Chironomus pe29

new form

Diagnosis (Reared specimens from original longistylus sensu Wülker material of B. Nagell.)
Exuviae 10.2mm long (n=2).
Colour: Contrast in colour between thorax and abdomen not so strongly marked: specimens dark anteriorly also have the abdomen infuscated; outer margin of the anal lobes coloured except at base.
Cephalothorax: Cephalic tubercles LxB 98x60µm (n=1). Frontal setae 40, 60µm long (n=2). Basal ring of thoracic horn 176x65-180x100µm; tracheal patch 120x40-140x50µm (n=); 12-13 tracheoles across; 3µm in diameter. Tracheolar patch of thoracic horn without an "eye". Thorax extensively granulate.
Abdomen: Hook row II entire, length of row 0.51/0.52x width tergite; hooks 90/104 (n=2). Armament of tergites II-VI not strongly waisted and with the posterior transverse band not successively increasing in extent to tergite VI; usually reduced on VI. Anterolateral points of tergites IV-VI not arranged in obvious transverse rows. Sternites III and IVwith lateral shagreen bands broadly joined anteriorly (the lateral bands may be reduced on IV). Pleura of segment IV spinulate, spinules 12µm long. Comb of segment VIII with 3/4 robust long-apiculate teeth, set on the end of an elongate ventral cuticular mound which exceeds appreciably the apico-lateral corner of the segment.
Anal segment: Anal lobe with 90-122 fringe taeniae (n=2).

Form keys out at Page 175: Chironomini 72 Chironomus of the Text Key.

(For more information see module IdentifyIt – file: Chironominae).

Ecological notes