Anguillanella callawaensis Perina and, 2019

Perina, Giulia, Camacho, Ana I., Huey, Joel, Horwitz, Pierre & Koenders, Annette, 2019, The role of allopatric speciation and ancient origins of Bathynellidae (Crustacea) in the Pilbara (Western Australia): two new genera from the De Grey River catchment, Contributions to Zoology 88 (4), pp. 452-497 : 477-484

Anguillanella callawaensis Perina and

Camacho sp. nov. (figs. 6,7,8–9) Zoobank: urn:lsid:zoobank.org:act:2399400E-4AA2-4697-80D6-0925B1DAD43E

Type locality. Bore CA 0008, Callawa Ridge, De Grey River Catchment, Pilbara, Western Australia (see Appendix 3 for borehole coordinates).

Material examined

Holotype. WAMC57418 , male, permanent slide, bore CA0008 , 24 July 2009, Bell (stygo net haul).

Allotype. WAMC57370 , female, permanent slide, bore CA0157 , 10 July 2009, Bell (stygo net haul).

Paratypes. WAMC57258 , female, permanent slide, Western Australia, Pilbara , bore CA0006 , 13 June 2009, Bell & Ridley (stygo net haul) ; WAMC57260 , female, 100% ethanol, Western Australia, Pilbara, bore CA0006 , 13 June 2009, Bell & Ridley (stygo net haul) ; WAMC57262 , female, 100% ethanol, Western Australia, Pilbara, bore CA0006 , 13 June 2009, Bell & Ridley (stygo net haul) ; WAMC57263 , sex not recorded, whole specimen for DNA, Western Australia, Pilbara, bore CA0006 , 26 April 2008, Bell & Eberhard (stygo net haul) ; WAMC57264 , sex not recorded, whole specimen for DNA, Western Australia, Pilbara, bore CA0006 , 26 April 2008, Bell & Eberhard (stygo net haul) ; WAMC57266 , male, permanent slide, Western Australia, Pilbara, bore CA0008 , 09 July 2009, Bell (stygo net haul) ; WAMC57267 , male, permanent slide, Western Australia, Pilbara, bore CA0008 , 09 July 2009, Bell (stygo net haul) ; WAMC57269 , female, 100% ethanol, Western Australia, Pilbara, bore CA0008 , 22 July 2009, Bell (stygo net haul) ; WAMC57270 , female, 100% ethanol, Western Australia, Pilbara, bore CA0008 , 22 July 2009, Bell (stygo net haul) ; WAMC57271 , female, whole specimen for DNA, Western Australia, Pilbara, bore CA0008 , 22 July 2009, Bell (stygo net haul) ; WAMC57273 , female, permanent slide, Western Australia, Pilbara, bore CA0011 , 23 July 2009, Bell (stygo net haul) ; WAMC57274 , sex not recorded, whole specimen for DNA, Western Australia, Pilbara, bore CA0011 , 23 July 2009, Bell (stygo net haul) ; WAMC57275 , male, permanent slide, Western Australia, Pilbara, bore CA0011 , 23 July 2009, Bell (stygo net haul) ; WAMC57277 , female, 100% ethanol, Western Australia, Pilbara, bore CA0011 , 12 June 2009, Bell & Ridley (stygo net haul) ; WAMC57278 , male, whole specimen for DNA, Western Australia, Pilbara, bore CA0011 , 12 June 2009, Bell & Ridley (stygo net haul) ; WAMC57280 , female, permanent slide, Western Australia, Pilbara, bore CA0012 , 31 May 2009, Bell & Barnet (stygo net haul) ; WAMC57281 , female, whole specimen for DNA, Western Australia, Pilbara, bore CA0012 , 31 May 2009, Bell & Barnet (stygo net haul) ; WAMC57283 , female, whole specimen for DNA, Western Australia, Pilbara, bore CA0013 , 09 July 2009, Bell (stygo net haul) ; WAMC57285 , male, permanent slide, Western Australia, Pilbara, bore CA0014 , 09 July 2009, Bell (stygo net haul) ; WAMC57286 , female, whole specimen for DNA, Western Australia, Pilbara, bore CA0014 , 09 July 2009, Bell (stygo net haul) ; WAMC57288 , female, permanent slide, Western Australia, Pilbara, bore CA0021 , 31 May 2009, Bell & Barnet (stygo net haul) ; WAMC57289 , female, whole specimen for DNA, Western Australia, Pilbara, bore CA0021 , 31 May 2009, Bell & Barnet (stygo net haul) ; WAMC57290 , female, whole specimen for DNA, Western Australia, Pilbara, bore CA0021 , 31 May 2009, Bell & Barnet (stygo net haul) ; WAMC57371 , female, 100% ethanol, Western Australia, Pilbara, bore CA0157 , 10 July 2009, Bell (stygo net haul) ; WAMC57373 , female, 100% ethanol, Western Australia, Pilbara, bore CA0160 , 09 July 2009, Bell (stygo net haul) ; WAMC57374 , juvenile, whole specimen for DNA, Western Australia, Pilbara, bore CA0160 , 09 July 2009, Bell (stygo net haul) ; WAMC57375 , juvenile, whole specimen for DNA, Western Australia, Pilbara, bore CA0160 , 09 July 2009, Bell (stygo net haul) ; WAMC57377 , female, 100% ethanol, Western Australia, Pilbara, bore CA0099 , 13 June 2009, Bell & Ridley (stygo net haul) ; WAMC57378 , female, 100% ethanol, Western Australia, Pilbara, bore CA0099 , 13 June 2009, Bell & Ridley (stygo net haul) ; WAMC57379 , male, permanent slide Western Australia, Pilbara, bore CA0099 , 13 June 2009, Bell & Ridley (stygo net haul) ; WAMC57380 , female, permanent slide Western Australia, Pilbara, bore CA0099 , 13 June 2009, Bell & Ridley (stygo net haul) ; WAMC57414 , female, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57415 , female, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57416 , sex not identifiable, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57417 , female, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57419 , female, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57420 , male, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57421 , female, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57422 , female, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57423 , male, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57424 , female, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57425 , male, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57426 , juvenile, permanent slide Western Australia, Pilbara, bore CA0008 09 July 2009, Bell (stygo net haul) ; WAMC57657 , male, permanent slide, Western Australia, Pilbara, bore CA0124 , 14 June 2009, Bell & Ridley (stygo net haul) ; WAMC59191 , female, whole specimen for DNA, Western Australia, Pilbara, bore CA0124 , 14 June 2009, Bell & Ridley (stygo net haul) ; WAMC59192 , sex not recorded, whole specimen for DNA, Western Australia, Pilbara, bore CA0124 , 14 June 2009, Bell & Ridley (stygo net haul) ; WAMC59193 , female, whole specimen for DNA, Western Australia, Pilbara, bore CA0124 , 14 June 2009, Bell & Ridley (stygo net haul) ; WAMC59194 , male, permanent slide, Western Australia, Pilbara, bore CA0057 , 23 July 2009, Bell (stygo net haul) ; WAMC59195 , male, permanent slide, Western Australia, Pilbara, bore CA0057 , 23 July 2009, Bell (stygo net haul) ; WAMC59196 , female, whole specimen for DNA, Western Australia, Pilbara, bore CA0057 , 23 July 2009, Bell (stygo net haul) ; WAMC59197 , female, whole specimen for DNA, Western Australia, Pilbara, bore CA0057 , 23 July 2009, Bell (stygo net haul); Abbreviations used: Th, thoracopod; A.I, antennule; A.II, antenna; Md, mandible, Mx.I, maxillule and Mx.II maxilla.

