Anaspides clarkei Ahyong, 2015

Ahyong, Shane T., 2016, The Tasmanian Mountain Shrimps, Anaspides Thomson, 1894 (Crustacea, Syncarida, Anaspididae), Records of the Australian Museum 68 (7), pp. 313-364 : 322-327

Anaspides clarkei Ahyong, 2015

Figs 5–8 , 35B–C , 36

Anaspides tasmaniae . —Lake & Coleman, 1977: 12–13, pl. 2. —Jarman & Elliot, 2000: fig. 4 (Wolf Hole), tab. 1 (part, Wolf Hole). — Clarke, 2000: 30; 2006, fig. 5.13–15. — Eberhard, 2001: 97. — Boulton et al., 2003: 48.

Anaspides sp. (telson ‘cave’ type). — Eberhard et al., 1991: 48 (Hastings and Ida Bay systems only).

Anaspides . —Gooderham & Tsyrlin, 2002: 73, unnumbered colour figure (Exit Cave).

Anaspides clarkei Ahyong, 2015: 596–597 , fig. 1A–D (type locality: Exit Cave, Ida Bay ).

Type material. HOLOTYPE: SAMA C6301 , ♂ (29 mm), Exit Cave , Ida Bay , 70 m asl, BS1848, coll. E. Hamilton Smith, 24 May 1969 . PARATYPES: SAMA C6302 , 1♀ (32 mm), Exit Cave , Ida Bay , 70 m asl, BS1848, coll. E. Hamilton Smith, 24 May 1969 ; AM P73045, 1 juv. ♀ (18 mm), Base Camp Tributary , Exit Cave, Ida Bay , 43°28.2' S 146°51'E, coll. S.Gersbach (#64631) ; TMAG G6033 , 1♀ (38 mm), Exit Cave (IB-120), Ida Bay Karst , rock pool in Skeleton Creek, coll. A. Clarke, 20 Jan 1998 .

Other material examined. Hastings Karst: AM P73047, 1♂ (28 mm), far end of Lake Pluto, Wolf Hole , above mud, 43°23.3'S 146°51.4'E, 998-23, coll. A. Clarke, 20 Sep 1998 ; AM P73046, 1♀ (31 mm), Lake Pluto, Wolf Hole , 43°23.3'S 146°51.4'E, above muddy substrate, 200 m asl, 998-22, coll. A. Clarke, 20 Sep 1998 ; QVM:10:47694, 1♀ (28 mm), Lake Pluto, Wolf Hole , 43°23.3'S 146°51.4'E, above muddy substrate, 200 m asl, 998-22, coll. A. Clarke, 20 Sep 1998 ; AM P99289, 1♂ (22 mm), 1♀ (23 mm), 1 juvenile ♀ (12 mm), Newdegate Cave (H-X7), Hastings Karst, 43°23.0'S 146°50.5'E, from pools in Mystery Creek streamway beyond Binney Chamber,1298-02, coll. A.Clarke, 1 Dec 1998 ; AM P99290, 1 indeterminate juvenile (shrivelled, poor condition,> 8 mm), Hell’s Half Acre streamway, 1.6 km into Newdegate Cave (H-X7), Hastings Karst , 43°23.0' S 146°50.5'E,from pools in Mystery Creek streamway beyond Binney Chamber, 1298-07, coll. A. Clarke, 1 Dec 1998 .

