It is just good horticultural practice to name the mother plant first. As they are cultivars, plants of the same parents my NOT be given the cultivarname unless the standard says it may be done (non vegetative reproduction allowed).
This is what the ICPS database says:
N: $[Pinguicula ' Sethos ' {Hort.Slack}]
P: Insect-Eat.Pl. & How to Grow Them:113 (1986)
S: =[[Pinguicula ehlersiae {Speta & Fuchs}] * [Pinguicula moranensis {H.B.K.}]]
B: H.Weiner, Hameln, 1981
Nominant: H.Weiner
Registrant: A.Slack
HC: Registered 10. 11. 1998 {JS}
Description: Insect-Eat.Pl. & How to Grow Them:113 (1986)
"Of these (hybrids) I would mention [Pinguicula ' Sethos ' {Hort.Slack}] ([[Pinguicula moranensis {H.B.K.}] * [Pinguicula ehlersiae {Speta & Fuchs}]]), a fine, very floriferous clone with large orchid-purple flowers with a many-rayed mouth like a white star;
[Pinguicula ' Weser ' {Hort.Slack}], of the same parentage and with rather similar flowers, has a solitary white streak down the central lower lobe and dark veins." Standard: {Oliver Gluch}
Etymology: obscure (perhaps alluding to a Pharaoh)
image: Check Bob Ziemer's Photo Finder
N: $[Pinguicula ' Weser ' {Hort.Slack}]
P: Insect-Eat.Pl. & How to Grow Them:113 (1986)
S: =[[Pinguicula moranensis {H.B.K.}] * [Pinguicula ehlersiae {Speta & Fuchs}]]
B: H.Weiner, Hameln, 1981
Nominant: H.Weiner
Registrant: A.Slack
HC: Registered 10. 11. 1998 {JS}
Description: Insect-Eat.Pl. & How to Grow Them:113 (1986)
"Of these (hybrids) I would mention [Pinguicula ' Sethos ' {Hort.Slack}] ([[Pinguicula moranensis {H.B.K.}] * [Pinguicula ehlersiae {Speta & Fuchs}]]), a fine, very floriferous clone with large orchid-purple flowers with a many-rayed mouth like a white star; [Pinguicula ' Weser ' {Hort.Slack}], of the same parentage and with rather simiar flowers, has a solitary white streak down the central lower lobe and dark veins."
Standard: Insect-Eat.Pl. & How to Grow Them:114 (1986)
Etymology: after the river at originator's locality
image: pinguicu/pxweser: flowering plant
image: Check Bob Ziemer's Photo Finder
The difference seem to be the white streak, as such both plants are more Weser than Sethos but the don't look like Slack's original photo (check the photo finder
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