Fossil butterflies, calibration points and the molecular clock (Lepidoptera: Papilionoidea)
Author
Jong, Rienk De
text
Zootaxa
2017
4270
1
1
63
journal article
32975
10.5281/zenodo.583183
6c479acc-8b18-4f0b-a6e5-85bcd6d7b6b7
1175-5326
583183
2D00AFF5-4FE2-4EC1-A328-C8670CFB8D6D
florissanti
.
Barbarothea florissanti
Scudder, 1892
Nymphalidae
:
Libytheinae
.
USA
,
Colorado
, Florissant; late Priabonian, late Eocene.
Depository: Scudders' specimen is presumed lost (
Shields 1985
).
Published figures:
Emmel
et al
. (1992
:
Fig. 1
/2).
Very similar to the fossil
Prolibythea vagabunda
and also placed in the subfamily
Libytheinae (Nymphalidae)
by
Scudder (1892)
, followed by
Emmel
et al
. (1992)
. Fairly well preserved. Antenna tricarinate (autapomorphy of
Nymphalidae
), club very gradual. Two legs visible, not reduced, possibly middle legs. Palpi, 2nd segment oblique; apical joint horizontal, only a little more than two-thirds the length of the 2nd (i.e., relatively longer than in most butterflies, but shorter than in any known member of the
Libytheinae
). Venation as in
Prolibythea vagabunda
Scudder
that is plesiomorphic and not indicating relatedness. Hindwing relatively broad and rounded, costa concave, termen crenulate. Forewing slightly falcate. The long palpi agree with the
Libytheinae
, but apparently they had not yet reached the state found in extant members of the subfamily. Although the palpi of
Libytheinae
are relatively long, they are not unique, some other nymphalids having similarly long palpi and a similar venation as well (e.g.
Eunica
, a member of the
Biblidinae
). The apomorphic character states of the
Libytheinae
mentioned by
Ackery
et al
. (1999)
are not visible in the fossil, but the extension of the termen of the forewing at the end of M2 seems to occur in
Libytheinae
only as judged from the numerous venational diagrams in
Schatz & Röber (1892)
. In other butterflies, if there is an extension (a tooth) it is at or just below M1. It is not clear why Scudder did not place it in
Prolibythea
, although he mentioned the similarity. See also the discussion by
Kawahara (2013)
, who synonymized it with
Oligodonta florissantensis
and placed it in the extant genus
Libytheana
on the basis of an analysis of morphological characters. However, since apomorphies are not clear and the palpi are definitely shorter than in extant members of
Libythea
and
Libytheana
, I hesitate placing it in an extant genus and suggest that it should be placed at the stem node of the subfamily, if used for calibration purposes. See also under
Prolibythea vagabunda
.