24. Limnophilus incisus Curtis (Colpotaulius incisus McL.) 



Struck, 1899:117,-198; 1900, Figure 4. - Ostwald, 1901:107. -Struck, 

 1903:81-84, Plate I, Figure 6. - Siltala, 1904c: 29-31, Figure 6. - 

 Ulmer, 1909:262. - Lestage, 1921:707-712, Figures 243, 245. 



Full-grown larva. Length 15 — 17 mm. Frontoclypeus (Figure 409) 

 brown; wedge-shaped pattern and anterior part of sclerite with indistinct 

 punctation. Dorsal stripes as dark as in larvae of L. fuscicornis, 

 following frontal sutures but not always in contact with suture; posterior 

 „ part with short, transverse, rows of dots on stripes; lateral stripes brown, 

 with longitudinal rows of dots; space between stripes light brown. Ventral 

 surface light brownish, with rows of dots near the occipital foramen. 



Pronotum mainly yellow; dark areas brownish; transverse groove in 

 anterior third brown; posterior margin dark brown laterally; X- shaped, 

 median, punctate pattern and lateral groups of dots distinct. Mesonotum 

 usually darker in middle than laterally. Sclerites of metathorax brownish. 



Legs yellow, yellowish brown in some places, with dark punctation. 



Case 20 — 25 mm long, straight, slightly narrower posteriorly, made 

 of small, thin plant fragments of irregular form, sometimes with a few 

 sand grains. 



Pupa. Length 10 — 11 mm. Antennae filiform, reaching end of abdominal 

 segment 8; scape longer and thicker than other segments. Labrum yellow- 

 ish brown; setae as in forms described in preceding paragraphs. 



Wing sheaths rounded at end, reaching anterior margin of segment 5. 

 Midlegs natatorial; hind tarsi with sparse setae. 



Holding apparatus on segments 3 — 7; number of hooks: 111:1; IV:2; 

 V:2 + 7— 8; VI:2; 111:2. Gills as in larva. 



Anal rods thin, with slightly thicker end, curved dorsally, distal part 

 with small spinules laterally; all 4 setae black, small, 1st situated in 

 basal third, 2nd slightly more distally, 3rd and 4th subapically and apically. 

 Penis sheath broadly bipid, slightly longer than ventral appendages 

 (Figure 410). Cases as in larva. 



Mode of life and habitats. Spring species, in stagnant water 

 and slow rivers in plains. 



Distribution. The European USSR, Middle Asia, Siberia, Maritime 

 Territory, Kamchatka, Shantar Islands. In addition. Central and Northern 

 Europe, Pakistan. 



• Struck (1899: 117) states in his description of the larva of C olpotaulius incisus:... "Obwohl 

 dieselbe nicht zur Gattung Limnophilus gehort, so erscheint sie doch den eigentlichen Limnophili- 

 denlarven so konform organisiert, dass eine detaillierte Beschreibung derselben Hberflussig erscheint." 

 (Although this species does not belong to the genus Limnophilus, its larva resembles the true larvae 

 of.Limnophilidae so closely that a detailed description seems unnecessary.) The morphology of the larva 

 and pupa of this species does not show a single character that differs from the rather slight differences 

 between the larvae of the species of Limnophilus described above. Following American authors, 

 Schmid (1955: 130) made Colpotaulius Kolen. a synonym of the genus Limnophilus Leach. 

 The larva of L. incisus belongs to the group of dark-headed larvae of this genus. 



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