Family AUSTRODECIDAE Stock, 1954
Introduction
Austrodecus and Pantopipetta form a monophyletic Austrodecidae within an early derived clade close to Colossendeidae and Pycnogonidae (Arango & Wheeler 2007). All three are characterised by the absence of adult chelifores.
Previously, genera in Austrodecidae were assigned to Ammotheidae based on morphological characters (Arango 2002). However, Austrodecidae is a very peculiar lineage with highly specialised proboscis and mouth. Members bear a unique down-curved pipette-like annulate proboscis with a ventrodistal mouth which are bilaterally symmetrical, not tripartite as in the rest of Pycnogonida.
Little is known about the biology, especially the reproductive behaviour of Austrodecidae. No males carrying eggs or larvae have been found, a feature they share with Colossendeidae.
A very good biogeographic study of Austrodecidae is available in Stock (1957).
Diagnosis
Size small to tiny, attenuate; proboscis a slender tube with distal annulations except at the most basal portion; chelifores missing in adults; palps 4 or 5-segmented; ovigers 1-6 segmented: non-functional and without strigilis (in Austrodecus), or fully functional , 10-segmented, with strigilis in Pantopipetta. Femoral cement glands with single ventral outlet.
General References
Arango C.P. & Wheeler W.C. 2007. Phylogeny of the sea spiders (Arthropoda; Pycnogonida) based on Direct Optimization of six loci and morphology. Cladistics 23: 255-293
Arango, C.P. 2002. Morphological phylogenetics of the sea spiders (Arthropoda: Pycnogonida). Organisms, Diversity and Evolution 2: 107-125
Stock, J.H. 1954. Papers from Dr. Th. Mortensen's Pacific expedition 1914-1916. LXXVII. Pycnogonida from Indo-West-Pacific, Australian, and New-Zealand waters. Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening 116(1): 1-168
Stock, J.H. 1957. The Pycnogonid Family Austrodecidae. Beaufortia 6(68): 1-81