Siamopsis renateae Savatenalinton 2017, gen. et sp. nov.
Creators: name: Savatenalinton, Sukonthip
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Ostracoda
Podocopida
Cytheruridae
Siamopsis
Siamopsis renateae

description: Siamopsis renateae gen. et sp. nov.
urn:lsid:zoobank.org:act: 1C17AC72-8E9E-4D70-B202-3A14626F2A74
Figs 1–4, 19A, 20
Diagnosis
Carapace in lateral view subtriangular, dorsal margin strongly arched, slightly angulated at posterodorsal part, greatest height situated in front of mid-length, RV overlapping LV anteriorly, ventrally, posteriorly. Valve surface set with long (rim-pore) setae and shallow pits dispersedly. Carapace in dorsal view tumid with even lateral margins. LV in internal view, with large marginal zone anteriorly, both anterior and posterior valve margins subequally rounded, postero-dorsal plate broad with two small marginal teeth-like tubercles, inner lamella calcified, with inner lists anteriorly and posteriorly. RV in internal view with large marginal zone anteriorly, inner lamella with inner lists anteriorly and posteriorly, without small tubercle-like structures under posterior inner list. Mx1 third endite with two (one smooth, one serrated) large bristles, terminal segment of Mx1 palp cylindrical, very elongated. CR of cylindrical shape, with flagellum-like seta.
Etymology
This species is named after Dr. Renate Matzke-Karasz (Munich University, Germany) in appreciation of her outstanding work on ostracods and also for a long friendship.
Material examined
Holotype
THAILAND: ♀, with soft parts dissected in glycerine on a sealed glass slide and valves stored dry in a micropalaeontological slide (MSU-ZOC.190).
Paratypes
THAILAND: 1 ♀, same data as for holotype (MSU-ZOC.191–192); 2 ♀♀ carapaces, stored dry in micropalaeontological slides (MSU-ZOC.193–194); ca 5 ♀♀ in 70% EtOH.
Other material
THAILAND: Nakhon Ratchasima Province: Sikhiu District, Sub Pradu Reservoir (locality 2 in Fig. 20), 14°57′57″ N, 102°05′03″ E, 6 Feb. 2006. Accompanying ostracod fauna: Potamocypris sp., Physocypria sp. 2, Physocypria sp. 3, Limnocythere stationis Vavra, 1891, Strandesia (juveniles). – Phayao Province: Mae Jai District, Mae Peum Reservoir (locality 3 in Fig. 20), 19°21′29″ N, 99°51′45″ E, 7 Oct. 2007. Accompanying ostracod fauna: Hemicypris exigua Broodbakker, 1983, Stenocypris malayica Victor & Fernando, 1981, Bradleystrandesia weberi (Moniez, 1892), Bradleytriebella lineata (Victor & Fernando, 1981), Pseudostrandesia mamarilorum (Victor & Fernando, 1981), Strandesia kraepelini (Müller, 1906), S. perakensis Victor & Fernando, 1981, Tanycypris siamensis Savatenalinton & Martens, 2009, Cypretta sp. and Physocypria sp. 3. – Chiang Rai Province: Chiang Saen District, rice field (locality 4 in Fig. 20), 20°16′10″ N, 100°03′09″ E, 25 Sep. 2005. Accompanying ostracod fauna: Vestalenula boteai (Danielopol, 1970) and Strandesia (juveniles). – Phitsanulok Province: Wat Boht District, roadside canal (locality 5 in Fig. 20), 16°09′52″ N, 100°19′47″ E, 12 Feb. 2006. Accompanying ostracod fauna: Chrissia humilis (Klie, 1932), Hemicypris exigua, Pseudostrandesia mamarilorum, Pseudocypretta maculata Klie, 1932, Physocypria sp. 1, Physocypria sp. 2, Ilyocypris sp. and Limnocythere stationis Vavra, 1891. – Phetchabun Province: Muang District, Nong Naree (swamp) (locality 6 in Fig. 20), 16°26′24″ N, 101°08′29″ E, 9 Oct. 2007. Accompanying ostracod fauna: Bradleycypris vittata (Sars, 1903), Bradleystrandesia weberi, Strandesia kraepelini, Cypretta sp. 3, Potamocypris sp., Siamopsis planitia gen. et sp. nov., Physocypria sp. 2 and Physocypria sp. 3. – Chaiyaphum Province: Konsarn District, rice field (locality 7 in Fig. 20), 16°23′3″ N, 101°58′47″ E, 9 Oct. 2007. Accompanying ostracod fauna: Pseudostrandesia calapanensis (Tressler, 1937), P. mamarilorum, Strandesia sexpunctata Klie, 1932, Cypretta sp. 3 and Physocypria sp. 1. – Chaiyaphum Province: pond (locality 8 in Fig. 20), 16°23′3″ N, 101°58′47″ E, 9 Oct. 2007. Accompanying ostracod fauna: Cypris subglobosa Sowerby, 1840, Strandesia sexpunctata, Cypretta sp. 3 and Physocypria sp. 1.
