Ozestheria berneyi ( Gurney, 1927 )

Schwentner, Martin & Hethke, Manja, 2025, Revision of the Australian Ozestheria Schwentner & Richter, 2015 (Crustacea: Branchiopoda: Spinicaudata) fauna, with the descriptions of 27 new species, European Journal of Taxonomy 992, pp. 1-172 : 26-31

Ozestheria berneyi ( Gurney, 1927)

Figs 9–10

Estheria berneyi Gurney, 1927: 61–64 , figs 2–3.

Eocyzicus berneyi – Brtek 1997: 44.

Caenestheria berneyi – Richter & Timms 2005: 346 .

Ozestheria sp. M – Schwentner et al. 2015a: figs 2, 6. — Hethke et al. 2023: fig. 10.

Ozestheria cf. berneyi (M) – Schwentner et al. 2020: figs 1–2.

Ozestheria berneyi – Rogers 2020: 23 .

Diagnosis

Ozestheria berneyi is characterized by a short condyle and wide occipital notch; a rounded ventral carapace margin; carapace ornamentation with polygonal reticulations on larval valve and early growth bands, following growth bands with reticulations dorsally and nodular lirae ventrally (lirae increase in length in later growth bands); male rostrum anterior margin weakly convex, apex rounded with acute angle (~60–90°), ventral margin concave; female rostrum anterior margin weakly convex to straight, apex pointed and drawn out with acute angle (~70–90°), ventral margin weakly concave; 12–19 (males) or 11–17 (female) antenna I lobes reaching to antenna II flagellomeres III–X (male) or III–IV (female); 10–15 (male) or 11–14 (female) antenna II flagellomeres; 23–24 complete thorax segments; 14–29 telsonic spines, spines mostly small, conical and subequal in size and spacing, 1–3 larger spines interspersed; 5–13 furcal setae.

Differential diagnosis

Ozestheria berneyi can be easily distinguished from most other Australian species of Ozestheria by the combination of its carapace shape and ornamentation (combination of reticulations and lirae), the pointed male rostrum apex and the telsonic spination (many small spines with 1–3 larger spines interspersed), except from O. fuersichi sp. nov. and O. gemina sp. nov. Ozestheria gemina has a longer condyle and the carapace ornamentation lacks the polygonal reticulations dorsally within growth bands in mid-carapace. Ozestheria fuersichi is smaller (carapace length 3.7–5.1 mm), has a nearly straight ventral carapace margin, carapace ornamentation stronger dominated by lirae (lacking polygonal reticulations on mid carapace), and the female rostrum has a concave anterior margin.

Type material

Syntype AUSTRALIA – Queensland • 1 ♂; Longreach ; Apr. 1922; R. Gurney leg.; raised from dried mud by Gurney, mud collected probably in 1921 or 1922 by F.L. Berney; BMNH1929.3.14.2 .

Gurney described a male and a female; only the male is stored at the Natural History Museum London; the fate of the female is unknown; the male syntype is probably a young adult (the carapace is short, nearly translucent and with few crowded growth bands, the claspers are relatively weakly developed) and the head is detached from the body and damaged.

