Ozestheria quinlanae, Schwentner & Hethke, 2025

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 : 114-117

Ozestheria quinlanae sp. nov.

urn:lsid:zoobank.org:act:C0BAAA4E-FB1D-4EAE-B0DB-79059E20534E

Fig. 36

Diagnosis

Ozestheria quinlanae sp. nov. is characterized by a long condyle and a very narrow occipital notch; carapace ornamentation dorsally on carapace punctate to finely reticulated (may appear granular), in following growth bands intensely anastomosing lirae forming within growth band, lirae become longer, slightly less anastomosing and more pronounced with progressing growth bands; male rostrum with straight to weakly convex anterior margin, apex rounded with nearly rectangular angle, ventral margin convex; female rostrum with straight or weakly undulating anterior margin, apex rectangular and drawn out into acute tip, ventral margin nearly straight to convex; 15–16 (male) or 15–19 (female) antenna I lobes reaching to antenna II flagellomeres VIII–X (male) or V–VII (female); 13–14 (male) or 14–15 (female) antenna II flagellomeres; 21 complete thorax segments; 14–18 telsonic spines, most spines small and conical with usually two larger spine interspersed, posterior spines aciculate; 5–9 furcal setae.

Differential diagnosis

Ozestheria quinlanae sp. nov. can be differentiated from many other species of Ozestheria by the narrow occipital notch and long condyle in combination with the carapace ornamentation (dominated by punctate ornamentation dorsally on carapace, transitioning to distinct, subparallel lirae during ontogeny), except from O. cancellata comb. nov., O. minor comb. nov., O. typica comb. nov., O. fuersichi sp. nov., O. marthae sp. nov., O. selmae sp. nov., O. radiata sp. nov., O. bourkensis sp. nov., O. jonnae sp. nov., O. barcaldinensis sp. nov., O. ngamurru sp. nov., O. beleriandensis sp. nov., O. rincewindi sp. nov., O. glabra sp. nov., O. pilbarensis sp. nov. and O. weeksi sp. nov., and differentiating these species can be difficult. Ozestheria minor , O. typica , O. bourkensis , O. selmae , O. radiata , and O. beleriandensis can be differentiated by having at least the posterior half of the telsonic spines long, elongate and aciculate. Ozestheria quinlanae differs from most of the abovementioned species by the low number of telsonic spines (14–18); O. glabra has fewer telsonic spines (but this appears to be a growth defect) and O. barcaldinensis , O. marthae and O. jonnae have similarly low numbers, but differ in the shapes of the male and female rostrum.

Etymology

The species is named in honor of Kirsty Quinlan (Department of Biodiversity, Conservation and Attractions), who kindly provided a large collection of Western Australian specimens of Ozestheria , which led to the discovery of many new species, including this one.

Type material

Holotype

AUSTRALIA – Western Australia • ♂; Lake Bryde, Pingrup ; 33°21′11″ S, 118°49′22″ E; 6 Feb. 2012; D.J. Cale leg.; WAM C77988 .

Paratypes

AUSTRALIA – Western Australia • 1 ♂, 1 ♀; same data as for holotype; WAM C80227 , C80226 • 1 ♀; same data as for holotype; NHMW-ZOO-CR-29001 .

Additional material (not examined)

AUSTRALIA – Western Australia • 1 empty carapace; same data as for holotype; WAM C80228 .

Type locality

Western Australia, Lake Bryde, Pingrup, 33°21′11″ S, 118°49′22″ E.

Description

Males

CARAPACE ( Fig. 36a, c–d). Length 6.0– 6.7 mm (HT: 6.7 mm), height 3.7–4.1 (HT: 4.1 mm). Coloration orange-brown to dark brown, crowded growth bands lighter. 26–30 (HT: 30) growth lines, 17–24 (HT: 24) widely spaced and 6–9 (HT: 6) crowded.

