Cheumatopsyche Wallengren

Oláh, J. & Johanson, K. A., 2008, Generic review of Hydropsychinae, with description of Schmidopsyche, new genus, 3 new genus clusters, 8 new species groups, 4 new species clades, 12 new species clusters and 62 new species from the Oriental and Afrotropical regions (Trichoptera: Hydropsychidae), Zootaxa 1802, pp. 1-248 : 176-177

Cheumatopsyche Wallengren

Cheumatopsyche Wallengren, 1891: 142 . Type species Hydropsyche lepida Pictet, 1834 (monobasic). Hydropsychodes Ulmer, 1905 ; Kimmins 1963: 130.

Ulmeria Navás, 1918 ; Navás 1933a: 98.

Ecnopsyche Banks, 1913 ; Mey 1997: 306.

Plectropsyche Ross, 1947 , new synonym.

Ross (1947) indicated that Plectropsyche and Cheumatopsyche are closely related, only separated by the presence of hind wing fork 1 and in the forewing by the confluence of Cu2 and 1A at the wing margin. There are several Cheumatopsyche species from Madagascar having confluent forewing Cu2 and A1. The 2 characters are unstable and variable in most of the hydropsychine genera. Furthermore, the basic structure of the male genitalia of Plectropsyche is identical with that of Cheumatopsyche , involving the smooth, tongue-like, mesocaudal lobe or plate on segment X. Two species of the former genus Plectropsyche from Mexico belong to the Cheumatopsyche pali species group, established by Oláh et al. (2007).

Cheumatopsyche species are mostly uniformly brown or yellow small animals, while some species are dark with characteristic white pattern. Beside the characteristic combination of the primary generic characters Cheumatopsyche is easy to differentiate from all other hydropsychine genera by its characteristic genital structure involving a smooth mesoapical area, or tongue on segment X. Only the, possibly ancestral, Cheumatopsyche pali species group populating Madagascar and surroundings has elongating preanal appendages. In all other species groups the preanal appendages are smaller. Other apparently primitive states of the pri- mary generic characters in this group are: (5) hind wings m-cu present; (6) spur formula 244; and (7) hind wings forks 1235 present. There are 3 derived characters: (2) proepisternal setal wart absent; (3) forewing crossveins m-cu to cu situated closely; and (4) open hind wing median cell. Some of the secondary generic characters are variable also in this genus. There are 5–9 setal warts on the head. The male pretarsal claws have various shape, and are asymmetrical, laterally flanked by a bundle of setae in some species. However, there are species, mainly from Madagascar, with perfectly symmetrical pretarsal claws on all legs. The hind wing fork 1 is present or absent.

Cheumatopsyche is close to Potamyia , but the hind wing stem of M and Cu1 are neither parallel, nor close together in Cheumatopsyche , and in the genitalia the tongue-like mesoapical lobe is well developed in several Cheumatopsyche species groups and never present in Potamyia . The 5–9 setal warts on the head dorsum include a single fused pair of anteromesal (interantennal) setal warts; a pair of anterior (postantennal) setal warts sometimes being divided into anteromedian and anterolateral warts; a pair of mesolateral setal warts, frequently divided into 2 separate warts or even diffused into setal areas with several individual small warts; and a pair of posterior (cephalic) setal warts dominating on the entire dorsum.

In the genitalia segment IX is fused annularly, with less prominent apical lobe on the posterolateral margin. The dorsocaudal spiny lobes usually form a pair on the dorsolateral corners, the single ventrocaudal lobe, as derived character present only in unrelated species in several species groups. The dorsum of segment X is trilobed, with a smooth mesocaudal lobe, a tongue-like plate on the apicodorsal margin, and a pair of apicoventral setose lobes. The apicoventral setose lobes are developed into either paired processes, lobes, ridges, compact and diffused surfaces, or are secondarily fused. The smooth mesocaudal and the setose apicoventral lobes encircling the variously wide and deep dorsal and lateral interlobular gaps, visible in dorsal and lateral aspects. The reduction or fusion of the lobes on the segment X form the basis for delineating the various Cheumatopsyche species groups. Segment X has traverse and longitudinal sutures that usually meet anteriorly and forming an Y-shaped suture pattern. Apicodorsal setose areas or lobes are present in several hydropsychine genera ( Hydromanicus , Hydropsyche , Orthopsyche , Caledopsyche ), but present only in a single Cheumatopsyche species group (the C. holzschuhi species group). The gonocoxites are usually slender and the various shapes of the harpagones important diagnostically. The phallic apparatus is modified into a phallothecal tube with thick basis and simple apex formed by a pair of sclerotized endothecal processes, being the endothecal papillae or valvae sensu Schmid (1998) , or outer lip by McFarlane (1976), covering the heavily sclerotized phallotremal sclerites and highly reduced ventral membranous endothecal lobe.