Heterocypris salina ( Brady, 1868 )

Heterocypris salina ( Brady, 1868) View in CoL

Figs 10 View Figure 10 , 11 View Figure 11 , 12 View Figure 12 , 13 View Figure 13

Cypris salina Brady, 1868: 368–369, pl. 26, figs 8–13. View in CoL

Cyprinotus fretensis Brady & Robertson, 1870 View in CoL : figs 48, 49 ( Meisch and Broodbakker 1993).

Cyprinotus salina ( Brady, 1868): Müller 1900: 76, pl. 16, figs 1, 2, 10, 12.

Heterocypris salina ( Brady, 1868), nov. comb.: Klie 1932: 588. View in CoL

Cyprinotus salinus ( Brady, 1868): Wagner 1957: 30–31, pl. 9, figs 1–6. View in CoL

Cyprinotus salinus ( Brady, 1868): Jordan et al. 1962: 76, 77, pl. I, figs 6, 7; pl. V, figs 57–61; pl. VIII, figs 80, 82, 83. View in CoL

Cyprinotus salinus ( Brady, 1868): Devoto 1965: 332, fig. 26. View in CoL

Cyprinotus salinus ( Brady, 1868): Diebel and Pietrzeniuk 1975: 1213, pl. VII, figs 5, 6. View in CoL

Cyprinotus salinus ( Brady, 1868): Diebel and Pietrzeniuk 1978: 90, pl. 24, figs 5, 6. View in CoL

Heterocypris salina salina ( Brady, 1868): Freels 1980: 28, pl. 3, figs 1–6. View in CoL

Heterocypris salina ( Brady, 1868): Meisch 2000: 354–357, fig. 148. View in CoL

Material examined.

Germany • 10 dissected females, (size RV length = 1012–1107 µm, height = 629–652 µm; LV length = 1098–1133 µm, height = 671–694 µm). Botanical Garden , TU Braunschweig; M. Bonilla-Flores leg. China • 2 females from Taro Co, STP ( TIP 11-84 ) (size RV length = 1068–1061 µm, height = 660–667 µm; LV length = 1079–1092 µm, height = 741–741 µm) ; • 2 females from Taro Co ( TIP 11-86 ) ( RV length = 1011–1146 µm, height = 633–732 µm; LV length = 1024–1151 µm, height = 616–693 µm) ; • 1 female from Xuru Co, STP ( TIP 12 - H 55) (size RV length = 960 µm, height = 569 µm; LV length = 983 µm, height = 618 µm); P. Frenzel leg.

Diagnosis.

(Adult female, Figs 10 View Figure 10 , 11 View Figure 11 ) (adapted from Meisch 2000 and Kubanç et al. 2007): valves compressed and triangular in the dorsal region. RV smaller than LV, LV overlapping RV. RV has row denticles on anterior and posterior margins in external view, with broad inner lamella and inner list (Fig. 10 A 1, A 3, A 4, B 1, B 3, B 4 View Figure 10 ). LV with a broad inner lamella, anteriorly with inner list, in the posteromedial region with a slight fold (Fig. 10 A 2 – B 2 View Figure 10 ). Both valves display a brown coloration pattern, characterized by a pair of lighter stripes (Fig. 11 B 1, B 2 View Figure 11 ). Normal pores on the internal valve surface with simple apertures. The upper lip presents dense pseudochaetae laterally, just above the mouth opening. Female genital lobes with an oval shape, with no discernible projection at the intersection, but the shape of the apex is truncated, and an interlacing projection at the intersection forms a ring.

Dimensions.

Adult females, RV ranges: length = 970–1194 µm, height = 577–755 µm; LV ranges: length = 989–1189 µm, height = 603–724 µm.

Valves.

Laterally, dorsal side arched. RV has a broad inner lamella with small denticles along the anterior and posterior margins. LV displays a broad inner lamella accompanied by an inner list. Normal pores on the internal valve surface with simple apertures (Fig. 10 A 5, A 6, B 5, B 6 View Figure 10 ). Similarly, multiple normal rimmed pores are present on the external valve surface, with a single bristle (Fig. 11 A 7, A 8, B 7, B 8 View Figure 11 ). Some striations were observed for organisms from Germany (Fig. 11 B 7 View Figure 11 ).

Description of soft parts.

(Figs 12 View Figure 12 , 13 View Figure 13 ): Antennule (Fig. 12 A View Figure 12 ). Seven-segmented: segment I with two long setose setae on the posterodistal side and one short seta on the anterodorsal region. Segment II with a short seta on the anterior side. Segment III carries two distal setae, with the anterodorsal seta reaching segment VII. Segment IV bears two long anterodorsal setae and two short posterodistal setae. Segment V features four long setae in the distal region. Segment VI with an α-setae in the distal part, with four long setae. Segment VII presents three long setae distally and one aesthetasc ya with 65 µm length, roughly twice as long as the terminal segment (31 µm).

