Otiorhynchus (Nihus) grischunensis, Germann, Christoph, 2010

Germann, Christoph, 2010, Otiorhynchus (Nihus) grischunensis sp. n. — a new species of the O. rhilensis species group from the Swiss Alps (Curculionidae, Entiminae), Zootaxa 2368, pp. 59-68 : 60-65

Otiorhynchus (Nihus) grischunensis sp. n.

( Figs 1 & 3–4 )

Holotype ( Fig. 3 A): 1 Ƥ: 1st label: Switzerland, Passo del Bernina, 2100 m a. s. l., N799.000 / E143.000 [ Swiss coordinates], sifted from litter and mosses, 24.8.2001, leg. C. Germann; 2nd label: Otiorhynchus muelleri Rosh. det. P. Scherler 2001 [wrong determination]; 3rd label: Otiorhynchus (Nihus) spec. L. Magnano det. 03; 4th label (red): Holotype Otiorhynchus grischunensis des. C. Germann 2009 ( NMBE). Note that the spermatheca of the holotype has been lost.

Paratypes ( Figs 1 & 3 B): 2 Ex. 1 Ƥ: 1st label: “ Suisse, Grisons, s/St. Moritz [above St. Moritz], 2100 m [a. s. l.], 21.9.65 [1965], A. Comellini”; 2nd label: Paratype Otiorhynchus grischunensis des. C. Germann 2009 ( MHNG). 1 Ƥ: 1st label: „Davoser Berge, 2500 m [a. s. l.], Dr. Wolf, Schiahorn 14.9.1932; 2nd label: O. (s. str.) rhilensis Strl. , det. Behne 1993; 3rd label: bulgarische Art, Fundort verwechselt? [remark by Lutz Behne]; 4th label (red): Paratype Otiorhynchus grischunensis des. C. Germann 2009 ( MHNG).

Size: Length of body exclusive of rostrum, 3.3–3.5 mm.

Body colour: auburn to dark brown.

Head, rostrum and antennae: Colour auburn to dark brown. Rostrum covered with broad pale-brown scales, scales thinner towards rostral apex. Rostrum at insertion of antennae strongly bulged, half size of frons between eyes. Eyes bulged, protruding. Antennal scape strong, diverging in first fourth. First two segments of antennal funiculus longer than wide (L/B: 1st: 1.5–1.6; 2nd: 1.4–1.5), following five segments continuously broadened, wider than long (3rd: 0.8 to 7th: 0.5).

Pronotum: L/B: 0.8–0.85. Transverse, laterally strongly rounded, widest behind middle, more strongly constricted at front margin than at hind margin. Surface irregularly tuberculate, punctuate between tubercles.

Integument covered with adherent oval pale-grey scales, hardly longer than wide and raised rod-shaped scales, slightly diverging at apical third, scales four to five times longer than wide, arising from tips of tubercles.

O. rhilensis species group O. proximus species group

A) differences

- (rostrum longer) - (rostrum shorter)

- pronotum lengthend - pronotum rounded

- elytra lengthend - elytra rounded

- spiculum ventrale rounded (*) - spiculum ventrale concave/incised

- at high altitude in xeric habitats - mixted habitats (montane forests to alpine dwarf-shrub

heath)

- SE distribution (Caucasus, Turkey, Bulgaria, Greece, - NE distribution (Carpathian mountains to Austria and Dalmatia to Italy) and one species in Switzerland Italy)

B) species and subspecies

O. abruzzensis Stierlin, 1892 O. ardealicus Penecke, 1927 O. boroveci Magnano, 2001 O. carpathicus Daniel & Daniel, 1898 O. grischunensis sp. n. O. globulus Gredler, 1866

O. khatiparicus Davidian & Arzanov, 2006 O. hypsibatus Ganglbauer, 1896 O. leonhardi Reitter, 1903 O. noskiewiczi Smreczynski, 1959 O. meoticus Davidian & Arzanov, 2006 O. poianae Penecke, 1927

O. rhilensis Stierlin, 1888 O. praetutiorum Di Marco & Osella, 1998 O. uludagicus Magnano, 2001 O. proximus proximus, Stierlin, 1861 O. winkelmanni Magnano, 2004 O. proximus depauperatus Penecke, 1935

O. proximus iteratus Magnano, 2001

O. salassorum Magnano, 1979

O. sp. n. ( Di Marco & Osella 1998, i. l.)

Elytra: L/B: 1.25–1.26. Pear-shaped, shoulders rounded, widest slightly behind the middle. Integument covered with three types of pale-brown scales: (I) oval, hardly longer than wide, adherent, (II) small, short rod shaped raised scales, three times longer than wide, and (III) long raised rod-shaped scales, three to four times longer than wide, diverging at middle, arising from interspaces. Interspaces flat and loosely covered with mostly four rows of type I scales. Scales of type II arise between distinct punctures of striae.

