A note on an Ancylomenes (Crustacea: Decapoda: Pontoniinae) from the Siboga expedition Author Bruce, A. J. text Zootaxa 2011 2011-08-23 3001 1 65 67 https://biotaxa.org/Zootaxa/article/view/zootaxa.3001.1.5 journal article 10.11646/zootaxa.3001.1.5 1b2a3450-a761-422e-a6b0-d0c62c1afc2a 1175-5326 5280862 Ancylomenes lipkei sp. nov. ( Fig. 1 ) Periclimenes (Periclimenes) aesopius — Holthuis, 1952 , Siboga Exped. Mon , 39a10: 35-37 ( partim ), fig. 6d. Material examined. . 1 ov. ♀ , holotype , Indonesia , Siboga stn. 33, Bay of Pidjot , Lombok , 22 m (or less), 24-26 March 1899 , ZMA De. 206074 . Diagnosis. Small sized slender shrimp of the genus Ancylomenes Okuno &Bruce. Rostrum ( Fig. 1B ) about 0.77 of CL, strongly arched, moderately elevated, ventrally concave, reaching to middle of intermediate segment of antennular peduncle, with 10 small acute teeth dorsally, first tooth situated on carapace, ventral margin concave, setose, with minute acute subterminal tooth; carapace ( Fig. 1A ) with inferior orbital angle strongly produced, acute, with reflected inner flange; antennal spine slender, marginal, well below inferior orbital angle, slightly above level of slender hepatic spine, slightly anterior to the level of first dorsal rostral; basicerite with acute dorsal protuberance proximally; third abdominal tergite ( Fig. 1D ) slightly posteriorly produced, not carinate; ophthalmic somite ( Fig. 1B ) with small rounded ophthalmic process; first pereiopod normal, second pereiopod ( Fig. 1E ) chela not bowed ( Fig. 1F ), 0.8 of CL, with fingers ( Fig. 1G ) about 0.65 of palm length, dactylus with 3 teeth mainly on proximal half, subacute, moderately recurved, tip of dactylus swollen, feebly notched, semi-dentate ( Fig. 1H ), fixed finger with 4 small blunt recurved teeth acute teeth proximally, on both fingers the distal tooth well separated from the proximal teeth by feeble diastema; carpus 0.8 of chela length, 0.9 of meral length: ischium subequal to merus length; third ambulatory pereiopod with dactyl biunguiculate, slender ( Fig. 1J ), 7.0 times longer than basal width, 0.3 of propod length, with small slender accessory tooth at 0.7 of length, not closely adpressed, unguis not clearly demarcated: propod ( Fig. 1J ) about 15.7 times longer than width, with single long distoventral spine, one long ventral spine at 0.75 of propod length, distoventral spine shorter than ventral spine. Systematic position. Closely resembling A adularans ( Bruce, 2003 ) . Differs from that species in the following features: Rostral dentition 10/1 ( vs 11–13/1), dorsal carina less deep, dorsal margin less strongly convex, first rostral tooth only on carapace, ventral margin with minute distal tooth, inferior orbital angle less acute, without upturned tip, ventral flange feebly developed, antennal spine further removed below inferior orbital angle, almost on same level as hepatic spine ( vs at much higher level), second pereiopod with fingers of chela greater than half palm length ( vs shorter than palm), fingers with 3–4 small recurved teeth ( vs dactyl unarmed, fixed finger with 2 small teeth), palm longer than merus ( vs shorter), carpus shorter than palm ( vs longer), subequal to merus and ischium, ambulatory pereiopod dactylus with accessory tooth less adpressed to unguis ( vs strongly adpressed), propod with single long distoventral spine ( vs paired distoventral teeth), single extra long ventral spine only ( vs with short additional ventral spine). FIGURE 1. Ancylomenes lipkei sp. nov. , holotype, ZMA De. 206074. A, carapace and rostrum. B, anterior carapace and rostrum. C, inferior orbital angle. D, third abdominal segment. E, second pereiopod. F, same, chela. G, same, fingers. H, same, tip of dactylus. I, third pereiopod, propod and dactyl. J, same, distal propod and dactyl. Measurements. CL 3.2 mm . Total length 25mm ( Holthuis, 1952 ). Etymology. The species is named in honour of the late Dr Lipke B. Holthuis, in recognition of his outstanding contribution to the systematics of the Pontoniinae and with thanks for the seminal donation to the author of his last author’s copy of the pontoniine volume of the Siboga Expedition monographs many years ago. The present species is also closely related to Ancylomenes holthuisi (Bruce, 1969) . Remarks . The single specimen of Ancylomenes lipke i is in a poor state with the thoracic region and abdomen almost completely separated, the abdomen is broken at segments 5/6. One first and second pereiopod is still attached, with one second pereiopod detached; the third ambulatory pereiopod now detached. Also, one loose mandible and two detached pleopods, and the left eye are present in the vial. Holthuis’s fig.6d shows a slender distal spine on the propod of the ambulatory pereiopod with a similar ventral spine close by. It is probable that this spine has been lost in Fig. 1J , unless other pereiopods were originally preserved. Of the other specimens, which are not readily identifiable with described species and may be the subject of a future report, the one from Banda, 9-36 m , 1899, ♀ , CL 4.6mm , with a rostral dentition of 1+7/2, is highly macerated but may be A. speciosus (Okuno, 2004) . This specimen is badly macerated with the third abdominal segment damaged, with both first pereiopods, the left second pereiopod only, still attached, three detached ambulatory propods with dactyls, right fifth still attached, others missing. The telson is damaged proximally, the small anterior and posterior dorsal spines and posterior marginal spines are separated by equal distances. The specimen from Siboga stn 164, 32m, ovig. ♀ , CL 4.5mm , rostral dentition 1+7/1, is also rather macerated, complete, but with the abdomen broken at the third and fourth segments articulation. It probably represents a new species related to A. speciosus . Holthuis (1952) notes the specimen as an ovig. ♀ but few ova are preserved, none attached. The specimens from Siboga stn 240, 2 ovig. ♀ , CLs ca 5.0mm, are not in good condition. One has the carapace completely destroyed, the remains lacking a rostrum. It is otherwise in a reasonable state with both first pereiopods attached, also the right second pereiopod, right fourth and fifth pereiopods and left third, fourth and fifth. The second specimen also has a damaged carapace, with the rostrum broken, the detached fragment preserved, the abdomen is severed at the junction of fifth and sixth segments: the distal part is preserved but the distal half of the telson is missing. One first pereiopod and three ambulatory pereiopods are still attached. One third maxilliped was also removed. One first pereiopod and one second pereiopod are detached and un-attributable. The specimens appear to resemble A. luteomaculatus Okuno and Bruce (2010) .