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Loretoniscus Ocampo-Maceda, López-Orozco & Campos-Filho gen. nov. urn:lsid:zoobank.org:act: 293A9B09-3480-4B20-807B-64C27672ACD0 Type species Loretoniscus mashiriaensis gen. et sp. nov., by present designation and monotypy. Diagnosis Body convex. Animals with partial conglobation ability; exoantennal conglobation. Cephalon with welldeveloped antennary lobes, triangular frontal shield slightly developed, laterally interrupted by antennal grooves, frontal line delimiting frontal shield on upper portion. Pereonite 1 epimera without dorsolateral furrows and schisma. Pereonites 1–3 without ventral lobes. Pleon outline continuous with that of pereon. Telson triangular with distal portion covering uropod endopods. Antennula with three articles. Antenna with flagellum of three articles, second and third articles divided by thin suture. Mandible with molar penicil dichotomized. Maxillula outer endite with outer group bearing teeth cleft at apex. Uropod protopod subrectangular, exopod inserted distally. Pleopod exopods 1 and 2 with respiratory areas. Etymology The new genus is named after the department where the specimens were collected: Loreto. Remarks In the complex shape of the depressions in the frontal shield of the cephalon, and the absence of dorsolateral furrow on pereonite 1 epimera, Loretoniscus gen. nov. resembles Iansaoniscus; however, it differs in the broad shape of the telson with lateral margins straight (vs concave), uropod protopod subrectangular (vs subquadrangular), and pleopod 1 and 2 exopods with respiratory areas (vs absent). The Pudeoniscidae were recently revised by Campos-Filho et al. (2018b). The diagnostic characters of the family do not comprise the variation observed in Iansaoniscus and Loretoniscus gen. nov. Thus, the diagnosis of the family after Campos-Filho et al. (2018b) is emended as follows: animals with exoantennal conglobation; cephalon with triangular frontal shield and profons having complex depressions, and pereonite 1 epimera with dorsolateral furrow to fit antennae during conglobation (reduced or absent in cave-dwellers or endogean species); epimera of pereonites 1–3 with small ventral lobes or schisma on pereonite 1 (reduced or absent in cave-dwellers or endogean species); pleon outline continuous to that of pereonite 7, neopleurae 3–5 well developed and rectangular, telson triangular or trapezoidal with proximal portion wider than distal portion; antennal flagellum of three articles, second and third divided by suture; uropod protopod subquadrangular, exopod inserted distally, endopod not surpassing the distal margin of telson; and pleopod exopods with respiratory structures. Loretoniscus gen. nov. is included in the family Pudeoniscidae by sharing most of these mentioned characters. The absence of dorso-lateral furrow and schisma on pereonite 1 epimera, and absence of ventral lobes on pereonites 1–3 epimera are closely related with the conglobation ability, an ecomorphological strategy of oniscideans used against predation and to reduce water loss (Edney 1951; Schmalfuss 1984). The new genus includes one new species with endogean habits, and probably the absence of these structures is related with habitat selection. |