Ida Bay Karst : QVM 10 :49168, 3♀♀ (21–24 mm), Eastern Passage streamway of Little Grunt Cave and Exit Cave, 43°28.3'S 146°51.7'E, coll. S. Eberhard, Aug 1993 ; QVM 10 :13261, 3♀♀ (c. 19–31 mm), Little Grunt Cave (IB29), 43°28.3'S 146°51.7'E,coll. S. Eberhard, 17 Feb 1992 ; QVM 10 :13254, 1♀ (19 mm), 1 juvenile ♀ (14 mm), Exit Cave , Eastern Passage, 43°28.3'S 146°51.3'E, coll. S. Eberhard, 15 Feb 1992 ; QVM 10 :12248, 3 juvenile ♂♂ (9–19 mm), Loons Cave (IB2-7), Ida Bay Karst , 43°27.4'S 146°52.1'E, deep stream, 80 m asl, coll. S. M. Eberhard & J. Jackson, 10 May 1989 ; QVM 10 :12177, 2♀♀ (23–25 mm), 1 indet juv. (10 mm), Milkrun Cave (IB38-5), 43°28.3'S 146°51.3' E, 360 m asl, about 200 m from entrance, coll. S. Eberhard, 22 August 1985 ; TMAG G6487 , 1♀ (24 mm), Arthurs Folly (IB10), 43°27.3'S 146°52.3'E, stream, dark zone, 690-05,coll. A. Clarke, 24 Jun 1990 ; TMAG G6488 , 1♂ (23 mm), Cyclops Pot (IB57), pool at bottom of lower pitch, 190 m depth, 290-01, coll. D. Morgan & J. Butt for A. Clarke, 18 Feb 1990 ; TMAG G6486 , 1 juvenile ♂ (18 mm), 1♀ (21 mm), Revelation Cave (IB1), 43°27.8'S 146°50.3' E, from deep pool, base of underground shaft, 240 m asl , CV49 ,coll. A.Goede, 14 Jun 1969 ; QVM 10 :13230, 1♂ (24 mm), 2♀♀ (22–23 mm), Exit Cave , 43°24'S 146°52'E,tributary,coll. S. Eberhard, 15 Feb 1992 ; AM P82857, 1 juvenile ♀ (14 mm), Exit Cave , 43°28.2'S 146°51.0' E, trickle at side entrance from IB161, Bobs Hole, in twilight zone , JHB T0701 , coll. J.H. Bradbury, 7 Mar 1997 ; AM P99291, 1♀ (21 mm), Exit Cave (IB-14), pool near Ballroom passage, 700 m into cave, 43°28.6'S 146°51.3'E, 202-11, 14 Feb 2002 ; AM P99292, 1♂ (20 mm), 1 juv. ♀ (21 mm), Exit Cave ,riffle zone near Ballroom Passage junction, 43°28.6'S 146°51.3'E, dark zone, 397-63, coll. A. Clarke, 7 Mar 1997 ; AM P99293, 1 juvenile ♂ (18 mm), 2 juvenile ♀♀ (18–19 mm), Exit Cave (IB-120), Lost Squeeze Passage, pools, 194-04, coll. A. Clarke, 20 Jan 1998 ; AM P99294, 2♀♀ (24 mm), Exit Cave (IB14), Base Camp Tributary, c. 1.75 km into Exit Cave,202-19,coll. A. Clarke, 14 Feb 2002 ; TMAG G6489 , 3 juvenile ♂♂ (15–22 mm), 1♀ (21 mm), Base Camp Tributary , c. 1.75 km into Exit Cave (IB-14), 193-112, coll. A. Clarke, 29 Jan 1993 ; TMAG G6485 , 2♂♂ (21–24 mm), 3♀♀ (20–29 mm), Exit Cave , Devil’s Stovepipe,pool at bottom of shaft,dribble system, at rock base with pools,“no pigment regeneration after 4 weeks in lab”, coll. A. Goede & B. Collins, 2 Mar 1969 ; TMAG G6484 , 1♀ (32 mm), Exit Cave , 50 m downstream of “Waddle ‘n’ Splosh”, coll. Laimonis Kavalieris, 23 January 1973 ; TMAG G6494 , 3 juvenile ♂♂ (22–25 mm), 5♀♀ (23–32 mm), Exit Cave , pool at base of shaft near Keller’s Squeeze, 43°28.1'S 146°50.7'E , CV42 , coll. A. Goede & A. Keller, 29 Mar 1969 ; TMAG G6490 , 1♀ (20 mm), Exit Cave (IB14), 20 m upstream from site of monitoring probe, dark zone, 996-05, coll. L. Gardner & J. Hammond for A. Clarke, 7 Sep 1996 ; TMAG G1287 , 2♀♀ (20–23 mm), Exit Cave ,coll. W.D.Williams, 1 Jun 1968 ; ZSRO 385 , 1 juvenile ♀ (15 mm), Bradley-Chesterman Cave (IB6), c. 75 m upstream from entrance, 43°27.7'S 146°51.8'E, coll. A. Clarke, 5 Mar 2006 .

