Ecnomus niyomwasi Laudee and Malicky, 2018

Laudee, Pongsak & Malicky, Hans, 2018, Five new species of Caddisflies (Trichoptera: Insecta) from Upper Tenasserim Range, Thailand and Myanmar, Zootaxa 4524 (3), pp. 351-358 : 352-354

Ecnomus niyomwasi Laudee and Malicky n. sp.

Figs. 8–11

Type material. Holotype male ( PSUNHM). Myanmar: Tanintharyi Division, Myeik Province , Tanintharyi, Tanintharyi bridge, 12°05’27”N, 99°00’38”E, ca. 24 m a.s.l., 16 November 2016, leg. Pongsak Laudee.

Paratypes: Same data as holotype, 22 males: 7 males ( PSUNHM), 5 males ( CHM), 5 males ( CUAC), 5 males ( NMPC) .

Etymology. Named for Assoc. Prof. Dr. Sutham Niyomwas, who was the Director of the Research and Development Office, Prince of Songkla University, Hat Yai Campus.

Description. Length of each male forewing 4.0 mm; specimens in alcohol with head, thorax, forewings, abdomen, and legs light brown.

Male genitalia ( Figures 8–11 ). Segment IX constricted near midheight into tergum and sternum, with acute angle between them; tergum IX in lateral view long, anterior margins broadly and shallowly concave, posterior margin pointed dorsally; square with anterior U-shaped incision half its length; sternum IX long, ventral margin broadly convex, posterior margin truncate; in ventral view rectangular, with anterior V-shaped incision 1/4 its length. Superior appendages in lateral view somewhat rectangular, slightly tapering to round apex, with scattered setae apically; in dorsal view each parallel-sided with broad subbasal tooth and blunt apex. Segment X visible only in dorsal view, tiny, slender, bifurcate. Inferior appendages each with tuft of long setae subbasodorsally, hooked dorsad in apical half; in ventral view square basally, tapering to tubular apical half, bent mesad, blunt apically, space between pair of inferior appendages shaped like sacred fig leaf. Phallus tubular in lateral view, bifurcate basally, bent subapically, obliquely truncate apically.

Diagnosis. The male genitalia of E. niyomwasi n. sp. in lateral aspect appear similar to those of E. dikla Malicky 2009 found in Vietnam, but can be distinguished from them by the characters of inferior appendages. In E. niyomwasi n. sp., in lateral view the basal part of each inferior appendage is square, but is curved and tubular in E. dikla ; the apical part is significantly narrower than the apical part of an inferior appendage of E. dikla , which is more expanding. In ventral view the inferior appendages of E. niyomwasi n. sp. are square basally and tubular apically, but triangular in E. dikla .

Figures

FIGURES 8–11. Male genitalia of Ecnomus niyomwasi n. sp. 8, left lateral; 9, dorsal; 10, ventral; 11, phallus, left lateral. Inf = inferior appendage (paired), SIX = sternal portion of segment IX, Sup = superior appendage (paired), TIX = tergal portion of segment IX, X = tergum X.