C. duplex Walker

Larva:    Large bathophilus-type larva.    Length 15.9 - 21.2 mm (female); 14.7 - 18.8 mm (male); ventral tubules, anterior 1.40 - 2.70, posterior 1.52 - 2.75 mm.    Head capsule heavily darkened on the gula, frontoclypeus and other regions.    Mentum with pointed teeth, particularly on central trifid tooth, which is type II.    Premandible with the inner tooth about 5x the width of the outer tooth.    AR about 2.4 (2.0 - 2.8); basal segment 3.0 - 3.4 times as long as wide; ring organ between a quarter and halfway up the basal segment; antennal proportions (µm): 170 : 33 : 8 : 15 : 8 .    Mandible with a distinct, sharp and fully separated third inner tooth (type III); about 14 - 16 striations near base.    Anal tubules relatively short and rounded (about 380-530 x 250-330 µm)

Cytology:    3 pairs of chromosomes with the modified pseudothummi arm combination AEG, BF, CD.    Arm G with medial nucleolus, with adjacent BR and other BRs more proximal.    Other nucleoli in arms A, C and F. Polymorphism in arms A, B (often sex linked), D, G, and F.
dupA1:    1a-e, 4c-a, 12a-c, 3i-f, 9 - 8a, 2d - 3e, 1f - 2c, 10a - 11, 4d - 7, 13a - 19
dupA2:    an overlapping inversion or transposition.
dupB1:    Puff and proximal dark bands (groups 7-8) about middle of arm as in oppositus and australis
dupB2:    Puff separated from dark bands to near tip of arm by an inversion and transposition.
dupC1:    nucleolus about one third from centromere.
dupD1:    1 - 2, 16 - 10d, 3 - 10c, 17 - 24
dupD2:    1 - 2c, 17c - a, 10c - 3, 10d - 16, 2h-d, 17d - 24
dupD3:    1 - 2c, 8 - 10c, 17a-c, 7 - 3, 10d - 16, 2h-d, 17d - 24
dupE1:    see Wülker et al. (1989), but also contains inversion 1 - 6 into arm G.
dupF1:    1 - 2a, 10 - 2b, 11 - 23                                            as oppositus F1

Click here for the polytene chromosomes

Larva morphologically very similar to those of C. australis and C. occidentalis.    Separable from the former by the difference in chromosome number, and from the latter by eastern distribution.

Pupa:    Various characters are given in the Table below.    Spurs with about 10 spines, ranging from 4 - 16.

 

 

Females

 

Males

 

Mean

Range

Mean

Range

Length (mm)

12.89

10.98 – 15.28

11.94

7.8 - 14.0

Inner margin wing case (mm)

2.64

2.32 - 3.12

2.46

1.84 - 2.92

Cephalic tubercles (µm)

 

 

 

 

Cephalic bristles (µm)

 

 

 

 

Recurved hooks on abd. seg. 2

84

74 - 98

71

55 - 84

Swim fin taeniae (one side)

254

128 - 350

225

198 - 292

The pupa of C. duplex can be readily distinguished from those of C. australis and C. occidentalis by the spur in which the spines are spread, rather than closely applied, as in the other two species.    There also tend to be fewer recurved hooks on segment 2 than in C. australis, but there is considerable overlap.

The polytene chromosomes were initially described by Martin (1971) and later, with preliminary phywsical maps, by Martin et al. (2008).    Nucleoli and location of C-bands were studied by Lentzios & Stocker (1979) and Lentzios et al. (1980).

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Modified: 11 March 2009
Access: Unrestricted
Copyright © 2005-2009, Jon Martin.