Thaicypridopsis longispinosa, Savatenalinton, 2018

Savatenalinton, Sukonthip, 2018, New genus of subfamily Cypridopsinae Kaufmann, 1933 (Crustacea: Ostracoda) from Thailand, European Journal of Taxonomy 487, pp. 1-17 : 4-11

Thaicypridopsis longispinosa gen. et sp. nov.

urn:lsid:zoobank.org:act:8C42600E-3232-40EF-BC77-765E1CC15953

Figs 1–4

Etymology

The specific epithet ‘longispinosa’ refers to the outstanding appearance of long spines on valve surface. This is the most prominent character of the new species and can be easily recognized from external morphology.

Type material

Holotype

THAILAND – Buriram Province (NE) • ♀ (soft parts dissected in glycerine on a sealed glass slide and valves stored dry on a micropalaeontological slide); Huai Jorakae Mak (reservoir), Muang district ; 14°54΄41˝ N, 103°03΄07˝ E; 4 Oct. 2010; MSU-ZOC.257.

Paratypes

THAILAND – Buriram Province (NE) • 3 ♀♀ (stored as the holotype); same locality as for holotype; 4 Oct. 2010; MSU-ZOC.258, 261 to 262 • 2 ♀♀ (stored as the holotype); Kwan Phayao (lake); 6 Oct. 2007; MSU-ZOC.263 to 264 • 2 ♀♀ (carapaces stored dry on micropalaeontological slides); same locality as for holotype; 4 Oct. 2007; MSU.ZOC.259 to 260 • 1 ♀ (carapace stored dry on micropalaeontological slide); Kwan Phayao (lake); 6 Oct. 2007; MSU.ZOC.265 • 9 ♀♀ (in 70% ethanol); same locality as for holotype; 4 Oct. 2010; MSU.ZOC.266 .

Type locality

A total of 15 female specimens (1 holotype, 14 paratypes) were collected at the type locality on 4 Oct. 2010 and 3 female specimens (in 70% ethanol) were collected at the type locality on 8 Feb. 2011. Accompanying ostracod fauna (4 Oct. 2010): Alicenula sp., Bradleystrandesia weberi (Moniez, 1892) , Bradleytriebella lineata (Victor & Fernando, 1981) , Cypretta sp.1, Cypretta sp.2, Cypridopsine sp., Dentocypria chantaranothaii Savatenalinton, 2017 , Metacypris srisumonae ( Savatenalinton et al., 2008) , Pseudocypretta maculata Klie, 1932 , Pseudostrandesia mamarilorum (Victor & Fernando, 1981) , Pseudostrandesia striatoreticulata (Klie, 1932) , Stenocypris sp., Strandesia hornei Savatenalinton & Martens, 2010 , Strandesia kraepelini (Müller, 1906) ; accompanying ostracod fauna (8 Feb. 2011): Cypretta sp.1, Cypretta sp.2, Cypridopsine sp., Bradleystrandesia weberi , Pseudocypretta maculata , Pseudostrandesia mamarilorum , Pseudostrandesia striatoreticulata, Stenocypris sp., Strandesia kraepelini .

