Late Neogene Lophophaenidae (Nassellaria, Radiolaria) from the eastern equatorial Pacific
Author
Trubovitz, Sarah
Author
Renaudie, Johan
Author
Lazarus, David
Author
Noble, Paula
text
Zootaxa
2022
2022-07-04
5160
1
1
158
http://dx.doi.org/10.11646/zootaxa.5160.1.1
journal article
10.11646/zootaxa.5160.1.1
11755334
10544058
A9179C79-EE43-44E4-8723-919505500049
Lophophaena macrencephala
Clark and Campbell, 1945
partim.
Plate 21,
Figs. 7A
–
8B
.
Lophophaena macrencephala
n. sp.
,
Clark and Campbell, 1945
, pl. 7, figs. 6 and 9 (non figs. 7 and 8).
non
Lophophaena
sp. B
,
Petrushevskaya, 1971
, pl. 56, figs. 1–3.
non
Lophophaena macrencephala
Clark and Campbell,
Dzinoridze
et al.,
1978
, pl. 29, fig. 20; pl. 32, fig. 36.
non
Lophophaena macrencephala
Clark and Campbell,
Petrushevskaya and Kozlova, 1979
, figs. 348–349.
Lophophaena macrencephala?
,
Renaudie, 2014
, pl. 23, fig. 5.
Lophophaena macrencephala
? Clark and Campbell,
Trubovitz
et al.,
2020
, supplementary data 7.
Remarks.
There is a good deal of confusion regarding this species, and poor documentation in the literature.
Clark and Campbell (1945)
listed this species under the generic name
Lophophaena
, and the subgeneric name
Lophophaenula
. Because
Campbell (1954)
later synonymized the subgenus
Lophophaenula
under the genus
Lophophaena
, we drop the subgenus designation from the name.
Clark and Campbell (1945)
illustrated
four specimens
to accompany their species description. It is our opinion that at least two different species are included in these illustrations (pl. 7, figs.
6–9 in
Clark and Campbell, 1945
). Specimens 6 and 9 have a globular cephalis, slightly wider than the shoulder area of the thorax. However, specimens 7 and 8 have a relatively small, thumb-shaped cephalis, that is slightly narrower than the shoulders of the thorax. Specimen 7 also exhibits some cephalic pores more than twice the diameter of any pores on the other specimens. All specimens display a variable number of cephalic horns, and are broken in a way that does not show the full thorax. In their species description,
Clark and Campbell (1945)
note: “The 4 shells which we illustrate and assign to the present species may not all belong together. They have in common the swollen cephalis subequal in size, and very nearly in shape, but the horns are different. One of them (fig. 9) has no horns at all, while the others have one (fig. 8) or more (figs. 6–7). The last are considered to be typical of the species.” Although we disagree with
Clark and Campbell (1945)
that all the shells exhibit a “swollen” cephalis and are similar in shape or size, we do agree that these
four specimens
do not belong to the same species. Specifically, the specimens considered “typical” by Clark and Campbell (figs. 6 and 7) are in our opinion almost certainly different species. Furthermore, the presence of multiple spines on the cephalis alone is not a sufficient reason to group the specimens in fig. 6 and fig. 7.
Petrushevskaya and Kozlova (1979)
’s concept of
L. macrencephala
includes
Clark and Campbell (1945)
’s figs. 7–8, but excludes figs. 6 and 9.
Petrushevskaya and Kozlova (1979)
consider this species to be similar to
L. apiculata
(=
L. galeaorci
), but is overall smaller in size. The specimens questionably assigned to
Lophophaena macrencephala
in
Trubovitz
et al.
(2020)
are most similar to
Clark and Campbell (1945)
’s illustrated specimens in figs. 6 and 9, in terms of segment proportions and pore size. Clark and Campbell’s fig. 6 and fig. 9 appear to most closely match their own description of the species, as these could be described as having a “globular” or “swollen” cephalis. The specimens in figs 7–8 appear to belong to two different species due to the different pores sizes on the cephalis and the size of the cephalis itself, and so we do not follow
Petrushevskaya and Kozlova (1979)
’s revision of the species concept. As they also listed
Petrushevskaya (1971)
’s
Lophophaena
sp. B
in their synonymy, we examined this specimen and concluded that it does not fit our concept of
L. macrencephala
. Instead, we adopt Clark and Campbell’s fig. 6 and fig. 9 as the concept for
Lophophaena macrencephala
.
In addition to some of the
type
specimens, our illustrations here and in
Trubovitz
et al.
(2020)
,
Renaudie (2014)
also illustrated a similar specimen as
Lophophaena macrencephala
?
(pl. 23, fig.
5 in
Renaudie, 2014
) that could be conspecific with ours, and our accepted part of Campbell and
Clark (1945)
’s concept. To fully resolve this concept however, the original
type
material will need to be examined, which is beyond the scope of this project.
Range.
Late Miocene, EEP (
Table 1
).