Source: http://www.tolweb.org/Vitreledonella_richardi/20195
Timestamp: 2019-04-25 00:27:12+00:00

Document:
The Vitreledonellinae contains one species.
Little information exists on the biology or ecology of this pelagic octopod. It has a cosmopolitan distribution in tropical and subtropical waters where it lives at meso- to bathypelagic depths. The body is gelatinous, transparent and almost colourless. The peculiar long, narrow shape and position of the digestive gland is seen in the title photograph. The stomach and caecum, unlike most other octopods, is reportedly located anterior to the digestive gland. The photo, however, indicates that, in the living octopod, it actually lies on the dorsal surface of the transversely oriented digestive gland.
with left arm IV hectocotylized.
With retangular-shaped eyes in frontal view.
Suckers in single series, widely separated from one another.
Left arm III hectocotylized; spherical vesicle present near tip; other arms, in males, with suckers abruptly enlarged beyond web.
Figure. V. richardi, Hawaiian waters. Left - Side view of the tip of the hectocotylus which has.an unusual oval vesicle with a slender papilla at its tip. Right - Drawing the the octopod showing the hectocotylized left arm III. Photograph by R. Young, drawing from Hochberg, et al. 1992.
Eye: Strongly laterally compressed. Shape nearly rectangular in lateral view of octopod; eye width equal to lens diameter; ventral, blunt rostrum-like extension on eye with iridescent tissue.
Figure. V. richardi, Hawaiian waters. Left -Lateral view of head (frontal view of eye) showing the unusual shape of the eye. Right - Dorsal view of head showing long optic stalks. Photographs by R. Young.
Modified from S. Thore (1949).
Radula with multicuspid rhachidian (with a-seriation) and unicuspid first and second lateral teeth (= heteroglossan radula) (drawing on right).
Digestive gland long and slender, spindle-shaped.
Stomach dorsal to digestive gland.
A list of all nominal genera and species in the Vitreledonellinae can be found here. The list includes the current status and type species of all genera, and the current status, type repository and type locality of all species and all pertinent references.
Figure. These pictures are from a video sequence taken from a submersible at about 900 m depth off Hawaii. A Vitreledonella drifted into view but clearly has too many arms. A closer look indicates that one octopus is within the web of another; presumably they are mating. Unfortunately, the hectocotylus cannot be identified. Photographs from Young, et al., 1999.
The females apparently brood their eggs within the mantle cavity until hatching since Joubin (1937) captured numerous hatchlings with a mature female.
Figure. Hatchings of V. richardi, hatchlings. Left - Dorsal view 2.5 mm ML. Right - Side view, 2.2 mm ML. Drawings from Joubin, 1937, via Hochberg et al., 1992.
side view. Frame grab from video.
V. richardi maintains the digestive gland in a vertical orientation as it swims. The slender shape of this opaque organ and its vertical orientation will result in the otherwise transparent octopod casting a minimal shadow. Concealment is important when the octopod is at the upper end of its habitat where the downwelling light is dim but strongly directional. A video clip of this animal showing the vertical orientation of the digestive gland is available at Cephalopods in Action.
The best vertical distribution data is from the eastern North Atlantic. Until about 40 mm ML, most captures have been in the upper 300 m. The larger octopods have a very broad vertical distribution with most captures occuring in the upper mesopelagic zone but with some at lower mesopelagic depths during both the day and night. At night two captures were made in the lower regions of the epipelagic zone (Clarke and Lu, 1975 and Lu and Clarke, 1975).
Figure. Vertical distribution of V. richardi. All captures were made with opening/closing trawls. Bars represent a capture and the bar length indicates the depth range of the trawl while open. Yellow bars indicate a daytime capture and blue bars a nighttime capture. Graph modified and redrawn from Clarke and Lu, 1975 and Lu and Clarke, 1975.
The geographical distribution of V. richardi is throughout the tropical and subtropical regions of the world's oceans (Nesis, 1982).
Clarke, M. R. and C. C. Lu. 1975. Vertical Distribution of cephalopods at 18 N 25 W in the North Atlantic. Journal of the Marine Biological Association of the United Kingdom, 55 (1): 165-182.
Joubin, L. 1918. Etudes preliminaires sur les cephalopodes recueillis au cours des croisieres de S.A.S. le Prince de Monaco, 6e Note: Vitreledonella richardi Joubin. Bull. Inst. Oceanogr. Monaco 340: 1-40.
Joubin, L. 1937. Les octopodes de la croisiere du "Dana" 1921-22. Dana Report, 11: 1-49.
Lu, C. C. and M. R. Clarke, 1975. Vertical Distribution of cephalopods at 11 N 20 W in the North Atlantic. Journal of the Marine Biological Association of the United Kingdom, 55 (2): 369-389.
Roper, C. F. E., R. E. Young and G. L. Voss (1969). An illustrated key to the families of the order Teuthoidea. Smiths. contr. zool., 13:1-32.
Young, R. E., M. Vecchione and D. Donovan. 1999. The evolution of coleoid cephalopods and their present biodiversity and ecology. South African Jour. Mar. Sci..
Page: Tree of Life Vitreledonellinae Robson 1932. Vitreledonella richardi Joubin 1918. The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.

References: V. 
 V. 
 V. 

V. 
 V. 
 V.