So I am a little clearer what Salvadori & Antinori 1872 meant and what the Italian museum meant. Salvidori says Heuglin called horus a variety of C. affinis. A subspecies? Salvidori say no C. horus is a full species. Therefore Antinori’s Sudan bird is the type of C. horus. With authors Salvidori and Antinori? I’m not sure it works that way.
The name is to be attributed to
Heuglin 1869, who first associated it to a description. (Heuglin could admittedly be read as not having treated this name as valid but, even in this case, the name would still date from his work as a result of having been subsequently adopted by
Salvadori & Antinori 1872.)
The type(s) should be the specimen(s) that formed the base of Heuglin's description.
This will include any specimen that would have been labelled as "
Cypselus Horus" by Hartlaub & Finsch prior to 1869. This might, or not, include Antinori's Blue Nile specimen (the Torino bird) -- but more likely not. As noted by Mark above, Heuglin cited
Antinori's 1864 Catalogo, where this specimen is listed in his synonymy; but he did not associate it directly to the
Varierät; in the
Catalogo, this specimen is called
Cypselus galilejensis, and comes with a Latin diagnosis that is nearly identical to the diagnosis given by Antinori in the
OD of this taxon, and nothing that would suggest it matched Heuglin's description of the
Varietät better : this specimen could be a type only if Heuglin knew how the specimen looked like from some other source (and forgot to make this apparent). In the text, Heuglin cited specimens (
einige -- more than one) from South Africa, labelled
Cypselus caffer in the
Stuttgarter Naturalienkabinet, which he said he also included in
dieser Art (i.e., in
Cypselus affinis), and which resembled the
C. horus variety; he gave a separate short description of these birds; in my reading, this shows that Heuglin did not include these birds positively in
horus, hence I don't think they can have been types of the taxon either. (I cannot tell whether there might have been other birds at Stuttgart than these.)
Beware that
Brooke 1971, when he described
Apus horus fuscobrunneus, attributed
horus directly to Salvadori & Antinori 1872, and apparently treated Antinori's bird as the type. This is not tenable if the name dates from Heuglin 1869.
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