Xanthochorema johnwardi, Espeland & Johanson, 2008

Espeland, Marianne & Johanson, Kjell Arne, 2008, New species and descriptions of females of the New Caledonian endemic genus Xanthochorema (Trichoptera, Hydrobiosidae), Mémoires du Muséum national d'Histoire naturelle 197, pp. 79-98 : 87-90

Xanthochorema johnwardi n. sp.

Figs 24-35

MATERIAL EXAMINED. — New Caledonia. Holotype: male, branche sud, 22°08.344’S, 166°30.147’E, 42 m, 03.XI.2003, Province Sud, Dumbéa River, branche nord, 2.2 km SE summit loc 6. Light trap [KA Johanson] ( NRM, alcohol); 1 female, Provof Mt. Piditéré, 22°07.503’S, 166°29.899’E, 25 m, 21.I.2004, ince Sud, Tontouta River , 4.8 km WSW summit of Mt. Vulcain , loc 124, light trap [KA Johanson & C Pöllabauer] ( MNHN, 21°55.258’S, 166°19.895’E, 41 m, 15.XII.2003, loc 83, light alcohol). Paratypes: 1 female, same data as holotype, ex- trap [KA Johanson] ( NRM, alcohol) .

cept ( NRM, alcohol); 1 female, Province Sud, Dumbéa River,

DIAGNOSIS. — Xanthochorema johnwardi n. sp. is similar to X. nathaliae n. sp. but is easily distinguished in the genitalia by the knife-shaped coxopodite in lateral view, and in dorsal view by the truncate inner margin of segment IX. Females are distinguished by the shape of sternite VIII, which is nearly square with a broad posterodorsal protrusion in lateral view.

DESCRIPTION OF THE MALE (Figs 24-30). — Abdomen with internal gland situated in posterior part of sternite IV and anterior part of sternite V, connected to lateral filament on sternite V; filament about 2.5 x longer than sternite V; arising from antero-medial part of segment, oriented slightly posterodorsad; cylindrical along its length; sharply narrowing at about half-length; covered by microtrichia. Sternite VI with minute, pointed process arising posteriorly on segment and covered by microtrichia; in ventral view widely triangular.

Genitalia: segment IX, in lateral view, with nearly straight anterodorsal margin and strongly convex posteroventral margin with small pointed process; covered by setae posteroventrally; inner margin widely truncate in dorsal view; posterior margin distinctly produced medially and laterally in ventral view, with broad incision medially; posterior half setose, anterior margin slightly concave. Proctiger nearly straight, broad, slightly shorter than coxopodite in lateral view, widening slightly posteriorly, rounded at apex; apex incised in dorsal view, lateral margins nearly parallel, slightly widening at mid-length; lateral process of proctiger absent. Filipod cylindrical in lateral view, oriented posterodorsally, slightly curved ventrally, about three-quarters the length of coxopodite, apex club shaped, covered by long setae mostly on ventral margin; in dorsal view slightly sigmoid, posterior one-third straight. Preanal appendage very short, club shaped, covered by setae, running parallel with basal part of filipod. Parapod broad, short, directed slightly posteroventrally, apex pointed, strongly hooked ventrally; anteroventral margin triangular, with few setae. Gonocoxite harpago absent;

26-30

FIGS 24-30. Xanthochorema johnwardi n. sp., male. 24, abdominal segments IV-VI, lateral view. 25, pointed process of abdominal sternite VI, ventral view. 26, genitalia, lateral view. 27, genitalia, dorsal view. 28, genitalia, ventral view. 29, phallus, lateral view. 30, phallus, ventral view. Scale bars = 1 mm.

coxopodite in lateral view knife shaped, with nearly straight ventral margin and slightly convex dorsal margin; setae present postero-medially and along ventral margin; in dorsal and ventral views inwardly hooked, inner margins parallel, slightly undulate with anterior and posterior pair of teeth; lateral margins convex; ventral margins concave in ventral view, mesal area setose. Phallus slightly inversely sigmoid in lateral view, broadest at midway, slightly constricted at about two-thirds its length, internal folds at apex. Sperm channel cylindrical, slender, gradually narrowing posteriorly. Aedeagus in lateral view narrowly thorn shaped, curving dorsad; in ventral view narrowly cuspidate, parallel-sided along anterior half, slowly widening before narrowing towards undulate, rounded apex.

DESCRIPTION OF THE FEMALE (Figs 31-35). — Abdomen with a cylindrical filament on segment V, about 2 x longer than segment V, covered by microtrichia. Sternite VI with minute, pointed process arising posteriorly on the segment and being widely triangular in ventral view.

Genitalia: posterior margin of segment VII straight in ventral view, bearing long and short setae. Tergite VIII about one-third as long as tergite IX; in lateral view, irregularly rectangular, slightly pointed anteroventrally; in ventral view anterior margin slightly concave; posterior margin slightly convex, with pair of anterolateral rounded protrusions and about three setae laterally. Sternite VIII strongly sclerotized; in lateral view posterior margin with broad posterodorsal protrusion covering a small part of tergite IX; apex pointed, dorsal and anterior margins straight, ventral margin concave, thin setae present at apex; in ventral view, lateral margins distally slightly convergent, posterolateral corners produced posteriorly, postero-medially with pair of slightly sclerotized posterior lobes, rounded with mesal protrusion, covered by small setae. Segment IX nearly rectangular, apical half covered by setae, longest setae posteroventrally; in ventral view mostly covered by sternum VIII, slightly inwardly folded, fold setose. Soft segment X consists of two pairs weakly defined, rounded lobes, basal pair with small cercus. Spermatheca forms a composite structure within segments VII-IX; curved slightly upwards in lateral view; anterior part

33-35

FIGS 31-35. Xanthochorema johnwardi n. sp., female. 31, abdominal segments V-X, lateral view. 32, pointed process of abdominal sternite VI, ventral view. 33, genitalia, lateral view. 34, genitalia, dorsal view. 35, genitalia, ventral view. Scale bars = 1 mm.

with slightly sclerotized bands near the opening of ductus bursa copulatrix; in dorsal and ventral view posteriorly forming a rounded lobe; sclerotized dorsal part continues posteriorly into sclerotized, broad posterior process; deeply and widely incised posteriorly in dorsal and ventral views.

ETYMOLOGY. — This species is named after Dr. John B. Ward (Canterbury Museum, Christchurch, New Zealand) in recognition of his valuable contribution to Hydrobiosidae systematics and for describing Xanthochorema paniensis together with Nathalie Mary.