Presentaci

1
Beijing Wokshop, September 2002 Larval food
(Artemia), larviculture and ecotoxicology group
(UE partner 4) Members Dr. Francisco
Amat Dr. Francisco Hontoria Dr. Juan Carlos
Navarro Dr. Inmaculada Varó Óscar
Monroig Germán Medina Olga Ruiz
Instituto de Acuicultura de Torre de la Sal
Consejo Superior de Investigaciones Científicas
12595 Ribera de Cabanes (Castellón)
SPAIN
2

• Distribution of A. persimilis and A. franciscana
  populations in Argentina
• Presence of rare males in diploid parthenogenetic
  Artemia populations from the Old World
• Updating of cyst bank and database

3

• Distribution of A. persimilis and A. franciscana
  populations in Argentina (1)
• Presence of Artemia franciscana North of 36º S
  and A. persimilis South of 37º S.
• The population of A. franciscana from Las Tunas
  lagoon (33º 44S) evidences a phenomenon of
  hybridisation or introgression 50 males show
  n22 chromosomes, and 50 n21 chromosomes.
• Laboratory crossbreeding experiments show
  reproductive isolation between A. franciscana
  (Mar Chiquita, Las Tunas) and A. persimilis
  (Salinas Grandes de Hidalgo) Argentinean
  populations.
• Laboratory population from Las Tunas crossbreeds
  with Mar Chiquita (A. franciscana) population,
  and does not with Salinas Grandes de Hidalgo (A.
  persimilis) population.

4
(No Transcript)
5
Females
6
Males
7

• Distribution of A. persimilis and A. franciscana
  populations in Argentina (2)
• Laboratory populations from A. franciscana and A.
  persimilis in competition show different
  reproductive output in terms of
  oviparism/ovoviviparism.
• Under suboptimal conditions of food availability
  A. persimils shifts immediately to oviparism,
  while A. franciscana always keeps moderate levels
  of ovoviviparism (gt 13 )
• Under the same conditions (environmental, food
  availability) co-occurring populations from both
  species show different reproductive output. A.
  franciscana females show always higher fecundity
  than A. persimilis females.
• Former results explain a competitive development
  under which A. franciscana population outcompetes
  completely A. persimilis .

8
(No Transcript)
9
(No Transcript)
10
(No Transcript)
11
(No Transcript)
12

• Presence of rare males in diploid parthenogenetic
  Artemia populations from the Old World (1)
•  
• Rare males were found in 22 populations of
  Artemia parthenogenetica (diploid) from the Old
  World 9 populations in the Iberian peninsula
  (Spain and Portugal), 2 populations from Africa
  (Namibia and Egypt), and 11 populations from
  Eurasia (Italy, Ukraine, West Altai, Kazakhstan,
  Mongolia, China, Iran and India).
• These rare males are morphologically different
  from those present in bisexual species or
  populations.
• This atavism is more frequent in
  parthenogenetic populations from Central Eurasia
  (Iran, Kazakhstan, Ukraine, Mongolia) and less
  frequent, or scarce, in peripheral Western
  (Iberian peninsula, Africa) and Eastern (China)
  populations.

13

• Presence of rare males in diploid parthenogenetic
  Artemia populations from the Old World (2)
•  
• Although rare males seem useless in reproductive
  strategies for parthenogenetic females, they are
  not sterile. They can mate and fertilize females
  from the bisexual strains or populations Artemia
  urmiana (lake Urmia, Iran) and Artemia sinica
  (lake Yuncheng, Shanxi, China), producing live
  offspring .
• It is suspected that this rare male atavism could
  help to explain the origin of parthenogenetic
  strains (monophyletic?, polyphyletic?) from
  lineages leading to present-day Asiatic Artemia
  or from hybridization between two of the Asiatic
  bisexual species (A. urmiana and A. sinica).

14
Quantification of rare males found in diploid
parthenogenetic populations of Artemia   N
number of individuals studied from laboratory
populations male/1000 ? ratio of males to 1000
individuals     Origin N male/ Origin
N male/ 1000 1000   SPAIN and
PORTUGAL EURASIA La Mata lagoon
(Alicante) 16,197 2-3 Marg. di Savoia salterns
(Italy) 12,103 1 Janubio salterns
(Lanzarote) 13,092 0 Santa Gilla salterns
(Italy) 4,647 1 Odiel salterns
(Huelva) 14,188 1 Kujalnik lake,
Ukraina 12,656 7-8 Sanlucar salterns
(Cádiz) 12,202 1 Maloje Jar. Lake, W.Altai
8,031 1-2 San Fernando salterns (Cádiz) 12,504
1 Bjurliu lake, Kazakhstan 18,946 9-10 Calpe
salterns (Alicante) 12,000 1 Urmia lake,
Iran 4,689 17 Bonmatí salterns (Alicante)
7,268 2-3 Ka lake, Inner Mongolia 10,931
5-6 Gerri salterns (Lleida) 12,319 1 Dong
Fang Hong salterns, China 8,920 1-2 Aveiro
salterns 18,105 2 Xiao Tan salterns,
China 16,570 5-6 Yingkou salterns,
China 5,920 1-2 AFRICA Madras salterns,
India 3,352 2-3 Walvis Bay,
Namibia 10,066 1 Wadi Natron, Egypt 4,947
1
15
Males
16

• Updating of cyst bank and database (1)
• The present cyst collection held at the IATS-CSIC
  contains about 280 samples 146 from Western
  Europe, 24 from Asia, 16 from Africa and 94 from
  the Americas.
• The updating of cyst bank is mainly focused now
  to the study of samples coming from countries
  neighbouring Spain, specially Portugal, France ,
  Italy and North Africa countries.
•  
• The biogeography and biodiversity of Artemia
  populations in Spain are well known (Amat et al.,
  1995), and changes about it were not expected,
  unless undue allochthonous species introduction.
• A similar situation was reported from Portugal
  and France since the early 80s. Narciso (1989)
  and Thiery Robert (1992) rendered preliminary
  information on the presence of A. franciscana
  populations in Portugal and France, respectively.

17

• Updating of cyst bank and database (2)
• Cyst samples from Portugal, France, Spain and
  Morocco, present in the IATS-CSIC bank, and
  collected between 1991 and 2002, produced A.
  franciscana populations .
• Preliminary research on Italian cyst samples
  (Tarquinia, Carloforte) are showing, up today,
  autochthonous Artemia populations (A. salina and
  A. parthenogenetica).
• The suspected absolute presence of A. franciscana
  in Portugal and France is endangering the
  biodiversity of Spanish autochthonous populations
  in the South of Spain (Cadiz and Huelva) at
  short-medium (?) term, and of the Mediterranean
  Spanish autochthonous populations at medium-long
  (?) term.
• Amat, F., Barata, C., Hontoria, F., Navarro,
  J.C., Varó, I. 1995. Int. J. Salt Lake Res., 3
  175-190.
• Narciso, L. 1989. EAS Special Publ., 10 183-184.
• Thiery, A. and Robert, F. 1992. Int. J. Salt
  Lake Res.,1 47-63.
•  

18
Females
19
Males
20
(No Transcript)