New species of subgenus Tipula (Sivatipula) from China, with redescription of T. (S.) parvauricula and a key to all known species of the Oriental Region (Diptera, Tipulidae, Tipula)

Abstract Species of Tipula (Sivatipula) biprocessa sp. n. from Guangxi, China is described and illustrated as new in the subgenus Tipula (Sivatipula) Alexander, 1964. Tipula (Sivatipula) parvauricula Alexander, 1941 is redescribed and illustrated based on additional morphological characters. Semen pump of this subgenus is discussed. A key to all described species in this group is compiled.


Introduction
Tipula (Sivatipula) Alexander, 1964 is a small subgenus with Tipula mitocera Alexander, 1927 from the eastern Himalayas, India as its type species. The other species in this subgenus include T. (S.) pullimargo Alexander, 1951 from Myanmar, T. (S.) alhena Alexander, 1953 from Thailand, T. (S.) filicornis Brunetti, 1918 and T. (S.) bhishma Alexander, 1964 from India, T. (S.) lackschewitziana Alexander, 1928, T. (S.) suensoniana Alexander, 1940 and T. (S.) parvauricula Alexander, 1941 from China (Oosterbroek 2015). All these species are restricted to the Oriental region. The Chinese fauna of Tipula (Sivatipula) is poorly represented with only three known species. This subgenus is characterized by the following characters: male with antennae very long, slightly shorter, equal to or longer than body length, female with antennae relatively short, not beyond half length of body, flagellomere covered with six or seven long strong verticils; wing with squama naked, outer wing veins scattered with small, abundant macrotrichia, R 1+2 entire, Rs longer than m-cu; ninth tergite and sternite fused, median region of sternite extensive, more or less protrudent, forming amembranous extension; inner and outer gonostylus irregularly varied in shape. The species of subgenus Tipula (Sivatipula) had been placed previously in subgenus Tipula (Acutipula) Alexander, 1924, but treated subsequently as a distinct group based on the combined structural characters of antennae, hypopygium, and wing (Alexander 1964).
A previously unknown taxon of Tipula (Sivatipula) was noticed while sorting crane flies specimens collected from Leigongshan Mountain, Guizhou Province, and Cenwanglaoshan Mountain, Guangxi Zhuang Autonomous Region, China. In the present paper, the new species is described and illustrated, and a key is provided for separating all known species. Tipula (S.) parvauricula is redescribed based on newly available morphological characters with detailed illustrations. The original description of this species is insufficient and the illustrations are too simple to reveal necessary characters. The character of semen pump of subgenus Tipula (Sivatipula) is described for the first time. The current study also demonstrated the new distribution pattern for the subgenus Tipula (Sivatipula) in both Guangxi Zhuang Autonomous Region and Guizhou Province. Future collecting and investigation would undoubtedly increase the species numbers and range extension of this group in China.

Material and methods
The genital segments of the specimens were soaked in 10% NaOH overnight and observed or drawn in glycerine using a Leica MZ125 (Leica, Germany) stereomicroscope. The genital segments were then preserved in glycerine in 0.20 ml centrifuge tubes. Photographs of partial body of male were taken by Canon 5D Mark II digital single lens reflex camera (Canon, Japan) with MP-E 65mm f/2.8 1-5X macro lens (Canon, Japan). All measurements are in millimeters (mm), made with the aid of a digital caliper. The terminology and methods of description and illustration follow those of Alex-ander and Byers (1981) and Frommer (1963). The type specimens of the new species are deposited in the animal specimen room, School of Life Sciences, Anqing Normal University, Anqing, Anhui Province, China.
The key was principally constructed from descriptions in the literature without examination of the type species of most of these species, and should be considered preliminary. The characters used in the key rely primarily on the structures of genitalia and the length of antenna of male specimens.

