Colossendeis megalonyx orcadense Fry & Hedgpeth 1969

“Colossendeis megalonyx orcadense n. comb. (Figs. 7, 8, 11-14, 22, 23)

MATERIAL EXAMINED

Through the kindness of Mr. Rodger Waterston and the authorities of the Royal Scottish Museum, we have been able to re-examine Hodgson's type specimen.

Eltanin Sta. 393, 1 male.

DESCRIPTION

Based on the type specimen and one additional male specimen, augmented by information in Hodgson's description and in Fage (1956) and Stock (1963). The holotype has been fixed with glue to an opaque glass plate, and therefore it was not possible to examine all of its structures.

EYES. Completely lacking, or if present, entirely un­pigmented.

OVIGERAL SPINE FIELDS: Ovigeral spine fields with the configuration

NS : (Sp / A) : (MF / B) : ((N/P) / (n=2))

RECORDED SIZE RANGES:

L. leg

110-126 mm

L. trunk

12-13 (?+)

L. probosci

18-20

L. palp

27.3-35.85

PERCENTAGE LENGTHS OF SEGMENTS:

Palp segments

Holotype

Madagascar

9^th

6.95

8.05 (-)

8^th

6.95

7.32 (-)

7^th

5.00

3.66 (-)

6^th

15.98

14.64 (-)

5^th

11.12

11.34 (-)

4^th

19.46

21.96 (-)

3^rd

3.61

?

2^nd

30.58

32.94 (-)

Leg

3 coxae

5.46

5.53

Femur

29.12

27.65

Tibia 1

33.67

23.70

Tibia 2

20.02

18.96

Tarsus

10.01

10.27

Propodus

6.37

6.71

Claw

4.55

6.71

RELATIVE PROPORTIONS (See also Figs. 7, 8, 11-14, and Table 2):

L. leg ÷ L. trunk

8.46

10.50

L. leg ÷ L. proboscis

5.50

7.00

L. leg ÷ L. palp

3.06

4.61 (-)

L. palp 4th ÷ L.

0.63

0.67

L. femur ÷ L. tibia 1

1.14

1.16

L. femur ÷ L. tibia 2

1.45

1.45

L. proboscis ÷ L. trunk

1.53

1.50

DEPTH RANGE AND DISTRIBUTION

The Madagascar and South African records extend by more than two thousand metres the greatest depth recorded for Colossendeis megalonyx. In view of the variable development of its eyes, it seems reasonable to suggest that this sub-species is primarily an abyssal form. Hodgson gave no depth for his specimen, although he refers to it as a "shallow water" form. Such an apparently wide bathymetric range is not as surprising as appears at first. C. angusta, which occupies an abyssal habitat in all major temperate and tropical ocean basins is found in the sub-littoral region of the Arctic (Stephensen, 1933).” (Fry & Hedgpeth 1969, p. 34-35)