Maghreboniscus rojasi Garcia 2022, sp. nov

Autor: Garcia, Lluc
Rok vydání: 2022
Předmět:
DOI: 10.5281/zenodo.7128890
Popis: Maghreboniscus rojasi sp. nov. Figs. 1–4 http://zoobank.org/ urn:lsid:zoobank.org:act: F0FB8290-7B4E-49A4-903D-0139FB8DD57D Spelaeoniscus sp. Garcia & Rojas, 2021, p. 48: fig. 2. Material examined. Holotype: Male, SPAIN: Cádiz, Tarifa (36 01 18.4 N, 05 36 06.1 W), coastal grassland, 51 m a.s.l., 30 December 2021, leg. Daniel Rojas Pichardo (preserved in a vial with 70% ethanol; MBCN 24689). Paratypes. 3 females, same collection data as holotype, preserved each in vials with 70% ethanol (MBCN 24690, 24691 and 24692). 1 male, same collection data as holotype, dissected and mounted in 4 microscope slides (MBCN 24693-1, 24693-2, 24693-3 and 24693-4). 1 additional female, same collection site and collector as precedent, 17 February 2021 (deposited in the author’s collection). Diagnosis. The new species is characterized by the following unique combination of features: body covered with straight scale-setae and second pleopod of male with sub-triangular exopod. Description. Maximum length observed: male, 1.5 mm; female, 1.7 mm. Exoantennal conglobation. Habitus and body outline as in figure 1 A–B. Body unpigmented; head and dorsum covered with erect straight scale-setae, laciniate apically (Fig 2 A). Cephalon with well delimited antennal furrows, not deep, short, occupying about half of total head length; scutellum wide and smooth, with rounded inferior edge; eyes absent (Fig. 2 B). Pereonite 1 with entire posterolateral corners, without schisma (Fig. 2 C). Epimera of pereonites 2–4 with rounded margins, 5–7 straight. Epimera of pleonites 3–5 with straight margins. Noduli laterales situated far from lateral margin of pereon-tergites and close to its hind margin. Pleotelson dorsally convex, nearly semicircular, somewhat narrowed posteriorly (Fig. 2 D). First antenna of 2 articles; distal article with 3 short and thick aesthetascs, digitiform (Fig. 2 F). Second antenna short, when extended backwards not reach to the posterior half of pereonite 1; fifth article swollen; flagellum bi-articulated, with proximal article three times shorter than distal; distal article with two aesthetascs (Fig. 2 G). Mandibles with dichotomized molar penicil, bearing 6 setae each; right mandible with 1+1 free penicils (Fig. 3 A); left mandible with 2+1 free penicils (Fig. 3 B). Maxillula outer endite bearing 4+4 teeth and small additional tooth (Fig. 3 C); inner endite with two sub-equal penicils inserted apically (Fig. 3 D). Maxilla apically bilobed, inner lobe bigger than outer one, bearing 5–7 sensilla on outer margin and 3 on caudal face (Fig. 3 E). Maxilliped: endite with straight inner margin, upper margin smooth and thick single seta on caudal face; palp with two large setae on basal article, articles 2–3 fused, with 2 long setae on inner margin and 1 equally long seta-like structure between them, 1+2 setae inserted distally and 3 short setae on outer margin (Fig. 3 F). Male. Pereopod 1 not modified, with brush of setae and plumose setae on propodus; propodus with 1 strong laciniate seta on ventral margin; dactylus with inner claw longer than outer one (Fig. 4 A–B). Pereopod 7 not modified; propodus with 4 strong laciniate setae on ventral margin (Fig. 4 C). Pleopod 1 exopod small, sub-elliptical; endopod straight, apically pointed, with a sub apical lamella on caudal face (Fig. 4 D). Pleopod 2, exopod sub-triangular, with wide basal half and narrow distal half; endopod sinuous, longer than exopod, with wide basal part and apical third narrow and slightly curved inwards (Fig. 4 E). Uropod not modified, with endopodite much larger than exopodite, dorsoventrally flattened and with denticulated inner margin (Fig. 2 E). Derivatio nominis. The new species is dedicated to its first collector, Daniel Rojas Pichardo, naturalist and student of the Andalusian biodiversity. Remarks. M. rojasi sp. nov. is closely related to M. palmetensis, which also has a body covered with erect and straight scale-setae, and a wide cephalic scutellum. The first male pleopod is similar in both species. However, it is distinguished by the shape of the second male pleopod, which in M. rojasi has a large and sub-triangular exopod, while it is small and transversely oval in M. palmetensis. Both species also differ in the shape and size of the uropod endopodite. From M. trapezoidalis it is distinguished, among other features, by the elongated instead of flabelliform scale-setae and by the rounded instead of trapezoidal pleotelson (the male pleopods of M. trapezoidalis have never been illustrated, but Vandel (1959) indicated that there are no major differences with those of M. palmetensis). Finally, M. rojasi sp. nov. differs from M. minimus by the straight as opposed to flabelliform scale setae, and by the shape of the pleotelson and the uropods. The following key allows an easy separation of the four species hitherto included in the genus.
Published as part of Garcia, Lluc, 2022, Description of Maghreboniscus rojasi sp. nov. from Southern Spain and validation of the genus by the designation of a type species (Isopoda: Oniscidea: Spelaeoniscidae), pp. 267-274 in Zootaxa 5190 (2) on pages 268-272, DOI: 10.11646/zootaxa.5190.2.6, http://zenodo.org/record/7120333
{"references":["Garcia, L. & Rojas, D. (2021) Isopodos terrestres (Crustacea: Oniscidea) de Andalucia. Nuevas citas y especies interesantes. Revista de la Sociedad Gaditana de Historia Natural, 15, 47 - 52.","Vandel, A. (1959) Nouvelles recherches sur les isopodes volvationnels exoantennes et la genese de leur coadaptions. Bulletin biologique de la France et de la Belgiqu e, 93, 121 - 139."]}
Databáze: OpenAIRE