Description (based on adults)

Body. Total length of holotype and allotype 1 mm. Total length of males 0.7–1 mm, and females 0.8–1. mm. Body elongated; almost cylindrical, nearly eight times as long as wide; segments slightly widening towards posterior end. Head slightly longer than wide. Pleotelson with one plumose dorsal seta on either side. All drawings are of the holotype and allotype except: paragnath in fig. 6I, and labrum in fig. 6J.

Antennule (fig. 6A). Seven-segmented; length of first three segments slightly longer than the last four; first segment is the longest, then sixth and seventh, as well as second and third, of similar length; fourth small and fifth very small; inner flagellum small and trapezoidal; setation as in fig. 6A; one and two aesthetascs on segments sixth and seventh respectively.

Antenna (fig. 6B). Seven-segmented; as long as the first six segments of A.I; first four segments almost as long as the last three ones; fifth (third of endopod) very small, without setae; terminal segment is the longest; first, fourth and sixth segments similar in length and about 0.8 times as long as seventh segment; setal formula: 0/1+exp/2+0/1+0/0/2+0/5; exopod about twice as long as second segment, with two terminal setae, one smooth and one bifurcated sensory seta; ventromedial seta absent.

Labrum (fig. 6J, L). Almost square, with smooth free edge, and with two small lobes, more or less developed, on the distal part.

Paragnath (fig. 6I, K). Almost rectangular, strong long claw on distal part with thick setation, distal ventral section slightly dilated.

