Anaspides eberhardi, Ahyong, 2016

Ahyong, Shane T., 2016, The Tasmanian Mountain Shrimps, Anaspides Thomson, 1894 (Crustacea, Syncarida, Anaspididae), Records of the Australian Museum 68 (7), pp. 313-364 : 327-332

Anaspides eberhardi sp. nov.

Figs 9–12 , 36

Anaspides sp. (telson ‘cave’ type). — Eberhard et al., 1991: 48 (Junee-Florentine records only).

Type material. HOLOTYPE: QVM 10 :49169, ♂ (32 mm), Niggly Cave (JF-2), near Maydena, Junee-Florentine Karst, 42°42'S 146°31'E, coll. S. Eberhard, Aug 1993 . PARATYPES: QVM:2016:10:0001, 1♂ (30 mm), Niggly Cave (JF-2), collected with holotype ; QVM:2016:10:0002, 1♀ (32 mm), Niggly Cave (JF-2), collected with holotype ; TMAG G6479 , 1♂ (32 mm), 2♀♀ (28–34 mm), Niggly Cave ( JF2-1 ), 42°42'S 146°31'E ; QVM 10 :12917, 1♂ (31 mm), 2♀♀ (c. 25–33 mm), Cauldron Pot (JF-2), Maydena, Junee-Florentine Karst, 42°42.9'S 146°34.4'E, 720 m asl, Brew Ch, E series streamway, coll. S.M. Eberhard, 28 Jan 1990 ; TMAG G6492 , 1♀ (30 mm), Cauldron Pot (JF-2), Maydena, Junee-Florentine Karst, 42°42.9'S 146°34.4'E, 720 m asl, coll . R. Eberhard , 1 Feb 1985 .

Other material examined. (Junee-Florentine Karst). TMAG G6467 , 1 juv. ♂ (19 mm), 1♀ (43 mm), cave JF-104, at foot of Tiger Range , Florentine Valley, 42°33'S 146°25'E, underground stream, A. Goede, 9 Oct 1976 ; AM P99295, 1 juv. ♂ (shrivelled, poor condition, c. 13 mm), Welcome Stranger Cave (JF-229), 42°37.8'S 146°30.4'E, from TMAG G6469 , 1 stream , CV50 , coll. D. Maloney, 3 Apr 1971 ; TMAG G6470 , 1♂ (24 mm), 1 juv. ♂ (18 mm), Welcome Stranger Cave , 42°37.8'S 146°30.4'E, in stream , CV39 , coll. S. Eberhard, A.Richardson & R. Swain , 28 Oct 1984 ; TMAG G6471 , 2♀♀ (21–27 mm), Welcome Stranger Cave , 42°37.8'S 146°30.4'E,coll . R. Eberhard , 6Aug 1990 ; TMAG G6482 , 1♀ (35 mm), Porcupine Pot ( JF387 ), Florentine Valley, 42°40.9'S 146°30.2'E, 640 m asl , CV1 , coll. S. Eberhard, 10 Nov 1985 ; TMAG G6480 , 2♂♂ (29–32 mm), 2♀♀ (31–37 mm), Gormenghast Cave ( JF35-8 ), Florentine Valley, 42°41'S 146°30'E ; TMAG G6483 , 1♀ (c. 26 mm), Pendant Pot ( JF37 ), Florentine Valley, 42°41.4'S 146°30.0'E, 550 m asl , CV36 , coll . R. Eberhard , Apr 1984 ; TMAG G6472 , 1♀ (24 mm), Growling Swallet (JF-36), 42°41.4'S 146°30.0'E, 570 m asl , CV25 , coll. S. Eberhard, 29 Sep 1985 ; TMAG G6474 , 1 juv. ♀ (10 mm), Growling Swallet (JF-36), 42°41.4'S 146°30.0' E, at least 400 m depth,in stream, 590 m asl, coll. S. Eberhard, 11 Dec 1983 ; TMAG G6475 , 5♀♀ (27–47 mm), Junee Cave , Florentine Valley, 42°44.3'S 146°35.7'E, 340 m asl, coll. S. Eberhard, 3 Jan 1985 ; TMAG G6468 , 1♀ (31 mm), Settlement Cave , Florentine Valley , CV45 , coll. D. Maloney, 17 Apr 1971 ; TMAG G6477 , 1♀ (45 mm), Florentine Valley , cave, no other data, CV 48, Jun 1972 ; TMAG G6476 , 1♀ (c. 20 mm, very poor condition), Florentine Valley , cave, no other data, CV 47, Jun 1972 ; TMAG G6478 , 2♂♂ (17–18 mm), 2♀♀ (17–20 mm), Florentine Valley , unnamed cave, found in pool of standing water in cave passage which acts as a flood overflow , CV43 , coll. A. Goede, 2 Nov 1969 .

