Amazoniscus spica Campos-Filho, Aguiar & Taiti, 2020

Campos-Filho, Ivanklin Soares, Fernandes, Camile Sorbo, Cardoso, Giovanna Monticelli, Bichuette, Maria Elina, Aguiar, José Otávio & Taiti, Stefano, 2020, New species and new records of terrestrial isopods (Crustacea, Isopoda, Oniscidea) of the families Philosciidae and Scleropactidae from Brazilian caves, European Journal of Taxonomy 606, pp. 1-38 : 23-27

publication ID	https://doi.org/ 10.5852/ejt.2020.606
publication LSID	lsid:zoobank.org:pub:95D497A6-2022-406A-989A-2DA7F04223B0
DOI	https://doi.org/10.5281/zenodo.3681757
persistent identifier	https://treatment.plazi.org/id/612587B8-C976-D64D-FE5B-FA8FFCBA62D1
treatment provided by	Carolina
scientific name	Amazoniscus spica Campos-Filho, Aguiar & Taiti
status	sp. nov.

Treatment

Amazoniscus spica Campos-Filho, Aguiar & Taiti View in CoL sp. nov.

urn:lsid:zoobank.org:act:C67F79F2-111D-49D7-A9E2-FA112D32DB4B

Figs 11–14 View Fig View Fig View Fig View Fig

Diagnosis

Body pigments and eyes absent, frontal shield bent backwards over vertex, dactylus of pereopods with ungual seta simple and surpassing outer claw, male pleopod 1 exopod heart-shaped and male pleopod 1 endopod with distal portion bent outwards, bearing small setae on median margin.

Etymology

The nameof this new speciesrefers to the binary star of Spica, the brightest star in the Virgo constellation. In the Brazilian flag, this star represents the state of Pará.

Material examined

Holotype BRAZIL – Pará State,Parauapebas, Canaãdos Carajás • ♂; Jaguar, CAV-20; 6°24′22″ S, 50°22′09″ W; 20–29 May 2012; Mescolotti leg.; MZUSP 40046. GoogleMaps

Paratypes BRAZIL • 1 ♂, 2 ♀♀; same collection data as for holotype; parts of ♂ and 1 ♀ in micropreparations; MZUSP 40047 GoogleMaps • 1 ♀; CAV-17; 6°24′24″ S, 50°22′10″ W; 8–15 Mar. 2012; Oliveira leg.; MZUSP 40048. GoogleMaps

Description

MEASUREMENTS. Maximum body length: male and female 5.5 mm.

BODY. Body pigment absent. Endoantennal conglobation. Body ( Fig. 11A View Fig ) strongly convex; dorsal surface smooth, bearing small triangular scale-setae ( Fig. 11B View Fig ). Noduli laterales ( Fig. 11C View Fig ) very short, inserted near posterior margins and at same distance from lateral margins.

CEPHALON. Frontal shield bent backwards over vertex, lateral sides slightly protruding in frontal view, frontal margin broadly rounded; eyes absent ( Fig. 11A View Fig , D–E).

PEREON. Pereonite 1 without schisma or ventral lobes; pereonites 1–4 with posterior margin straight, 5–7 gradually more concave; pereonite 1 epimera with anterior corners directed frontwards, those of 2–4 with outer margin rounded, and those of 5–7 subquadrangular ( Fig. 11A View Fig ).

PLEON. Outline continuous with pereon, epimera 3–5 well developed, directed backwards with acute apices; telson triangular, slightly broader than long, with slightly concave sides, rounded apex. ( Fig. 11F View Fig ).

ANTENNULA. Composed of three articles, distal article longest, conical bearing about 10 lateral aesthetascs arranged in five sets ( Fig. 11G View Fig ).

ANTENNA. Short and stout, not surpassing pereonite 1 when extended backwards; flagellum consisting of two subequal articles, distal article bearing two lateral aesthetascs; apical organ as long as distal article of flagellum ( Fig. 11H View Fig ).

MOUTH. Mandibles with dense cushion of setae on incisor process, molar process with 10 branches, left mandible ( Fig. 12A View Fig ) with 2+1 penicils, right mandible ( Fig. 12B View Fig ) with 1+1 penicils. Maxillula ( Fig. 12C View Fig ) inner endite with two apical penicils, distal margin bearing outer tip; outer endite with 4+5 teeth, inner set with four teeth, apically cleft. Maxilla ( Fig. 12D View Fig ) inner lobe rounded and covered with thick setae; outer lobe rounded, twice as wide as inner lobe, covered with thin setae. Maxilliped ( Fig. 12E View Fig ) basis with fringe of thin setae on distal outer margin; palp with one strong seta on proximal article; endite subrectangular, medial seta surpassing distal margin, distal margin covered with thin setae and bearing one seta on outer portion, rostral surface with setose sulcus ending with one short penicil.

PEREOPODS. Pereopod 1 carpus with short, transverse antennal grooming brush; dactylus with two claws, dactylar seta simple, not surpassing outer claw, ungual seta simple, surpassing outer claw.

UROPOD. Protopod flattened and enlarged, filling gap between pleonite 5 and telson; exopod inserted on median margin, endopod twice as long as exopod and inserted proximally ( Fig. 12F View Fig ).

PLEOPOD EXOPODS. Pleopods 1 and 2 with respiratory areas.

Male

PEREOPOD 1. Merus and carpus with sternal margin covered with short scales and sparse strong setae ( Fig. 13A View Fig ).

PEREOPOD 7. Ischium elongated, sternal margin straight; carpus twice as long as merus ( Fig. 13B View Fig ).

GENITAL PAPILLA. Bearing triangular ventral shield, papilla slightly longer than ventral shield bearing two subapical orifices ( Fig. 13C View Fig ).

PLEOPODS. Pleopod 1 ( Fig. 13D View Fig ) exopod heart-shaped; endopod twice as long as exopod, distal portion bent outwards and bearing small setae on median margin. Pleopod 2 ( Fig. 13E View Fig ) exopod triangular, outer margin concave; endopod flagelliform, longer than exopod. Exopods of pleopods 3 and 4 as in Fig. 13F and G View Fig , respectively. Pleopod 5 exopod ( Fig. 13H View Fig ) triangular, outer margin sinuous, distal portion elongated, inner margin grooved to accommodate pleopod 2 endopod.

Remarks

Thegenus Amazoniscus comprises five speciesfrom Brazil: A. arlei Lemos de Castro, 1967 fromthestates of Amapá, Pará, Rio de Janeiroand Tocantins; A.eleonorae Souza et al., 2006 , A. leistikowi Campos-Filho, Araujo & Taiti, 2014 and A. zimmeri Campos-Filho, Montesanto &Araujo, 2017 fromthestateof Pará; and A. schmidti Campos-Filho, Montesanto &Araujo, 2017 fromthestateof Minas Gerais ( Souza et al. 2006; Campos-Filho et al. 2014, 2017a, 2018a). The genus is defined by having exoantennal or endoantennal conglobation, the cephalon with a frontal shield delimited superiorly by the frontal line and having a suprantennal line, pereonite 1 epimera without schisma, the antennal flagellum with two articles, the uropod protopod surpassing the telson and the male pleopod 1 exopod heart-shaped ( Schmidt 2007; Campos-Filho et al. 2014).

In lacking eyes and body pigment, and in having endoantennal conglobation, Amazoniscus spica sp. nov. is similar to A. eleonorae and A. leistikowi ; it differs from both in the shape of the exopod of the male pleopods 1 and 5 (for comparisons, see Souza et al. 2006: figs 1–19 and Campos-Filho et al. 2014: figs 23–25). This species is considered here as troglobiotic.