Kimberleybathynella callani Perina & Camacho, 2025

Perina, Giulia, Camacho, Ana I., Morgan, Liesel, Lawrie, Angus, Floeckner, Stephanie & Guzik, Michelle T., 2025, New species of Atopobathynella, Kimberleybathynella and Hexabathynella (Parabathynellidae, Bathynellacea) from the arid zones of Western Australia, Zootaxa 5655 (1), pp. 1-103 : 57-60

publication ID	https://doi.org/10.11646/zootaxa.5655.1.1
publication LSID	lsid:zoobank.org:pub:4411E6C2-D4C5-4340-AF6B-FDDBB0F7E1A1
DOI	https://doi.org/10.5281/zenodo.15822711
persistent identifier	https://treatment.plazi.org/id/0399C326-FF83-FFE9-53BB-05CBFE8DF9C1
treatment provided by	Plazi
scientific name	Kimberleybathynella callani Perina & Camacho
status	sp. nov.

Treatment

Kimberleybathynella callani Perina & Camacho , sp. nov.

urn:lsid:zoobank.org:act:13F97DFF-B056-432D-ACB4-C2024926BD6E

( Figures 23 View FIGURE 23 & 24 View FIGURE 24 )

Material examined. Holotype male. AUSTRALIA: Western Australia: Ord River, Kimberley, Murrays Bore (pump sample), 17°38'43.6374"S, 127°55'40.0584"E, 3 November 2016, S. Callan, M. O’Connell, ( WAMC 79091 — BES2077 b— BMR08553 View Materials , permanent slide). GoogleMaps

Diagnosis. K. callani sp. nov. belongs to a group of Kimberleybathynella species that have inner flagellum on antennula very small; tooth of ventral edge of mandible absent; distal endite of maxillula with six claws; epipod of thoracopod I present; two setae on exopod of thoracopods I to VII; two setae on exopod and endopod of uropod; anal operculum not protruded. K. callani sp. nov. differs from all the other Kimberleybathynella by having two setae on all exopods of the thoracopods and no ventromedial seta on the exopod of the uropod. The sequenced specimen differs from all the other Kimberleybathynella species sequenced by COI = 18.9–25.1% ( Table 3) and 12S = 17.6% (S.E. = 0.4%) with K. ordensis sp. nov.

Description male holotype (WAM C79091). Body length of 0.76 mm. Body eight and a half times as long as maximum width, elongated, almost cylindrical, segments slightly widening and lengthening towards posterior end of body.

Antennula ( Fig. 23A View FIGURE 23 ): six-segmented. The first, second and sixth articles similar in length and 1/4 longer than the other three, which are similar in length. Antennal organ absent. Very small inner flagellum almost, rectangular. Article five and six with three terminal aesthetascs each. Antennula setation as in Fig. 23A View FIGURE 23 .

Antenna ( Fig. 23B View FIGURE 23 ): two-segmented, longer than the first article of the antennula; first article square without setae, second article with one smooth subterminal and three terminal setae, of which two smooth of different length and one plumose which is the longest.

Labrum ( Figs. 23C View FIGURE 23 ): almost flat, with 15 main teeth on free edge, six and seven on each side, and two centrals.

Paragnaths: absent.

Mandible ( Fig. 23D View FIGURE 23 ): pars incisiva with three teeth; pars molaris with five claws, with the two distal ones denticulate and the two proximal ones joined together; tooth of ventral edge absent. Mandibular palp with a very small article with one long distal seta not exceeding pars incisiva.

Maxillula ( Fig. 23E View FIGURE 23 ): proximal endite with four unequal claws; distal endite with four denticulated claws and two smooths; three smooth subterminal setae of different lengths on the distal outer margin.

Maxilla ( Fig. 23F View FIGURE 23 ): four-segmented, first and second articles partially fused, setal formula 2, 3, 11, 1.

