153 
National Marine 
Fisheries Service 
NOAA 
Fishery Bulletin 
& established in 1881 
Spencer F. Baird 
First U S Commissioner 
of Fisheries and founder 
of Fishery Bulletin 
Gonadal maturation of the female smooth 
lumpsucker [Aptocyclus ventricosus) 
1 Russian Federal Research Institute of Fisheries and Oceanography (VNIRO) 
1 7 V. Krasnoselskaya Street 
Moscow, 107140, Russian Federation 
2 A N. Severtsov Institute of Ecology and Evolution 
Russian Academy of Sciences 
33 Leninskij Prospect 
Moscow, 119071, Russian Federation 
3 Dagestan State University 
43-a Gadzhiyev Street 
Makhachkala, 367000, Russian Federation 
Abstract —Features of oogenesis, 
ovarian maturity phases, and fecun¬ 
dity of the smooth lumpsucker f Ap¬ 
tocyclus ventricosus) are described 
here for the first time. Gonadal de¬ 
velopment was examined by histo¬ 
logical methods and the morphologi¬ 
cal features and size of germ cells 
at various stages was determined. 
These features were used to more 
accurately define morphological cri¬ 
teria of 7 histological and macro¬ 
scopic maturity phases. The smooth 
lumpsucker is an iteroparous gono- 
choristic species with determinate 
fecundity, group-synchronous ovary 
organization, total spawning (release 
of 1 batch of eggs per breeding sea¬ 
son), and external fertilization. 
Manuscript submitted 12 April 2017. 
Manuscript accepted 19 January 2018. 
Fish. Bull. 116:153-160 (2018). 
Online publication date: 2 February 2018. 
doi: 10.7755/FB.116.2.4 
The views and opinions expressed or 
implied in this article are those of the 
author (or authors) and do not necessarily 
reflect the position of the National 
Marine Fisheries Service, NOAA. 
Kristina Zhukova (contact author) 1 
Olga A. Maznikova 1 
Alexei M. Orlov 1 - 2 ' 3 ' 4 
Email address for contact author: kzh@vniro.ru 
4 Tomsk State University 
36 Lenina Street 
Tomsk, 634050, Russian Federation 
The family Cyclopteridae is repre¬ 
sented by about 16 genera and 28 
species (Eschmeyer et al., 2017) that 
inhabit the cold waters of the north¬ 
ern hemisphere (Nelson et al., 2016). 
The lumpfish (Cyclopterus lumpus) is 
a commercial fish and the most stud¬ 
ied member of this family (Goulet et 
al., 1986; Goulet and Green, 1988). 
Other members of this family have 
been studied less frequently, and in¬ 
formation about their reproductive 
biology is fragmentary and scarce. 
The smooth lumpsucker (Aptocy¬ 
clus ventricosus ) is a widely distrib¬ 
uted marine fish species that is en¬ 
demic to the North Pacific. It inhab¬ 
its both near bottom and mid-water 
layers at depths ranging from 5 to 
1700 m (Hart, 1973; Eschmeyer et 
al., 1983; Orlov and Tokranov, 2008). 
It is a common species that is eco¬ 
logically relevant to local food webs 
throughout its distribution. It is a 
major consumer of gelatinous plank¬ 
tonic animals, such as jellyfishes and 
comb jellies (Yoshida and Yamagu- 
chi, 1985) and an important source 
of food for some fish species, marine 
mammals, and birds (Kato, 1982; Or¬ 
lov, 1997; Zeppelin and Ream, 2006; 
Anthony et al., 2008; Sinclair et al., 
2008). 
There is little information avail¬ 
able on the spawning features (e.g., 
behavior, physical changes) or em¬ 
bryonic, and larval development of 
the smooth lumpsucker. It is only 
known that this species performs 
spawning migrations from deep wa¬ 
ter to coastal zones, where breed¬ 
ing occurs over a rocky bottom at 
depths shallower than 10 m. Eggs 
are demersal and adhesive and have 
an average diameter of 2.4 mm. The 
incubation time between fertilization 
and hatching is more than 40 d. Re¬ 
portedly, females die after spawning 
and males continue to protect the 
egg clusters (Kyushin, 1975; Ilynsky 
and Radchenko, 1992; Mecklenburg 
et al., 2002; Fadeev, 2005). Spawn- 