Diagnosis.
Generally orange-yellow in coloration; antenna distinctly longer than body; prescutum orange-yellow with three light brown stripes, sometimes not clear; wings pale brown with a dark brown stigma; abdomen orange with segments six and seven black; hypopygium orange, tergite nine divided by a V-shaped notch, produced into a pair of ear-like processes, sometimes terminated into spinous point, ventral-lateral portions of tergite nine projected into two lobes, densely covered with black setae. Head orange. Rostrum orange with distinct orange nasus. Marking of vertex absent ( Fig. 1). Eyes black (Fig. 1). Antenna: 12-segmented, distinctly longer than body; scape orange, expanded apically; pedicel orange, short; flagellomeres dark brown, each flagellomere cylindrical and subequal in length, with abundant black verticils, longest one longer than one third of flagellomeres length. Palpi light brown.
Abdomen orange with segments six and seven black. Hypopygium orange, broad, compressed (Figs 5-6). Tergite nine separated by a V-shaped notch in ventral view; gradually narrowed to apex, produced into a pair of ear-like processes, sometimes terminated into spinous point in lateral view; ventral-lateral portions of tergite nine pro- jected into two lobes, densely covered with blackened setae (Figs 5-7). Sternite nine broader than tergite nine, median region of sternite nine protruded to a membranous extension (Fig. 6). Outer gonostylus flattened, widened medially, with a slender rod on ventral-lateral margin, directed dorsally (Fig. 6). Inner gonostylus broad basally, gradually narrowed to apex, rounded with a process truncated apically, ventral margin with a horn-shaped projection, dorsal margin with a finger-like process, basal region of inner gonostylus with a pyramidal process (Fig. 8).
Semen pump with compressor apodeme V-shaped, the arms expanded at apex (Fig.  11). Posterior immovable apodeme with only one arm, distinctly longer than compressor apodeme, gradually narrowed to apex and curved cephalad in lateral view (Fig. 9), sometimes abruptly bent to ventral margin (Fig. 10), the arm deeply grooved in dorsal view. Anterior immovable apodeme flattened, shorter than compressor apodeme, gradually narrowed to apex in lateral view (Figs 9-10). Aedeagus elongated, tubular, at least ten times longer than semen pump (Fig. 6).  (Alexander 1941), the prescutum is unmarked and the tergite nine is terminated into a pair of spinous points in lateral view. After observing five specimens, we noticed that the prescutum generally has three light brown stripes and the spinous point on tergite nine is not always present.
Three types of semen pumps were defined by Frommer (1963) based on morphological studies of the reproductive system of North American crane flies. Type III is the most common type characterized by the strongly bowed intromittent organ and by posterior immovable apodeme generally with two arms (Frommer 1963). According to the overall morphology, the semen pump of T. (S.) parvauricula should belong to Type III. However, its posterior immovable apodeme has only one arm, which differs from the results in previous works in Chinese species ( Diagnosis. Generally straw-yellow; prescutum straw-yellow with three light brown stripes; wings pale brown with a dark brown stigma; abdomen bright yellow on basal three segments, gradually changed to light brown on apical ones, segments six and seven suffused with black; hypopygium straw-yellow, tergite nine rounded at posterior Head straw-yellow (Figs 12-13). Rostrum light brown with a light brown nasus. Vertex without marking (Fig. 12). Eyes black (Fig. 12). Antenna: 12-segmented, distinctly longer than body; scape light yellow, expanded apically; pedicel light yellow, short; flagellomeres light brown, each flagellomere cylindrical, subequal in length, with abundant black verticils. Palpi light brown.
Semen pump with compressor apodeme V-shaped, the arms expanded at apex, distinctly broader than that of T. (S.) parvauricula (Fig. 22). Posterior immovable apodeme with one arm, distinctly longer than compressor apodeme, gradually narrowed to apex and curved cephalad in lateral view, the arm deeply grooved in dorsal view, basal region distinctly wider than that of T. (S.) parvauricula (Figs 22-23). Anterior immovable apodeme flattened, gradually narrowed to apex in lateral view (Fig. 22). Aedeagus elongated, tubular, at least ten times longer than semen pump.
Remarks. We compared the new species with all known species based on published descriptions and illustrations, and found that it is mostly similar to T. (S.) parvauricula by the color of body, the structures of antenna and hypopygium. It can be easily distinguished from the latter by the shape of tergite nine which is rounded at posterior margin with two distinct finger-like processes. The latter species has its tergite nine separated by a V-shaped notch with two short truncated processes and produced into a pair of ear-like processed ventrally. There is also a noticeable difference in the shape of the outer gonostylus which is simple and narrowed in the new species, but flattened and widened medially with a slender rod on ventral-lateral margin in that of T. (S.) parvauricula. Distinct interspecific difference is also found in the shape of inner gonostylus as Figures 8, 19 and 20.
Etymology. The specific epithet is a noun derived from the Latin 'processa' with Latin prefix 'bi', referring to the presence of two finger-shaped processes at posterior margin of tergite nine.