Antenna (Fig. 12 B View Figure 12 ). Five-segmented: coxa has two short hairy setae and one smooth short seta. Basis with a ventrodistal long seta. Exopod long seta as long as the first endopodal segment, which bears a segmented aesthetasc Y, a stout ventroapically seta, one short and five long natatory setae in the apical dorsal part. The second endopodal segment has four t-setae and two aesthetascs (y 1 in the posteromedial part and y 2 in the posterodistal part). This segment also bears two medial setae, and distally three long, slender setae (z) and three claws (G 1, G 2, and G 3). Claws G 1 and G 3 are approximately equally long, while G 2 is shorter. The terminal segment presents two claws (GM and Gm), and the aesthetasc y 3. Exopod long seta (140 µm length) longer than the first (119 µm) and second (96 µm) endopodal segment, respectively; the exopod long seta is approximately 1.46 × the length of the second endopodal segment.

Upper lip (Fig. 13 A View Figure 13 ). Measurements on the upper lip were taken as follows: l — length (245 µm), h — height (64 µm), hp — position of the maximum height (168 µm), in accordance with Karan-Žnidaršič and Petrov (2014). Dense pseudochaetae were present laterally, just above the mouth opening. Rake-like organs are formed by eight teeth on the right, and nine on the left.

Mandibular coxa (Fig. 12 C View Figure 12 ) with seven teeth, the largest one with small setae on its ventral part. Teeth three, four, and seven lack setae between them.

Mandibular palp (Fig. 12 D View Figure 12 ). Four-segmented: the first segment bears two setose setae and one smooth seta, and an additional α-seta. The second segment has four setose setae, one long smooth seta, and one short setose β-seta on the inner part, and three smooth setae on the outer part. The third segment features eleven setae; four long smooth setae, with one thick γ-seta. In the most distal region, there are three short, setose setae and three smooth setae. The last segment has three setose setae in the distal region and one smooth seta.

Maxillula (Fig. 12 E View Figure 12 ). Maxillular palp two-segmented, the first one bears a long, smooth seta with four long and smooth distal setae, the second segment of the palp is subrectangular with four smooth setae. First endite with eight setae in distal part, and two setae in the basal region. Seven setae in second endite. The third endite has two serrated Zahnborsten, plus five smooth setae.

T 1 (Fig. 12 F View Figure 12 ). With two setae a, one b, and one d. Exopod with six hirsute rays, protopod with 13 setose distal setae. Endopod with three distal setae, h 1 and h 3 longer than h 2.

T 2 (Fig. 13 B View Figure 13 ). Five-segmented: segment I with a short seta d 1. Second segment bears a long anterodistal e-seta. Third segment with a distal setose f-seta. Segment four with a distally located g-seta with a shorter seta. Fifth segment with three h-setae; the claw-shaped seta h 2 with dentition. The length of the second endopodal segment measures 95 µm, representing 61 % of the length of the claw which measures 156 µm.

T 3 (Fig. 13 C View Figure 13 ). Four-segmented: first segment bears a short, smooth seta d 1. In the distal region, with a long d 2 - seta, and a setose dp-seta. Second segment with a setose distal e-seta. Third segment in the distal part (fused 4 th segment) has a small h 1 - seta, seta h 2 is striated, and seta h 3 long.

Uropodal ramus (Fig. 13 D View Figure 13 ) with an elongated shape and two distal claws – Ga (137 µm), exceeding Gp (97 µm) in length – plus one shorter setose Sp (80 µm). Additionally, with a smooth Sa seta, shorter than Sp, and two caudal ramus attachments.

Female genital lobes (Fig. 13 E View Figure 13 ). Oval and elongated shape, curvature of lobes; shape of apex is truncated, without a beak, and an interlacing projection at the intersection forms a ring.

Reproduction.

Only asexual populations were found in Germany and STP. Males were recorded from Crete, Greece ( Petkowski et al. 2000).

Distribution.

Widespread distribution ( Meisch 2000).

Habitat.

Heterocypris salina is an eurytopic species, tolerant to high conductivity, typical of shallow and temporary ponds ( Meisch 2000). Furthermore, according to our limnological data (Table 1 View Table 1 ) and previous publications, the species is found in fresh, brackish, and saline waters ( Ganning 1971), and alkaline and oxygenated waters (average 6.5 mg / l). Upper salinity limits are given as 8.6 ‰ ( Vesper 1975) and even up to 20 ‰ ( Griffiths and Holmes 2000). It is also tolerant to organic pollution ( Mezquita et al. 1999).