Phylloicus trichothylax, Prather, 2003

PRATHER, AYSHA L., 2003, Revision of the Neotropical caddisfly genus Phylloicus (Trichoptera: Calamoceratidae), Zootaxa 275 (1), pp. 1-214 : 98

Phylloicus trichothylax , new species

Fig. 103

Phylloicus trichothylax is known only from a single teneral male, and thus details of coloration are difficult to identify and the forewings are too twisted for accurate measurement. It is distinguished by the abdominal coremata, which consist of a pair of invaginated membranous pouches containing long setae and a single, eversible, digitate membranous lobe ( Fig. 103F ), and by the long digitate basodorsal process of tergum X ( Fig. 103A, B ).

Adult. Head golden brown, with dorsomesal crest of golden brown setae. Maxillary palps dark brown. Antenna golden brown. Dorsal pterothorax golden brown; ventrolateral thorax golden brown. Legs golden brown. Metathoracic leg of male with posterior fringe of long setae. Tibial spur formula 2,4,4. Forewing flat. Hind wing basal brush present in male.

Male. Preterminalic abdominal terga with anteromesal notch. Corematic structures present. Tergum IV with expanded lateral flanges, mesal coremata; mesal coremata an invaginated setose pouch, enclosing small, digitate eversible lobe. Tergum V without sclerotized modifications ( Fig. 103F ). Sternum VII without anteromesal process. Sternum VIII similar to anterior sterna, sternum IX not elongate. Tergum IX with paired mesal ridges extending length of segment; posterior margin smoothly rounded; thinly sclerotized anteromesally ( Fig. 103B ); lateral ridge present; dorsal pleural setae approximately 8, ventral pleural setae approximately 6 ( Fig. 103A ); sternum IX without mesolateral ridges; sternum IX ( Fig. 103C ). Preanal appendage shorter than tergum X, but greater than 2/3 length, narrowly elliptic, setae long, but not filamentous or longer than appendage ( Fig. 103A, B ). Tergum X without basal lobes; basodorsal process long and digitate; basolateral processes absent; apex, in lateral view, truncate, in dorsal view, entire ( Fig. 103A, B ). Harpago slightly tapered; peglike setae few, apical ( Fig. 103A, C ). Phallotremal sclerites average size, longest dimension less than diameter of phallobase; dorsal sclerite ovoid, in dorsal view horseshoe­shaped ( Fig. 103D, E ).

Female. Unknown.

Holotype male: ECUADOR: Cotopaxi: Latacunga , 13 km W, 1372 m, 1.vii.1975, Langley & Cohen ( NMNH).

Distribution. Ecuador.

Etymology. Trichothylax, from the Greek trichos, “hair” and thylax, “pouch,” for the setae­enclosing membranous pouch of tergum IV.

Figures

FIGURE 103. Phylloicus trichothylax. Male (holotype): A—lateral view; B—dorsal view; C— ventral view; D—phallus, lateral view; F—tergum IV, dorsal view.