On new terrestrial ostracods (Crustacea, Ostracoda) from Brazil, primarily from São Paulo State
Author
Pinto, R. L.
Author
Rocha, C. E. F.
Author
Martens, K.
text
Zoological Journal of the Linnean Society
2005
2005-10-31
145
2
145
173
https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2005.00185.x
journal article
10.1111/j.1096-3642.2005.00185.x
0024-4082
5434946
TRIBE
TERRESTRICYPRIDINI
(
SHORNIKOV, 1980
)
(CHANGE OF RANK)
Diagnosis
Small (L =
0.3–0.4 mm
) candonids, with reniform valves in lateral view and narrow carapace with straight margins in dorsal view. All limbs with some aspect of reduced chaetotaxy (fusion of segments, loss of setae) to varying degrees in the different genera. A1 with 5 segments, with various segments fused in the different genera; endopodal segments 1 and 2 +
3 in
T3 devoid of setae.
Remarks
1.
Shornikov (1980)
created the new family
Terrestricyprididae
to accommodate
Terrestricypris
. However, this genus clearly belongs in the
Candonidae
, a group where reduction in chaetotaxy (i.e. number of segments, number of setae and claws) is not uncommon (see
Danielopol, 1978
;
Karanovic & Marmonier, 2003
; I. Karanovic unpubl. data). This taxon is here retained, albeit with a change of rank, namely as a tribe within the
Candoninae
.
2.
Terrestricypridini
at present comprises 3 genera,
Terrestricandona
,
Terrestricypris
and
Caaporacandona
gen. nov.
, which together form a clear evolutionary lineage (see Discussion). It is possible that more genera will be found that will represent either more or less derived stages of evolution within this lineages. In the latter case, the diagnosis of the tribe might require modification.
3. Karanovic, in a series of papers (2003a, b and several papers in press), has described an impressive number of species and genera of subterranean
Candoninae
from
Western Australia
. These ostracods also display loss of chaetotaxy in, amongst other limbs, the A1. However, the Australian interstitial taxa mostly also have a reduction in the chaetotaxy of the CR, which is well developed in all
Terrestricypridini
, and have very different valves. It is thus accepted here that the South American terrestrial and Autralian interstitial candonids belong to different lineages.
4. Species of all three genera of
Terrestricypridini
have a distinct juvenile aspect (small size, narrow calcified inner lamella, reduced number of muscle scars). It is therefore probable that the presence of these genera in the fossil record has consistently been overlooked.