Fecundity of the common cuttlefish, Sepia officinalis L. (Cephalopoda, Sepiida): a new look at the old problem

The potential fecundity (PF) of advanced maturing and mature pre-spawning cuttlefish S. officinalis in the Aegean Sea varies from 3,700 to 8,000 (mean 5,871) oocytes, whereas the number of large yolk oocytes increases with mantle length from 130 to 839. Small oocytes predominate at all maturity stages. Spawning animals have a PF of some 1,000-3,000 eggs below that of pre-spawning females. This shows that intermittent spawning, which occurs in captivity, is a normal process in natural habitats. Empty follicular sheaths are resorbed very rapidly, and their number does not represent the number of eggs laid by the female prior to sampling. Regulative oocyte resorption was observed at early maturation in some cuttlefishes

Reproduction in Heteroteuthis dispar (Rüppell, 1844) (Mollusca: Cephalopoda): a sepiolid reproductive adaptation to an oceanic lifestyle

Small cephalopods of the genus Heteroteuthis are the most pelagic members in the family Sepiolidae. This study examines the reproductive biology of Heteroteuthis dispar (Rüppell, 1844), the first such study on any member of the genus, based on 46 specimens (27 females and 19 males) collected during the Mar-Eco cruise in the North Atlantic in the region of the Mid-Atlantic Ridge in 2004, and compares it with reproductive features in the less pelagic members of the family. The unusually large spermatophores of the males have a very small ejaculatory apparatus and cement body, relative to the size of the sperm mass. Females first mate when they are still maturing: a large sperm mass (up to 3.4% of the female body mass), consisting of one to several spermatangia, was found in an internal seminal receptacle of the majority of the females examined regardless of their maturity state. The seminal receptacle has a unique form and position in this species. The receptacle is a thin-walled sac at the posterior end of the visceral mass that is an outpocketing of, and opens into, the visceropericardial coelom. Spermatangia and sperm from the spermatangia apparently enter into the visceropericardial coelom (which is mostly occupied by the ovary) from the seminal receptacle indicating that ova are fertilised internally, a strategy unknown for decapodiform cephalopods (squid and cuttlefish), but present in most octopods. Fecundity of Heteroteuthis dispar (1,100–1,300 oocytes) is much higher than in other sepiolids whereas the egg size (mean max. length ∼1.6 mm) is the smallest within the family. Spawning is continuous (sensu Rocha et al. in Biol Rev 76:291–304, 2001). These and other reproductive traits are discussed as being adaptations to an oceanic lifestyle

Reproductive biology of the common cuttlefish Sepia officinalis L. (Sepiida: Cephalopoda) in the Aegean Sea

The common cuttlefish (Sepia officinalis) is known as one of the economically important species in the classis Cephalopoda. In this study, from October 2000 to April 2002, 674 cuttlefish were collected monthly from the surroundings of Homa lagoon (in the Aegean Sea). In order to determine reproductive behaviors and spawning season of S. officinalis species, the gonad stages of both sexes and the seasonal gonadosomatic index values were determined. It was observed that the spawning period of S. officinalis covers the whole year with two maximum peaks in March and June. © TÜBİTAK

Analysis of fecundity of some bobtail squid of the genus Sepiola (Cephalopoda: Sepiolida) in the Aegean Sea (eastern Mediterranean)

A total of 39 Sepiola intermedia, Sepiola robusta and Sepiola steenstrupiana samples (11 female, 28 male), from the eastern Mediterranean and the Aegean Sea have been examined. The potential fecundity, relative fecundity and index of potential reproductive investment were calculated

Reproductive biology of the bobtail squid Rossia macrosoma (Cephalopoda: Sepiolidea) from the Eastern Mediterranean [Dogu Akdeniz'de Rossia macrosoma'ni{dotless}n (Cephalopoda: Sepiolidea) Üreme Biyolojisi]

Rossia macrosoma was investigated based on material collected from the eastern Mediterranean Sea, to determine potential fecundity (PF), reproductive strategies and size at maturity. The female potential fecundity ranged between 126 and 931, while the value was 15 to 103 for male spermatophores. Egg sizes varied from 0.2 to 10.0 mm, and spermatophore lengths ranged from 12.3 to 18.8 mm. Animals became mature at smaller sizes than those from the western Mediterranean, thus, their maximum sizes were smaller either. According to egg diameter distributions in gonads, R. macrosoma has asynchronous ovary maturation, spawning more than once. Therefore, R. macrosoma is an intermittent spawner similar to other sepiolid species. © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey

Reproductive biology of the Patagonian bobtail squid, Semirossia patagonica (Sepiolidae: Rossiinae) in the south-west Atlantic

A total of 104 Semirossia patagonica were collected all over the Patagonian shelf between the depths of 47 and 295 m. Mature female size varied from 10 to 35 mm ML, mature male size was 16-32 mm. Potential fecundity ranged between 527-766 eggs in pre-spawning females, ripe egg size was 3.4-5.0 mm. The oviduct capacity probably was no more than 30 eggs. The maximum number of spermatophores in males was 229. Males transfer 2-19 spermatophores to females during copulation. The ovulation pattern is asynchronous, individual spawning is continuous. Reproduction occurs all year round. Semirossia patagonica is a south-west Atlantic ecological sibling of north-east Atlantic bobtail squids Sepiola spp. and Sepietta spp. Copyright © Marine Biological Association of the United Kingdom 2008