In the Eocene, the extant genus Caladomyia occurred in the Palaearctic (Diptera: Chironomidae: Tanytarsini)

Abstract

ABSTRACT. The first fossil representative of Caladomyia SÄWEDAL, 1981, C. szadziewskii sp. n., is described from Eocene Baltic amber. The genus is so far known from extant species distributed in America, mainly in the Neotropical region.

The oldest known chironomids of the tribe Tanytarsini (Diptera: Chironomidae) indicate plesiomorphic character states

“…1D; Giłka et al, 2013: figs 1, 2, 4, 6, 7;Zakrzewska and Giłka, 2013: fig. 1) 4 -Dorsomedian extension of eye not developed; wing vein R 4+5 ending opposite or proximal of M 3+4 to wing apex (Fig.…”

“…The Tanytarsini have not been recorded in the Early Eocene amber of France dated back to $ 53 Ma Ma (Doitteau and Nel, 2007); thus the oldest Tanytarsini known to date are found in the Middle Eocene Baltic amber (40)(41)(42)(43)(44)(45). Phylogenetic relationships and systematic division within the tribe Tanytarsini are still unclear, as very few species of these dipterans have been reported from the fossil record so far (Seredszus and Wichard, 2007;Giłka, 2010Giłka, , 2011aGiłka et al, 2013;Zakrzewska and Giłka, 2013). On the one hand, this may be due to relatively low fossil species richness, but this may also result from the poor preservation of fossils and/or the troublesome preparation of minute amber inclusions and examination of very tiny diagnostic structures.…”

Molecular phylogeny and temporal diversification ofTanytarsusvan der Wulp (Diptera: Chironomidae) support generic synonymies, a new classification and centre of origin

“…The analysis was run with a topological constraint on Tanytarsus sensu lato as monophyletic to avoid sampled Cladotanytarsus species being placed in the ingroup. In addition, the internode including all sampled Caladomyia species was calibrated with a normal prior (initial = 34 Ma, mean = 35.6 Ma, stdev = 2 Ma) based on a stem fossil of Caladomyia dated to 37–34 Ma (http://fossilworks.org/?a=taxonInfo&taxon_no=287471) (Zakrzewska & Giłka, ). Described Tanytarsus species from amber (e.g.…”

“…The genus Caladomyia is largely Neotropical with a few species reaching the southern and southwestern USA (Säwedal, ; Trivinho‐Strixino, ). One extinct species is recorded from Eocene Baltic amber (Zakrzewska & Giłka, ). Adult males of Caladomyia can be separated from other genera by the posteriorly directed bars on the hypopygial anal point (Säwedal, ).…”

Towards the diversity of non-biting midges of the tribe Tanytarsini from Eocene Baltic amber (Diptera: Chironomidae)

“…This family has left fossil records since the Late Triassic (Krzemiński and Jarzembowski, 1999) with most taxa described from Eocene ambers. The fossil chironomid fauna found in amber from the Baltic region is the best studied one, including the so far oldest known members of the Tanytarsini -the tribe within the second largest subfamily Chironominae (Seredszus and Wichard, 2007;Giłka, 2010Giłka, , 2011aGiłka et al, 2013;Zakrzewska and Giłka, 2013, 2015b. According to the current division, the oldest Eocene Tanytarsini are represented by genera classified in two known subtribes: Tanytarsina (see couplets 10-17 in a key given below) and Zavreliina (couplets [18][19][20][21], with the exception of the extinct genera with unexplained subtribal position (couplets 3-9) (Zakrzewska and Giłka, 2014Giłka, , 2015b.…”