presentation on parasitic bees(cuckoo bees)

3.  cuckoo bumblebees belongs to separate genus
(Psithyrus) because of their distinctive appearance and
their behaviour as parasites in the colonies of other
bumblebees.
 In recent days - bumblebees belong to a single genus,
Bombus, with Psithyrus as a subgenus.

4.  Cuckoo bees are similar in appearance to bumblebees,
but they have a softer ‘buzz’, indeed Psithyrus means
‘murmuring’ as opposed to ‘Bombus’, which means
‘booming’.
 lack of pollen baskets on the legs
 sparser coat of hairs, through which the shiny black
cuticle can easily be seen.

5. Size
 Female length: 20-24 mm
 Male length: 15-19 mm

6.  Physical characteristics shared by many or most
parasitic bees (depending upon the characteristic)
include
 1) absence of scopa or corbiculum.
 2) reduced pilosity
 3) scale-like pubescence on some part of the body
 4) reduction or absence of basitibial plate.

7.  5) apical attenuation and specialization of abdomen
 6) strong, carinate, coarsely punctate exoskeleton
 7) bright or contrasting color pattern
 8) large (or at least unusually sharp) mandibles in
 one or more early larval instars
 9) unusual mobility of early larval instars.

8.  The term cuckoo bee is used for a variety of different
bee lineages which have evolved the kleptoparasitic
behaviour of laying their eggs in the nests of other
bees, reminiscent of the behavior of cuckoo birds.
 subfamily Nomadinae

9. How to identify females?
 Females of cuckoo bees - lack pollen collecting
structures (the scopa) and do not construct their own
nests.
 Reduced body hair,
 abnormally thick and/or heavily sculptured
exoskeleton,
 saber-like mandibles,

10.  They typically enter the nests of pollen-collecting
species, and lay their eggs in cells provisioned by the
host bee.
 the cuckoo bee larva hatches it consumes the host
larva's pollen ball.
 Also kills and eats the host larva.

11.  In zoology this way of making a living is known as
inquilinism (Latin inquilinus, meaning “lodger”), and
in bees it is surprisingly common.
 Several thousand species of bee follow this way of life.

12. "Cuckoo Bee" Parasite of the Squash Bee,
Xenoglossa strenua (Hymenoptera:
Apoidea)
 characteristic color pattern on the first two
metasomaltergites and the longitudinal pale marks on the
mesonotum distinguish it from other species in the genus.
 Deposits the egg in the cell wall. But with no cavity or other
sign leading to it is a mystery.
 cylindrical hole just accommodating the egg had been
made from the inside of the X. strenua cell before
oviposition took place.
 The adult female of this and other species of Triepeolus
 Females have a pair of long hooklet· hearing arms of the
sixth metasomal sternum flanking the sting.

13.  These arms must be used in the oviposition process

14. Xenoglossa strenua

15. SURVEY OF PARASITIC BEES
 Approximately 15 percent of the 4,000 to 5,000 species
of bees in America north of Mexico are parasitic. If the
same ratio holds in other parts of the world, there
should be a total of about 3,700 parasitic species.
 Of the nine families of bees, four are known to include
parasitic species. Of the 115 genera of bees in America
north of Mexico, 30 are exclusively parasitic.

16.  Honey bees
 Stingless Bees (Meliponinae)
 Bumble Bees (Bombus and Psithyrus
 Euglossine Bees
 Allodopine Bees
 Halictine Bees
 Parasitic Megachilidae
Coelioxys (Megachilini)
 Parasitic Anthidiines
 Melectine and Ericrocine Bees
 Nomadine Bees
 Protepeoline Bee

17. HONEY BEES (APIS)
 The common honey bee (A pis mellifera L.) is a
notorious robber of honey f bee colonies and
occasionally from other apid species.
 It usually robs during periods. Df poor natural forage,
and sometimes populous colonies completely "rob-out"
the stores of weaker ones, leaving them to starve.

18. STINGLESS BEES (MELIPONINAE)
 The genus Lestrimelitta, including
 two Neotropical and one Ethiopian species, is an
Dbligatory robber,
 apparently unable to Dbtain food stores directly from
flowe
 Neetropical species, Lestrimelitta limao (F. Smith),
usually confines its attack to' twO' subgenera of
stingless bees, and the African species, L. cubiceps
attacks only ene host species.

19.  Lestrimelitta- once they invade kills and drive off the
defending guards and establish their own guards to'
prevent defending bees from reentering.

20. Parasitic megachilidae
 An unrelated species, Osmia californica Cresson,
began using the lignaria nest.
 Coelioxys, with rare exceptions, attacks Megachile,
another genus in the same tribe.-inserts eggs into the
sealed host cell.
PARASITIC ANTHIDIINES
 Anthidiini is the only other megachilid tribe known to
have parasitic representatives.
 Two parasitic groups (Dioxys and the Stelis).

21.  Both groups are parasites of other megachilids. with.
the exception of a Stelis (subgenus Odontostelis) that
parasitizes Euglossa (Bennett, 1966).
 Dioxys lays its eggs on or near that of its host on tep of
the pollen mass. larva uses its sharp mandibles to kill
the host egg.
 Stelis sp the egg is often buried in the host's food
mass.attack is similar to Dioxys sp.

22. EUGLOSSINE BEES
 resemble bumble bees in many details of nest
construction and life history.
 Eulaema is parasitized by a beautiful metallic green
and blue euglossine, Exaraetae.
ALLODOPINE BEES
 Allodapula praesumptiosa is thought to be parasitic on
the basis of its morphological resemblance to A.
associata. Some of the morphological similarities may
represent modifications for a parasitic existence.

23. HALICTINE BEES
 This is a very large group of soil burrowing bees, most
of which form s
 Halictus scabiosae Although this species usually
constructs, provisions, and lays eggs in its own
nests,mall colonies. found that it often invades the
nests of anothe'r halictine, Evylaeus marginatus
(Knerer and Plateaux-Quenu 1967)
 drives out or kills the original halictid bees and takes
over the nest, building and provisioning cells in the
usual manner.

24.  Paralictus, like Sphecodes, is a halictine bee parasitic
on halictines.

25. Examples
 Sphecodes (parasitic primarily on halictines)
 Odontostelis (parasitic on euglossines) destroy the
host eggs or young larvae before ovipositing.
 Psithyrus parasitic on bumble bees.
 Lestrimelilta, a parasite of stingless bees, robs food
stores and building materials from its host species,

26.  Coelioxys rufitarsis, which parasitize the nests of a
common leafcutting bee, Megachile perihirta. The
female Coelioxys rufitarsis flies low over the ground in
search of a nest of Megachile perihirta, then waits
outside for her to leave so she can enter and lay her
own egg inside.

27.  Holcopasites heliopsis is a cuckoo bee – an egg-
munching, larva-killing parasite of the nests of other
bees.
 Parasitic genera usually attack only one host genus or a
few closely related ones. Nomada and Triepeolus are
outstanding exceptions.

28. A female cuckoo bee, Coelioxys rufitarsis. Epeolus minimus, a cuckoo bee
Xeromelecta californica on Aster x frikartii.A female cuckoo bee, Melecta separata callura