Ischnomera sicula, Bologna & Poloni & Vázquez, 2019

Bologna, Marco A., Poloni, Riccardo & Vázquez, Xavier A., 2019, A new Ischnomera of the I. xanthoderes (Mulsant, 1858) complex (Coleoptera Oedemeridae) from Sicily, Zootaxa 4671 (4), pp. 541-550 : 542-545

Ischnomera sicula n.sp.

( Figs. 1a, c , 2a, b , 3a , 4 , 5 , 6 )

Type specimens. Holotype male 1, and 1 female paratype, Sicilia, Ficuzza, 19/ 27.V.1906, A. Dodero, I. xanthoderes det. (=identified) M. Magistretti ( MSNG); 1 male paratype, Sicilia, Bosco Ficuzza ( PA = Palermo province), 700 m, 6.VI.1991, F. Angelini, Ischnomera n.sp. det. M. A. Bologna ( MAB); 1 female paratype, Italia, Sicilia, Palermo, Bosco della Ficuzza, Torretta Torre, 940 m, area Con.Eco.For, SIC 1, Malaise trap, XII.2004, A. Gatto, I. xanthoderes M.A. Bologna & F. Montalto det. ( MAB; the date of this record is unusual for this species and possibly refers to November, being the Malaise traps checked once for month during the Con.Eco.For project); 1 female paratype, Sicilia ( PA), Madonie, Ficuzza, m 830, 37°52.57N - 013°22.93E 4.V.2007, A. Liberto, su Crataegus in fiore (on blossoming Crataegus ) ( CL); 1 male paratype, Sicilia, Castelbuono, fine (= end) V.1906, A. Dodero, I. xanthoderes det. M. Magistretti ( MSNG); 1 female paratype, Sicilia ( PA), Madonie, Vallone Zottafonda, m 1700, 22.VI.2012, M. Romano ( CL); 1 male paratype, Sicilia, PA, Madonie, P. (= Piano) Battaglietta, 1600 m, 20.VI.1998, M. Romano ( CP) (from the same locality was examined also the photo in Fig. 6 ); 1 male paratype, Sicilia, Madonie, PA, Piano Battaglietta, m 1600, 20.VI.1998, M. Romano leg. ( CR); 1 paratype, Sicilia, M.ti Madonie Piano Zucchi e dint. 950-1150m, 7.VI.1991, F. Angelini, I. xanthoderes F. Angelini det. ( MSNV); 1 female paratype, Sicilia, M. Nebrodi ( ME) (= Messina province ), str. (=road) S. Fratello-P.lla (= Portella) Femmina morta, 11.VI.1991, 900- 1100 m, F. Angelini, I. xanthoderes det. M.A. Bologna 1993 ( MZUF); 1 female paratype, Sicilia, M. Nebrodi, P.lla Femmina morta ( ME), m 1520, 13.VI.1982, F. Angelini, I. cfr. tenietensis det. M. A. Bologna ( MAB).

The holotype lacks part of the left antenna; some paratypes lack parts of antennae and legs. Male genitalia of one paratype were dissected and are mounted on a card pinned with the specimen.

Description. Head dark blue metallic, antennae black piceous, antennomeres I-II (in some specimens also III) flavous-brown dorsally, and I-II flavous-brown ventrally; clypeus black, except anterior third flavous; mandibles, maxillae and labial palpi black, maxillary palpi black dorsally, but third palpomere in some specimens slightly brown, flavous-brown ventrally in most specimens. Pronotum and pro-episternum shiny orange; elytra shiny metallic green, in few specimens almost black (possibly as consequence of the preparation). Thorax metallic black ventrally, abdomen dark blue with metallic lustre. Body setation light-coloured, slightly darker on legs. Body length: 7,5–9,5 mm.

Male ( Figs. 5a, c ). Head ( Fig. 4 ) densely punctate dorsally, intermediate surface shagreened, space between two punctures smaller than the puncture diameter. Setae very short and denser on frons. Eyes bulging; maximal width of head on eyes distinctly smaller than maximal width of pronotum. Two fore oblique sligth depressions converging on frons; fronto-clypeal area distinctly and transversally depressed. Labrum almost straight on fore margin. Last maxillary palpomere distinctly securiform, maximal width in the middle ca. 0.5 as long. Antennnae slightly exceeding the middle of elytra, covered by dense and very short setae; antennomeres subcylindrical and slender, II distinctly shorter than I, which is shorter than III; III-VII similar in length, VIII-X slightly shorter than previous ones; XI about as long as X, slightly narrowed apically.

Pronotum subcordiform ( Fig. 4 ), almost glabrous, slightly longer than wide, maximal width in anterior third, distinctly narrowed posteriorly to the widest point, anteriorly slightly narrowed; one rounded central depression at base and two wide depressions relatively deep, more or less confluent and without an evident middle keel. Punctures dense, deep and distinct, not confluent, intermediate surface shiny, not shagreened. Ventral surface of claws without a distinct tooth, but with basal portion widened and stout distally. Elytra lustrous, densely punctate and more rugosely punctate on posterior third. Sutural margin raised on the anterior half, first costa not extended on poosterior third, second costa more distinctly extended posteriorly but not reaching the apex, third costa starting posteriorly to humerus and more extended posteriorly than second. Elytral setation short but densely and more or less longitudinally distributed on the whole surface. Elytra suboval in the last portion, apex rounded. Tarsal claws ( Fig. 3a ) without ventral tooth.

