Hancockcandonopsis tamworthi, Karanovic, 2018

Karanovic, Ivana, 2018, A new Candonopsini (Ostracoda) genus from subterranean waters of New South Wales (Australia), Zootaxa 4379 (2), pp. 247-267 : 256-260

Hancockcandonopsis tamworthi sp. nov.

Figure 7–9

Type locality: Bore 93015, Peel River alluvial aquifer, Piallamore, Tamworth, New South Wales, 31°12’S 151°05’E, 06/12/2005, collector Peter Hancock.

Material examined. Holotype: male dissected on one slide (P. 100300) from the type locality.

Other material: Paratype female, disintegrated and on SEM stub from the type locality; one female dissected on one slide (P. 100301), from: Bore 30167, Peel River alluvial aquifer, Piallamore, Tamworth, New South Wales, 31°12’S 151°05’E, 15/10/2005, collector Peter Hancock

Etymology: The species is named after Tamworth town, situated in the near proximity to the collecting site.

Differential diagnosis. Carapace trapezoidal in lateral view, surface smooth; A1 7-segmented; second segment of male A2 subdivided; prehensile palps symmetrical and with strongly sclerotized bases of subterminal cuticular structures; d1-seta on L6 present; f-seta absent on both L6 and L7; hemipenis a-lobe with distal and lateral projections.

Description of male. Carapace trapezoidal in lateral view ( Figures 8A–C ). Dorsal margin flat medially, inclined towards anterior, and rounded towards posterior end. Anterior and posterior margins rounded, posterior narrower than anterior one. LV overlaps RV dorsally with pronounced flange. Ventral margin concave. Shell surface smooth and covered with long and dense sensilla, exiting from pores with lip margin. Inner calcified lamella wide anteriorly. Marginal pore canals short, except around mouth region, and not branching. Maximum L around 0.6 mm. Greatest H situated behind middle, equaling 50% of total L.

A1 ( Figure 8F ) 7-segmented. First segment with one anterior and 2 posterior setae. Second segment with one short anterior seta. Third segment with two short setae; fourth segment with one short anterior seta; fifth segment with one medium long anterior seta; sixth segment with two long and two short setae. Terminal segment with two long, one short seta and aesthetasc. Length ratio of 5 distal segments equaling 1.4: 1.1: 1: 1.4: 2.

A2 ( Figure 8G ) 6-segmented, with two segmented protopodite and 4-segmented endopodite. Exopod with one long and two short setae. Aesthetasc Y long, exceeding distal margin of first endopodal segment. First endopodal segment with one long seta postero-distally. Penultimate segment divided with male sexual bristles. z1-, and z2- setae transformed into claws, former half as long as latter; z-3 seta-like. G1- and G3-claws reduced, G2-claw long. Gm-claw long, GM-claw short.

Md-palp ( Figure 8H ) with short terminal segment. First segment anteriorly without any seta, posteriorly with two setae: plumose S1 and one additional smooth seta; S2 and α-seta not observed. Second segment with two setae anteriorly exceeding middle of the following segment; posteriorly with three pappose setae in the bunch, small βseta and one additional pappose seta. Penultimate segment anteriorly with almost equally long three posterior setae, distally with smooth γ-seta, and four setae postero-distally, of which one is very short, two of medium size and one longer and stouter. Terminal segment with broadly fused distal claw, one additional claw to its anterior side and one seta on its posterior side.

Mxl-palp ( Figure 8I ), same as in the previous species except that thin seta between two claws on terminal segment was not observed.

Rake-like organ ( Figure 8P ) with approximately 10 small teeth.

Prehensile palps almost symmetrical ( Figure 8M, N ), both with elongated bodies and medium long, curved finger. One of two subapical cuticular structures with well sclerotized base.

L6 ( Figure 8L ) 5-segmented. Basal seta (d1) present. First and third endopodal segments with one short seta each. Second segment bare, while penultimate segment with one short, distal seta. Terminal segment with two setae and one long claw.

L7 ( Figure 8O ) 5-segmented. Basal segment with all three setae (d1, d2, dp). Endopodal segment with e- and g-setae; f-seta absent. Terminal segment with three setae, h3-seta longest and hook-like distally, followed by h2- and h1-seta.

UR and attachment ( Figure 9A, B ). UR without posterior seta, anterior seta fallen off. L ratios between anterior margin, anterior claw, and posterior claw 2: 1.5: 1.

Hemipenis ( Figure 9E ), a-lobe with distal and lateral projections, rounded. b-lobe with flat distal margin and both inner and outer margins with small finger-like extensions.

Zenker-organ with 5+2 whorls of spines.

Description of female. Carapace ( Figures 7A , 8C, D, E ) similar to male. Surface same as in male ( Figure 7B– D ). L same as male.

A2 ( Figure 8J ) with only one t-setae present, and one seta antero-medially on second endopodal segment. z1- seta strong, but not claw-like; z2- and z3-setae not observed. G2-claw as long as all other claws.

L5 ( Figure 8K ) with one a-seta; b- and d-setae also present.

UR and attachment ( Figure 9C, D ). Anterior seta very short reaching only 1/7th of anterior claw. Attachment more branching than in male. L ratios between anterior uropodal ramus, anterior and posterior claws 1.7: 1.3: 1. Genital field rounded.

All other soft parts same as in male.

Figures

FIGURE 7. SEM of Hancockcandonopsis tamworthi gen. nov. sp. nov. Female: A—whole animal viewed from the right side (tilted); B—detail of the posterior end; C—detail of the anterior end; D—cuticular pore with seta on the surface.

FIGURE 8. Line drawings of Hancockcandonopsis tamworthi gen. nov. sp. nov. A–C, F–I, L–O, male (P.100300); D, E, J, K, female (P.100301): A—LV, inside view; B—LV, outside view; C—RV, inside view; D—whole carapace viewed form the right side; E—RV, inside view; F—A1 (not all setae on the terminal segment illustrated); G, A2; H—Md-palp; I—Mxl-palp; J—A2; K—L5; L—L6; M—right prehensile palp,N—left prehensile palps; O—L7. Scales = 0.1 mm.

FIGURE 9. Line drawings of Hancockcandonopsis tamworthi gen. nov. sp. nov. A, B, E, male (P.100300); C, D, female (P.100301): A—UR; B—UR attachment; C—UR and genital field; D—UR attachment; E—hemipenis.Scale = 0.1 mm.