae)
Aphytis mytilaspidisCalifornia
Aphytis chrysomphaliAphytis chrysomphali, also present in California, , also present in California, was also erroneously named was also erroneously named A. mytilaspidisA. mytilaspidis
George CompereAphytis chrysomphali
(Hymenoptera: Aphelinidae)
Aphytis mytilaspidisCalifornia
Thus, it was erroneously concluded that the Thus, it was erroneously concluded that the parasitoid found in China controlling the red parasitoid found in China controlling the red
scale was already present in California scale was already present in California
• The 50 year failure of red scale insect control The 50 year failure of red scale insect control was based on a series of misidentifications.was based on a series of misidentifications.
• Searches made in SouthSearches made in South America instead of in Asia.America instead of in Asia.
• Introduction of unsuitable Introduction of unsuitable parasitoids.parasitoids.
• Failure to introduce the right parasitoid Failure to introduce the right parasitoid because it was misidentified as already present because it was misidentified as already present in California.in California.
The Red Scale Insect Control in The Red Scale Insect Control in CaliforniaCalifornia
• One of the best examples of a long term One of the best examples of a long term failure turned into a success by the failure turned into a success by the eventual introduction of appropriate eventual introduction of appropriate natural enemies.natural enemies.
• Illustrates the need to understand the Illustrates the need to understand the limits of cryptic species.limits of cryptic species.
Aphytis lingnanensis(Hymenoptera: Aphelinidae)
Can we predict where to expect cryptic Can we predict where to expect cryptic species to occur?species to occur?
Different activity cyclesDifferent activity cycles
4-5 weeks
Nocturnal
Diurnal
Specific mate recognition keeps species Specific mate recognition keeps species reproductively isolatedreproductively isolated
Some organisms recognize each other through tactiletactile or sonic clues
Coccophagus spp.
Others recognize each other through Others recognize each other through complex mating behaviorscomplex mating behaviors
If non visual ways of mate recognition are presentIf non visual ways of mate recognition are present
Exceptionally generalized habits or Exceptionally generalized habits or ecologies ?ecologies ?
Biological differences across spaceBiological differences across space
Biological differences across spaceBiological differences across space
So how can we tell?
= ?
Experimental approaches:Experimental approaches:
Behavioral observations in natureBehavioral observations in nature
b
Experimental approaches:Experimental approaches:
Cross-mating experimentsCross-mating experiments
x x
x
xa a
ab
a bb
Control ControlExperiment
a b
CAUTION!
CAUTION!
AllozymesAllozymes
&&
DNADNA
Molecular genetics techniquesMolecular genetics techniques
• Use as markers when limits Use as markers when limits have been defined by other have been defined by other means.means.
• Use to measure differences in allele Use to measure differences in allele frequencies to establish differentiation.frequencies to establish differentiation.
CytogeneticsCytogenetics
Polytene Chromosome
Analysis of mating signal structure and Analysis of mating signal structure and functionfunction
Cryptic Species Pose a Problem for Cryptic Species Pose a Problem for IPMIPM
• In assessments of:In assessments of:
- - Pest statusPest status
- Biocontrol potential- Biocontrol potential
- Host specificity- Host specificity
Cryptic Species Pose a Problem for Cryptic Species Pose a Problem for IPMIPM
• In assessments of:In assessments of:
- - Geographic distributionGeographic distribution
- Activity cycles- Activity cycles
- Pesticide resistance- Pesticide resistance