Apatidelia morsei Xu & Sun,

Xie, Yue, Wang, Beixin & Sun, Changhai, 2017, Associations and a new species of the genus Apatidelia (Trichoptera, Apataniidae) from China, European Journal of Taxonomy 333, pp. 1-20: 5-8

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Apatidelia morsei Xu & Sun

sp. nov.

Apatidelia morsei Xu & Sun  sp. nov.


Figs 2–5View FigView FigView FigView Fig



The new species is very similar to A. acuminata  in male genitalia, but differs from the latter in that (1) paired internal branches are finger-like, much shorter than those of A. acuminata  ; (2) each external branch is sinuate in dorsal view with its apex acute in the new species, but is arc-shaped with the apex obtuse in A. acuminata  ; (3) each inferior appendage is stout in ventral view in A. morsei  sp. nov., but is slender in A. acuminata  ; (4) FI is sessile in A. morsei  , but is petiolate in A. acuminata  . The new species can be separated from A. martynovi  by the external branches being sinuate with the apex acute in dorsal view, as in A. martynovi  it is arc-shaped with the apex bulging. It can easily be separated from A. gansuensis  by the distal segments of inferior appendages, which are acute apically, but bifurcate in the latter. It differs from A. egibiel  in the overall shape of the phallic apparatus. In addition, the new species can be separated from A. mirabilis  by sickle-shaped external branches in lateral view, by short internal branches, and by each distal segment being about twice the length of the basal segment.


The female of the new species is similar to Apatidelia acuminata  , but differs in that (1) the lateral margin of segment IX is depressed at mid-length in lateral view, but is straight in A. acuminata  ; (2) apicodorsal sclerites of the posterior lobe of IX are close to each other in dorsal view, but widely separated in A. acuminata  ; (3) lateral lobes of IX in ventral view are somewhat elliptical, but rectangular in A. acuminata  .


The species is named in honor of Dr John C. Morse from Clemson University, USA, for his contributions to the study of the world’s Trichoptera  .

Type material


CHINA: ♂, Mt. Dashan, Gaohong Town, Lin’an , Zhejiang Province, 119.62° E, 30.39° N, alt. 507 m, 11 May 2015, Jihua Xu and Yue Xie leg. (NJAU).



CHINA: 1 ♂, 2 ♀♀, Cheshuiwu, Lin’an, Zhejiang Province, 119.45° E, 30.36° N, alt. 538 m, 21 Oct. 2015, Jihua Xu, Yue Xie, Xiangjuan Wu, Lei Zhang and Zhen Liu leg. (NJAU).


Male ( Figs 2–4View FigView FigView Fig)

BODY LENGTH. 6.5 mm. Length of fore wing: 7.5 mm.

BODY. Head black; eyes grey, ocelli white; cephalic setal warts white; vertexal medioantennal compact setal warts irregular, length equal to width; vertexal lateroantennal compact setal warts widely separated, length greater than width; vertexal lateroantennal fragmented setal warts small, numbers varying; occipital setal warts large, elliptical ( Fig. 2View Fig). Prothorax and pterothorax black, with setal warts white. Fore wings brown, with numerous hairs; venation typical of the genus described by Mosely (1942), but without crossvein r in each fore wing ( Fig. 3AView Fig); hind wings pale, with 3 rod-like frenular setae at base of frenulum, each about 0.35 mm long ( Fig. 3BView Fig). Abdomen dark brown; abdominal sternum V with a short, finger-like lateral process on each side.

MALE GENITALIA. Segment IX annular; in lateral view ventral margin more than 2 times as long as dorsal margin, anterior margins arc-shaped, posterior margins somewhat straight, with posteroventral angle produced apically ( Fig. 4AView Fig). Segment X membranous. Each preanal appendages short and rod-like, setose. External branches sickle-shaped in lateral view, tapering from base to acute apex; paired internal branches thin and short dorsally, about ⅓ as long as preanal appendages ( Fig. 4BView Fig). Inferior appendages stout; basal segments of inferior appendages cylindrical in ventral view, each with base strongly sclerotized, bearing strong bristles; distal segments of inferior appendages lanceolar in lateral view and knife-like in ventral view, about 2 times as long as basal segments of inferior appendages, densely bristled on inner surfaces ( Fig. 4CView Fig). Aedeagus in ventral view with base bulging and apex divaricate, in ventral view middle portion slightly curved upwards, distal portion swollen; paired parameres in lateral view each divided into 2 branches at middle, dorsal branches slightly sclerotized, straight, sparsely setose, ventral branches shorter than dorsal ones, strongly sclerotized, slightly curved upwards ( Fig. 4View Fig D–E).

Female ( Fig. 5View Fig)

BODY LENGTH. 6.0 mm. Length of each fore wing: 6.0 mm.

BODY. Color resembles that of male, somewhat yellowish brown. Abdominal sternum V normal, without a lateral process on each side.

FEMALE GENITALIA. Sternum of segment VIII with a short vulvar lobe, somewhat finger-like in lateral view ( Fig. 5AView Fig) and triangular in ventral view ( Fig. 5CView Fig). Segment IX in dorsal view triangular, posterior lobe of IX with apex shallowly incised mesally, subapically with 2 rectangular sclerites; lateral lobes of IX developed, subrectangular in lateral view and elliptical in ventral view; lower lobe of IX in lateral view semicircular, in ventral view incised deeply. Segment X visible in lateral and ventral views, slightly sclerotized, roof-shaped in lateral view, rectangular in ventral view. Processus spermathcae triangular in ventral and lateral views, paired spermathecal sclerites hook-like, connected by an arc-shaped sclerite subapically ( Fig. 5View Fig B–C).




China (Zhejiang).