Other material examined

AUSTRALIA – New South Wales • 3 ♂♂, 2 ♀♀; highway past Bourke, next to Lake Lauradale ; 29°50′29.1″ S, 145°37′26.1″ E; 18 Feb. 2010; M. Schwentner, C. Sieves and B.V. Timms leg.; AM P.82573 , P.82574 , P.91164 to P.91166 • 1 ♂, 4 ♀♀; Bloodwood Station, Lower Crescent pool ; 29°32′34.5″ S, 144°51′31.6″ E; 19 Jan. 2010; M. Schwentner and B.V. Timms leg.; AM P.91167 , P.91168 , P.91171 to P.91173 • 1 ♀; Bloodwood Station, Vosper Pool ; 29°32′03.9″ S, 144°50′37.7″ E; 19 Jan. 2010; M. Schwentner and B.V. Timms leg.; AM P.91170 • 1 ♀; budgery pool ; 29°23′02.2″ S, 144°49′00.2″ E; 20 Jan. 2010; M. Schwentner and B.V. Timms leg.; AM P.91181 • 1 ♂; claypan-like W of Engonia ; 29°18′32.8″ S, 145°44′06.9″ E; 21 Jan. 2010; M. Schwentner and B.V. Timms leg.; P.91169 . – South Australia • 1 ♂; old small dugout 105 km E of Marla; 27°10′00.2″ S, 134°33′07.2″ E; 11 Mar. 2011; M. Schwentner and B.V. Timms leg.; AM P.91179 . – Queensland • 2 ♂♂, 2 ♀♀; 2 km E of Led Nappers crossing ; 29°31′41.7″ S, 146°08′30.1″ E; 21 Jan. 2010; M. Schwentner and B.V. Timms leg.; AM P.91175 to P.91178 • 2 ♀♀; borrow pit , Lochern National Park; 24°05′57.6″ S, 143°13′41.1″ E; 10 Jan. 2010; M. Schwentner and B.V. Timms leg.; AM P.91147 , P.91148 • 1 ♀; yapunyah pool 36 km N of highway; 27°49′09.6″ S, 144°09′26.5″ E; 28 Feb. 2011; M. Schwentner and B.V. Timms leg.; AM P.91163 • 1 ♂; rocky quarry 83 km N of highway; 27°27′31.4″ S, 144°22′12.2″ E; 28 Feb. 2011; M. Schwentner and B.V. Timms leg.; AM P.91180 • 2 ♂♂; marsilea swamp 2 km E of Boulia; 22°54′40.7″ S, 139°55′30.0″ E; 4 Mar. 2011; M. Schwentner and B.V. Timms leg.; AM P.91154 , P.91155 • 2 ♂♂, 1 ♀; old borrow pit 8 km E of Boulia; 22°55′44.6″ S, 139°58′23.7″ E; 4 Mar. 2011; M. Schwentner and B.V. Timms leg.; AM P. 91156 to P.91157 , P.91159 • 1 ♂; old borrow pit 8 km E of Boulia; 22°55′44.6″ S, 139°58′23.7″ E; 4 Mar. 2011; M. Schwentner and B.V. Timms leg.; NHMW-ZOO-CR-28487 • 2 ♂♂; dead shrub old borrow pit , 113 km S of Mount Isa; 21°34′21.0″ S, 139°11′58.4″ E; 4 Mar. 2011; M. Schwentner and B.V. Timms leg.; AM P.91149 , P.91150 .

Additional material (not examined)

AUSTRALIA – Queensland • 1 ♂; 2 km E of Led Nappers crossing ; 29°31′41.7″ S, 146°08′30.1″ E; 21 Jan. 2010; M. Schwentner and B.V. Timms leg.; AM P.91174 • 2 ♂♂; yapunyah pool 36 km N of highway; 27°49′09.6″ S, 144°09′26.5″ E; 28 Feb. 2011; M. Schwentner, C. Sieves and B.V. Timms leg.; AM P.91161 , P.91662 • 1 ♂, 2 ♀♀; marsilea swamp 2 km E of Boulia; 4 Mar. 2011; M. Schwentner and B.V. Timms leg.; AM P.91151 to P.91153 • 1 ♂; old borrow pit 8 km E of Boulia ; 22°55′44.6″ S, 139°58′23.7″ E; 4 Mar. 2011; M. Schwentner and B.V. Timms leg.; AM P.91160 .

Type locality

Australia, Queensland, Longreach.

Description

Males

CARAPACE ( Fig. 9a, c–d, g ). Length 4.3–7.8 mm (ST: 4.3 mm, mean: 5.6 mm), height 2.6–4.9 mm (ST: 2.6 mm, mean: 3.5 mm). Coloration light-yellow-brown/ocher to darker reddish-brown or semitranslucent (ST), outer margin lighter. 17–63 (ST: 17, mean: 31) growth lines, 15–22 (ST: 16, mean: 17) widely spaced and 3–48 (ST: 3, mean: 14) crowded; ST with 3 more closely spaced growth bands from 7 th growth line, followed by 4 widely spaced growth bands and a second crowded region (probably a secondary growth phase).

CARAPACE SHAPE. Dorsal margin straight, distinct dorso-posterior corner. Posterior margin broadly rounded, weakly suboval (more circular than in many other species), equicurvate (b/H 0.48–0.53, ST: 0.48, mean: 0.51). Ventral margin broadly rounded. Umbo position anterior (Cr/L 0.20–0.25, ST: 0.22, mean: 0.22).