Description. Eyes with cornea pigmented, reduced, narrower than stalk, shorter than half length of stalk; stalk with subparallel or slightly convergent margins. Rostrum triangular, apex narrow, blunt.

Pleonites with sparsely setose pleural margins, rounded; Pleonites 1–3 unarmed. Pleonite 4–5 posterior tergal margins unarmed; pleura rounded, with 0–3 (usually 1) small spines and scattered setae. Pleonite 6 posterior margin with row of small spines, setose; posterolateral margin setose, rounded. 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 longer than wide, slender, triangular, widest proximally, lateral margins slightly sinuous in dorsal outline, distally strongly convergent on narrow apex; normally with 4 pairs of stout, graded, symmetrically arranged, wellspaced spines, anterior 3 pairs directed posterolaterally, distal pair directed posteriorly; occasionally with abnormal asymmetrical spination (3/4, 3/5 or 4/5 spines on either side); proximalmost spines near posterior 0.3–0.4 of telson length; occasionally with stout posteromedian spine and small dorsal median spine above posterior margin.

Antennule inner flagellum about 0.2 × body length (24–29 articles in holotype); article 7 inner margin obtusely angled in adult males, with 1 long, slender, clasping spine at proximal corner; outer flagellum 0.6–1.1 (usually 0.7–0.8) × body length (139 articles in holotype). Antennal flagellum 0.5–0.6 × body length (111 articles in holotype); scaphocerite elongate, ovate, lateral spine at distal one-third; apex not reaching midlength of distal peduncular article.

Right mandibular incisor process with proximal tooth distally trifurcate.

Pleopods 1–4 with endopod.Adult male pleopod 1 distally widened, scoop-like, lateral margins weakly expanded, not obscuring retinacular lobe in lateral view.

Uropodal protopod with 1–3 small dorsal spines; exopod with 1–3 movable spines on outer margin near position of partial diaeresis; exopod length 3.5–4 times width, slightly wider than endopod, apex rounded, relatively narrow.

Etymology. Named in honour of Stefan Eberhard, who collected the majority of specimens of this new species.

Measurements. Male (n = 12) 13–32 mm, female (n = 26) 10–47 mm.

Remarks. Anaspides eberhardi sp. nov., the second species of the genus with a “cave-type” telson, is most closely related to A. richardsoni , uniquely sharing the single antennular clasping spine in adult males ( Fig. 9D ). The two species are readily separated by the armature of the telson, with few, well-spaced spines in the new species (compared to the closely packed posterior spine row in A. richardsoni ), and absence of the pleopod 5 endopod in adults of A. eberhardi (rarely absent in A. richardsoni ). Moreover, the telson of A. eberhardi is distinctly more elongate and posteriorly tapering than any other species of the genus. Anaspides eberhardi also shows cave adaptations in corneal reduction, more elongate antennular flagella and body depigmentation. The eyes, however, remain pigmented and the corneas, although reduced compared to epigean forms, are comparatively larger than in the other obligate troglobite, A. clarkei . The telson of A. eberhardi is like that of A. clarkei , however, in having few, stout, widely spaced spines, rather than the fine, closely packed spine row of epigean forms. Anaspides eberhardi is readily distinguished from A. clarkei by the presence of one instead four (rarely five) antennular clasping spines in adult males, posterior denticles on pleonal pleura 5–6 (unarmed in A. clarkei ), a distinctly more elongate and more distally tapering telson in which the posterior spines extend anteriorly to the posterior one-third of the telson, rather than posterior one-fourth in A. clarkei ; and presence of the pleopod 4–5 endopod (absent in A. clarkei ).

