Figure. Dorsal view of Australiteuthis aldrichi, 21.3mm ML, mature male, holotype, preserved. Photograph by Wen-Sung Chung.
- Arm formula: III>IV>II>I.
- Arms with biserial suckers.
- Arm suckers in females normal.
- Arm suckers highly modified in mature males:
- Arm I - Proximal sucker small, distal 8 suckers larger (suckers 3 and 4 largest), arm-tip suckers very small.
- Arm II - Suckers nos. 6-8 greatly enlarged (ca. 4-5.4 times sucker no. 1).
- Arm III - Sucker no. 1 largest, suckers nos. 2-4 small, suckers 5-9 enlarged (ca. 2.5 times larger than sucker 2), more distal suckers normal.
- Arm IV (right) - Sucker no. 1 greatly enlarged (slightly larger than arm width), more distal suckers normal.
- Arm IV (left) - Hectcotylized, length variable, all suckers reduced to tiny swellings at tips of enlarged, conical-shaped sucker stalks.
- Inner rings of arm I suckers smooth; largest suckers of arms II and III with 5-7 low, broad truncate around entire margin of inner rings; large sucker of arm IV with smooth inner ring.
- Tentacular club with tetraserial armature.
- Marginal rows of suckers on manus on expanded protective membrane; sucker stalks arise distally from broad trabeculae.
- Distinct carpal cluster absent; carpal knobs absent.
- "Carpal" sucker rings with ca. 9 blunt, conical teeth on distal half, proximal half smooth.
- Large manal suckers with 14 sharply pointed conical teeth of distal 2/3, proximal 1/3 smooth.
- Buccal crown
- Buccal connectives attach to the ventral margins of arms IV.
- Buccal suckers absent.
- Head with long, narrow tentacular pocket.
- Eyes covered by cornea.
- Cornea without an eye pore.
- Secondary eyelid absent.
- Upper beak with deep notch at jaw angle and large tooth on shoulder; crest curved.
- Lower beak without lateral wall fold; cutting edge serrated; crest curved.
- Radula heterodont with rhachidian and first lateral teeth with three cusps; marginal plates present..
- Head free from mantle in nuchal region; nuchal cartilage well-developed.
- large brown chromatophores present on various parts of the Head and the anterior third of the dorsal mantle and the anterior half of the ventral mantle. Other regions including brachial crown, fins without chromatophores.
- Shell a gladius.
- At posterior extremity gladius curved ventrally over posterior visceral mass forming a cone-shaped structure.
- Mantle septum absent.
- Mature female with nidamental and accessory nidamental glands.
- Only left oviduct functional.
- Eggs relatively large, 1.5-1.75 mm by 0.96-1.32 mm.
- Accessory nidamental glands present.
Figure. Arms I and II of A. aldrichi, 17.3 mm ML, mature male, paratype. A - Oral and side views of left arm I. Drawing. a - Side view of left arm I. Photograph. b - Oral and side views of left arm II. Photograph. B - Oral and side views of left arm II. Drawing.
Figure. Arms I and II of A. aldrichi, 17.3 mm ML, mature male, paratype. A - Oral and side views of left arm III. Drawing. a - Oral and side views of left arm III. Photograph. b - Oral and side views of right arm IV. Photograph. B - Oral and side views of right arm IV. Drawing. Drawings and photographs from Lu (2005).
Figure. Hectocotylus (left arm IV) of A. aldrichi, 17.3 mm ML, mature male, paratype. Left - Oral and side views. Drawings from Lu (2005). Right - Side (top) and oral views. Photographs from Lu (2005).
Figure. Ventrolateral view of the head and brachial crown of A. aldrichi, 19.4 mm ML, male, showing the tentacle pocket. The squid had been lightly stained with methylene blue.
Figure. Left - Side view of upper and lower beak of A. aldrichi, 17.3 mm ML, mature male, paratype. Drawings from Lu (2005). Right - Oral lateral view of the lower beak. Photograph by Wen-Sung Chung.
Figure. Scanning electron micrograph of the radula of A. aldrichi, 22.7 mm ML, mature male. Photograph from Lu (2005).