この研究では、熱帯東太平洋の生物多様性のホットスポットに生息する小型海綿エビ（デカポダ: Palaemonidae）に対応するために、新しいパラエモンエビ属を設立した

Unesconia coibensis, gen. et sp. nov., a miniature sponge-associated shrimp from a biodiversity hotspot in the tropical eastern Pacific (Decapoda: Palaemonidae).

• Arthur Anker

抄録

本研究では、このような生物多様性のホットスポットに生息する小型海綿類を対象に、新種のパラエモンエビ属（Unesconia gen.nov.）を確立した。パナマの太平洋岸、コイバ群島の浅い海域で発見された数種の標本に基づいて、新属と新種の説明を行う。本属は他の東太平洋や西大西洋のパラエモン属との親和性が低いように思われる。一方で、それは海綿に関連した種を含む3つのインド-西太平洋の属と多くの文字を共有しています。Unesconia gen.nov.の最も重要な診断上の特徴は，強く亀頭状になること，背びれがあることである。吻は強く甲状で背側にくぼんでおり，側方の甲状突起は基底部で大きく拡大し，強い眼窩上歯を持つ。外套脚の側方には、外套脚の側縁までは伸びないが、外套脚の側縁までは伸びない5本の棘状セタエを持つ外套脚ディアレシスの側方断面。

A new palaemonid shrimp genus, Unesconia gen. nov., is established to accommodate a peculiar, small, presumably sponge-associated species, Unesconia coibensis gen. et sp. nov. The description of the new genus and species is based on several specimens found in the shallow marine waters of the Coiba Archipelago, Pacific coast of Panama. Unesconia gen. nov. does not seem to have close affinities to other eastern Pacific or western Atlantic palaemonid genera, including those harbouring sponge symbionts. On the other hand, it shares many characters with three Indo-West Pacific genera, which contain sponge-associated species, viz. Paraclimenaeus Bruce, 1988, Apopontonia Bruce, 1976 and Climeniperaeus Bruce, 1996. The most important diagnostic features of Unesconia gen. nov. are the strongly carinate, dorsally dentate rostrum, with its lateral carinae greatly expanded basally and armed with strong supraorbital teeth; the non-filtering mouthparts, with mandible lacking palp; the first pereiopod chela with excavated fingers and strongly tridentate fingertips; the asymmetrical second pereiopods (chelipeds), with the major chela bearing a double-fossa mechanism on the finger cutting edges; the ambulatory pereiopod dactylus armed with one large tooth and at least two small spinules on the ventral margin of the corpus, in addition to the terminal unguis; the lateral section of the uropodal diaeresis armed with five spiniform setae, the latter not extending to the lateral margin of the exopod; and the telson with two pairs of stout long cuspidate setae on dorsal surface and three pairs of strong, elongate spiniform setae on the posterior margin.