Calliax tulearensis, Ngoc-Ho, 2014

Ngoc-Ho, Nguyen, 2014, Six species of Axiidea and Gebiidea from the Indo-West Pacific (Crustacea, Decapoda), Zoosystema 36 (3), pp. 545-561 : 546-548

Genus Calliax de Saint Laurent, 1973 Calliax tulearensis n. sp.

( Fig. 1 )

MATERIAL EXAMINED. — Madagascar. Tuléar, in detritus, Galenon collected 1965/66: holotype, ♀ ( MNHN Th 1620), cl 4.5 mm, tl 20 mm.

OTHER MATERIAL EXAMINED. — Nosy Bé, Crosnier coll. 1958, ovigerous ♀, cl 7 mm, broken into three pieces ( MNHN Th 859).

DIAGNOSIS. — Rostrum broadly triangular with obtuse tip. Eyestalk approximately 1.6 times as long as wide at base, with slightly pointed tip. Telson 1.5-2 times as wide as long, lateral borders rounded, posterior border slightly convex. Antennular peduncle shorter than antennal peduncle. Pereopods 1 unequal and dissimilar; major pereopod 1 chelate, ischium and merus with eight and five lower spinules, minor pereopod 1 subchelate, ischium with seven lower spinules, pereopod 3 with small proximal heel on propodus. Uropod exopod twice as long as telson, no notch on lateral border.

ETYMOLOGY. — The new taxon is named after its type locality.

DESCRIPTION

Carapace ( Fig. 1 A-C) lacking dorsal oval, slightly shorter than pleomeres 1 and 2 combined; broadly triangular short rostrum with blunt tip in frontal margin. Cervical groove and linea thalassinica distinct, sutures absent. Eyestalks dorsally flattened, about 1.5 times as long as wide at base in holotype ( Fig. 1C ), slightly wider at base in specimen MNHN Th 859 ( Fig. 1B ), corneas retracted and non pigmented in holotype, round and subterminal in specimen MNHN Th 859 .

Telson about 1.2 times as broad as long in holotype ( Fig. 1J ), twice as broad as long in specimen MNHN Th 589 ( Fig1K ) ; lateral borders rounded, posterior border slightly convex.

Antennular peduncle ( Fig. 1C ) shorter than that of antenna, reaching approximately base of last article of the latter (last article of antennal peduncle broken in specimen MNHN Th 859).

Maxilliped 3 ( Fig. 1D ) exopod absent. Endopod with approximately quadrate ischium, merus about 0.8 time as long as broad, carpus with convex lower border, propodus as long as broad, lower border strongly flexed, dactylus with broad rounded terminal border bearing close-set serrated setae.

Pereopods 1 unequal and dissimilar. Major P1 ( Fig. 1E ) (missing in specimen MNHN Th 859), chelate; ischium and merus with eight and five spinules respectively on lower border; carpus and propodus unarmed; fixed finger as long as dactylus, with obtuse tip and small tooth at midlength of cutting edge; dactylus with curved tip.

Minor P 1 on the right in holotype ( Fig. 1F ), on the left in specimen MNHN Th 589 ( Fig. 1G ) ; ischium with seven or eight spinules on lower border; merus with convex lower border bearing two denticles in holotype, three larger spinules in specimen MNHN Th 859 ; carpus, propodus and dactylus unarmed, fixed finger with pointed tip, about half as long as dactylus and separated from it by a wide gap bearing an obtuse tooth at base, larger in specimen MNHN Th 589 ( Fig. 1G ) ; dactylus with pointed tip.

Pereopod 3 ( Fig. 1H ), pereopod 4, pereopod 5 all unarmed, small proximal heel on pereopod 3 propodus, pereopod 5 subchelate.

Female pleopod 1 ( Fig. 1M, O ) uniramous, biarticulated; female pleopod 2 ( Fig. 1L, N ) biramous, both pleopods lacking appendix interna.

Pleopods 3-5 ( Fig. 1I ) biramous, foliaceous with finger-like appendix interna.

Uropods ( Fig. 1J, K ) longer than telson, exopod nearly three times as long as telson in the young holotype, two and a half times as long as telson in the larger ovigerous MNHN Th 859 ; distal dorsal plate present, no notch on lateral border.

REMARKS

Manning & Felder (1991) separated the genus Calliax from their newly established Eucalliax on the basis of pereopods 1 unequal and dissimilar in the former, equal and similar in the latter. Yet Sakai (1999: 109; 2005: 196) synonymised the two taxa on the basis of both having maxilliped 3 without exopod and separated it from Paraglypturus Türkay & Sakai, 1995 possessing a maxillipedal exopod. Eucalliax is recognised by most later authors.

Ngoc-Ho (2003) gave characters defining Calliax and Eucalliax and recognised only two species for Calliax : C. lobata (de Gaillande & Lagardère, 1966) , type species, from the vicinity of Toulon, France and C. doerjesti Sakai, 1999 from Georgia, USA. Sakai (2011a) recognised the genus, including the same two species and added three new eucalliacine genera.

The present new species from Madagascar is the third species of Calliax . It agrees with the others (see Ngoc-Ho 2003: 489) in: 1) rostrum short, with blunt tip, rostral spine absent; 2) antennular peduncle shorter than that of antenna; 3) pereopods 1 unequal, dissimilar, minor with fixed finger shorter than dactylus and separated from it by a wide gap with a proximal tooth on the cuting edge; 4) pereopod 3 with small proximal heel on propodus; and 5) female pleopod 1 uniramous, female pleopod 2 biramous, all lacking appendix interna; pleopods 3-5 foliaceous, with finger-like appendix interna.

The new taxon resembles C. doerjesti by having no lateral notch on the uropod exopod (notch present in C. lobata ). It differs from C. lobata and C. doerjesti by:1) the shape of telson which is 1.2- 2 times as broad as long, vs about as long as broad in C. lobata ; “two-thirds length of its breadth”( Sakai 1999: 112) in C. doerjesti ; and 2) uropods longer than telson, exopod 2.5-3 times longer than telson, slightly longer than telson in C. lobata and C. doerjesti .

Both specimens studied are from Madagascar on the Mozambique side and they are likely to be of the same species. MNHN Th 859 agrees with the holotype in many characters e.g., the rostrum, the antennular peduncle shorter than that of the antenna, the maxilliped 3, the minor pereopod 1, the pereopod 3, the pleopods etc. that are figured. It differs from the holotype mainly in the shape of the telson (twice as broad as long vs 1.2 times as broad as long in the holotype). It is also damaged and broken into three pieces, therefore is not regarded as a paratype in this work.

Figures

FIG. 1. — Calliax tulearensis n. sp.: A, C, E, F, I, J, L, M, holotype,♀, tl 20 mm (MNHN Th 1620);B, D, G, H, K, N, O, non type, ♀, broken cl 7 mm (MNHN Th 859).A, lateral view;B, C, carapace; D, maxilliped 3; E, major pereopod 1; F, G, minor pereopod 1; H, pereopod 2; I, pleopod 3; J, K, telson and uropod; L, N, pleopod 2; M, O, pleopod 1. Scale bars: 1 mm.