CARAPACE ORNAMENTATION ( Fig. 9e–f, h–k ). Larval valve and first few growth bands with shallow reticulations forming mainly irregular pentagons or hexagons. From mid-dorsal carapace, medium reticulations turning into pronounced lirae ventrally within growth bands (under SEM punctae or secondary reticulations between main reticulations and lirae apparent and lirae nodular). Lirae becoming longer and more pronounced on successive growth bands, but irregular reticulations persist dorsally on all wide growth bands or appear as anastomosing lirae posteriorly on the carapace. Some lirae intermittent, not reaching concentric ridge, or intercalating ventrally on growth bands. Crowded growth bands very narrow, without apparent ornamentation (intermittent lirae visible under SEM); secondary growth phase of ST with widely spaced, irregular and intermittent lirae. Concentric ridges raised, lined dorsally by minute nodules in moniliform rows. Filiform and short, stout setae ( Fig. 9l ); usually 4–5 spiniform setae followed by one filiform seta (in many individuals only few and mostly filiform setae preserved); under SEM a single irregular row of setal pores along all growth lines.

HEAD ( Fig. 10a, c, e ). Condyle short and weakly protruding, distally rounded; occipital notch wide. Condyle lacking anterobasal hump. Margin between condyle and ocular tubercle straight to slightly concave. Ocular tubercle weakly developed (rarely stronger developed), forming obtuse angle of varying degrees (mostly ~110°–140°, but ranging from close to rectangular to nearly straight; ST: ~110° [derived from Gurney 1927]) with rostrum. Anterior margin of rostrum weakly convex (sometimes nearly straight). Apex rounded, acute (~60–90°). Ventral margin of rostrum concave. Naupliar eye elongated, subtriangular to subrectangular with rounded margins. Antenna I long with 12–19 lobes (ST: 18; mean: 15), reaching to antenna II flagellomeres III–X (ST: VIII; mean: VIII). Antenna II with 10–15 flagellomeres (ST: 12; mean: 13).

THORAX. 23–25 (ST: 23; mean: 24) segments, 23–24 (ST: 23; mean: 23) thoracopod-bearing and none to one (ST: none) posterior limbless segment not reaching dorsal margin. Dorsal extensions with numerous short, stout spines; these increase in size and decrease in numbers posteriorly.

THORACOPOD III (only P.91159; Fig. 10f ). Endite I short and curved dorsally.Endites II–V broad, decreasing in size. Endite V palp two-segmented, basal segment subequal in length to endopod. Exopod ventral extension subequal in extension to endopod, dorsal extension wide, narrowing distally, overreaching epipod. Epipod long, cylindric.

TELSON ( Fig. 10g –i ). 14–29 spines (ST: 19, mean: 21). First (anterior) spine enlarged. Spines conical, spines on posterior ~1/5 slightly thinner and more drawn out (aciculate). Most spines small (compared to telson size) and subequal in size and spacing, few (usually 1–3) slightly larger spines interspersed in anterior ⅔ of telson (largest situated in the central part of the telson). Anteriormost spines not arranged along dorsal margin but slightly lateral. Dorsal margin nearly straight, anteriorly sometimes weakly convex. Right terminal claw more strongly curved than left.

FURCA ( Fig. 10g –i ). Proximally with dorsomedial longitudinal row of 6–13 (ST: 7, mean: 9) setae, row ending distally in a single conical spine. Distal part ½–⅔ of furcal length, with numerous small denticles.

Females

Overall appearance as in males. Carapace ( Fig. 9b ) length 4.5–7.3 mm (mean: 5.7 mm), height 2.8– 4.5 mm (mean: 3.5 mm); 15–27 (mean: 21) growth lines, 14–22 (mean: 16) widely spaced and 1–10 (mean: 5) crowded; Cr/L 0.19–0.23 (mean: 0.20) and b/H 0.47–0.52 (mean: 0.50). Anterior margin of rostrum weakly convex to straight ( Fig. 10b, d ); apex with acute angle (~70–90°), pointed, drawn out into protruding tip; ventral margin weakly concave. Antenna I with 11–17 small lobes (mean: 14), lobes smaller than in males; reaching to antenna II flagellomeres III–IV (mean: III). Antenna II with 11–14 flagellomeres (mean: 12). 23–25 (mean: 24) thoracopod-bearing segments, 23–24 (mean: 23) thoracopod-bearing and none to one posterior limbless segment not reaching dorsal margin. Telson with 17–26 (mean: 20) dorsal spines; left and right terminal claws equally curved. Furca with 5–10 setae (mean: 8), distal part ½–¾ of furcal length.