Thoracopods I to VII ( Fig. 24A–G View FIGURE 24 ): length gradually increasing from ThI to III, last four similar in size. Epipod present in thoracopods I to VII about 2/3 length of the corresponding basipod. Basipods with one smooth, distolateral seta shorter than the first article of the endopod in ThI to II and longer than the first article of the endopod in ThIII to VII. Exopod one-segmented in all thoracopods, shorter than corresponding two first articles of the endopod in all thoracopods, with two barbed terminal setae, with the internal one slightly longer than the external one in ThI , three times longer in ThII and VI, two times longer in ThIII to V, and two and half times longer in VII; internal seta of the exopod extending beyond the distal end of the fourth article of the endopod in ThIII to VII. Endopod four-segmented, first article short with one seta on ThI and no seta on the rest of thoracopods, second and third articles long and similar in length; second article with one plumose external seta in all thoracopods and one inner smooth seta only on ThI ; third article of ThI with one small inner seta, and one outer seta on ThII to VII; fourth article very reduced with two strong claws of different length on all thoracopods, ThI with one additional seta. Setal formula of endopods:

ThI 1+0/1+1/1+0/3(1)

ThII to VII 0+0/0+1/0+1/2

Thoracopod VIII ( Figs. 23G, H View FIGURE 23 ): compact, rectangular shape. Penial region with massive protopod, outer lobe rectangular and defined at base in latero-external view; exopod almost square with small teeth on distal end and not defined at base, endopod rounded with one seta, similar in size to exopod, endopod and exopod integrated in basipod; basipod not defined at base, with inner distal end rounded not reaching the outer lobe.

Pleopod I: not seen.

Pleopods II to V: unknown, segments used for DNA extraction.

Uropod ( Fig. 24H View FIGURE 24 ): sympod over three times the length of the endopod (excluding the dagger-shaped structure) and almost six times as long as wide, with eight spines, the most distal one slightly longer than others. Endopod almost as long as exopod, with internal row of small “spinules” in the middle, drawn out distally into a long dagger-shaped structure with terminal setules, and with distolateral angle bearing two barbed setae of different length. Exopod with two terminal barbed setae (inner one shorter) and no ventromedial seta.

Pleotelson ( Fig. 24I View FIGURE 24 ): with two very small plumose lateral setae (one on each side); anal operculum not protruded.

Furca ( Fig. 24I View FIGURE 24 ): each ramus almost square, with four barbed spines which increase in length from the proximal to the distal one, which is two times longer than the first. Two dorsal plumose setae on each ramus, the inner one very short and the outer one exceeds the tip of the most distal spine.

Female of K. callani is unknown.

Distribution and remarks. K. callani sp. nov. has been collected from one bore about 18 km south of the Ord River, in the Kimberley ( Fig. 2 View FIGURE 2 ). The distribution could possibly extend beyond Murrays bore (Biologic Environmental Surveys unpublished data), however all material collected in the area was not available for this study. This species is similar to K. pleochaeta and K. ordensis sp. nov., however it differs from them by the number of setae on the exopod of thoracopods (only two), the number of spines on furca (four), and the absence of a ventromedial seta on the exopod of the uropod. K. callani sp. nov. is the only species that does not have the “tooth ventral edge” between the pars molaris and pars distalis of the mandible ( Fig. 23D View FIGURE 23 ), male ThVIII rectangular instead of hemispherical, ventro-medial seta of uropodal exopod absent. Unfortunately, the body segments of the pleon were used for DNA extraction, so it was not possible to determine if it had additional pleopods on pleomere II to V. K. callani sp. nov. was collected about six km south from K. ordensis sp. nov. ( Fig. 2 View FIGURE 2 ) and the two species are sister taxa in the molecular phylogeny ( Fig. 5 View FIGURE 5 ).

Etymology. The name of the species is dedicated to Shae Callan, one of the collectors of the species and a colleague.

Genus Hexabathynella Schminke, 1973

Type species. Hexabathynella pauliani ( Delamare Deboutteville, 1953) .

Parabathynella valdiviana Delamare Deboutteville, 1953

Other species: see Table 7

Amended diagnosis (after Cho and Schminke 2006).

Body elongated and cylindrical. Antennula six-segmented. Second antennular segment sexually dimorphic. Antenna five-segmented. Labrum flat. Pars molaris of mandible consisting of five spines. Maxilla three-segmented. Thoracopod VII absent. Exopod of thoracopod I one-segmented; that of thoracopods II–VI one or two-segmented. Male thoracopod VIII massive, basipod bearing a seta and being drawn out in a chitinous projection, with elongated endopod and triangular or square exopod. Endopod with one or two distal setae. Sympod of uropod with spines: distal spine longer than other spines. Inner terminal seta of uropodal exopod shorter than outer one. Furcal rami with three spines.