Type locality
THAILAND: Nakhon Ratchasima Province, Muang District, irrigation ditch (locality 1 in Fig. 20), 14°43′46″ N, 104°33′56″ E, 5 Oct. 2010. Accompanying ostracod fauna: Cypris subglobosa Sowerby, 1840, Cyprinotus uenoi Brehm, 1936, Stenocypris cf. orientalis Victor & Fernando, 1981, Siamopsis khoratensis gen. et sp. nov., S. conspecta gen. et sp. nov. and S. planitia gen. et sp. nov.
Differential diagnosis
Siamopsis renateae gen. et sp. nov. differs from the other species of the new genus by the presence of a strongly arched dorsal margin, resulting in the subtriangular carapace in lateral view (elongated shape in other species), the postero-dorsal plate on LV having two small, teeth-like tubercles on the inner border and the absence of tiny tubercle-like structures under the RV posterior inner list. Additionally, the ya and accompanying seta on A1 are subequal in length in S. renateae gen. et sp. nov. while the length of the accompanying seta is ca ⅔ that of ya in other species of Siamopsis gen. nov. Compared to the g-seta on T2, the length of the seta located next to the g-seta is short (ca ⅓ of g-seta) in S. renateae gen. et sp. nov. The length of this seta is ca half of that of the g-seta in other species of Siamopsis gen. nov.
Measurements (mean, in μm)
LV (n = 2), L = 653, H = 393; RV (n = 2), L = 649, H = 401; carapace (n = 2), L = 631, W = 302.
Description
Female
CARAPACE. In lateral view (Fig. 1A) subtriangular, anterior margin rounded, posterior margin narrower rounded, dorsal margin strongly arched and slightly angulated at postero-dorsal part, greatest height situated in front of mid-length, RV overlapping LV anteriorly, ventrally and posteriorly, valve surface set with long setae, long rim-pore setae and shallow pits dispersedly. Carapace in dorsal view (Fig. 1B, G) tumid, with evenly curved lateral margins, greatest width situated at mid-length, posterior extremity round, anterior extremity more pointed.
VALVES. LV in internal view (Fig. 1D, H) with large marginal zone anteriorly, both valve margins subequally rounded, ventral margin sinuous at mid-length, postero-dorsal plate broad, with two small marginal teeth-like tubercles, calcified inner lamella with inner lists anteriorly and posteriorly. RV in internal view (Fig. 1E, I) with large marginal zone anteriorly, ventral margin sinuous at mid-length, inner lamella calcified with inner lists anteriorly and posteriorly.
A1 (Fig. 2A). Seven-segmented, first segment with large proximal Wouters organ, one long dorsosubapical seta (reaching beyond tip of next segment) and two long ventro-apical setae. Second segment slightly wider than long, with one long dorso-apical seta (reaching tip of next segment) and Rome organ. Third segment bearing two setae: one long dorso-apical (reaching tip of penultimate segment) and one short ventro-apical. Fourth segment with two long dorsal setae and two short ventral setae (both reaching beyond half of fifth segment). Fifth segment dorsally with two long setae, ventrally with two (one long, one short) setae, short one reaching beyond end of next segment. Penultimate segment with four long apical setae. Terminal segment with three (two long, one short) apical setae and long aesthetasc ya, length of short seta ca ⅓ of aesthetasc ya.