Other material examined

THAILAND – Phayao Province ( N) • 7 ♀♀; locality 1; Kwan Phayao (lake), Muang District ; 19°09΄33˝ N, 99°54΄36˝ E; 6 Oct. 2007; accompanying ostracod fauna: Astenocypris papyracea (Sars, 1903) , Bradleystrandesia weberi , Bradleytriebella lineata , Cypretta sp., Cypridopsis vidua, Cypridopsine sp., Cypris subglobosa Sowerby, 1840 , Dentocypria smithi Savatenalinton, 2017 , Pseudostrandesia calapanensis (Tressler, 1937) , Pseudostrandesia mamarilorum, Stenocypris malayaica Victor & Fernando, 1981, Strandesia kraepelini , Tanycypris siamensis Savatenalinton & Martens, 2009 ; TH142 . – Roi-Et Province (NE) • 19 ♀♀; locality 2; Lam Phayom (reservoir); 16°17΄17˝ N, 103°59΄46˝ E; 25 Oct. and 20 Feb. 2010; accompanying ostracod fauna: Bradleystrandesia weberi , Bradleytriebella lineata, Cypridopsine sp., Dentocypria aequiloba , Dentocypria chantaranothaii , Limnocythere sp., Pseudocypretta maculata , Pseudostrandesia thailandensis Savatenalinton & Martens, 2010 , Stenocypris derupta Vávra, 1906, Strandesia kraepelini , Strandesia sexpunctata Klie, 1932 , Strandesia sp.; NE067. – Chaiyaphum Province (NE) • 5 ♀♀; locality 3; Nong PagPung (swamp), Phu Kiew District; 16°22΄27˝ N, 102°08΄02˝ E; 30 Oct. 2010; accompanying ostracod fauna: Candona sp., Cypridopsine sp., Dentocypria aequiloba , Pseudocypretta maculata, Stenocypris sp., Strandesia kraepelini , Strandesia sexpunctata ; NE073. – Chaiyaphum Province (NE) • 2 ♀♀; locality 4; Nong Sammuen (swamp), Phu Kiew District; 16°24΄27˝ N, 102°02΄02˝ E; 30 Oct. 2010; accompanying ostracod fauna: Metacypris srisumonae , Alicenula sp., Bradleystrandesia weberi , Cypretta sp., Dentocypria aequiloba , Dentocypria chantaranothaii , Pseudostrandesia mamarilorum , Strandesia kraepelini , Strandesia sexpunctata ; NE074. – Chaiyaphum Province (NE) • 2 ♀♀; locality 5; Lam Nam Kam (rivulet), Muang; 15°46΄37˝ N, 102°13΄18˝ E; 3 Oct. 2010; accompanying ostracod fauna: Bradleystrandesia weberi , Chrissia sp., Cypretta sp. 2, Cypridopsis vidua, Cypridopsine sp., Dentocypria aequiloba , Dentocypria chantaranothaii , Pseudocypretta maculata , Pseudostrandesia gaetani Savatenalinton & Martens, 2010 , Pseudostrandesia mamarilorum , Strandesia kraepelini , Strandesia sexpunctata ; NE007. – Chaiyaphum Province (NE) • 2 ♀♀; locality 6; Huai Pao (river), Kaset Sombun District, 16°23΄03˝ N, 101°58΄47˝ E; 9 Oct. 2007; accompanying ostracod fauna: Cypretta sp., Cypris subglobosa , Dentocypria chantaranothaii , Dentocypria smithi , Dolerocypris sisaketensis Savatenalinton & Suttajit, 2016 , Pseudostrandesia mamarilorum (Victor & Fernando, 1981) , Strandesia kraepelini (Müller, 1906) , Strandesia sexpunctata Klie, 1932 ; TH152. – Ubon Ratchathani Province (NE) • 2 ♀♀; locality 7; Kang Sapue (river), Phiboon Mangsahan District; 15°14΄37˝ N, 105°14΄37˝ E; 24 Oct. 2010; accompanying ostracod fauna: Chrissia sp., Cypridopsine sp., Pseudocypretta maculata , Pseudostrandesia calapaensis (Tressler, 1937) , Pseudostrandesia gaetani , Strandesia kraepelini , Strandesia sexpunctata ; NE057. – Buriram Province (NE) • 2 ♀♀; locality 8; Chon Pratan Reservoir, Lampaimas District; 15°01΄05˝ N, 102°50΄29˝ E; 8 Feb. 2011; accompanying ostracod fauna: Bradleystrandesia weberi , Dentocypria aequiloba , Pseudostrandesia thailandensis, Stenocypris derupta, Stenocypris sp., Strandesia kraepelini ; NE094. – Udon Thani Province (NE) • 2 ♀♀; locality 9; Nong Kae (swamp), Muang district; 17°27΄59˝ N, 102°48΄39˝ E; 31 Jan. 2011; accompanying ostracod fauna: Alicenula sp., Bradleystrandesia weberi , Chrissia sp., Cypretta sp., Cypridopsis vidua, Cypridopsine sp., Dentocypria aequiloba , Fabaeformiscandona sp., Metacypris srisumonae , Pseudocypretta maculata , Pseudostrandesia mamarilorum, Stenocypris derupta, Stenocypris sp., Strandesia hornei , Strandesia kraepelini ; NEN029. – Udon Thani Province (NE) • 2 ♀♀; locality 10; Huai Luang (reservoir), Muang district; 17°28΄20˝ N, 102°49΄12˝ E; 31 Jan. 2011; accompanying ostracod fauna: Alicenula sp., Chrissia sp., Cypretta sp. 1, Cypretta sp. 2, Dentocypria aequiloba , Pseudocypretta maculata , Strandesia kraepelini ; NEN030. – Mukdahan Province (NE) • 10 ♀♀; locality 11; Nong Lom (swamp), Don Tan District; 16°24΄18˝ N, 104°51΄30˝ E; 19 Dec. 2011; accompanying ostracod fauna: Cypridopsis vidua, Cypridopsine sp., Dentocypria aequiloba , Dolerocypris sp., Ilyocypris sp., Limnocythere sp., Pseudocypretta maculata , Strandesia kraepelini , Strandesia perakensis , Strandesia sexpunctata ; NEE003.

