Agraylea dactylina Zhou, Yang & Morse, 2016, n. sp.
Creators: name: Zhou, Lei
name: Yang, Lian-Fang
name: Morse, John C.
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Trichoptera
Hydroptilidae
Agraylea
Agraylea dactylina

description: Agraylea dactylina n. sp.
(Fig. 1)
Diagnosis. The new species differs from those species whose distribution extends into the East Palearctic Region, such as A. sexmaculata, A. multipunctata CURTIS 1834, A. cognatella MCLACHLAN 1880, and A. taymyrensis MEY 2003, in having 1) inferior appendages that are stoutly triangular, with a broad base about 1/2 the height of segment IX in lateral view, with inner margins of each appendage concave and bearing a tiny tooth on the inner surface subapically in ventral view; 2) the basodorsal projections of the inferior appendages are absent; 3) the divided halves of dorsum IX each has its dorso-posterior end produced into a bilobed projection. However, in those 4 other species, the inferior appendages are elongate, each with its height only about 1/4-1/5 the height of segment IX in lateral view, the baso-dorsal projections of the inferior appendages are well developed; the inner margins of each inferior appendage is straight without any subapical teeth on the inner margin in ventral view, and the dorsoposterior ends of the divided tergum IX are not each produced into a bilobed projection. In addition, this new species is similar to A. multipunctata in the identical shape of the aedeagus and in the long subgenital plate, but differs from that species in that the inferior appendages are not divided, but each appendage is roundly incurved with a blunt tip in ventral view (each inferior appendage is divided into three lobes with the ventral lobe straight, acute at apex in ventral view in A. multipunctata). It differs from A. sexmaculata in having the tip of the subgenital plate extending as far as the apices of the inferior appendages and the spiral titillator circling the aedeagus 1.5 times with the distal half directed straight backward (the subgenital plate extends only to the mid length of the inferior appendages and the spiral titillator circles the aedeagus not quite 1.2 times in A. sexmaculata).
Male. Length of each forewing 4.2 mm (n=2), antennae 36-segmented. Ventral process on sternum VII long, with enlarged apex having tiny denticles (Fig. 1 F).
Male genitalia. Dorsum of IX completely divided, each half with dorso-posterior end produced into bilobed projection (bilob.d.pr.), with upper lobe bearing very tiny setae and with lower lobe slightly smaller in size and bearing long setae (Figs. 1 A, 1B); pleura IX about as long as high in lateral view, anterior margins straight, posterior margins each with deep posterodorsal and posteroventral indentations, forming broadly rounded posterolateral lobe on each side (Fig. 1 A). Tergum X reduced to short membranous lobe, nearly quadrate in dorsal view; triangular in lateral view, broad at base with dorsal margin sloping caudoventrad (Fig. 1 A). Inferior appendages massively triangular in lateral view, with broad base about 1/2 height of segment IX; in ventral view, each inferior appendage about 3.5 times as long as basal width, with inner surface concave, distal half curved mesad and gradually reduced to blunt tip and bearing tiny tooth subapically (Fig. 1 B, 1C). Profile of exposed portion of subgenital plate peach-shaped with single pair of setae on apicolateral edges, far from apicomedian projection in dorsal view (Fig. 1 B); full length of plate 3 times of its broadest width, with distal 1/3 tapering posteriorly to median ventral projection in ventral view (Fig. 1 C); in lateral view, distal half curved downward and narrowing to truncate tip extending nearly to apices of inferior appendages (Fig. 1 A). Aedeagus relatively short and stout with proximal and distal halves equal in length, spiral titillator circling aedeagus 1.5 times and with distal portion directed almost straight backward, apex of aedeagus slightly enlarged and bilobed (Fig. 1 D).
Holotype. Male; CHINA: Si-chuan Province, Kang-ding County, unnamed waterfall, tributary of Da-du River, 100 m upstream of G318 at 2824.9 km stone marker, N30.0665°, E102.1178°, alt. 1675 m, 29 Jun 2005, Coll. J.C. MORSE, CN 05062901 (Fig. 8). Paratype. Same data as holotype, 1 male and 13 females.
Etymology. Greek, dactylina = digitate, with reference to the thumb-like posterodorsal projections of segment IX.
Distribution. Oriental–Palearctic Boundary Region of China: Si-chuan.
Discussion. Discovery of this new Agraylea species from China is significant biogeographically as it extends the genus Agraylea distribution from Holarctic and Nearctic Regions to the Oriental Region at a latitude of N30.0665°. However, the type specimens of our new species were collected from an unnamed waterfall, a tributary of the Da-du River with its headwaters originating in the Ya-la Snow Mountains—This tributary passes through the Zhe-duo Snow Mountain, with an altitude of 1675 m a.s.l. about 30 km away from the collecting locality, such that the water temperature of this stream was relatively low. Perhaps we can classify this area as belonging to the Oriental–Palearctic Boundary Region.
description: Published as part of Zhou, Lei, Yang, Lian-Fang & Morse, John C., 2016, New species of microcaddisflies from China (Trichoptera: Hydroptilidae), pp. 203-219 in Zootaxa 4097 (2) on pages 204-206, DOI: 10.11646/zootaxa.4097.2.3, http://zenodo.org/record/265546