“Colossendeis megalonyx megalonyx n. comb. (Figs. 7, 8, 11-16, 23)
MATERIAL EXAMINED
NZOI Sta. A 459, 3 males, 3 females, 1 juvenile; Sta. A 461, 21 males; Sta. A 464, 1 female; Sta. A 468, 2 females; Sta. A 469, 1 juvenile; Sta. A 471, 1 female.
Trans-Antarctic (N.Z.) Sta. 4, 1 male; Sta. 6, 1 female, 1 juvenile; Sta. 75, 1 male; Sta. 79, 1 male, 1 female; Sta. 100, 1 juvenile.
Dominion Museum (N.Z.) Sta. McMurdo Sound (Fishtrap) 1 male. Edisto Sta. 8 (ED-8), 1 juvenile; Northwind Sta. 5, 1 male, 2 females; Burton Island Sta. 16, 1 ?male.
Stanford Sta. GLD-4, 1 male; Sta. GLD-5, 1 juvenile; Sta. GLD-7, 1 juvenile; Sta. GLD-10, 2 Se; Sta. GLD-13, 2 juveniles; Sta. GLD-16, 1 female; Sta. A, 1 female; Sta. B, 2 females; Sta. F, 2 females, 1 juvenile; Sta. S, 1 male; Sta. W, 1 male, 1 female; Sta. X, 1 male, 1 female; Sta. 60A, 1 male; Sta. 61B, 1 ?male.
Kainan Bay, 1 juvenile.
Eltanin Sta. 268, 2? soft; Sta. 353, 1?; Sta. 376, 1 S; Sta. 393, 1?; Sta. 410, 10SS, 9 99, 2 indeterminate, 1 juvenile; Sta. 413, 3 SS; Sta. 418, 1 S; Sta. 423, 1 ?; Sta. 437, 5 3'3', 8 99, 5 indeterminate; Sta. 411, 1 S; Sta. 445, 4 SS, 1 9; Sta. 534, 1 9, 1 juvenile; Sta. 538, 2 SS, 6 99, 1 indeterminate; Sta. 545, 1 S, 3 99; Sta. 558, 1 3', 19; Sta. 608, 1 S; Sta. 686, 2 99; Sta. 691, 1 juvenile; Sta. 709, 1 indeterminate; Sta. 723, 1 3?, 1 9.
Vema Sta. 17-99, 1 S, 2 indeterminate, 1 fragmentary; Sta. 17-100, 1 9?; Sta. 17-101, 2 SS, 1 9.
B.M. (N.H.) Regn. No. 1933.3.23.30-6; 1933.3.23.21-6;
1907.6.24.108-17 (Types of C. frigida); 1956.10.10.421; 1915.7.2.24.8-27; 1933.3.23.27-9; 1933.3.23.37-9; 1942.12.30.3; 1915.7.24.6; 81.38 (Types of C. megalonyx); 1907.6.24.118 (Holotype of C. rugosa); 1915.7.24.7; Unregistered: Discovery Sta. 1948; Discovery Sta. 1952.
DESCRIPTION
Based on 187 adult and 23 juvenile specimens, augmented by data from earlier works.
SIZE RANGES EXAMINED:
Juveniles
Adults
L. trunk
3.72 - 6.40 mm
5.73 - 12.90 mm
L. proboscis
5 .60 - 14.60
10.25 - 27.50
L. palp
5.41 - 21.88
15.73 - 41.10
L. leg
22 .80 - 55.20
54.10 - 149.00
PROPORTIONS palp segments (as percentage of terminal 8 segments):
Range
9th
5.55 - 10.23
8th
4.92 - 9.75
7th
1.94 - 11.51
6th
9.09 - 12.61
5th
6 .53 - 9.73
4th
19.69 - 28.12
3rd
2.46 - 5.13
2nd
21.97 - 41.43
Leg segments (as percentage of total leg length)
Range
3 coxae
3 .87 - 9.56
Femur
19.46 - 28.50
Tibia 1
20.54 - 25.43
Tibia 2
18.64 - 23.92
Tarsus
8.08 - 13.73
Propodus
6.17 - 10.61
Claw
2.94 - 7.73
RELATIVE PROPORTIONS:
L. palp ÷ L. proboscis
0.96 - 1.91
L. palp ÷ L. trunk
0.85 - 3.34
L. leg. ÷ L. proboscis
3.99 - 6.68
L. leg ÷ L. palp
3.21 - 4.56
L. leg ÷ L. trunk
3.49 - 13.02
L. proboscis ÷ L. trunk
0.87 - 2.48
L. femur ÷ L. tibia 1
0.80 - 1.24
L. femur ÷ L. tibia 2
0.80 - 1.47
L. tarsus ÷ L. propodus
1.13 - 1.86
L. claw ÷ L. propodus
0.40 - 0.87
L. 4th palp segt. ÷ L. 2nd palp segt.
0.55 - 0.90
RELATIVE GROWTH: Data on relative growth of certain structures are depicted in Figs. 11-14, 17-20; the parameters there illustrated are given in algebraic form in Table 2.
ABNORMALITIES OF THE PALP: In five specimens of C. m. megalonyx, one or other palp is aberrant, having eight instead of nine segments (Table 4). A similar condition has been noted (Calman, 1915, footnote to p. 26) in Colossendeis lilliei, and it also appears in Decolopoda. This might appear to be a very trivial feature, except that it enables us to recognise that some of the terminal palp segments form a unit and apparently react together to certain morphogenetic factors.
Superficially, a palp with one segment less than the normal could be the result of partially completed regeneration processes or their disturbance, or of a disturbance of the normal initial growth pattern of the palps.
The two immature specimens of Colossendeis discussed (p. 51) and figured (Figs. 72-74) indicate that the growth pattern of the palps in this genus is more complicated than that described by Sanchez (1959, pp. 39-45) for Nymphon gracile and Achelia echinata. In the specimen from Trans-Antarctic (NZ) Sta. 1, the articulation between the 3rd and 4th definitive segments is not fully formed, even though the palp is composed of eight clearly articulated segments.
In the five specimens which have a "wrong" number of segments in one palp, the relative lengths of the four terminal segments are unaffected, except in (1), where the 9th segment simply appears to be missing. In the other four, the totals of the four terminal segments are approximately equal for both right and left palp.
Whatever the initial cause of there being one articulation less in the palps of these specimens, the evidence suggests that the four terminal segments react together as a unit in longitudinal growth. Segmentation of this unit is apparently controlled by another factor or factors.
(1) GLD 10 male
(2) A 456 No. 21 female
Segments
Right
Left
Right
Left
9th
..
}
} 23.78
}
}
7.28
}
} 28.21
}
}
..
}
} 29.05
}
}
5.77
}
} 29.05
}
}
8th
8.11
7.06
10.00
6.58
7th
3.78
3.65
7.19
5.11
6th
11.89
10.22
14.39
11.59
5th
8.38
9.73
7.19
7.23
4th
27.57
25.79
23.80
24.59
3rd
4.05
3.65
2.87
3.64
2nd
36.22
32.60
34.46
35.52
Total L.
37.0 mm
41.10 mm
18.47 mm
18.39 mm
(3) A 459 No. 25 male
(4) A 459 No. 25 female
Segments
Right
Left
Right
Left
9th
..
}
} 27.60
}
}
8.15
}
} 27.47
}
}
8.22
}
} 29.59
}
}
..
}
} 28.77
}
}
8th
9.00
6.34
6.30
8.46
7th
6.60
3.32
4.11
6.77
6th
12.00
9.66
10.96
13.54
5th
7.50
7.25
7.95
7.33
4th
25.20
24.16
24.39
23.97
3rd
3.00
3.32
2.74
3.10
2nd
36.60
37.75
35.53
36.66
Total L.
33.03 mm
33.10 mm
36.50 mm
35.40 mm
(5) A 461 female
Segments
Right
Left
9th
...
}
} 27.43
}
}
8.20
}
} 29.00
}
}
8th
6.41
6.45
7th
7.59
3.22
6th
13.43
11.13
5th
8.74
8.79
4th
27.44
23.44
3rd
4.08
2.93
2nd
32.13
35.75
Total L.
32.74
34.10
“ (Fry & Hedgpeth 1969, p. 30-32)