Distribution ( Fig. 10j )

Ozestheria berneyi is widely distributed in the (semi)arid regions of eastern and central Australia. It has been most recorded from northern New South Wales and southern and western Queensland (e.g., catchments of the Georgina River and the central Cooper Creek) but also from northern South Australia.

Remarks

Schwentner et al. (2015a) suggested that either O. sp. M or N might represent O. berneyi . By studying the type material, we were able to identify O. sp. M as O. berneyi ; O. sp. N is being described as O. gemina sp. nov. There are several strong arguments for O. sp. M representing O. berneyi : the carapace ornamentation (including polygonal reticulations dorsally within growth bands and the intermittent nodular lirae), and the length of the condyle (which is more elongated in O. gemina ); also, O. sp. M was collected close to the type locality of O. berneyi . Only the carapace shape is a notable outlier (Supp. file 1_3.5 & 4.8). The original drawings of the male and female carapace by Gurney (Supp. file 1_4.6–4.7) were classified as O. sp. N (= O. gemina ; probability 97.4% and 99.7%, typicality scores 0.89 and 0.05). The available syntype, however, was classified as O. sp. D1+D2 (= O. rubra ; probability 87.7%, typicality score 0.00) and with 8.4% probability (0.00 typicality) as O. sp. N (= O. gemina ). Our geometric morphometric analyses ( Fig. 5 ) were restricted to adult-only datasets, and the length of the specimens of the O. sp. M training set ranged between 4.5 mm and 7.8 mm, while the studied syntype specimen is 4.3 mm in length and, thus, probably a relatively young adult that does not show the characteristic very narrow growth bands in the crowded carapace region, which has a significant effect on carapace shape by extending the posteroventral margin.

Figures

Fig. 9. Ozestheria berneyi (Gurney, 1927). a–d. Carapace. a. Male (P.91159). b. Female (P.91156). c. Male, dorsal view (only left valve shown; P.91159). d. Carapace male syntype (BMNH1929.3.14.2). e–f. Carapace ornamentation of male syntype (BMNH1929.3.14.2; positions marked by rectangles in d). e. Dorso-posterior carapace. f. Ventral carapace. g. Male (P.91157), SEM. h–k. Carapace ornamentation of male paratype (P.911157; positions marked in g by rectangles), SEM. h. Dorsal carapace. i. Posterior carapace. j. Dorsomedian carapace. k. Ventral carapace. l. Carapace setation female paratype (P.91156). Scale bars: a–d, g =0.5 mm; e–f, i–k =0.1 mm; h =0.02 mm.

Fig. 10. Ozestheria berneyi (Gurney, 1927). a–e. Head (antennae not shown). a. Male, original drawing by Gurney (1927). b. Female, original drawing by Gurney (1927). c. Male (P.91159). d. Female (P.91156). e. Male (P.91157), SEM. f. Male, third right thoracopod (P.91159). g–i. Telson. g. Male, original drawing by Gurney (1927). h. Male (P.91157), SEM. i. Male (P.91159). j. Distribution map (gray star indicates the type locality; produced in ArcMap 10.7; see caption Fig. 7 for sources). Scale bars: c–f, h–i=0.2 mm.

Fig. 5. Morphometrics of short-condyled species. Scores on upper PC1 and PC2 of Fourier shape coefficients of 248 outlines, including 233 new individuals and 15 historic type specimens, four of which are drawings ofOzestheria elliptica (Sars, 1897),O. lutraria (Brady, 1886) andO. berneyi (Gurney, 1927). One of the drawings of O. berneyi corresponds to the studied syntype. The names used by Schwentner et al. (2015a) to identify genetically delimited species (e.g., C, D etc.; extended for the newly identified species, e.g., X1) are provided. New specimens are represented by convex hulls, type specimens by data points. lower. Mean shape of each species, calculated based on up to 73 individuals per species.