Medium-sized to large, up to 18 mm long. Red to dark red larvae.
Frontal apotome separated from narrower clypeus (with or without seta SIII on the sclerite); anterior margin of frontal apotome often strongly concave; labrum present, remaining labral area variably fragmentary.
Antenna with 5 segments, diminishing in size distally Lauterborn organs about half as long as segment 3, opposite on apex of 2nd segment, with style. Ring organ in proximal 1/3 of segment 1, seta absent. Blade substantially shorter than flagellum, accessory blade 50-100% length of segment 2.
SI plumose to toothed on both sides; SII simple; SIII short, slender; SIV normally developed. Seta praemandibularis simple. Labral lamellae normally pectinate, or consisting of only 9 or so teeth (species group C). Pecten epipharyngis simple with distal teeth and numerous denticles on surface, or few variably long distal teeth and no surface teeth. Premandible with 2 teeth and beard.
Mandible with pale dorsal tooth except in species group C; apical tooth slender, with 3 inner teeth. Pecten mandibularis modestly developed, lamellae simple. Seta subdentalis inserted on ventral surface, simple, leaf-like, or long and slender. Seta interna inserted on dorsal surface, plumose, 4-5-branched.
Mentum with simple median tooth, with or without lateral crenations, 6 pairs of lateral teeth on each side, with 4th lower than line of even decrease in size laterally. Ventromental plates separated medially by 0.5-1.5 width of median mental tooth, with smooth to finely toothed anterior margin; striae continuous. Setae submenti simple - long and slender or short and thick.
Lateral tubules absent, ventral tubules short to quite long in some species of groups A and B.
The generic diagnosis reflects the fact that species with very heterogeneous larval characters are included in Glyptotendipes. The genus is probably paraphyletic. It is possible to discern 3 groups, which are designated in the key as species groups A, B and C.
Species group A contains species with large, up to 18 mm long, larvae. They live predominantly in sediment or in "Aufwuchs". The group more or less corresponds with the subgenus Phytotendipes Goetghebuer as used by Lenz (1954-1962a).
Species group B contains species with smaller larvae, up to about 12 mm long, which are predominantly miners in living aquatic plants. Lenz (1954-1962a) assembled these species into the subgenus Phytochironomus Kieffer. Immature stages of the only currently known European representative of species group C, G. varipes, were first described by Shilova (1969a). A second species, G. ? amplus is known from North America. The larval characters differ so strikingly from those of the other 2 species groups that a new genus must eventually be erected for species group C. Since this can only be achieved in conjunction with a revision of Glyptotendipes, use of the subgeneric names Phytochironomus and Phytotendipes is avoided in favour of the taxonomically neutral term species groups.
Species groups of Glyptotendipes
- 1. Frontal apotome without pit, anterior margin strongly concave. Clypeus absent. Antennal segment 3 at least 3x longer than broad. Mandible with dorsal tooth plumose ... 2
- -- Frontal apotome with long oval subapical depression, anterior margin straight or convex. Clypeus present. Antennal segment 3 only slightly longer than broad. Mandible without dorsal tooth. SI palmate ... Species group C (varipes Goetghebuer, ? amphis Townes)
- 2. Labral sclerite 1 rectangular, posterior margin with a hardly discernible, semicircu lar pit. Accessory blade and style only about 1/2 as long as antenna] segment 2 or 3 respectively Middle tooth of mentum laterally crenate; ventromental plates separated medially by about 1.5x width of middle tooth of menturn. Setae submenti long, slender Larvae large, up to 18 mm long ... Species group A (includes barbipes Staeger, pallens Meigen, paripes Edwards)
- -- Labral sclerite 1 strongly concave posteriorly. Accessory blade and style about as long as antennal segment 2 or 3 respectively. Middle tooth of mentum simple, not crenate; ventromental plates almost contiguous medially, separated by only 1/2 width of median mental tooth. Setae submenti short and thick. Larvae smaller, up to about 12 mm long ... Species group B (includes caulicola Kieffer, fodiens Kieffer, severini Goetghebuer)
Larvae of Glyptotendipes occur in detritus-rich littoral sediments and in "Aufwuchs" of lakes, ponds, small water bodies and running water. A considerable proportion of species are "semi-miners" under the bark of submerged branches, in colonies of Bryozoa and sponges or mine in leaves and stems of submerged plants or plants with floating leaves. Only exceptionally (G. barbipes) occurring in brackish water.
Distributed throughout the temperate Holarctic with about 25, in part very doubtful, species. Six unconfirmed species are known from the Oriental region, one (unpublished) from the Afrotropical region.