الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
Abstract
Fourteen species of Egyptian snakes representing four different families (Colubridae, Elapidae, Viperidae and Boidae), belong to suborder: Serpents, order: Squarnata, class: Reptilia, were morphologically and cytogenetically studied.
The results of the chromosomal analysis were compared with those obtained from the classical methods in taxonomy using morphological and anatomical characters alone, the following is a summary of the results.
Class : Reptilia
order : Squamata.
Suborder : Serpentes (Ophidians; Snakes).
1) Family: colubridae
Eight species belong to family colubridae were cytogenetically studied .
A.) Two species of genus Psammophis, Psammophis schokari & P. sibilans were studied.
The two species of these snakes are living in different habitates . Psammophis schokari is living in sandy habitats, so it is characterized by sandy color from dorsal side and yellowish kvhite from ventral side; while P. silibans inhibite vegetated labitats, the body color is yellow from the ventral side and triated with yellow and green strands from the dorsal side. Moving very fast with very strong muscle.
The chromosomal analysis indicated that, although the two secies have the same diploid number of chromosomes 42 + ZW in females and 42 + ZZ in males. However the fundamental number was different in two species, it is 46 in the first and 60 in the second. Furthermore the karyotypes of the two species were distinctly different. In the case of Psammophis schokarL karyotype is composed of three groups, two pairs of autosomal metacentrics , nine pairs of autosomal telocentrics, ten pairs of micro chromosomes and a single or pair of sex chromosomes I which is ZW in female and ZZ in male respectively, where Z is metacentric and W is telocentric. On the other hand, the! karyotype of P. silibans was composed of four groups: one pair
of autosomal submetacentrics, six pairs of subtelocentric chromosomes, one pair of autosomal telocentrics , ten pairs OB microchromosomes and pair of sex chromosomes, Z is] subtelocentric and W is telocentric.
(B) Malpolon monspessulana & M. moilensis
They are prefer the north part of Egypt in sandy habitats, East and West desert and Siwa Oasis. The two species arel recognized by moderate size, the head distinct from the necLJ Malpolon monspesssulana is similar to M. moilensis but have green body color and small eyes. While M moilensis appear td be sandy, yellowish brown in body color with yellow spots,! and orange large eyes .
The chromosomal analysis of the two species indicated that, they both have the same haploid chromosome number of n = 20 -j ZW in females and n = 20 + ZZ in males, however the fundamental number was different in the two species (FN = 46 ii the female and FN = 60 in male ). Furthermore the karyotype of Malpolon monspessulanas is composed of four different groups^ two pairs of autosomal metacentrics, two submetacentrics of chromosomes, six pairs of telocentrics, and ten pairs ofj microchromosomes in addition to a single pair of sex chromosomes (ZW) in females and (ZZ) in males, where Z if metacentric and W is telocentric .
While they are arranged in four groups in M. moilensis as: Six pairs of metacentric chromosomes, three pairs of submetacentric chromosomes, one pair of telocentrics and ten pairs of microchromosomes in addition to one pair of sex chromosomes Z metacentric and W is submetacentric.
(C) Coluber nummifer & C.flomlentus
Although the two species are living in different habitats where C. nummifer is living in Cairo, Giza and in Sinai especially in Al Arish, C. florulentus is found in Upper Egypt in vegetated lands in Qena and Luxor. Coluber nummifer has creamy body color from the ventral side with dark scales on the third or the fourth ventral scale. On the other hand C florulentus has dark olive brown color with drake transverse strands and dark • spots.
The chromosomal analysis show that the two species have |the same haploid number of chromosomes 17 + ZW in females and 17 + ZZ in males. However the karyotypes of the two species were different. The karyotype of Coluber nummifer : is omposed of four groups, five pairs of metacentric chromosomes, one pair of submetacentric chromosomes, one pair of subtelocentrics and ten pairs of micro chromosomes together with a pair of sex chromosome where Z element is metacentric and W is submetacentric. In C. florulentus the chromosomes are arranged in three groups: five pairs of metacentric chromosomes, two pairs of subtelocentrics and ten pairs of microchromosomes together with a pair of sex chromosome which have Z element is pietacentric and W is submetacentric.
|D) Telescopus dhara
It is distributed in Wadi Feiran arid Wady El Notrun and Sinai. Head is oval distinct from the neck, size is moderate and the body color is reddish brown. Feeds on birds and bats.
The haploid chromosome number of this species is 18 + ZW in females and 18 + ZZ in males, arranged in four different groups: five pairs of metacentrics, one pair of submetacentric, onel pair of telocentric and eleven pairs of micro chromosomes inl addition to one pair of sex chromosomes Z is submetacentric and! W is telocentric.
(E) Natrix tessllata
Aquatic snake live in water, head is narrow and elongated. The body color varies from brown, green to olive, with fourj longitudinal dark blotches. It feeds on fishes and amphibians.
The chromosomal analysis of this species showed that th« haploid chromosome number is 17 + ZW in females and 17 + ZZ1 in males and (FN ) = 48. The chromosomes were arranged in two] groups: seven pairs of metacentrics and ten pairs oi micochromosomes together with metacentric Z chromosome and a submetacentric W.
