Fig 1.
Mitotic karyotype of A. fraterculus.
(A, B, D) female; (C, E) male. (A, B, C) Giemsa staining; (D, E) C-banding. The sex chromosomes, X and Y, are shown. The acrocentric nature of the chromosomes is evident in (B).
Fig 2.
Heterochromatic network (hn) representing the under-replicated sex chromosomes.
The heterochromatic network (hn) is indicated. Selected telomeres and centromeres are marked in the two nuclei.
Fig 3.
Centromeric regions of A. fraterculus polytene chromosomes.
(A) Centromeres of chromosomes II and III, (B) a partial chromocenter involving chromosomes III and V, (C) a partial chromocenter involving three chromosomes, II, III and V. Arrows indicate the heterochromatic threads in (A). C indicates the centromere.
Fig 4.
Ectopic pairing between telomeres of A. fraterculus polytene chromosomes.
(A) a three-way pairing between telomeres of chromosomes III, V and VI, (B) II and III chromosomes, (C) IV and VI chromosomes.
Fig 5.
Photographic map of the A. fraterculus (A.sp.1) salivary gland polytene chromosome II (sections 1–22).
C indicates the centromere.
Fig 6.
Photographic map of the A. fraterculus (A.sp.1) salivary gland polytene chromosome III (sections 23–44).
C indicates the centromere.
Fig 7.
Photographic map of the A. fraterculus (A.sp.1) salivary gland polytene chromosome IV (sections 45–64).
C indicates the centromere.
Fig 8.
Photographic map of the A. fraterculus (A.sp.1) salivary gland polytene chromosome V (sections 65–84).
Asterisks indicate an alternative appearance of chromosomal region 81–84, due to differences in puffing pattern. C indicates the centromere.
Fig 9.
Photographic map of the A. fraterculus (A.sp.1) salivary gland polytene chromosome VI (sections 85–100).
C indicates the centromere.
Fig 10.
A polytene nucleus of A. fraterculus. Characteristic landmarks of different polytene chromosome arms are shown.
Sections 17, 40–42, 45–49 and 65–69 are indicated. Four of the five telomeres (III, IV, V, VI) and two of the five centromeres (IIC, IIIC) are also noted.
Fig 11.
A polytene nucleus of A. fraterculus. Characteristic landmarks of different polytene chromosome arms are shown.
Sections 17–18 and 91–92 are indicated. The five telomeres (II, III, IV, V, VI) and two of the five centromeres (IIC, IVC) are also noted.
Fig 12.
A polytene nucleus of A. fraterculus. Characteristic landmarks of different polytene chromosome arms are shown.
Sections 40–42, 50–53 and 91–92 are indicated. II and VI telomeres are indicated.
Fig 13.
Comparison between A. fraterculus (A. f) and A. ludens (A. l) polytene chromosome maps.
Lines connecting the chromosomes indicate sections with similar banding pattern and horizontal arrows show the relative orientation between them. C indicates the centromere. Asterisks indicate the transposition of a specific region between the two species.