Sepiola Leach, 1817

Bello, Giambattista, 2020, Evolution of the hectocotylus in Sepiolinae (Cephalopoda: Sepiolidae) and description of four new genera, European Journal of Taxonomy 655 (655), pp. 1-53 : 35-36

Sepiola Leach, 1817

Figs 8B , 19–20

Sepiola Leach, 1817: 137 .

Type species

Sepiola rondeletii Leach, 1817 , by monotypy.

Diagnosis

Sepiolinae with fins rounded; their length about half mantle length. Suckers biseriate on arms I to III and at least proximally on arm IV. Tentacle club suckers in 4 to 8 longitudinal rows. Mantle-head occipital band narrow (not reaching over the ocular globes). A pair of kidney-shaped photophores on ventral surface of ink-sac. Gladius present, reduced. Ventral mantle margin slightly sinuate, without any deep funnel indentation. 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 lengthened and fused with each other throughout their length (few additional dorsal modified pedicels may be present mesially to transverse formation); distal part with some enlarged suckers in dorsal row. Female bursa copulatrix roughly ear-shaped, devoid of cover.

Included species

Sepiola rondeletii Leach, 1817 , S. affinis Naef, 1912 , S. atlantica d’Orbigny, 1842 , S. boletzkyi Bello & Salman, 2015 , S. bursadhaesa Bello, 2013 , S. intermedia Naef, 1912 , S. robusta Naef, 1912 , S. steenstrupiana Levy, 1912 and S. tridens de Heij & Goud, 2010 .

Remarks

The revised diagnosis of the genus Sepiola reported above was formulated to comply with the rearrangement of Sepiolinae according to the present results. It dismisses several species previously included in Sepiola , namely S. aurantiaca , S. birostrata , S. knudseni , S. ligulata , S. pfefferi and S. trirostrata , which are better placed in different genera. The revised genus Sepiola includes all the species in the Sepiola atlantica -group sensu Naef 1923 (see also Bello 2013; Bello & Salman 2015). Hence, the atlantica -group coincides with the genus Sepiola as revised in this paper.

The overall distribution of these species ranges from the north-eastern Atlantic Ocean to the Mediterranean Sea.

Figures

Fig. 8. Basic types of bursae copulatrices in Sepiolinae Leach, 1817 (highlighted by white frames). A. Closed type, plesiomorphic condition; mated female displaying a bunch of spermatophores inserted in the bursa copulatrix and peeping out its opening (arrow) (Sepiola birostrata Sasaki, 1918). B. Open type, apomorphic condition; virgin female (Sepiola boletzkyi Bello & Salman 2015). Scale bars: 1 mm.

Fig. 19. Hectocotylus of Sepiola boletzkyi Bello & Salman, 2015; a–b and c–d = modified ventral and dorsal pedicels, respectively, forming the copulatory apparatus proper; * = lobe in the dorsal sucker row; 1–11 = heteromorphous suckers in the dorsal row of distal part. A. Hectocotylus, oral-lateral view. B. Copulatory apparatus, mesial view. C. Copulatory apparatus, oblique mesial view. Scale bars: 1 mm (after Bello & Salman 2015).

Fig. 20. Hectocotylus of Sepiola bursadhaesa Bello, 2013; mesial view. The square bracket encompasses the groove in the mesial lateral side (the arm in the foreground is the first right one). Scale bar: 2 mm.