Evolution of the hectocotylus in Sepiolinae (Cephalopoda: Sepiolidae) and description of four new genera
Author
Bello, Giambattista
text
European Journal of Taxonomy
2020
2020-05-29
655
1
53
journal article
21713
10.5852/ejt.2020.655
fadee126-7da7-47d9-b9ac-973697ecf9f5
2118-9773
3888797
0042EFAE-2E4F-444B-AFB9-E321D16116E8
Rondeletiola
Naef, 1921
Figs 16–17
Rondeletiola
Naef, 1921: 536
.
Type
species
Sepietta minor
Naef, 1912
, by monotypy.
Diagnosis
Sepiolinae
with fins bluntly angled laterally; their length about half mantle length. Suckers biseriate on all arms. Tentacle club suckers in 16 longitudinal rows. Mantle-head occipital band narrow (not reaching over the ocular globes). Ventral mantle margin slightly sinuate, without any deep funnel indentation. Gladius absent. Unpaired visceral photophore on ventral surface of ink sac, slightly oval, clearly derived from paired light organs joined in sagittal plane. Hectocotylus (male left arm I) tripartite: basal part with three suckers, two ventral and one dorsal; copulatory apparatus with transverse formation of two ventral and two dorsal modified suckerless pedicels all four of them fused at their bases, ventral-most strongly developed hook-like, others hardly developed, dorsal pedicels forming most part of transverse crest; distal part lacking first two ventral suckers, some proximal suckers enlarged in both rows. Female bursa copulatrix roughly ear-shaped, devoid of cover.
Included species
Rondeletiola minor
(Naef, 1912)
and
R
.
capensis
(Voss, 1962)
.
Remarks
This genus is widely distributed from the NE Atlantic and Mediterranean, throughout the E Atlantic, to the South African part of the Indian Ocean. It is characterized among the sepiolines of this area by its unique visceral light organ, that differs from that of
Boletzkyola
gen. nov.
(compare with the description of the latter genus).
Rondeletiola
is sister genus to
Sepietta
(Bello 1998)
. The species
Inioteuthis capensis
is re-assigned to
Rondeletiola
fide
Vecchione & Young (2004)
and Reid (pers. com.).