Metrichia thomsonae Harris and Armitage, 2019

Harris, Steven C. & Armitage, Brian J., 2019, The Trichoptera of Panama X. The Quebrada Rambala drainage, with description of 19 new species of microcaddisflies (Trichoptera: Hydroptilidae), Insecta Mundi 707 (707), pp. 1-54 : 10-11

Metrichia thomsonae Harris and Armitage , new species

Fig. 9

Diagnosis. Metrichia thomsonae is placed in the campana group of Flint (1972) based on the presence of small dorsal pouches between abdominal segments VI and VII with closet similarity to that of M. lacuna (Bueno-Soria) and M. kocka Olah and Johanson in the lateral appearance of the inferior appendage. It differs from M. lacuna in the spinal apex of the phallus which is more similar to that of M. kocka . However, the phallus of the new species has a midlength process which is not present in M. kocka .

Male. Length 2.6–2.8 mm. Head without modification. Antennae simple with 19 segments. Body and unmodified wings brown in alcohol. Abdominal segments VI and VII with small round pouches dorsally; segment VII annular, with small ventromesal process. Segment VIII in lateral view wide dorsally, tapering ventrally; deeply incised ventrally. Segment IX triangular in lateral view, anterior portion within segments VII and VIII, posterior margin truncate. Preanal appendage (cercus) narrow in lateral view, tapering to rounded apex; in dorsal view narrow and angled inward, tapering to rounded apex; dorsolateral hook elongate in lateral view, narrow over length, gradually curving downward to acute apex; in dorsal view narrow over length, curving outward, subapical lateral point. Segment X membranous and triangular laterally; in dorsal view short and truncate posteriorly. Inferior appendages in lateral view quadrate, apical margin concave mesally, cluster of stout setae on inner posteroventral margin; in dorsal and ventral views rectanguloid, inner margins tapering distally to broad rounded apex, stout spines on inner posterior margin. Phallus tubular, elongate lateral process at midlength, apex bulbous in dorsal view with pair of apical spines, inner spine about half-length of outer spine, ejaculatory duct extending posteriorly between spines; in lateral view apical spines curving and diverging.

Female. Unknown.

Type material. Holotype, male—Panama, Bocas del Toro Province, Quebrada Rambala, near Rambala Jungle Lodge , 3.74 km SSE Rambala, 8.91627°N and 82.15469°W, 120 m, Malaise trap, March 31–April 11, 2015 E. Carlson ( COZEM) . Paratypes. Same data as for the holotype, 1 male ( SCH).

Etymology. We take great pleasure in naming this species for our colleague Dr. Robin E. Thomson, Curator of the University of Minnesota Insect Collection, for her work on Neotropical microcaddisflies, including those in Panama.

Figures

Figure 9. Metrichia thomsonae, sp. n., Male genitalia. A) Lateral view. B) Ventral view. C) Dorsal view. D) Phallus apex, lateral view. E) Phallus, dorsal view. F) Abdominal segments VI, VII, and VIII, dorsal view.