Neoleptastacus abbreviatus, Sak & Karaytuğ & Huys, 2024

Sak, Serdar, Karaytuğ, Süphan & Huys, Rony, 2024, Review of Neoleptastacus Nicholls, 1945 (Harpacticoida, Arenopontiidae), including an updated key to species and proposal of Phreatipontia gen. nov., Zootaxa 5525 (1), pp. 1-66 : 30-31

Neoleptastacus abbreviatus sp. nov.

https://zoobank.org/ 0BABE6B9-3B09-4AA0-838D-2880AAB1DE6D

Arenopontia? gussoae Cottarelli, 1973a sensu Mielke (1982b) [partim: material from Isla Melones, Panamá]

Original description. Mielke (1982b —as Arenopontia? gussoae ): 202–203; Figs 4A–H , 5 , 6A, C , 7A–C ).

Type locality. Panamá, Pacific seaboard; Panamá Province, Isla Melones (situated between the mainland and Taboga Island ), sandy beach; fine-medium sand with little detritus .

Body length. 360–400 μm (♀), 350–360 μm (♂) [ Mielke 1982b].

Etymology. The specific epithet (derived from the Latin abbreviatus , past participle of abbreviare, meaning to shorten, make brief) refers to the short P1 endopod which is shorter than in any other member of the gussoae - subgroup.

Remarks. Mielke (1982b) considered it plausible that his specimens of “ Arenopontia? gussoae ” from Isla Melones represented a distinct species but refrained from formally proposing it. The Panamanian material is characterized by a P1 endopod that is clearly shorter than its corresponding exopod (length ratio 0.85). Within the gussoae -subgroup only N. chilensis sp. nov. and N. emendatus sp. nov. have a comparatively short endopod, being as long as the exopod, while in all other members it is distinctly longer than the exopod ( Table 4). Additional character states that differentiate the Isla Melones form from typical N. gussoae include (1) the pointed rostrum, (2) the length ratio between P1 enp-1 and enp-2 (1.45 vs 1.25), (3) the longer female P5 (length/maximum width ratio 2.6 vs 2.0) and (4) the spiniform elements on the female P5 being unequal in length (inner one distinctly shorter than outer one) vs equally long. Mielke (1982b: Fig. 5A ) illustrated a fine outer seta on the basis of P1 but this must be an observational error.

The female specimen illustrated by Mielke (1982b: Figs 4A–C, E–H , 5 , 6A , 7A–C ) and deposited in the Zoologisches Institut und Museum der Universität Göttingen is here designated as the holotype of N. abbreviatus sp. nov. in accordance with ICZN Arts 16.4, 72.5.6 and 73.1.4. The species can be differentiated by the characters listed above ( ICZN Art. 13.1) .

Figures

FIGURE 4. Neoleptastacus acanthus (Chappuis, 1954) (♀): (A) P1, anterior; (B) P2, anterior; (C) P3, anterior; (D) P4, anterior.

FIGURE 5. Neoleptastacus acanthus (Chappuis, 1954): (A) urosome (♀), ventral [caudal ramus seta V figured at full length in inset]; (B) urosome (♂), ventral.

FIGURE 6. Neoleptastacus emendatus sp. nov. (♀): (A) habitus, dorsal; (B) habitus, lateral; (C) anal somite and caudal rami, dorsal; (D) anal somite and right caudal ramus, lateral.

FIGURE 7. Neoleptastacus emendatus sp. nov. (♀): (A) urosome, ventral; (B) antennule, dorsal; (C) antenna, outer; (D) antennary endopod, medial; (E) rostrum, dorsal; (F) midventral hook-like processes [indicated by arrows] on pedigerous somites; (G) hook-like process, lateral. [lateral endopodal spines indicated by arrows in C–D]