Allotrichia rhynchophyllum, Zhou, Lei, Yang, Lian-Fang & Morse, John C., 2016

Zhou, Lei, Yang, Lian-Fang & Morse, John C., 2016, New species of microcaddisflies from China (Trichoptera: Hydroptilidae), Zootaxa 4097 (2), pp. 203-219 : 206-208

Allotrichia rhynchophyllum n. sp.

( Fig. 2 )

Diagnosis. The new species is somewhat similar to Allotrichia pallicornis , the type species of this genus, in the general shape of male genitalia: 1) The anterior margin of segment IX has deep dorsal and ventral indentations forming an anterolateral lobe with a 70–75° angle on each side in lateral view; the posterodorsal margin is nearly straight. 2) The subgenital plate bears a pair of slender, dorsolateral projections. The new species differs from A. pallicornis in having 1) segment X rectangular, 2 times as broad as long in dorsal view; 2) the distal half of the subgenital plate strongly downcurved and with an acute apex in lateral view; and 3) inferior appendages with posterior margins slightly concave; whereas segment X is square, the subgenital plate is directed horizontally backward and with a blunt apex, and the inferior appendages have their posterior margins deeply concave in A. pallicornis .

Male. Length of each forewing 3.5 mm (n=1), antennae each 25-segmented. Ventral process on sternum VII long, with rough ventral surface in lateral view, subapically slightly concave, and with distal end enlarged in ventral view ( Fig. 2 E).

Male genitalia. Dorsum of segment IX completely divided, with transverse posterior margins nearly straight and aligned in dorsal view; pleura IX about 2/3 as long as high in lateral view, anterolateral margins protruding anterad in broadly rounded lobe forming a 70–75° angle on each side, upper posterolateral portion of pleura IX slightly concave and lower posterolateral portion protruding slightly backward forming blunt lobe with about 120° angle on each side ( Fig. 2 A). Tergum X rectangular, 1/2 as long as wide in dorsal view. Inferior appendages quadrangular, each with dorsal margin 2/3 as long as its ventral margin, and with posterior margin of appendage shallowly concave in lateral view ( Fig. 2 A); in ventral view, exposed portion of appendage almost quadrate, with posteior margin slightly concave ( Fig. 2 C); inner suface of appendage with many tiny, acute protuberances evenly spaced ( Fig. 2 B, larger arrow). Subgenital plate well developed with basal half extending laterally downward and forming rectangular lateral lobe on each side of plate ( Fig. 2 A, 2B), distal portion tongue-like in dorsal view, strongly downcurved with acute tip in lateral view ( Fig. 2 A); pair of slender, dorsolateral projections set on each side of mid distance of plate, small acute process visible in both dorsal and lateral views just below base of each slender lateral projection ( Fig. 2 A, 2B, smaller arrow in each). Aedeagus relatively short and stout with proximal half 1.5 times as long as distal half, spiral titillator circling segment 1.5 times with the apical portion directed straight backward, apex of aedeagus slightly enlarged and bilobed ( Fig. 2 D).

Holotype. Male; CHINA: Hei-long-jiang Province, Yi-chun City, Wu-yi-ling, Wu-yun River in the Town of Yong-sheng, N47.54°, E128.53°, alt. 160 m, 31 July 1993, Coll. SUN C-h.

Etymology. Neuter Greek noun rhynchophyllum = nose-leaf, used in apposition with the genus name with reference to the beak-like shape of the distal portion of the subgenital plate in lateral view. Distribution. East Palaearctic Region of China: Hei-long-jiang.

Figures

FIGURE 2. Allotrichia rhynchophyllum n. sp. male genitalia. A, left lateral; B, dorsal; C, ventral; D, aedeagus; E, ventral process of segment VII, left lateral. a. lat. lob. = anterior lateral lobe of IX; rec. b. pr. = rectangular basal projection of subgenital plate; sl. pr. = slender projection of subgenital plate; sub. g. pl. = subgenital plate; t. X = tergum X; IX = segment IX.