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D.K. Elliott, E. Mark-Kurik, E.B. Daeschler. A revision of Obruchevia
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Halstead Tarlo (1964, p. 20; 1965, p. 149) explained in detail the problems concerning
the generic name. He published the family name, Obrucheviidae Tarlo, 1964, generic
name Obruchevia Whitley, 1940, and species name Obruchevia heckeri (Obruchev,
1936) as the valid ones (Halstead Tarlo 1965); however, he did not refer to Obruchev’s
paper of 1940. Obruchev and Mark-Kurik (1965, p. 19, 78) used the name Aspidosteus,
and mentioned Obruchev’s paper of 1940. They did not, however, describe the genus
Aspidosteus as the monograph concerned only the representatives of the family
Psammosteidae Traquair.
Obruchev could not and did not consider the name Obruchevia Whitley, 1940 as a
nomen nudum as Whitley correctly followed the Article 13 of the International Code of
Zoological Nomenclature (1964), referring to Obruchev’s paper of 1936. Obruchev (1964)
did not ignore Whitley’s (1940) corrections of fish names in other cases, either. For
example, he recognized Whitley as the author of the generic name Cyrtaspidichthys for
the genus Cyrtaspis Bryant, 1932. Whitley anticipated White and Moy-Thomas (1940),
who published a new name, Eucryptaspis, for Bryant’s genus only one month later (in
June 1940).
In many papers published after 1941 on Devonian biostratigraphy (e.g., Blieck et
al. 1988) and fish paleontology of the NW of the East European platform, including
Obruchev’s own papers (e.g., that of 1967), the name Aspidosteus (not Obruchevia)
was commonly used. It was, however, not the case with Halstead Tarlo who regularly
used the name Obruchevia in his publications (Halstead Tarlo 1963, p. 3; 1967b, p.
1233; Halstead 1969, p. 22; 1974, p. 61 etc.) but not yet in Halstead Tarlo 1962 (p. 261).
Therefore, in relation to the priority problem, the stability or universality criteria
cannot be applied (see Article 23 in the International Code of Zoological Nomenclature,
1999).
There seem to be two possibilities: (1), Obruchev considered his description of
Aspidophorus (later called Aspidosteus or Obruchevia) in 1936 not valid as publication
was in a popular science journal (Priroda); or (2), he published the name Aspidosteus in
some paper before May of 1940, i.e. before the correction was made by Whitley (however
we have not found such a paper). Halstead Tarlo (1964, p.124; 1965, p. 159) referenced
two of Obruchev´s papers in press (Obruchev, D., 1965a, “On the branchial
plates of Aspidosteus,” and Obruchev, D., 1965b, “Pycnosteus nathorsti n. sp. from the
Middle Devonian of Spitsbergen”) but unfortunately, neither was ever published.
It is concluded here that as Obruchev (1964, p. 75 in the Russian edition) clearly
indicated that the genus Aspidosteus was established by him in 1941, the priority belongs
to the name Obruchevia Whitley, 1940, and the name Aspidosteus Obruchev,
1941 is its junior synonym.
Localities. Obruchev (1964) mentioned that Aspidosteus was known from the Novgorod
Region, Russia, and from Latvia. According to Lukševičs (2001) Aspidosteus occurs in
Latvia in the Pamūšis Regional Stage, whereas in Lyarskaya and Lukševičs (1992) it was
mentioned as occurring in two units: the Katleši and Ogre (= Pamūšis) formations.
Lukševičs (pers. comm. 2003) is of the opinion that the occurrences of Aspidosteus from
Latvia were after all erroneously reported.
The main distribution area of Obruchevia is the Novgorod Region, NW Russia
(Fig. 2, upper left). Six Obruchevia (Aspidosteus) localities have been reported on the
River Lovat´ about 30 km upstream from the railway bridge of the connection between