Pseudorthocladius sp.

Magoga, Giulia, Montagna, Matteo, Marziali, Laura, Rossaro, Bruno & Disaa, 2017, Revision of type and non-type material assigned to the genus Orthocladius by Goetghebuer (1940 - 1950), deposited in the Royal Belgian Institute of Natural Sciences (Diptera: Chironomidae), Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 57 (2), pp. 723-749 : 745

Pseudorthocladius sp.

( Figs 63‒68 )

Material examined. 1 ♁, pinned, now mounted on slide, labelled: ‘ Trissocladius nigerrimus Coll. et det. Goetgh. M. Goetghebuer // type locality: Tronchiennes, 24.III.1918 ’ and loaned by RBINS as O. nigerrimus .

Comments. We decided to analyze this species because, despite the pinned specimen being labelled as ‘ Trissocladius ’, it was in the same box of other Orthocladius: R.I.SC.N.B. _07_ Chir_11_Suppléments Déterminés. The name Trissocladius nigerrimus was made available by GOETGHEBUER (1919: 59) based on a ‘large number of pupal exuviae’ that he had collected ‘in a ditch at Tronchiennes, in March’. Later GOETGHEBUER (1921: 91‒92) described an unspecified number of adult males and females that he had sampled from ‘hundreds’ of specimens, the behavior of which he had observed before, during and after ‘ecclosion’ from a ditch at Tronchiennes on 24.III.1918 ( GOETGHEBUER 1921: 24‒25). GOETGHEBUER (1919, 1921) himself suggested the possible junior synonymy of T. nigerrimus with T. brevipalpis Kieffer, 1908 in KIEFFER & THIENEMANN (1908), and this synonymy has been the state of knowledge on the case ( ASHE & O’CONNOR 2012).

The examined male is labelled ‘ Trissocladius nigerrimus ’ and comes from the same type locality where GOETGHEBUER (1919, 1921) described the pupal exuviae and adults. Even if the specimen is very poorly preserved and the gonostyli have been lost, it cannot be assigned to Trissocladius , so it cannot be congeneric with the pupal exuviae figured in GOETGHEBUER (1919). It probably belongs to Pseudorthocladius , so it should represent a separate valid species. The antenna with a stiff seta (apparently broken at its tip), the wing with coarse punctation, the squama with about 18 setae and strongly curved Cu 1, the presence of pulvilli, the absence of tibial pseudospurs, and the anal point with strong setae suggest the inclusion in Pseudorthocladius . The specimen is in poor condition and we prefer not to describe it as a new species, because at present it is necessary to clarify the real status of T. nigerrimus .

Figures

Figs 63‒68. Pseudorthocladius sp. 63 ‒ eyes, 64 ‒ acrostichals, 65 ‒ pulvilli, 66 ‒ wing squama, 67 ‒ anal point, 68 ‒ inferior volsella.