Tanytarsus protogregarius

Zakrzewska, Marta, Krzemiński, Wiesław & Giłka, Wojciech, 2016, Towards the diversity of non-biting midges of the tribe Tanytarsini from Eocene Baltic amber (Diptera: Chironomidae), Palaeontologia Electronica (Ottawa, Ont.) 12 (1), pp. 1-21 : 11

Tanytarsus protogregarius

Giłka and Zakrzewska, 2015

Figure 6.1, 6.2

2015a Tanytarsus protogregarius Giłka and Zakrzewska in Zakrzewska and Giłka, p. 356, figures 7, 8 (male).

Material examined. Five adult males in 4 pieces of amber (Eocene, ~40-45 Ma , Gulf of Gdańsk, Figure 1 ) : 1 male ( CCHH 242-1 , 11 x 7 x 2 mm) ; 1 male ( CCHH 242-11 , 12 x 7 x 2.5 mm) ; 2 males as syninclusions ( CCHH 257-8 , 19 x 8.5 x 5.5 mm) ; 1 male ( CCHH 1754-12 , triangular 7 x 5 x 4.5 mm, Figure 6.1, 6.2 ) .

Remarks. The imagines of fossil species display a distinct variability in the structures that are diagnostic. These are difficult to define, among others, due to the usually small number of specimens examined. Below we present the features of the recently described male Tanytarsus protogregarius , which are subject to intraspecific morphological variability and may be the reason for incorrect identification (see also Tanytarsus serafini ). Figure 6.1 and 6.2 illustrate the atypical structure of the hypopygial anal point, observed in one of the five specimens examined (cf. Zakrzewska and Giłka, 2015a).

Figures

FIGURE 1. Tanytarsini - inclusions in Baltic amber from the Hoffeins collection (for details see Table 1 and Material examined).

FIGURE 6. Variations of diagnostic structures in males of Tanytarsus protogregarius (1, 2) and T. serafini (3-6). Hypopygium in dorsolateral aspect (1, 3, 5) and its structures magnified ca. 3-4 times (below): anal point (2, 4) and superior volsella (6).