Posterior margin of last tergite suboval, posterior margin of last ventrite as in Fig. 5c . Male genitalia as in Figs. 1a, c , 2a, b .

Female ( Fig. 5b ). Differs from male by the following characters: antennae slghtly shorter, reaching the middle of elytra; last maxillary palpomere less securifrom, in the middle ca. 0.3 as wide as long; pronotum as wide as long; last ventrite widely incised.

Ethymology. The name of the species refers to its distribution, limited to the mountains of northern Sicily. Taxonomic remarks. As noted in the introduction, the Sicilian populations of this complex were previously recorded as I. xanthoderes by several authors, but already Bologna (1995) supposed a subspecific distinction and Vázquez (2002) that they could be referred to I. tenietensis .

The new Sicilian species differs from I. tenietensis at least in the following morphological characters: male antennomeres distinctly slender, especially VIII-X, which in the Maghrebian species are shorter and sligthly widened apically; antennomeres I-II ventrally flavous-brown instead of black; maxillary palpomeres I-II dorsally brown instead of dark black and I-III ventrally usually flavous-brown instead of black; pronotal punctures wider and not distinctly approached and surface shiny instead subopaque; elytral surface shiny instead of subopaque and elytral apex of male more rounded; aedeagus slender and longer, parameres more divergent and less pubescent. From I. xanthoderes differs at least by the colour of basal antennomeres which are piceous in this species, the ventral side of claws which are distinctly toothed in I. xanthoderes , the aedeagus, which is more curved in I. xanthoderes . Differences among these three West Mediterranean species are synthetically included below in a key.

Distributional and Ecological notes. The new species is endemic to northern Sicily ( Fig. 8 ): records of presence spread from 700 to 1600 m a.s.l. in the Sicilian Apennines (Sicani, Madonie and Nebrodi ranges. Only two detailed Sicilian localities, Ficuzza and Castelbuono (Palermo province), personally confirmed, were recorded in the literature ( Ragusa, 1897; Luigioni, 1929; Magistretti, 1942, 1967).

Phenological records refer to May and June, except one in November, collected by Malaise trap. According with the scarce information from collectors (F. Angelini, A. Liberto), some specimens were collected on Crataegus flowers in pastures of temperate forests of Quercus cerris Linnaeus, 1753 and Fagus sylvatica Linnaeus, 1753 . One specimen (Madonie Mts., Piano Battaglietta, 25.V.2013) was photographed on a yellow Apiaceae by C. Muscarella (Palermo) (http://www.entomologiitaliani.net/public/forum/phpBB3/viewtopic.php?f=180&t=44849&hilit=xantho deres).

Ischnomera tenietensis , distributed in the Maghrebian mountains, is ecologically relatively close to I. sicula and seems associated to Mediterranean mountain forest habitats. According to information from collectors (E. Colonnelli and G. Magnani) in Algeria (Akfadou) it was collected in forest of Q. afares Pomel, 1874 and Q. canariensis Willdenow, 1809 , while Bedel (1885) cited this species (as I. xanthoderes ) from forests of Cedrus atlantica (Endl.) ex Carrière, 1855 (Theniet El Had) on Apiaceae yellow flowers and hypothesized that it develops inside the cedar wood.

Ischnomera xanthoderes is a thermophilic element occurring on most of the Iberian Peninsula (excepting Pyrenees and Cantabric mountanis), and Mediterranean part of Southern France (Vázquez et al., 2017), especially in Quercus forests ( Vázquez et al., 2002a; Perez & Vázquez, 2016). Adults were collected in Spain, between March and November ( Vázquez, 1989), on Cistus spp. ( Cistaceae ) and Thapsia sp. ( Apiaceae ) (Vázquez, 2002), as well as on Quercus by aerial traps ( Vázquez, 2002b). In southern France it was collected in April on Genista scorpius (L.) D.C. ( Fabaceae ) and in May on yellow Asteraceae and Quercus flowers ( Pic, 1898; Mayet, 1903; Caillol, 1919). According to Caillol (1919), the larva develops in old dead trunk of Quercus petraea (Mattuschka) Liebl., 1784 (as Q. sessiflora Salisb. ), and Mayet (1903) hypothesized that adults eclose in Autumn and undergo a winter diapause under bark.

Figures

FIG. 1. Male genitalia: aedeagus of Ischnomera sicula n. sp. (a) and I. tenietensis (b); tegmen of I. sicula n.sp. (c) and I. tenietensis (d).

FIG. 2. Male genitalia and claws: Ischnomera sicula n.sp., aedeagus (a), apical portion of tegmen (b); I. tenietensis, aedeagus (c), apical portion of tegmen (d); I. xanthoderes, aedeagus (e), apical portion of tegmen (f); I. tenietensis, tarsal claws (h); I. xanthoderes, tarsal claws (g). Figures of both I. xanthoderes and I. tenietensis modified from Svihla (1988).

FIG. 3. Tarsal claws: Ischnomera sicula n.sp. (a); I. tenietensis (b); I. xanthoderes (c).

FIG. 4. Ischnomera sicula n.sp., head and pronotum.

FIG. 5. Ischnomera sicula n.sp., male paratype in dorsal view (a), female paratype in dorsal view (b), male paratype in ventral view (c).

FIG. 6. Ischnomera sicula n.sp. in the field (Sicily, Palermo prov., Madonie, Piano Battaglietta, photo C. Muscarella).

FIG. 8. Distribution of the species of the Ischnomera xanthoderes complex: I. xanthoderes, light blue spot; I. tenietensis, green; I. sicula n. sp., red.