CARAPACE SHAPE. Dorsal margin straight, distinct dorso-posterior corner. Posterior margin broadly rounded, suboval, supracurvate to equicurvate (b/H 0.43–0.50, HT: 0.50). Ventral margin widely rounded. Umbo position submedian (Cr/L 0.25–0.28, HT: 0.28).

CARAPACE ORNAMENTATION ( Fig. 36e–g). Larval valve granular or punctate (under SEM finely reticulated). Following growth bands punctate, shallow, intensely anastomosing lirae forming between punctae (under SEM lirae intermittent); lirae becoming more pronounced and less anastomosing in growth bands of later ontogenetic stages. Crowded growth bands with short, irregular lirae. Concentric ridges shallow. Setae mostly spiniform, few filiform setae interspersed, preferentially preserved on the ventral part of carapace (setal pores in single line along all growth lines under SEM).

HEAD ( Fig. 36i). Condyle long, distally acute; occipital notch very narrow. Condyle with weak anterobasal hump. Margin between condyle and ocular tubercle concave. Ocular tubercle weakly developed, forming obtuse, nearly rectangular (~90–110°) angle with rostrum. Anterior margin of rostrum straight to weakly convex (HT: weakly convex).Apex rounded, nearly rectangular. Ventral margin of rostrum convex. Naupliar eye subtriangular, anteriorly rounded, sometimes very small. Antenna I long with 15–16 lobes (HT: 16), reaching to antenna II flagellomeres VIII–X (HT: X). Antenna II with 13–14 flagellomeres (HT: 14).

THORAX. 21 (HT: 21) segments, all thoracopod-bearing. Most segments with spine-bearing dorsal extensions with numerous spines and setae.

THORACOPOD III (only WAM C77988; Fig. 36l). Endite I short and curved dorsally. Endites II–V broad, decreasing in size. Endite V palp two-segmented, basal segment subequal to endopod. Exopod ventral extension longer in extension to endopod, dorsal extension wide, narrowing distally, overreaching epipod. Epipod long, cylindric.

TELSON ( Fig. 36k). 14–18 spines (HT: 18). First (anterior) spine enlarged. Most spines short, thin, conical, subequal in length; a few (usually 2) slightly larger spines interspersed; most posterior spines thinner and aciculate, but not enlarged. Dorsal margin straight. Right terminal claw more strongly curved than left.

FURCA ( Fig. 36k). Proximally with dorsomedial longitudinal row of 5–9 (HT: 9) setae, row ending distally in a single conical spine. Distal part ⅔ of furcal length, with numerous small denticles.

Females Overall appearance as in males. Carapace ( Fig. 36b) length 6.6–8.0 mm, height 4.0– 5.1 mm; 22–40 growth lines, 17–24 widely spaced and 5–16 crowded; Cr/L 0.24–0.25 and b/H 0.46–0.48. Anterior margin of rostrum straight or undulating; apex rectangular, drawn out into acute tip; ventral margin nearly straight to convex ( Fig. 36j). Antenna I with 15–19 small lobes, lobes smaller than in males; reaching to antenna II flagellomeres V–VII. Antenna II with 14–15 flagellomeres. 21–22 segments, 21 thoracopod-bearing and none to one posterior limbless segment not reaching dorsal margin. Telson with 14–16 dorsal spines; left and right terminal claws equally curved. Furca with 7 setae, distal part ½ of furca length.

Distribution ( Fig. 36m)

Ozestheria quinlanae sp. nov. is known from a single locality in southwestern Western Australia.

Remarks

Because only few specimens were available, the morphological variability of the species is not well characterized. The carapace shape of Ozestheria quinlanae sp. nov. ( Fig. 6) is distinct from that of most other species and overlaps fully with those of O. marthae sp. nov., O. weeksi sp. nov. and partly with those of O. timmsi sp. nov., O. setifera sp. nov., O. jonnae sp. nov. (marginally), O. selmae sp. nov., O. cancellata comb. nov., and O. pilbarensis sp. nov.