Description. Eyes with cornea pigmented or unpigmented, strongly reduced, narrower than stalk, shorter than one-fourth length of stalk; stalk with subparallel or slightly convergent margins.

Rostrum broadly triangular, almost equilateral, apex blunt.

Pleonites 1–5 unarmed, with sparsely setose pleural margins, rounded. Pleonite 6 posterior and posterolateral margins unarmed, setose. Pleonal sternites 3–5 with low, median processes between pleopod bases, bilobed and widest on sternite 3, bilobed on sternite 4, unilobate on sternite 5.

Telson length and width subequal to slightly longer than wide, widest proximally; lateral margins sinuous in dorsal outline, distally convergent; transition from lateral to posterior margin obtusely and bluntly angular to rounded; posterior margin bluntly angular to broadly rounded; posterior spine row with 4–15 (usually 6–8) stout, wellspaced spines, directed posteriorly, arrangement usually subsymmetrical, though frequently distinctly asymmetrical; proximalmost spines near posterior 0.25 of telson length.

Antennule inner flagellum about 0.2 × body length (26–28 articles in holotype); article 7 inner margin obtusely angled in adult males, with 4 (rarely 5) relatively short, slender, closely spaced clasping spines; outer flagellum 0.6–0.8 × body length (103–108 articles in holotype). Antennal flagellum 0.4–0.6 × body length (98 articles in holotype); scaphocerite ovate, lateral spine near distal one-fourth; apex slightly overreaching penultimate peduncular article.

Right mandibular incisor process with proximal tooth distally trifurcate.

Pleopods 1–2 (usually) or 3 with endopod in adults (occasionally with pleopod 3 endopod present on one side only). Adult male pleopod 1 distally widened, scoop-like, lateral margins expanded, obscuring retinacular lobe in lateral view.

Uropodal protopod dorsally unarmed; exopod with 2 or 3 movable spines on outer margin near position of partial diaeresis; exopod length about 3.5–4 times width, slightly wider than endopod, apex rounded, relatively narrow.

Measurements. Male (n = 20) 15–29 mm, female (n = 47) 9–38 mm, sex indeterminate (n = 2) 8–10 mm.

Remarks. The cave dwelling Anaspides clarkei is highly distinctive in having the posterior margin of the telson armed with few (4–15, usually 6–8) stout, well-spaced spines (versus a row of fine, closely-spaced spines), the strongly reduced cornea, and long outer antennular flagella that are distinctly longer than half the body length ( Figs 5 , 6 ). Anaspides clarkei also differs from adults of other congeners in lacking the endopod on pleopods 4 and 5, usually also pleopod 3. The endopod of pleopods 1–4, and usually also on pleopod 5, is present in adults of all other species of Anaspides . Although pleopodal endopod development is anamorphic in Anaspides , but in A. clarkei , the endopods do not develop beyond pleonite 3, usually pleonite 2. Similarly, the rostrum of other species of Anaspides becomes increasingly slender with age, but the rostrum of A. clarkei remains broad into maturity. Thus, the reduction in pleopodal endopods and broad rostrum in adults suggests that A. clarkei is, in some respects, paedomorphic.

The “cave-type” telson of A. clarkei , with few, stout wellspaced spines, superficially resembles that of A. eberhardi from caves in the Junee-Florentine karst system. Distinctions between the two species are outlined under the account of A. eberhardi . Despite the superficially similar telson spination to A. eberhardi , A. clarkei is most closely related to A. jarmani from the neighbouring surface localities, uniquely sharing similar male pleopod 1 morphology in which the retinacular lobe is obscured in lateral view, the presence of 4 (rarely 5) antennular clasping spines in adult males, and in the absence of pleonal spines. Anaspides clarkei and A. jarmani differ chiefly in the well-developed eyes in the latter, different telson spination (spines widely spaced in A. clarkei ), and absence of endopods on pleopods 4–5 (usually also absent on 3) in A. clarkei . Other distinctions between the two species are outlined under the account of A. jarmani . As in other species of the genus, the uropodal endopod in A. clarkei exceeds three-fourths the length of the exopod. The right uropodal endopod of the holotype of A. clarkei , however, is abnormally shortened ( Fig. 6B ), possibly as a result of damage or moult irregularities.

