As killifish breeders, we often are faced with the question of “where are the eggs?” either when picking eggs from mops, or when checking peat in which fish have recently spawned. Sometimes there is no doubt that eggs are present: with some species, they are large, clear, and obvious. With other fish, the eggs may be extremely small, discolored from their proximity to peat, and deceptively difficult to see.
So how big are the eggs of various killifish? Recently Lee Harper shared the following information with the members of the killifish e-mail list (16 May 1998). Although the following list is far from complete, it may provide some guidance to other killikeepers.
Egg Size
Species / mm / in. / mils / micr.
E. annulatus / 0.90 / 0.035 / 35.43 /900
N. foerschi/ 0.95 / 0.037 / 37.40 / 950
A. striatum / 1.20 / 0.047 / 47.24 / 1200
A. cognatum Bandundu / 1.25 / 0.049 / 49.21 / 1250
A. rectogoense / 1.25 / 0.049 / 49.21 / 1250
A. bittaeniatum Ijebu Ode / 1.25 / 0.049 / 49.21 / 1250
A. australe #14 / 1.25 / 0.049 / 49.21 / 1250
N. voselleri Karogwe / 1.30 / 0.051 / 51.18 / 1300
A. cyanostictum (Diapteron) GBN 88/29 SAM / 1.30 / 0.051/ 51.18 / 1300
A. wachtersi Obili / 1.30 / 0.051 / 51.18 / 1300
A. fulgens (Diapteron) LEC 93/2 / 1.30 / 0.051 / 51.18 / 1300
E. chaperi Angona / 1.30 / 0.051 / 51.18 / 1300
F. gardneri nigerianum / 1.35 / 0.053 / 53.15 / 1350
P. omalonatus Nosy B‚ LM 94 / 1.45 / 0.057 / 57.09 / 1450
E. fasciolatus (embryo) / 1.50 / 0.059 / 59.06 / 1500
F. gardneri N’sukka / 1.60 / 0.063 / 62.99 / 1600
A. louessense RPC 33 / 1.60 / 0.063 / 62.99 / 1600
E. fasciolatus fasciolatus (new) / 1.60 / 0.063 / 62.99 / 1600
P. sakaramyi Joffreville LM/94 / 1.70 / 0.067 / 66.93 / 1700
A. sjoestedti / 1.80 / 0.071 / 70.87 / 1800
R. aff. holmiae / 2.10 / 0.083 / 82.68 / 2100
Ap. lineatus Gold / 2.10 / 0.083 / 82.68 / 2100
R. cryptocallus / 2.25 / 0.089 / 88.58 / 2250
Fundulus chrysotus / 2.40 / 0.094 / 94.49 / 2400
— G.C.K.A. Newsletter, Sept/Oct 1998