Asiphonipponaphis vasigalla sp. n.

The new genus is named for the absence of siphunculi. “A” (Latin) means “absent”, “sipho” (Latin) means “siphunculi”, “nipponaphis” refers to its affiliation to the tribe Nipponaphidini.

In alatae, antennae 5-segmented, secondary rhinaria annular. Rostrum short, ultimate rostral segment shorter than second hind tarsal segment, with 2 pairs of primary setae and 1 pair of accessory setae. Abdomen with 5 pairs of spiracles, present on abdominal segments II–VI. Siphunculi absent in both fundatrix and emigrant alatae. Cauda knobbed, distinctly constricted at base. Anal plate bilobed. Legs normal. Tarsi 2-segmented, claws normal, first tarsal chaetotaxy of alatae 3, 3, 3. Fore wings of emigrant alatae with pterostigma narrow and long, distal margin of pterostigma forming almost a straight line with the hind margin, media unbranched, not united with cubitus, and two cubitus veins fused at base; hind wings with 2 obliques.

This new genus is unique in Nipponaphidini by its peculiar galls and morphological characters. Different from other saccate galls on Distylium, e.g. galls of Nipponaphis, its galls are located on the midrib of leaves and split at the tip when mature, forming a flower-shaped opening, while galls of Nipponaphis are located on twigs and usually open on the lateral wall of the galls when mature. It is related to Quadrartus Monzen for sharing several characters in alatae, such as spiracles present on abdominal segments II–VI (i.e. 5 on each side of abdomen), distal margin of pterostigma forming almost a straight line with the hind margin, but differs from the latter as follows: antennae 5-segmented (in Quadrartus: 4-segmented); media of fore wings unbranched (in Quadrartus: once branched); siphunculi absent (in Quadrartus: present). It is also related to Indonipponaphis Ghosh & Raychaudhuri. Both of them possess 5-segmented antennae in alatae and induce galls on the midrib of leaves of Distylium. But the new genus differs from Indonipponaphis as follows: abdomen with 5 pairs of spiracles (in Indonipponaphis: 4 pairs); media of fore wings unbranched (in Indonipponaphis: once branched); siphunculi absent (in Indonipponaphis: present).

Taxonomy of Nipponaphidini is mostly based upon the apterae on secondary hosts. The identification of alatae is much more difficult because of the vague descriptions and limited diagnostic characters. But not all species are known by both alate and apterous morphs. Thus identification of alatae, although confusing, is still very important to the classification of Nipponaphidini. Further observations of life cycles will probably reveal more gall causers on Distylium, and acquisition of more morphs will facilitate the taxonomic study and clear up the confusion.

China (Hunan, 28°17'23"N, 109°43'11"E, altitude 240 m).

The new species is named for the shape of gall. “Vas” (Latin) means “vase”, “galla” (Latin) means “gall”.

Fundatrix: Body oval, nearly round (Fig. 8), reddish brown and covered with thin white wax in life. For morphometric data see Table 1.

Body lightly sclerotized, pale in color. Antennae, ultimate rostral segment and legs brown. Head, thorax and abdominal segments I–VII completely fused. Dorsum smooth. Abdominal tergite VIII with dense spinulose imbrications. Spiracles oval, closed, on abdominal segments II–IV, spiracular plates light brown. Dorsal setae of body little, short and pointed. Head with 1 pair of cephalic, 1 pair of spinal, 1 pair of pleural and 1 pair of marginal setae; thoracic nota each with 1 pair of spinal, 1 pair of pleural and 2 pairs of marginal setae; abdominal tergites I–VI each with 1 pair of spinal, 1 pair of pleural and 1 pair of marginal setae; tergite VII with 1 pair of marginal setae; tergite VIII with 4 setae. Cephalic setae, marginal setae on abdominal tergite I and setae on tergite VIII 0.68 times, 0.61 times and 1.01 times as long as widest diameter of antennal segment III, respectively. Front straight. Eyes 3-faceted. Antennae 3- or 4-segmented (Fig. 1); 0.14 times as long as body. Length in proportion of segments I–III: 35 : 26 : 100+16, respectively. Processus terminalis 0.16 times as long as base of the segment III; very thin, basal width 0.47–0.57 times as long as apical width of base of the segment III. Setae on antennae sparse. Segments I–III each with 2, 2, 0+0 setae, respectively. Processus terminalis with 4 apical setae. Primary rhinaria small, round, protuberant and placed wide apart. Rostrum short and thick, not reaching mid-coxae. Ultimate rostral segment blunt wedge-shaped, 1.43 times as long as its basal width, 0.88 times as long as second hind tarsal segment; with 2 pairs of primary setae and 1 pair of accessory setae. Legs normal. Trochanters and femora fused. Hind trochanter and femur 2.11 times as long as the base of antennal segment III, hind tibia 0.15 times as long as body. Setae on legs sparse, fine and pointed. Setae on hind tibia 0.68 times as long as its mid-diameter. First tarsal chaetotaxy: 2, 2, 2. Siphunculi absent. Cauda, anal plate and genital plate with dense spinulose imbrications. Cauda knobbed, indistinctly constricted at base, 0.74 times as long as its basal width, with 9 setae. Anal plate bilobed, each with 9 or 10 setae. Genital plate broad round, with 2 anterior setae and 11 setae along the posterior margin. Two gonapophyses each with 3 or 4 short setae.

