Instituto de Cincias Biolgicas / ICB-5, Universidade Federal de Gois, Avenida Esperana s/n, 74690-900, Goinia, GO, Brazil. .
Zootaxa. 2022 Mar 3;5105(2):269-280. doi: 10.11646/zootaxa.5105.2.6.
A new alpheid shrimp genus, Crosnierocaris gen. nov., is established for Crosnierocaris athanasoides sp. nov., a very peculiar shrimp possibly associated with decomposing sea grass accumulations in deeper water. The type series of C. athanasoides sp. nov. was collected in the Mozambique Channel, north of Grande Glorieuse Island, at a depth of 240255 m. The new genus presents a unique combination of morphological features, including the very long, slender rostrum armed with a subdistal ventral tooth; the pterygostomial angle projecting as a strong sharp tooth; the third to fifth pleura with their distoventral margins armed with two to four small teeth, a unique feature within the Alpheidae; the sixth pleuron with an articulated plate; the eyes largely exposed dorsally and laterally; the first pereiopods (chelipeds) feebly enlarged in both sexes, stouter but shorter than walking legs; the first pereiopod carpus with rows of short serrulate setae on its mesial surface; the second pereiopod carpus with five subdivisions; the third to fifth pereiopods with meri armed with stout cuspidate setae; the uropodal diaeresis with a strongly dentate lateral portion; and the complete gill-exopod formula, with mastigobranchs on coxae of the third maxilliped and first to fourth pereiopods. Within alpheid shrimps, the rostrum of C. athanasoides sp. nov. is one of the longest relative to the total body length, often reaching half of the carapace length. The phylogenetic position of Crosnierocaris gen. nov. within the Alpheidae remains to be determined, but based on its morphological characters, the new genus appears to be closest to Athanas Leach, 1814, especially in the configuration of the frontal area of the carapace, and Potamalpheops Powell, 1979, for instance, in the armature of the uropodal diaeresis and walking legs, as well as the presence of setal rows on the cheliped carpus. The new genus also shares several morphological features with Yagerocaris Kensley, 1988, which represents one of the least derived lineages within the family Alpheidae.
建立了一个新的长腹虾属，Crosnierocaris 属，以 Crosnierocaris athanasoides sp. nov. 为模式种，这是一种非常特殊的虾，可能与深海中腐烂的海草堆积有关。C. athanasoides sp. nov. 的模式系列是在莫桑比克海峡大格罗里厄斯岛以北，水深 240-255 米处采集的。新属具有独特的形态特征组合，包括非常长而细的额角，其腹侧近末端具一齿；胸角突出呈强锐齿；第三至第五胸节的腹侧缘具 2-4 个小齿，这是 Alpheidae 内的一个独特特征；第六胸节具关节板；眼睛大部分暴露在背部和侧面；第一对步足（螯肢）在两性中均微弱增大，较步行足粗壮但短；第一对步足腕节的内表面具排短锯齿状刚毛；第二对步足腕节具五部分；第三至第五对步足的长节具粗壮的尖刺状刚毛；尾节的间腹板具强烈锯齿状的侧部；完整的鳃外肢公式，第三颚足和第一至第四对步足的基节具触角原肢。在长腹虾属中，C. athanasoides sp. nov. 的额角相对于体全长而言是最长的之一，通常达到头胸甲长度的一半。Crosnierocaris 属在 Alpheidae 中的系统发育位置仍有待确定，但基于其形态特征，新属似乎与 Athanas Leach, 1814 最为接近，尤其是在头胸甲额区的形态，以及 Potamalpheops Powell, 1979，例如，在尾节间腹板和步行足的装备，以及螯肢腕节的刚毛列。新属还与 Yagerocaris Kensley, 1988 具有几个形态特征，后者是 Alpheidae 科中最不衍生的谱系之一。