Diagnosis

Cp in lateral view subovate (length c. 1.5 times height) with maximum height situated at mid-length, anterior and posterior ends subequally rounded. CpD elliptical with maximum width situated slightly behind mid-length. LV overlapping RV all free margins. LV posterior part with double inner list, appearing well developed, but not oblique. RVi with a submarginal row of distinctive tubercles (c.18–20 tubercles) on postero-ventral part. Valve surface equipped with shallow pitted, dispersedly long setae and markedly long spines. Claw G2 on A2 strongly serrated with apical concavity, natatory setae long (far beyond end of terminal claw), four t-setae present in females with one seta claw-like appearance. Robust claw on Md-palp terminal segment with apical group of hairs. Terminal segment of Mx1-palp cylindrical and elongated, large bristles on three endites claw-like with hirsute endings and spatulashaped apexes, number of large bristles on first to third endite being 1, 1, 2, respectively. T1 with two a-setae (b-, c- and d-setae absent). Seta d2 on T2 present (d1 absent), terminal claw with slightly bifurcate ending. CR reduced, flagellum-like with triangular base.

Differential diagnosis

As Thaicypridopsis gen. nov. is a monospecific genus, the new species is compared with related species in other genera within the Cypridopsinae (also see Discussion below). The new species is superficially similar to Cabelodopsis hispida (Sars, 1901) Higuti & Martens, 2012 and Zonocypris costata (Vávra, 1897) due to the presence of a strongly serrated claw G2 on the A2 and of the tubercles on the posteroventral part of the RVi. The new species can be distinguished mainly by the robust apical claw on the terminal segment of the Md-palp with hairy ending (smooth and pointed endings in C. hispida and Z. costata ), the morphology of the large bristles on three Mx1-endites, which appear as hirsute endings and spatula-shaped apexes, and the presence of a bifurcated tip on the T2 terminal claw (smooth tip in C. hispida and Z. costata ).

Measurements (in μm)

Cp (n =2), L = 528–584, W = 334–378; LV (n= 3), L = 534–588, H = 349–408; RV (n =3), L = 507–578, H = 346–397.

Description

Female

CP IN LATERAL VIEW. Subtriangular, anterior margin rounded, posterior margin slightly wider rounded, dorsal margin strongly arched, greatest height situated at mid-length, LV overlapping RV all free margins, valve surface pitted and equipped with setae and long spines ( Fig. 1A–B ), surface of long spines slightly serrated ( Fig. 1D ).

CPD ( Fig. 1C ). Subovate with evenly curved lateral margins, greatest width situated slightly behind midlength, posterior extremity round, anterior extremity more pointed.

LVI ( Fig. 1F, H–I ). Both anterior and posterior margins subequally rounded, ventral margin sinuous at mid-length, submarginal selvage anteriorly, anterior calcified inner lamella wide with two inner lists, posterior calcified inner lamella narrow with double inner list being well developed but not oblique, postero-ventral part with submarginal shallow sockets or pits (conforming to tubercles on RV).

RVI ( Fig. 1E, G, J–L ). Both anterior and posterior margins subequally rounded, ventral margin sinuous at mid-length, submarginal selvage anteriorly, anterior calcified inner lamella wide, posterior calcified inner lamella narrow with two inner lists, postero-ventral part with c.18–20 prominent tubercles.

A1 ( Fig. 2A–B ). Seven-segmented, first segment with one short dorso-subapical seta (reaching tip of next segment) and two long ventro-apical setae. Second segment slightly wider than long, with one short dorso-apical seta (reaching half of next segment) and Rome organ. Third segment bearing two setae: one long dorso-apical (reaching beyond tip of penultimate segment) and one short ventro-apical setae (reaching slightly beyond half of next segment). Fourth segment with two long dorsal setae and two short ventral setae (both reaching slightly beyond tip of next segment). Fifth segment dorsally with two long setae, ventrally with two (one long, one short) setae, short one reaching slightly beyond tip 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 aesthetasc ya c. length of last four segments, length of short seta slightly less than half of that of aesthetasc ya.

A2 ( Fig. 2C–E ). Basal segment with two proximal setae and one long ventro-apical seta. Exopodite with three (one long, two short) setae, long one reaching slightly beyond half of penultimate segment. First endopodal segment with five very long (reaching far beyond tips of terminal claws) and one short natatory setae, length of the shortest seta reaching three fourth 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–G3), G1 and G2 large, G2 strongly serrated apically with concave apex, G3 slender claw, aesthetasc y2 long (not reaching tip of terminal segment), z1–z3 setae long, Z1 slightly larger than other z setae, z2 longest (beyond tip of claws G1–G3); this segment medially with two subequally long dorsal setae, four ventral setae of unequal length (t1–t4), one t seta clawlike appearance. Terminal segment distally with two serrated claws (GM and Gm), length of Gm c. ¾ of that of GM; medially with short g seta and ventral aesthetasc y3, length of aesthetasc y3 c. half of accompanying seta.

