Pseudocandona cillisi, Higuti & Martens, 2014

Higuti, Janet & Martens, Koen, 2014, Five new species of Candoninae (Crustacea, Ostracoda) from the alluvial valley of the Upper Paraná River (Brazil, South America), European Journal of Taxonomy 106, pp. 1-36 : 16-20

Pseudocandona cillisi sp. nov.

urn:lsid:zoobank.org:act:DC713AC3-23AA-4056-AE25-020DD6A1257C

Figs 6–7

“ Candona ” sp. 1 n. sp. Higuti et al., 2009c: 664. “ Candona ” sp. 1 n. sp. Higuti et al., 2010: 267.

Diagnosis

Valves small, high and short in lateral view. Anterior calcified inner lamella in both valves relatively broad; posterior calcified inner lamella very narrow. Second segment of Md palp with 4 setae. Prehensile palps distally hook-like, relatively short and set with one sub-apical spine and one sub-apical setae. Penultimate segment of T3 not divided; seta h1 ca. 1/3 of the length of seta h2. Hemipenis with lobe a short and broad, distal margin only slightly rounded, lobes b and h almost completely overlapping, asymmetrically rounded and pointed towards the ventral side.

Etymology

The new species is named in honour of Julien Cillis (RBINS), in recognition of his continuous technical assistance with the scanning electron microscopy (SEM) images of ostracod valves at RBINS for more than 2 decades.

Type material

All type material was collected on 7 Nov. 2004 by the authors, by washing roots of floating plants ( PAR 150) in a bucket and the material was filtered in a hand net with mesh size 160 µm. See Table 1 for measurements of water chemistry at time of collecting.

Holotype

♂ carapace stored dry in a micropalaeontological slide ( MZUSP 32671 ).

Allotype

♀, with soft parts dissected in glycerine in a sealed slide, and with valves stored dry in a micropalaeontological slide ( MZUSP 32672 ).

Paratypes

A ♂ dissected,with LV stored dry in a micropalaeontological slide (OC. 3363); four ♂♂ dissected and with the valves lost ( MZUSP 32673, MZUSP 32674, MZUSP 32675, MZUSP 32676); two ♂ carapaces stored dry in micropalaeontological slides ( MZUSP 32677, OC. 3362); four ♀ carapaces stored dry in micropalaeontological slides ( MZUSP 32678, MZUSP 32679, MZUSP 32680, OC. 3364).

Other material investigated

A ♂ dissected, with soft parts lost and with valves stored dry in a micropalaeontological slide ( MZUSP 32681) from Baía River ( PAR 195) is also deposited in the Museu de Zoologia da Universidade de São Paulo, São Paulo.

Type locality

BRAZIL: Aurélio Lake in Upper Paraná River floodplain in a mix of floating macrophyte species. Coordinates: 22º41’36.5” S, 53º13’52” W.

Differential diagnosis

Pseudocandona cillisi sp. nov. has valves which are much shorter and higher than those of P. geratsi and P. antilliana , while the (straight) dorsal margin is much more sloping than in P. caribbeana and P. cubensis . The new species also differs from P. annae Mehes, 1914 in the shape of the valves, which are more elongated in the latter species.

Description of male

Valves ( Fig. 6A–B ) small, high and short in lateral view, with greatest height situated behind the middle (and bluntly pointed there), anteriorly and posteriorly rather broadly rounded, RV and LV of highly similar shape; anterior calcified inner lamella broadly rounded, posterior calcified inner lamella narrow and narrower towards the dorsal side.

Carapace in right lateral view ( Fig. 6C ) showing LV overlapping RV slightly on all sides; anteriorly and posteriorly widely beyond the RV, external surface of valves smooth.

In dorsal view ( Fig. 6D ), carapace lancet-shaped, sharply pointed in the anteriorly, more broadly so posteriorly, greatest width situated well behind the middle.

Carapace also in ventral view ( Fig. 6E ) lancet-shaped, with anterior side more acutely pointed than posterior side, in V view with slight rostrum.

Md-palp ( Fig. 7C ) consisting of 4 segments. Basal segment dorsally carrying the respiratory plate (not shown), ventro-apically with 2 long setae (only one hirsute = s1), the alpha seta and a short, stout and hirsute seta s2. Second segment dorso-apically with 2 setae of unequal length, ventro-basally with a short, stout and hirsute seta and ventro-apically with a group of 5 setae: 2 long setae, 2 shorter (one hirsute), and the short beta-seta. Third segment with a group of 3 smooth dorso-subapical setae of unequal length, a central group of two setae, one of which being the gamma seta, and a ventro-apical group of 2 smooth setae. Terminal segment subquadrate, chaetotaxy as in P. agostinhoi sp. nov.

T1: Prehensile palps ( Fig. 7F, H ) distally hook-like and set with two unequal sub-apical setae; palps slightly asymmetrical, robust left prehensile palp ( Fig. 7F ) margin tightly rounded.

T2 (walking limb - Fig. 7B ) with 4-segmented endopodite (penultimate segment divided) and elongated. First segment with short seta d1. Knee-segment devoid of seta d2. First segment of endopod elongated, with short ventro-apical seta. Second segment also with one short ventro-apical seta. Third segment with two ventro-apical setae, one short, one slightly longer. Terminal segment with one short apical and one short sub-apical seta and a long apical claw.

T3 (cleaning limb, Fig. 7A ) as typical of the family. First segment with three setae, one short medial (d1), one short subapical (d2) and one long apical (dp). Second segment without seta. Penultimate segment with one long subapical seta (g). Terminal segment carrying three setae: 2 long (h2 and h3) and one very short (h1).

Caudal ramus (furca, Fig. 7D ) with stout ramus and two stout apical claws. Long proximal setae, distal seta a small spine. Attachment to caudal ramus ( Fig. 7E ) long and stout, distally bifurcated and with 2 additional lateral branches. Length ratio ramus / largest claw = 2.0.

Hemipenis ( Fig. 7G ) relatively small, with lobe a short and broad, distal margin only slightly rounded, lobes b and h almost completely overlapping, asymmetrically rounded and pointed towards the ventral side. Labyrinth with first (ascending) branch long, thin and slender; post-labyrinthal spermiduct S-shaped and simple.

Description of female

Valves ( Fig. 6F–G ): Cp in lateral view ( Fig. 6H ) and in D and V views ( Fig. 6I–J ) similar to those in the male.

Measurements

See Table 3 .

Figures

Fig. 6. Valves of Pseudocandona cillisi sp. nov. A–E ♂ and F–J ♀. A, F. LV, internal view (A = MZUSP 32681, F = MZUSP 32672). B, G. RV, internal view (B = MZUSP 32681, G = MZUSP 32672). C, H. Cp, right lateral view (C = MZUSP 32671, H = MZUSP 32678). D, I. Cp, dorsal view (D = OC. 3362, I = OC.3364). E, J. Cp, ventral view (E = MZUSP 32677, J = MZUSP 32680). Scale bars: A–B = 200 µm; C–E, H–J = 500 µm; F–G = 300 µm

Fig. 7. Limbs of Pseudocandona cillisi sp. nov. (♂). A. T3 (MZUSP 32673). B. T2 (MZUSP 32673). C. Md palp (MZUSP 32673). D. Caudal ramus (MZUSP 32673). E. Attachment of the caudal ramus (MZUSP 32673). F. Left prehensile palp (MZUSP 32673). G. Hemipenis (MZUSP 32673). H. Right prehensile palp (MZUSP 32673). Scale bars: A–H = 50 µm.