2) Family: Elapidae
Naja haje & N.nigricollis
They are prefer vegetated lands, while Naja haje inhibit th desert regions N. nigricollis usually found in Upper Egvpt swimming in the river Nile especially in the winter, both species feeding on rodents, frogs and sometimes other snakes, m nagricollis can be distinguished from N. haje by the presence J black collar around the neck.
The chromosomal analysis of the two species indicated that they both have the same haploid number of n = 18 + ZW h females and n = 18 + ZZ in males . However the fundamental number was different in the two species (FN = 38 in femal and FN = 44 in male ). Furthermore the karyotype in the two species were distinctly different, the karyotype of Naja haje is composed of three different groups, one pair of autosomal metacentrics, six pairs of telocentric chromosomes and eleven pairs of microchromosomes and a pair of sex chromosomes (ZW ) in females and (ZZ) in males, Z is metacentric and W is submetacentric. On the other hand the karyotype of Naja nigricollis was composed of three groups also, but they are arranged in five pairs of metacentrics, five pairs of telocenrics and nine pairs of microchromosomes in addition to one pair of sex chromosome Z is submetscentric and W is subtelocenrtic.
(3) Family Viperidae
(A) Cerastes cerastes & C. viper a
These species inhibit desert and sandy regions, the color is yellow (sandy), the skin is rough. Head is large and distinct from the neck and triangular in shape, C. cerastes recognized by a pair of horns in the head.
As the cytogenetic findings: The two species have the same diploid number of chromosomes 2n = 34 + ZZ in male and 2n = 34 + ZW in female and the fundamental number was in two species (FN = 46 ). But the karyotypes of the two species were different. The karyotype of Cerastes cerastes is composed of three different groups: Sex pairs of autosomal metacentrics, one pair of autosomal telocentric and ten pairs of microchromosomes and a single or a pair of sex chromosome ZZ and ZW (in males and females) respectively . On the other hand, the karyotype of C. viper a was composed of five groups: Three pairs of autosomal metacentrics, two pairs of submetacentries, one pair of subtelocentric, one pair of telocentrics and ten pairs of microchromosomes in addition to one pair of sex chromosomes (ZW), where Z is metacentric and W is submetacentric.
(B) Echis carinatus
This, snake is living in sandy areas and Oasis, feeding on small mammals, lizards and birds. The body size is moderate, brown in color with dark spots.The head is triangular. This snake is represented the most dangerous snake.
The chromosomal analysis of Echis carinatus indicated that the diploid chromosome number is 2n = 34 + ZW in female and (FN) = 48, the chromosomes are arranged in four groups: Three pairs of metacentric chromosomes, two pairs of submetacentric chromosomes, two pairs of subtelocentric chromosomes and ten pairs of microchromosomes. Z sex chromosome is metacentric and W is submtacentric.
(4) Family: Boidae
Eryx jaculus
This species is found in the north of Sinai in Al Arish. members of this species recognized by heavy body which covered) with small scales . Feeding on Gekkonids.
The chromosomal analysis of this species showed that The diploid chromosome number is 2n = 36, (FN = 38). The chromosomes are arranged in three groups: four pairs oi metacentrics, four pairs of telocentric chromosomes and ten paii of microchromosomes. No sex chromosome heteromorphism evidence.
Table (16): Cytogenetic data of the present study.
! Taxa 2N FN Karyotype
Class :Reptilia
order :Squamata Family :Colubridae Psammophis schkari 2N=44 FN=46 2M., 9T., 20mic (ZM.,WA)
Psammophis sibilans Malpolon monspessulana 2N-44 2N=42 FN=60
FN=48 !M.,6ST.,lT.,26mic(ZST..WA) 2M., 2SM. 6T., 20mic (ZM..WA)
Malpolon moilensis 2N=42 FN=60 6M., 3SM., 1ST., 20 mic (ZM.,WSM)
Coluber nummifer 2N=36 FN=46 5M.,lSM..lT.,20raic(ZM.,WSM)
Coluber floridentus 2N=36 FN-48 5M. 2ST., 20mic (ZM.,WSM)
Telescopus dhara 2N=38 FN-48 5M.,1SM,.1T.,21 mic (ZSM.,WA)
Matrix tessllata 2N=36 FN=48 7M., 20mic (ZM..WSM)
Family:Elapidae Naja haje 2N=38 FN=38 1M., 6T., 21mic (ZM.,WSM)
Naja nigricollis 2N=38 FN=46 5M., 5T.18mic(ZST.,WA)
Family :Viperidae Cerastes cerastes 2N=36 FN=46 6M.JT.20 mic (ZM.,WA)
Cerastes vipera 2N-36 FN-46 3M.,2SM.,lST.lT.,20mic(ZM.,WSM)
Echis carinatus 2N=36 FN=48 3M., 2SM., 2ST.20 mic (ZM.,WSM)
FamilyrBoidae \Eryxjaculus 2N=36 FN=38 4M., 4T.20 mic.
2N = The diploid chromosome number, FN = The autosomal fundamental number, M = Metacentric, SM = Submetacentric, ST = Subtelocentric, T = Telocentric, mic = microchromosomes. Z, W = sex chromosomes.