The arrangement of posterior telson spines of A. clarkei is usually only approximately symmetrical, contrasting with the highly degree of symmetry seen in A. eberhardi . Several specimens of A. clarkei have aberrant, distinctly asymmetrical telson spination, probably as a result of injury or moult irregularities (e.g., Fig. 8N,P,S ). A specimen (female, 32 mm, TMAG G6484; Fig. 8W–Y ) from “Waddle ‘n Splosh”, Exit Cave, is aberrant in having more numerous, somewhat asymmetrically developed, less widely spaced telson spines, and much more strongly reduced, almost flattened corneas; in other respects, including pleopodal endopod reduction, the specimen agrees with typical A. clarkei . Development of the male antennular clasping spines is sequential, with two or three present in juveniles, reaching the full complement of four spines in adults. Both sexes of A. clarkei appear to be mature by 19–25 mm.

Anaspides clarkei is known only from the Ida Bay and Hastings karst systems, exhibiting troglobitic adaptations in the significantly reduced cornea with degenerate ommatidial facets, reduction or absence of corneal and body pigmentation, and proportionally much longer antennular and antennal flagella, measuring distinctly more than half body length. General setal development in A. clarkei is uniform and resembles that of epigean forms, but body pigmentation differs between localities. Those from Ida Bay and Newdegate Cave (Hastings) are unpigmented or significantly de-pigmented, at most with diffuse body pigmentation; all have corneal pigmentation ( Fig. 35B ).As observed by Goede (1972) and Lake & Coleman (1977), however, specimens from Wolf Hole lack all body and corneal pigmentation ( Fig. 35C ). In addition to the complete loss of pigmentation, adults from Wolf Hole also differ slightly from Newdegate Cave and most Ida Bay specimens in the noticeably blunter, broader and more flattened posterior margin of the telson ( Fig. 8L–N ); additional material from Wolf Hole is required to determine the stability of this feature. The telson in Ida Bay and Newdegate specimens generally tapers more strongly and is more rounded distally, although some specimens from Milkrun Cave and Little Grunt Cave ( Fig. 8U,V ) approach those from Wolf Hole. In other respects, the Wolf Hole specimens agree well with those from other localities. The 28 mm male from Wolf Hole (AM P73047; Fig. 8J–L ) has five clasping spines on the left antennule, four on the right; other adult males have four clasping spines on both antennules. Wolf Hole is the most isolated locality at which A. clarkei occurs, being hydrologically separated from the Ida Bay system and neighbouring Newdegate Cave, as well as from epigean Anaspides . Some degree of subspecific or possibly even specific differentiation is plausible between Hastings and Ida Bay populations given the isolation of the respective karst systems. Anaspides listed from the Hastings and Ida Bay systems as “telson ‘cave’ type ” by Eberhard et al. (1991) are referrable to A. clarkei .

In both Hastings and Ida Bay systems, the closely related A. jarmani has entered subterranean waters (Newdegate Cave and Mystery Creek Cave, respectively). Both A. clarkei and A. jarmani are present in Newdegate Cave, but it is not presently known whether they are sympatric there or occur in different parts of the system.

Quarrying at Ida Bay since the Second World War, with attendant severe sedimentation and degraded water quality led to extinction of Anaspides from Bradley-Chesterman Cave. Closure of the quarry in 1992, however, followed by catchment rehabilitation saw Anaspides recolonize Bradley-Chesterman by December 1998 ( Eberhard, 1999, 2001), presumably from populations in other parts of the drainage such as Loon’s, Little Grunt, Arthurs Folly caves. The re-appearance of A. clarkei in Bradley-Chesterman Cave corroborates the supposition of subterranean continuity between Ida Bay cave subsystems ( Kiernan, 1993).

Distribution. Presently known only from Ida Bay and Hastings karst systems; 70–360 m asl.

Figures

Figure 5. Anaspides clarkei Ahyong, 2015, holotype male, 29 mm, Exit Cave, Ida Bay, SAMA C6301. Habitus, right lateral view. Scale 4.0 mm.