Variation in the A. eberhardi is slight. The posterior tergal margin of pleonite 6 always has a series of small denticles, and 1–3 small denticles usually on pleuron 5, often also on pleuron 4 ( Fig. 12 ). The outer margin of the uropodal exopod has 1–3 movable spines, and the uropodal protopod bears 1–3 small dorsal spines. The outer antennular flagellum ranges in length from 0.6–1.1 times body length, generally being proportionally longer in smaller specimens. The arrangement of telson spines is highly consistent in the present series with four pairs of well-spaced marginal spines present from the smallest through largest specimen examined (10–46 mm). Only six specimens differ from the typical pattern of spination. Two specimens (paratype female, 30 mm, TMAG G6492 ; female, 43 mm, TMAG G6467 ) have, in addition to the four pairs of marginal spines, a short median spine above the posterior margin, the smaller of which also has an additional marginal median spine ( Fig. 12E,F ). The telsons of the other four specimens have asymmetrical arrangements, with unequal numbers of spines on either side of the midline (3/4, 3/4, 3/5) ( Fig. 12C,D ), or distinctly irregularly arranged spines ( Fig. 12H ). Although normally remarkably consistent in arrangement, the length of the telson spines varies allometrically, becoming proportionally shorter with increasing body size .

Anaspides listed from the Junee-Florentine system by Eberhard et al. (1991) as “telson ‘cave’ type ” are referrable to A. eberhardi . Several specimens appear to have clusters of fungal hyphae on various parts of the body including the cephalothorax, pleon, uropods and bases of the pereopods.

Given the secondary sexual features of adult males, particularly the single antennular clasping spine and similar pleopod 1, a close relationship between A. eberhardi and A. richardsoni is likely. The caves occupied by A. eberhardi are at the southern end of the wide geographic range of A. richardsoni . Anaspides richardsoni occurs throughout the caves in the Mole Creek area, but in caves around Mt Field, it has been recorded only from Rift and Growling Swallet caves, the latter of which is also occupied by A. eberhardi .

Distribution. Presently known only from caves in the Junee-Florentine Karst area: base of the Tiger Range to Cauldron Pot Cave, Niggly Cave and Welcome Stranger; 340–720 m asl.

Figures

Figure 9. Anaspides eberhardi sp. nov., male holotype, 32 mm, Niggly Cave, QVM 10:49169. Habitus, right lateral view. Scale 2.0 mm.

Figure 10.Anaspides eberhardi sp.nov., male holotype,32 mm, Niggly Cave, QVM 10:49169.(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. Scale: A–E = 2.0 mm; F–K = 1.3 mm.

Figure 11. Anaspides eberhardi sp. nov. (A–O) male holotype, 32 mm, Niggly Cave, QVM 10:49169; (P–Q) paratype female, 32 mm, QVM:2016:10:0002;(A) right thoracopod1 (maxilliped);(B–G) right thoracopods2–7;(H) left thoracopod 8;(I–J) right pleopod 1 endopod, lateral and ventral views; (K) right pleopod 2 endopod, lateral view; (L) right pleopod 5, anterior view; (M–O) pleonites 3–5 median sternal processes;(P–Q) female gonopore, right lateral and ventral views. Scale A–H, L = 2.0 mm; I–K, M–O = 1.0 mm; P–Q = 1.4 mm.

Figure 12. Anaspides eberhardi sp. nov., selected features. (A) juv. female, 10 mm, Growling Swallet, TMAG G6474; (B) juv. male, 18 mm, foot of Tiger Range, TMAG G6467;(C) female, 20 mm, unnamed cave CV43, TMAG G6478; (D) female, 31 mm, Settlement Cave, TMAG G6468; (E) paratype female, 30 mm, Cauldron Pot, TMAG G6492; (F) female, 42 mm, foot of Tiger Range, TMAG G6467; (G) female, 47 mm, Junee Cave, TMAG G6475; (H) female, 33 mm, Junee Cave, TMAG G6475; (I) male, 24 mm, Welcome Stranger, TMAG G6470;(J) paratype male, 31 mm, Cauldron Pot, QVM 10:12917; (K) paratype male, 30 mm, Niggly Cave, QVM:2016:10:0001; (L) paratype female, 32 mm, Niggly Cave, QVM:2016:10:0001. Scale A = 0.5 mm; B–D = 2.0 mm, F–G = 2.0 mm; H–L = 1.0 mm.

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