A2 (Fig. 2B). Exopodite with three (one long, two short) setae, long one reaching beyond tip of first endopodal segment. First endopodal segment with five long (reaching far beyond tips of terminal claws) and one short natatory seta, length of shortest seta ca half that of penultimate segment, aesthetasc Y long, ventro-apical seta long, extending beyond tip of terminal segment. Penultimate segment undivided, distally with three serrated claws (G1, G2, G3), G2 shorter (length of G2 ca ¾ that of G1), aesthetasc y2 long (ca half of terminal segment), z1–z3 setae long; this segment medially with two subequally long dorsal setae, two ventral setae of unequal length (t1–t2). Terminal segment distally with two serrated claws (GM and Gm), length of Gm ca ⅔ that of GM; medially with short g-seta and ventral aesthetasc y3, length of aesthetasc y3 and accompanying seta subequal.
MD PALP (Fig. 3A). First segment with two large setae, one long and slender seta, and a short, smooth α-seta. Second segment dorsally with three unequal long apical setae; ventrally with group of three long hirsute setae, one shorter hirsute seta and plumose, cone-shaped β-seta with pointed tip. Penultimate segment with three groups of setae: dorsally with group of four unequal, long, subapical setae; laterally with apical γ-seta and three further apical setae (two smooth, one hirsute), the former thin and long (length ca 2.2 times that of terminal segment); ventrally with two subapical setae, one very long (reaching beyond tip of terminal segment), one short (ca half length of terminal segment). Terminal segment elongated, bearing three claws and two shorter setae.
MX 1 (Fig. 3B). With two-segmented palp, basal segment of palp dorsally with group of five long, unequal apical setae; ventrally with one short subapical seta. Terminal segment very elongated (length ca 2.8 times width), apically with three claws and two setae. Third endite with two (one smooth, one serrated) large bristles. Sideways-directed bristles on first endite unequally long, length of short one ca half that of long one.
T1 (Fig. 3 C–D). Protopodite with two unequally short a-setae, b- and d-setae absent, distally with ca 12 hirsute apical setae of unequal length. Endopodite with weakly built palp, with one very long, hirsute and two unequally short apical setae.
T2 (Fig. 4A). With d2 seta (d1 absent). Second segment with long e-seta (reaching tip of penultimate segment). Penultimate segment divided, proximal segment bearing long f-seta (reaching beyond tip of terminal segment), distal segment with pair of apical setae (g-seta, one short), g-seta very long (with almost the same length as h1 seta). Terminal segment with two (one dorsal, one ventral) apical h1 and h3 setae (length of former ca half that of claw, latter short) and serrated claw (h2), length of h2 longer than that of penultimate segment.
T3 (Fig. 4B). A cleaning limb. First segment with long d1, d2 and dp setae, d1 and d2 setae subequal in length. Second segment with long apical e-seta (reaching half of next segment). Third segment with medially long f-seta (reaching tip of segment). Terminal segment with an apical pincer and one reflexed subapical seta, length of latter equal to that of third segment.
CR (Fig. 4C). Reduced, flagellum-like, of cylindrical shape, with a small lateral seta and long apical seta, length of latter ca 1.7 times that of ramus.
Male
Unknown.
Ecology
The new species has thus far been recorded from eight localities in the Northern and Northeastern provinces: Nakhon Ratchasima, Chaiyaphum, Phayao, Chiang Rai, Phitsanulok and Phetchabun. It occurs at a pH range of 6.5 – 7.2, a temperature range of 26.1 – 29.5°C and a dissolved oxygen (DO) range of 3.20 – 7.80 mg /l.
description: Published as part of Savatenalinton, Sukonthip, 2017, Siamopsis gen. nov. and five new species of the subfamily Cypridopsinae Kaufmann, 1900 (Crustacea: Ostracoda) from Thailand, pp. 1-39 in European Journal of Taxonomy 384 on pages 4-11, DOI: 10.5852/ejt.2017.384, http://zenodo.org/record/3839820