Alate viviparous females (emigrants from galls): Body oval (Fig. 9), cephalothorax black, abdomen dark reddish brown and pterostigma black in life, wings flat in repose. For morphometric data see Table 1.

Head, thorax, antennae, ultimate rostral segment, legs and genital plate brown, abdominal tergites VII–VIII with brown broad transverse bands, forewing veins and pterostigma brown, the other parts of body pale. Dorsum of head with sparse imbrications, tibiae, tarsi, venter of femora and abdominal tergites VI–VIII with dense spinulose imbrications. Spiracles oval, closed, on abdominal segments II–VI, spiracular plates brown. Dorsal setae of body short and pointed, on light brown seta-bearing sclerites. Head with 10–25 dorsal setae between antennae and 15–20 dorsal setae between eyes; pronotum with 1 pair of spinal, 1 pair of pleural and 2 pairs of marginal setae; mesonotum with 19–30 setae; abdominal tergite I with 5–8 spino-pleural and 1 pair of marginal setae; abdominal tergite II with 4–9 spino-pleural and 1 pair of marginal setae; abdominal tergite III with 6–8 spino-pleural and 1 pair of marginal setae; abdominal tergites IV–V each with 5–8 spino-pleural and 1 pair of marginal setae; abdominal tergites VI–VII each with 4–6 spino-pleural and 1 pair of marginal setae; tergite VIII with 5–8 setae. Cephalic setae, marginal setae on abdominal tergite I and spinal setae on tergite VIII 0.22–0.33 times, 0.29–0.53 times and 0.58–0.80 times as long as widest diameter of antennal segment III, respectively.

Head (Fig. 10): Front protuberant. Eyes compound. Antennae 5-segmented (Figs. 2, 11), with dense spinulose imbrications on segments III–V; 0.32–0.35 times as long as body. Length in proportion of segments I–V: 15 : 12 : 100 : 45 : 19+7, respectively. Processus terminalis 0.24–0.48 times as long as base of the segment V. Setae on antennae sparse. Segments I–V each with 1–3, 2, 0, 0, 0+0 setae, respectively. Processus terminalis with 5 apical setae. Primary rhinaria small, round and ciliated. Segments III, IV and base of segment V each with 37–44, 16–21, 6–9 annular secondary rhinaria, respectively. Rostrum short, not reaching mid-coxae. Ultimate rostral segment blunt wedge-shaped (Figs. 3, 12), 1.09–1.55 times as long as its basal width, 0.61–0.71 times as long as second hind tarsal segment; with 2 pairs of primary setae and 1 pair of accessory setae.

Thorax: Legs normal. Trochanters and femora fused. Hind trochanter and femur 1.21–1.48 times as long as antennal segment III, hind tibia 0.28–0.31 times as long as body. Setae on legs dense, fine and pointed. Setae on hind tibia 0.68–0.92 times as long as its mid-diameter. First tarsal chaetotaxy: 3, 3, 3. Dorso-apical setae on second hind tarsal segments expanded at apices. Empodial setae pointed, exceeding tip of claws. Fore wings (Figs. 4, 9) with pterostigma narrow and long, distal margin of pterostigma forming almost a straight line with the hind margin, media unbranched, not united with cubitus, and two cubitus veins fused at base; hind wings with 2 obliques.

Abdomen: Siphunculi absent. Cauda, anal plate and genital plate with dense spinulose imbrications. Cauda knobbed, distinctly constricted at base (Figs. 5, 13), 0.80–1.01 times as long as its basal width, with 12–19 setae. Anal plate bilobed (Figs. 6, 14), each with 10–15 setae. Genital plate broad round (Figs. 7, 15), with 39–52 setae. Two gonapophyses each with 3–9 short setae.

Holotype: alate viviparous female, CHINA: Hunan (Jishou City, 28°17'23"N, 109°43'11"E, altitude 240 m), 21 Apr. 2010, No. Y8974–1-8, on Distylium chinense, coll. X. T. Li (NZMCAS). Paratypes: 1 fundatrix and 11 alate viviparous females, with the same collection data as holotype.

The new species is similar to Indonipponaphis fulvicola Sorin, but differs from the latter as follows: Fundatrix: body larger, 2.036 mm long (the latter: about 1.250 mm long); first tarsal chaetotaxy: 2, 2, 2 (the latter: 3, 3, 2); siphunculi absent (the latter: present); cauda knobbed (the latter: round). Alatae from galls: base of antennal segment V with 6–9 secondary rhinaria (the latter: 11–14); abdomen with 5 pairs of spiracles (the latter: 4 pairs); first tarsal chaetotaxy: 3, 3, 3 (the latter: 3, 3, 2); media of fore wings unbranched (the latter: once branched); siphunculi absent (the latter: present); cauda knobbed (the latter: round).

Distylium chinense.

The aphids live in galls on the upper side of leaves of Distylium chinense. In early March, small galls start to grow on young leaves, often rise from or near the midrib, spherical, pale green, sometimes with a pinkish tinge due to the dense soft hairs on the surface (Fig. 16). Usually one leaf bears only one gall. After about 30 days, the galls when fully developed are large, long, saccate, approximately 3.2 cm in length and 1.1 cm in diameter (Fig. 17). Later, they split at the tip, forming a flower-shaped opening (Figs. 19, 20), through which large honeydew droplets coated with much wax are expelled (Fig. 18). The galls are vase-shaped when mature (Fig. 20). The alate viviparous females mature in the galls in late April and fly to an unknown secondary host.