Geranomyia fuscior, Starý, 2012

Starý, Jaroslav, 2012, The identity of Geranomyia bezzii and a description of G. fuscior sp. nov. (Diptera: Limoniidae), Acta Entomologica Musei Nationalis Pragae 52 (1), pp. 273-279 : 277-278

Geranomyia fuscior sp. nov.

( Figs. 4–6 )

Material examined. HOLOTYPE: J ( SMOC): PORTUGAL: ALGARVE: Castro Marim , 0.3 km S, saltmarsh (24 m), 2.iv.2009, J. Starý leg. / HOLOTYPE, Geranomyia fuscior sp. n. [J], J. Starý 2011.

PARATYPES (20 JJ 12 ♀♀): ALBANIA: Durazzo [= Durrës], 30.v.1917, 1 ♀, Karny leg. ( NHMW) [listed by LACKSCHEWITZ (1928) as bezzii ]. PORTUGAL: ALGARVE: Castro Marim, 0.3 km S, saltmarsh (24 m), 2.iv.2009, 10 JJ 5 ♀♀, 4.iv.2009, 10 JJ 5 ♀♀, J. Starý leg. ( JKLE, JSOC, NMPC, SMOC). LIBYA: Tripolis [= Tarabulus], 17.vii.1906, 1 ♀, A. Klaptocz leg. ( NHMW) [listed by LACKSCHEWITZ (1928) as bezzii ].

Diagnosis. Extremely similar to G. bezzii in general appearance, but with thoracic patterning darker and more extensive. Stripes on mesothoracic dorsum shiny, very dark. Postscutellum mostly brown throughout. Tips of femora and tibiae with more pronounced darkenings. Male terminalia with ventral gonostylus distinctly longer and broader than in G. bezzii , with rostral prolongation more rounded at tip in dorsal aspect. Wing length 6.2–7.4 mm.

Description. Male. Terminalia ( Figs. 4–5 ) darkly pigmented. Tergite 9 roughly semicircular. Gonocoxite distinctly shorter than ventral gonostylus; ratio about 2: 3. Ventral gonostylus distinctly longer and broader than in G. bezzii , rather ovoid, with rostral prolongation shorter and stouter, more rounded at tip in dorsal aspect, and curved rather dorsoanteriorly. Dorsal gonostylus parallel-sided, tapered to point only shortly before apex. Aedeagal complex as in Fig. 5 , with aedeagus not as strongly downcurved at apex as in G. bezzii .

Female resembling male in general appearance. Female terminalia ( Fig. 6 ): Cercus moderate in length, slightly upturned, occasionally slightly longer than that of G. bezzii . Two parts of infra-anal plate generally convex at posterior margin and more rounded at outer edge than in G. bezzii . Genital fork with its central, more pigmented part not as long as in G. bezzii and, on average, somewhat broader.

Differential diagnosis. The two species, G. bezzii and G. fuscior sp. nov., may differ from each other in a few external characters, such as the patterning of the thorax (paler and less extensive in G. bezzii ), the length of legs (slightly shorter in G. bezzii ), and the length of the male tarsal claws (slightly longer in G. bezzii ). None of these features, however, can be a reliable criterion for species separation. Especially the pattern on the thorax varies greatly in intensity and extent in both species (except for the two small marks on the upper part of the pleuron, which are always shining dark brown to blackish), even within specimens from the same locality (see Portuguese material), and it can be diagnostic only for very pale specimens of G. bezzii and very dark ones of G. fuscior sp. nov. A predominantly brown postscutellum may be indicative for G. fuscior sp. nov. The two species can be best differentiated from each other based on the male terminalia. The ventral gonostylus is the most indicative structure. It is rather large in G. fuscior sp. nov., distinctly exceeding the length of the gonocoxite (ratio about 3: 2), ovoid, with the rostral prolongation of moderate length, somewhat rounded at the tip in dorsal aspect and curved dorsocaudally. In G. bezzii , the ventral gonostylus is shorter compared to the gonocoxite (ratio about 11: 9), more slender, rather conical, with the rostral prolongation longer, subacute at the tip in dorsal aspect and curved caudally (cf. Figs. 1 and 4 ). In G. fuscior sp. nov., the dorsal gonostylus is tapered to pointed tip only shortly before apex and the aedeagus is moderately downcurved at apex, whereas in G. bezzii , the dorsal gonostylus is gradually tapered to pointed tip and the aedeagus is strongly downcurved at apex. The female terminalia also provide some differences (cf. Figs. 3 and 6 ), but these should be thoroughly evaluated and combined with all available external characters. In the structure of the male terminalia, especially the outline of the ventral gonostylus, G. fuscior sp. nov. bears resemblance to G. unicolor Haliday, 1833 , but in the latter species, the ventral gonostylus is still broader, with a very short rostral prolongation and with rostral spines situated distinctly more apart ( Fig. 7 ), not to mention other characters, including external ones.

Etymology. The name of the new species (Latin fuscior = darker) refers to its body colouration, which is in general darker than that of G. bezzii . An adjective in nominative singular.

Distribution. Albania, Portugal, Libya. From my experience both species are rather common on saltmarshes in Portugal.

Figures

Figs. 1–7.1–3 – Geranomyia bezzii Alexander & Leonard, 1912 (Portugal:Alvor): 1 – male terminalia, general view, dorsally; 2 – male terminalia, aedeagal complex, lateral view; 3 – female terminalia, internal structures, ventral view. 4–6 – G. fuscior sp. nov. (paratypes; Portugal: Castro Marim): 4 – male terminalia, general view, dorsally; 5 – male terminalia, aedeagal complex, lateral view; 6 – female terminalia, internal structures, ventral view. 7 – G. unicolor Haliday, 1833 (England: Devon: Beer, coll. JSOC), male terminalia, gonostyli, dorsal view. Scale bar 0.25 mm.