Figure 6. Anaspides clarkei Ahyong, 2015, holotype male, 29 mm, Exit Cave, Ida Bay, SAMA C6301. (A) cephalothorax, dorsal view; (B) pleonite 6, telson and right uropod; (C) pleonites 4–6 pleura, right lateral view; (D) right antennule; (E) right antenna; (F) labrum, anterior view;(G) right mandible; (H) right mandible incisor process;(I) paragnaths, anterior view; (J) right maxillule; (K) right maxilla; (L) pleopods 1–2, in-situ, ventral view. Scale:A–E, L = 2.0 mm; F–K = 0.7 mm.

Figure 7. Anaspides clarkei Ahyong, 2015.(A–O) Holotype male, 29 mm, Exit Cave, Ida Bay, SAMA C6301; (P–Q) paratype female, 32 mm, Exit Cave, SAMA C6302. (A) right thoracopod 1 (maxilliped); (B–H) right thoracopods 2–8; (I–J) right pleopod 1 endopod, lateral and ventral views; (K) right pleopod 2 endopod, lateral view; (L) right pleopod 3, anterior view; (M–O) pleonites 3–5 median sternal processes; (P–Q) female gonopore, right lateral and ventral views. Scale A–H, L–O = 2.0 mm; I–K = 1.0 mm.

Figure 8. Anaspides clarkei Ahyong, 2015. (A–C) juv. female, 15 mm, Bradley Chesterman Cave, Ida Bay, ZSRO; (D–F) female, 24 mm, Arthur’s Folly, Ida Bay, TMAG G6487;(G) female, 18 mm, Exit Cave, Ida Bay,AM P73045; (H–I) juv. female, 14 mm, Exit Cave, AM P82857; (J–L) male, 28 mm, Wolf Hole, Hastings, AM P73047; (M) female, 28 mm, Wolf Hole, QVM 10:47694; (N) female, 31 mm, Wolf Hole, AM P73046; (O) paratype female, 32 mm, Exit Cave, SAMA C6302; (P) paratype female, 38 mm, Exit Cave, TMAG G6033; (Q) female, 23 mm, Newdegate Cave, Hastings, AM P99289; (R) male, 22 mm, Newdegate Cave, AM P99289; (S) female, 19 mm, Revelation Cave, Ida Bay, TMAG G6486; (T–U) indet juv. (10 mm), female (25 mm), Milkrun Cave, Ida Bay, QVM 10:12177; (V) female, 31 mm, Little Grunt Cave, Ida Bay, QVM 10:13261; (W–Y) female, 32 mm, “Waddle ‘n splosh”, Exit Cave, TMAG G6484; (Z) female, 24 mm, Exit Cave, AM P99294. A, D, H, J, W, anterior cephalothorax; B, E, G, I, L, M–V, X, Z, telson; C, F, K, Y, scaphocerite. Scale:A–C, H–I, T = 0.5 mm; D–G, J–S, U–Z = 1.0 mm.

Figure 36. Distribution of Anaspides. Dubious Orford record of A. swaini indicated by “?”.

Figure35.(A) Anaspides tasmaniae (Thomson, 1893), female,Mt Wellington,specimen not preserved;(B) A.clarkeiAhyong, 2015, female, 24 mm, Eastern Passage streamway of Little Grunt Cave and Exit Cave, QVM 10:49168; (C) A. clarkeiAhyong, 2015, male, Lake Pluto, Wolf Hole, specimen not examined; (D) A. richardsoni sp. nov., female, Tarn Shelf, Mt Field, specimen not preserved; (E) A. richardsoni sp. nov., female, 32 mm, Kellys Pot, Mole Creek karst,TMAG G6463;(F) A. richardsoni sp.nov., female,35 mm, Marakoopa Cave, Mole Creek karst, specimen not preserved. Photo credits: A, Kristi Ellingsen, used under a Creative Commons Attribution-NonCommercial license (http://creativecommons.org/licenses/by-nc/2.0/); B, E, ©Stefan Eberhard; C, F, ©Arthur Clarke; D, ©Simon Grove, TMAG.