MD- PALP ( Fig. 2F ). First segment with two large setae (S1 and S2), one long and slender seta, and a short, smooth α-seta. Second segment dorsally with three unequal long apical setae, shortest seta reaching tip of next segment; ventrally with group of three long hirsute setae, one shorter hirsute seta and plumose, cone-shaped β-seta with pointed tip. Penultimate segment consisting of three groups of setae: dorsally with group of four unequal, long, subapical setae; laterally with apical γ-seta and three further apical smooth setae, the former slightly plumose (length c. 2.4 times of terminal segment); ventrally with two subapical setae, one long (reaching beyond tip of terminal segment), one short (c. half of terminal segment). Terminal segment bearing three claws and two shorter setae, largest claw appearing strongly robust with hairy ending.

MX 1 ( Fig. 3B ). With two-segmented palp, basal segment of palp dorsally with group of six long, unequal apical setae; ventrally with one long subapical seta (reaching slightly beyond tip of terminal segment). Terminal segment elongated (length c. 2 times of width), apically with three claws and two setae. Large bristles on endites claw-like, with hirsute ending and spatula-shaped apex, number of large bristles on first to third endites being 1, 1, 2, respectively. Sideways-directed bristles on first endite short, subequal in length.

T1 ( Fig. 3C–D ). Protopodite with two unequally short a-setae, b-, c- and d-setae absent, distally with 12 hirsute apical setae of unequal length. Endopodite weakly built palp with one very long, hirsute seta and two unequally shorter apical setae, length of shortest one less than ¼ of long one.

T2 ( Fig. 4A–B ). With d2 seta (d1 absent). Second segment with long e-seta (length c. ¾ of penultimate segment). Penultimate segment divided, proximal segment bearing long f-seta (reaching beyond tip of terminal segment), distal segment with short apical g-seta (reaching tip of terminal segment). Terminal segment with two (one dorsally, one ventrally) apical h1 and h3 setae (length of the former less than ¼ of claw, the latter short) and serrated claw (h2) with slightly bifurcated tip, length of h2 longer than that of penultimate segment.

T3 ( Fig. 4C ). A cleaning limb. First segment with subequal long d1, d2, dp setae. Second segment with long apical e-seta (reaching half of next segment). Third segment with short f-seta (not reaching tip of segment). Terminal segment with an apical pincer and one reflexed subapical seta, length of the latter slightly shorter than that of third segment.

CR ( Fig. 4D ). Reduced, flagellum-like with triangular base, laterally with short subapical seta, length of long seta c. 1.7 times of that of ramus and c. 3.8 times of that of short subapical seta.

Male

Unknown.

Figures

Fig. 1. Thaicypridopsis longispinosa sp. nov., ♀♀. A. LVe (MSU-ZOC.257). B. RVe (idem). C. CpD (MSU-ZOC.259). D. Valve surface (MSU-ZOC.257). E. Muscle scars of RV (MSU-ZOC.258). F. LVi (idem). G. RVi (idem). H. Posterior part of LVi (idem). I. Anterior part of LVi (idem). J. Anterior part of RVi (idem). K–L. Posterior part of RVi (idem). Scale bars: A–C, F–G = 100 µm; D, L = 10 µm; E = 13 µm; H–K = 58 µm.

Fig. 2. Thaicypridopsis longispinosa sp. nov., ♀♀. A. A1 (MSU-ZOC.264). B. Rome organ of A1 (MSU-ZOC.257). C. A2 (idem). D. Distal segment of A2 (idem). E. Claw G2 of A2 (idem). F. Md-palp (MSU-ZOC.263). Scale bars: 50 µm.

Fig. 3. Thaicypridopsis longispinosa sp. nov., ♀♀. A. Md-coxa (MSU-ZOC.257). B. Mx-1 (MSU- ZOC.264). C. T1 (idem). D. Endopodite of T1 (idem). Scale bars: 50 µm.

Fig. 4. Thaicypridopsis longispinosa sp. nov., ♀♀. A. T2 (MSU-ZOC.257). B. Distal part of T2 terminal claw (idem). C. T3 (idem). D. CR (MSU-ZOC.264). Scale bars: A, C = 50 µm; B, D = 20 µm.