Mandible (fig. 6E–H). Palp with three segments, terminal segment with two long and strong equal barbed claws, more or less cylindrical without expansions (fig. 6E, F). Masticatory part (fig. 6G, H): pars incisiva (incisor process) with two teeth; processus incisivus accessorius with one tooth and one seta-like tooth; pars molaris with two dentate structures, parallel to main axis of teeth: first structure (closest to processus incisivus accessorius) with four teeth, and second structure bulbous with three to five small denticles.

Maxillule (fig. 6C). Proximal endite with four setae; distal endite with six teeth, four with denticles and two setae-like, and three plumose setae on the outer margin of endite.

Maxilla (fig. 6D). Four-segmented; setal formula 7, 4, 5, 5.

Thoracopods I-VII (fig. 7A–G). Epipod present on Th I to VII. Th I coxa with a long and strong plumose seta; basipod with two smooth setae. One-segmented exopod, shorter than endopod on all thoracopods; exopod reaches about the middle of the third segment of endopod in all thoracopods; it bears four barbed setae on Th I, Th VI and Th VII, two terminal, one dorsal and one ventral; and five barbed setae on Th III to V. Exopod of thoracopos I to VI with tuft of setules on ventral margin (on dorsal margin too on thoracopod I). Endopod with four segments in all thoracopods, setal formulae (number of setae on basipod in brackets):

Th I: (2) 3+0/2+1/2+0/3

Th II: (1) 2+0/2+1/2+0/3

Th III-IV-V: (1) 2+0/2+1/1+0/3

Th VI: (1) 1+0/0+1/0+0/2(1)

Th VII: (1) 0+0/0+1/0+0/2(1)

Male thoracopod VIII (fig. 8A–D). Small, rectangular and compact, with one lobe (outer lobe) on penial region (latero external part), almost trapezoidal very well developed and larger than the small triangular posterior projection (P. pr.). Small frontal projection (Fr. pr) integrated in penial region does not exceed the outer lobe and the basipod. Basipod vertical with big medial crest on distal end (bigger than O. lb.); endopod small, rectangular, with one short seta; exopod big, with simplified morphology and dilated on distal end, with two terminal setae, and with relatively square base and distal part curved outwardly, almost perpendicular to the main axis of basipod. The latero-internal view (fig. 8A–B) shows the relationship between basipod, exopod and endopod: distal end of basipod bears the endopod, concealed by the crest, and proximal end of basipod embedded near the base of the small penial region.

First pleopod (fig. 8F). Two segmented, first segment with one long seta; second segment with five setae, two distal of similar length and three subdistal unequal setae.

FemaleallotypethoracopodVIII (fig. 8E). Coxa without setae; basipod almost square; one small ramus, half of the size of basipod, with two setae (one thick and very long); very large epipod, about 2.5 times length of basipod.

Female allotype Th I-VII. Number of segments of endopods and exopods as in male holotype. Number of setae on segments of endopod and basipod differs from male holotype. Setal formulae of allotype (number of setae of basipod in brackets at the start):

Th I: (2) 3+0/2+1/2+0/3

Th II: (1) 2+0/2+1/2+0/3

Th III: (1) 1+0/2+1/1+0/3

Th IV-V: (1) 2+0/2+1/1+0/3

Th VI- VII: (1) 0+0/0+1/0+0/2(1)

Uropods (fig. 8H). Sympod 1.8 times longer than endopod, rectangular, about 1.5 times longer than wide, with four spines: first two distal spines smallest, almost half the length of endopod; third one as long as endopod; and fourth (proximal spine) two-third the length of third spine, but longer than first two distal ones. Endopod with spinous projection on distal outer corner, twice as long as exopod, bearing two strong claws (“uropodial claws” sensu Delamare Deboutteville & Serban, 1973) (distal claw 1.5 times longer than proximal claw); one “special seta” (“X”, which would correspond to the first claw on Bathynella according to Delamare Deboutteville & Serban, 1973); one plumose seta near the base on the ventral edge; one long terminal and one short subterminal seta, ventrally located. Exopod with four setae: two medial setae and two terminal (one very long and thick and the other one short and thinner).

Pleotelson (fig. 8G). With one long, plumose dorsal seta on either side.

Furcal rami (fig. 8G, H). Small, almost square, bearing five spines; dorsal spine as long as second and fourth, third longer than second and first twice the length of second spine.

Variability

The number of setae on segments of thoracopod endopod and second segment of pleopod vary; pleopod can have five to eight setae on second segment and the same specimen can have left setal formula different from right side. Spines on furca can have different size compare to the holotype; in some specimens the dorsal spine is half of the size of the second spine, and spine duplication can result in six spines on furca (fig. 9).

Etymology

The genus name comes from the Latin translation of Eel creek (Eel = Anguilla), which separates Callawa from Cundaline ridge. Substantive in opposition. The species name derives from the Callawa ridge where the species was collected.