Chapter 1 - Núria BONADA

Chapter 6
11- Rhyacophila pascoei McLachlan, 1879
MATERIAL STUDIED: 1L
Guadalfeo Basin: GU16
DISTRIBUTION AND ECOLOGY
Central and southern European species. In the Iberian Peninsula it has been recorded in
central and southern basins (González et al., 1992).
This species has been found in rivers with high contents of sulphates and carbonates
concentrations in southern basins (García de Jalón & González del Tánago, 1986). In our
sampled basins, larvae of Rh. pascoei was found in a middle reach of a siliceous basin
with a fair biological quality.
12- Rhyacophila relicta McLachlan, 1879
MATERIAL STUDIED: 39L
Ter Basin: T10, T12
Tordera Basin: ToM9
Llobregat Basin: L42, L54, L64, L68, L60a, L67
DISTRIBUTION AND ECOLOGY
Endemic species from the Iberian Peninsula and Pyrenees.
This species has been found very abundant in middle rivers (see Vieira-Lanero, 2000). We
also have recorded it in headwaters but infrequent. According to González del Tánago &
García de Jalón (1984) Rh. relicta is an intolerant species to pollution.
13- Rhyacophila gr. tristis Pictet, 1834
MATERIAL STUDIED: 102L, 6♂ (V, VII, VIII)
Ter Basin: T2, T3, T5, T8, T10, T11, TM4, TM5
Tordera Basin: ToM13
Besòs Basin: B32
Llobregat Basin: L44, L45, L54, L56, L60a
Noguera Ribagorçana Basin: OUT0m, OUT200m, INLET
Júcar Basin: JU7
TAXONOMIC REMARKS
The imago found in Mongrony River (Oriental Pyrenees) has several taxonomic features
similar to Rh. aquitanica cited by Navás in closer areas (see González et al., 1992).
However, this specimen has been considered as Rh. gr. tristis because the absence of key
characters to differentiate both species with certainty and the high variability known in
Rh. tristis males (M. A. González, pers. comm.). In the same way, there are difficulties to
distinguish larvae of Rh. tristis and Rh. aquitanica. Buholzer (1978) observed that Rh.
tristis does not present ventral transversal stripes in the cephalic capsule, whereas Rh.
aquitanica does. In the northwest of Spain, where only Rh. tristis has been found, larvae
present transversal stripes (R. Vieira-Lanero, pers comm.), as in our specimens.
Consequently, we have included all specimens into the Rh. gr. tristis.
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