Species c. C. decorus group


Male:  The adult male is a typical member of the C. decorus-group.

Male terminalia of C. species c.
A typical C. decorus-type hypopygium.

About 13 setae in multiple associated pale patches on TIX, Superior volsella of E-type closest to Strenzke's figure g, i.e. longer than most decorus-group species. Anal point relatively broad with approximately parallel sides.  Inferior volsella slightly longer than the anal point and to about the mid-point of the gonostylus which narrows markedly over the distal third.

Pupa: The pupa is typical of most of the species in the C. decorus-group, in lacking the secondary tubercle on the cephalic tubercles found in C. decorus itself.  The caudolateral spur has about 4 spines.

Larva of the semireductus-type with moderately long tubules (abt. 1.2 times segment width), on average of equal length (anterior 0.7-1.84 mm; posterior 0.6 - 1.84).  Larval length, females 9.0-14.1; males 9.5-12.3 mm).  Lateral tubules relatively short (30-250 micron).  Anal tubules about 3-5.5 times longer than wide, dorsal pair usually slightly longer with a medial constriction about a third from the base.
Gular region darkened over most of central region, frontoclypeus pale.  Distance between antennal bases sometimes greater, but more usually less, than distance between the S4 setae.
Mentum (Fig. c) with pointed teeth, c2 teeth partly separated from the square sided c1 tooth (type III or sometimes IB); 4th laterals partly reduced, sometimes to level of 5th laterals (type I-II).
Ventromental plates (Fig. d) separated by 0.38 of mentum width (IPD), with about 31-40 striae, VMR about 0.23-0.28.  Pecten epipharyngis (Fig. a) with about 11-16 sharp pointed teeth.
Premandible with teeth about equally long, outer about 2.5-3 times wider than inner tooth.

Antenna (Fig. b) with basal segment 0.3-0.4 of ventral head length; AR abt. 1.65-2.1; basal segment about 3.0-3.6 times as long as wide; A4/A3 about 1.4-2.5; relative lengths antennal segments (micron) 119 ; 27 : 7 : 12 : 7.
Mandible (Fig. e) with the third inner tooth slightly colored and not separated (type IA or B) and about 14-17 furrows on outer surface near base; pecten mandibularis with about 11 bristles.

Cytology:  4 polytene chromosomes with thummi arm combination AB, CD, EF, G, these arm combinations difficult to identify.
Arm G normally paired although sometimes unpaired up to the clearly subterminal nucleolus; Balbiani rings present but often difficult to see.    No other nucleoli?
Bands 22 - 24 of arm B in usual position next to the centromere.
Quite polymorphic, including in arms A, D and F, and sometimes with complex inversions.
The inv4-11b in arm E suggests a connection to C. quinnitukqut
Arm A1:   
Arm B1:   
Arm C1:   
Arm D1:   
Arm E1:    1 - 3a, 5 - 10b, 11b - 10c, 3f - 4, 11c - 13
Arm F1:   

            Farm pools and pools in rivers.

Found: Ontario – Copanspin Farm, Dunrobin (45.45°N, 76.00°W); Carlingwood, Ottawa (45.37°N, 76.00°W); Rideau River, Black Rapids (45.32°N, 75.82°W)
            (all Carleton Co.); Vittoria, Norfolk Co.
            Florida – Lake Ruby, Winter Haven.
            Vermont – White River, Sharon (43.80°N, 72.45°W), Windsor Co.

See also    C. bifurcatus,    C. sp. b,    C. sp. j,    C. sp. 2a,    C. 'proulxi',    C. 'butleri",    C. sp. 2t,    C. decorus Joh.,    C. sp. 3h,    C. sp. 3i,    C. sp. 3j,    C. sp. 3r,    C. harpi,    C. blaylocki,    C. mozleyi,    C. winnelli.

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Modified: 22 June 2021
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