Alpioniscus (Illyrionethes) mandalinae, Bedek & Gottstein & Taiti, 2019

Bedek, Jana, Gottstein, Sanja & Taiti, Stefano, 2019, Taxonomy of Alpioniscus (Illyrionethes): A. magnus and three new species from the Dinaric Karst (Isopoda: Oniscidea: Trichoniscidae), Zootaxa 4657 (3), pp. 483-502 : 497

Alpioniscus (Illyrionethes) mandalinae n. sp.

( Figs 12–15 )

http://zoobank.org/ 83BC3A4A-3D1B-4CE8-9726-A80D9DD77919

Alpioniscus (Illyrionethes) sp. 5.— Bedek et al. 2019: figs 3, 5.

Material examined. Croatia, Dalmatia : Holotype male, Šibenik , Mandalina, Mandalina (cave CCC HR00247 ), 43.7111°N, 15.9021°E, 19 October 2012, leg. J. Bedek ( CBSSC IT4297 ).

Paratypes. 1 female, 1 juv., same data as holotype ( CBSSC IT2860 ) ; 1 female, same locality and date, leg. K. Miculinić ( CBSSC IT2861 ) ; 1 male juv., same locality, 13 February 1998, leg. S. Vujčić-Karlo ; 1 male, 5 females, same locality, 15 January 2002, leg. B. Jalžić ( CBSSC IT270 ) ; 2 females, same locality, 6 October 2005, leg. M. Lukić ( CBSSC IT319 ) ; 5 females, same locality and date, leg. J. Bedek ( CBSSC IT320 ) ; 2 females, same local- ity and date, leg. R. Ozimec ( CBSSC IT3027 ) ; 6 females, 1 juv., same locality and date, leg. M. Pavlek ( CBSSC IT4001 ) ; 5 males, 7 females, same locality, 8 May 2010, leg. A. Kirin ( CBSSC IT2166 ) ; 2 females, same locality and date, leg. J. Bedek ( CBSSC IT2168 ) ; 1 female, same locality and date, leg. P. Kovač-Konrad ( CBSSC IT2173 ) ; 3 females, same locality and date, leg. M. Lukić ( CBSSC IT2174 ) ; 3 males, 3 females, 2 juvs, same locality, 14 December 2014, leg. P. Kutleša ( MZUF 9844 ) ; 2 males, 6 females, 2 juvs, same locality and date, leg. J. Bedek ( CBSSC IT3998 ) ; 2 males juv., 15 females, same data ( CBSSC IT4006 ) ; 1 male, 17 females, 2 juvs, same locality, 5 March 2015, leg. J. Bedek ( CBSSC IT3996 ) ; 2 males, 18 females, same locality, 10 October 2016, leg. J. Bedek ( CBSSC IT3997 ) .

Description. Maximum length: male, 3.5 mm; female, 6.3 mm. Colourless body, pereon with almost parallel sides, pleon narrower than pereon ( Fig. 12A ). Back smooth to slightly granulated, with ridges near posterior margins of cephalon and pereonites 1–6, and some triangular scale-setae ( Fig. 12B ). Some gland pores on lateral margins of pleonites 4 and 5 ( Fig. 12C ).

Cephalon ( Fig. 12C ) with suprantennal line bent downwards; antennal lobes rounded. Eyes absent. Posterior margin of pereonites 1, 2 convex, of pereonite 3 slightly convex, and of pereonites 4–7 progressively more concave. Pleonites 3–5 with small posterior points visible in dorsal view ( Fig. 12D ). Distal part of telson with concave sides and broadly rounded apex ( Fig. 12D ).

Antennula ( Fig. 12E ) of three articles, distal article flattened with six to eight aesthetascs. Antenna ( Fig. 12F ) with peduncle granulated; flagellum of eight to 10 articles with one row of aesthetascs on four to five different articles, always on second and third. Buccal pieces as in A. magnus .

Pereopods similar in shape, ungual seta simple, dactylar seta bifid and setose ( Fig. 13A ).

Uropod ( Fig. 12D ) with protopod slightly grooved on outer margin; endopod distinctly shorter than exopod, proximally inserted.

Male: Pereopod 1 ( Fig. 13A ) carpus bearing five setae. Pereopod 1 and 2 propodus and carpus bearing numerous short scales on rostral surface; merus with sternal margin straight, pereopods 3–6 merus with progressively more concave sternal margin and small lobe proximally. Pereopod 7 ( Fig. 13B ) ischium with straight sternal margin; merus with slightly concave sternal margin and hook-shaped lobe proximally, with scales and one large seta; carpus with straight sternal and tergal margins.

Genital papilla ( Fig. 14A ) with rounded apical part.

Pleopod 1 ( Fig. 14A ) exopod triangular, wide, with rounded apex, almost straight outer margin, convex inner margin; endopod narrow with wide basal part and concave outer margin, with apical seta distinctly shorter than basal article.

Pleopod 2 ( Fig. 14B ) exopod triangular with slightly concave outer margin; endopod of two articles, distinctly longer than exopod, distal article proximally narrower with strong bifid terminal seta. Pleopod 3–5 exopods as in A. lossinii .

Etymology. The new species is named after Mandalina, name of the cave and peninsula where the specimens were collected.

Remarks. Alpioniscus mandalinae differs from all the other species lacking a tergal hump on the male pereopod 7 carpus by the wide male pleopod 1 exopod with almost straight outer margin.

Figures

FIGURE 12. Alpioniscus (Illyrionethes) mandalinae n. sp. A, paratype female CBSSC IT4001 from Mandalina. B–D, paratype male CBSSC IT2166 from Mandalina. E, F, paratype male CBSSC IT3997 from Mandalina. A, specimen in dorsal view; B, dorsal scale-seta seta; C, cephalon, dorsal; D, pleonites 4, 5, telson and uropods; E, antennula; F, antenna with enlargment of flagellum. Scale bars: A, C, D, F = 1 mm; B = 0.01 mm; E, 0.1 mm.

FIGURE 13. Alpioniscus (Illyrionethes) mandalinae n. sp. Paratype male CBSSC IT3997 from Mandalina. A, pereopod 1 with enlargment of dactylus; B, pereopod 7 rostral view with enlargements of merus and hook. Scale bar: 1 mm.

FIGURE 14. Alpioniscus (Illyrionethes) mandalinae n. sp. Paratype male CBSSC IT3997 from Mandalina. A, genital papilla and pleopod 1; B, pleopod 2 with enlargement of endopod tip. Scale bar: 0.1 mm.

FIGURE 15. Distribution map of analysed specimens of the Alpioniscus species, magnus-lineage in Croatia.