C. magnivalva Kieffer, 1917, immatures

Fourth instar larva: a medium sized plumosus-type larva.  Length (females) about 19.7 (11.3-14.5) mm.  Anterior ventral tubules (1.48 (0.92-2.36) mm.) slightly shorter than the posterior pair (1.54 (1.08-2.48) mm.); lateral projections 272.5 (200-360) µm long.  Anal tubules about 380 (220-480) µm long and about twice as long as wide.
Gular region at least slightly darkened on posterior half, frontoclypeus also darkened to some extent, sometimes just along the edges.  Oesophageal opening (Fig. c) 76.5 (61-88) µm wide and 4.53 (3.50-5.33) times wider than deep.
Mentum (Fig. e) with 4th laterals only slightly reduced (essentially type I), and c2 teeth only partly separated from c1 (type IA), 6th laterals arising at a slightly lower level.
Ventromentum (Fig. f) about 168.13 (161-180) µm wide and 3.38 (3.18-3.65) times wider than deep; about 1.09 (1.03-1.18) times wider than the mentum and separated by about 31-39% of mentum width; with about 34.25 (28-38) striae; VMR 0.26 (0.21-0.32).
Premandible (Fig. d) of type B2, with inner tooth about 4.4 times wider thean the outer tooth, with both coming to a sharp point when not worn.  Pecten epipharyngis (Fig. a) with about 16 (14-17) usually type B teeth.
Antenna (Fig. b) with basal segment only about a third of the VHL, but relatively long compared to the other antennal segments, about 3.52 (3.17-3.83) times longer than wide; AR about 1.93 (1.77-2.19); proportions (micron) 110 ; 27 ; 9.5 ; 12 ; 6.5.
Distance between the antennal bases (124-144 µm) greater than that between the S4 setae (121-126.5 µm), which are separated by about 74-76% of the frontoclypeus width at that point; S5 setae slightly posterior to the nearby RO.Mandible (Fig. g) about 220 (212-230) µm long; with 3rd inner teeth showing some colour and usually only partly separated (type IA-IIIB); about 16.6 (15-18) furrows near the base, and about 16.6 (15-18) furrows near the base and about 11.8 (11-13) taeniae in the Pecten mandibularis.

Cytology:  4 polytene chromosomes with the pseudothummi arm combination AE, BF, CD, G.
Arm G closely paired with a small nucleolus near the middle of the arm, and three Balbiani rings (BRs), two just distal to the nucleolus and the other near the somewhat heterochromatic centromere.  The most distal BR is not always developed.
Nucleolus in arm F at about group 19.  No polymorphism known in Australian samples.
Irradiation experiments suggest the MD may be on either arm B or on chromosome CD.
magA1:    1 - 2c, 3 - 2d, 10 - 12, 14 - 13, 4 - 9, 15 - 19                                                  as crassiforceps
magB1:    A puff with some dark bands on distal side, may be developed near the distal end of the arm
magE1:    1 - 3e, 5 - 10b, 4 - 3f, 10c - 13                                                                  i.e. as cingulatus, etc.
magF1:    1 - 2a, 10d-a, 2b - 9, 11 - 23                                                                              as crassiforceps
magG1:    Nucleolus and at least one BRs near centre of the arm.    Site of BR4 just proximal to NOR, and further BR subterminal.

Specimens identified as C. magnivalva in Australia, Fiji and Tahiti, differ from those identified as C. crassiforceps from Japan by a fixed inversion in arm E and more complex changes in arm G.

Pupa:  Colour yellowish brown, muscle scars slightly darker; shagreen complete on tergites II-VII, anterior quarter on TVIII, none on TIX.  Length about 6.55 (6.3-6.8) mm (female) and 6.33 (5.04-6.7) mm (male); posterior margin of wingcase about 1.44 (1.4-1.5) µm (female), about 1.34 (1.1-1.5) µm (male); female antennal sheath about 450 (340-550) µm.  Cephalic tubercles 57.3 (51-71) µm (female), 71.0 (56-83) µm (male) long and usually wider than long in females but longer than wide in males; some slight indication of a secondary tubercle, also a small tubercle about 21.4 (15-28) µm long and 1.0-2.2 times longer than wide, just anterior to the respiratory scar.  Respiratory base 109-159 µm long and 46-66 µm wide, respiratory fibres narrowing in middle, HR 2.45 (2.1-2.7).
About 87 (55-105) recurved spines on second segment, occupying just over half of the segment width (subject to mounting distortion).  Pedes spurii B difficult to see on available specimens and only determined for segment II; pedes spurii A on segment IV about 116-158 µm long and about 0.22 (0.13-0.27) of segment length.  L-setae at III/IV margin at least 50-106 ┬Ám long and at IV/V margin at least 71-96 µm long. Spurs dark yellow brown, with about 1-3 spines plus 1-3 small spines in many cases where there is only 1 large spine.  Taeniae on anal fin in up to 3 rows towards the posterior end; about 53-115 taeniae but more in females (mean 96.7) than in males (mean 79.3).

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Modified: 24 October 2022
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