Legs: Auburn coloured, densely covered with various types of pale-brown scales, all femora unarmed.

Spiculum ventrale, spermatheca and ovipositor: ( Figs 4 A–C)

Differential diagnosis: Otiorhynchus grischunensis belongs to the O. rhilensis species group with a more elongate elytra and a rounded (not clearly incised) anterior margin of the spiculum ( Fig. 4 ). Among external morphological characters and such (female) genitalic characters as the spiculum ventrale and spermatheca, O. grischunensis sp. n. shows great similarity to O. rhilensis ( Figs 1–3 ). Otiorhynchus rhilensis is known to be a polymorphic species ( Magnano, 1979, 2001a) comprising both, bisexual and parthenogenetic populations ( Magnano, 2004) and showing considerable variability ( Figs 3 C–F). At present, O. grischunensis is known only from females. The following morphological differences between O. grischunensis and O. rhilensis are based on comparison with O. rhilensis specimens from several localities (populations) to ensure the reliability of the traits used (Appendix 1).

O. grischunensis differs from O. rhilensis in:

- the pear-shape of the elytra with the shoulders completely rounded ( Fig. 1 ) in O. grischunensis (in O. rhilensis the shape varies from rounded to elongated and the shoulders are not completely rounded ( Figs 2 & 3 C–F))

- laterally, pronotum and elytra are swollen ( Fig. 1 ) (in O. rhilensis pronotum and elytra are flattened on the discal areas ( Fig. 2 ))

- the scales on the interspaces on the elytra are small, four scales easily cover the width (in O. rhilensis the scales on the interspaces are larger and usually three scales cover the width of the interspaces, in some specimens (Slavianka, S Goleschovo, Fig. 3 F), striae are completely covered with dense scales)

- the body (habitus) is generally larger and more rounded ( Fig. 1 ) ( O. rhilensis is smaller and more slender ( Figs 2 & 3 C–F))

- base of the spiculum ventrale is rectangular to trapezoid with basal branches converging at a sharp angle ( Figs 4 A–C) (in O. rhilensis the base is rounded with the angle of basal branches less sharp ( Figs 4 D–F) Bionomy: The holotype was collected by sifting mosses and lichens as well as leaf litter under dwarfshrub heath ( Rhododendron , Vaccinium ) above 2100 m a. s. l. ( Fig. 5 ). Together with O. grischunensis the following Curculionidae-species were found (ordered by dominance): Otiorhynchus pauxillus Rosenhauer, 1847 , O. pupillatus Gyllenhal, 1834 , O. varius Boheman, 1843 and Dichotrachelus imhoffi Stierlin, 1857 .

Derivation of Species Name: The name “ grischunensis ” is a Latinized adjective of the region where the species was found, the canton Grisons, in the written language Romantsch Grischun.

Figures

FIGURE 3. Habitus (dorsal) of Otiorhynchus (Nihus) spp., the four O. rhilensis specimens show the species' remarkable variability. A) O. grischunensis sp. n. holotype – Bernina; B) Dito, paratype – St. Moritz; C) O. rhilensis Stierlin, 1888 – SE-Rila, Belmeken; D) Dito – Stara Planina, Botev; E) Dito – S-Pirin, Orelek; F) Dito – Slavianka, S Goleschovo.

FIGURE 4. Spermathecae, spiculae ventrale and ovipositors of members of the O. rhilensis species group (A – F) and O. proximus species group (G – K). Right margin: the different shapes of the spiculum of both species groups are illustrated: rounded (above, O. grischunensis sp. n.) and concave / incised (down, O. proximus). A) Holotype Bernina (spermatheca lost); B) Paratype Davos, Schiahorn; C) Paratype St. Moritz; D) S-Pirin, Oelek; E) E-Rila, Belmeken; F) SE-Rila, Belmeken; G) Julian Alps; H) Wechsel; I) Styria; J) Rodna-Mountains; K) Vyosoke Tatry. Details concerning finding locations are indicated in Appendix 1.

FIGURE 5. Habitat of O. grischunensis sp. n. at the type locality on Pass of Bernina in Grisons above 2100 m a. s. l (photo: C. Germann).

FIGURE 1. O. grischunensis sp. n. paratype dorsal (above) and lateral view (down) – Davos, Schiahorn.

FIGURE 2. O. rhilensis Stierlin, 1888 dorsal (above) and lateral view (down) – E-Rila, Belmeken.