Toxoptera chaetosiphon, Qiao & Wang & Zhang, 2008

Qiao, Gexia, Wang, Jianfeng & Zhang, Guangxue, 2008, Toxoptera Koch (Hemiptera: Aphididae), a generic account, description of a new species from China, and keys to species, Zootaxa 1746, pp. 1-14 : 5-7

Toxoptera chaetosiphon sp. nov. ( Figures 1–43)

Locus typicus. China (Guangxi)

Etymology. The species is named for its siphunculi with hairs. chaeto (Latin) means hairs; siphon (Latin) means tube.

Description

Apterous viviparous females: Body elliptical ( Fig.18). General measurementssee Table 1.

Mounted specimens: Head. Vertex convex, antennal tubercles slightly developed. Dorsal hairs of head many, fine, and with developed small tubercles at bases. Head with 1 pair of cephalic hairs, 3 pairs of antennal tubercular hairs and 16–22 dorsal hairs ( Figs. 1, 19). Antennae 6-segmented, segments I–II dark brown, segments III–VI brown and with spinulose imbrications; 0.6 times as long as body. Length in proportion of segments I–VI: 29–34, 27–30, 100, 67–87, 73–83, 38–44+88–102. Processus terminalis 2.3–2.5 times as long as basal part of the segment ( Figs. 3, 21). Antennal hairs acute, segments I–VI each with 3–9, 4–9 15–18, 6–10, 7–10, 2 or 3 +0–3 hairs, respectively, apical part of processus terminalis with 0–3 hairs. Length of hairs on segment III 0.07–0.08 mm, 1.8–2.3 times as long as diameter of segment. Primary rhinaria ciliated. Rostrum long wedge-shaped, apical part dark brown, reaching hind coxae or abdominal segment I; ultimate rostral segment 2.7–3.4 times as long as basal width ( Figs. 4, 22), 1.7–1.9 times as long as second hind tarsal segment; with 4 pairs of hairs, including 1 pair of accessory hairs.

Thorax. Dorsal and ventral cuticle with polygon reticulations. Mesosternal furca with separated arms ( Figs. 5, 23), length of single arms 0.10–0.12 mm, 0.4–0.5 times as long as antennal segment III. Spiracles elliptical, open or closed; spiracular plates dark brown. Marginal tubercles on prothorax transparent ( Figs. 6, 24), c.1.5 times as long as their basal width. Dorsal hairs on thorax many, fine, and with tuberculate bases; pronotum with 4 pairs of spinal, 1 pair of pleural and 2 pairs of marginal hairs. Legs normal. Distal half of femora, and basal part of tibia dark brown, others brown. Hind femur 2.0–2.2 times as long as antennal segment III, hind tibia 1.0–1.1 times as long as body. Hind tibia with 9–12 peg-shaped spines ( Figs. 12, 30), on basal two-thirds of inner side. Length of hairs on hind tibia 0.07–0.08 mm, 1.2–1.7 times as long as middle diameter of the segment III. First tarsal chaetotaxy: 3, 3, 2. Second tarsal segments with transverse imbrications.

Abdomen. Abdominal segments IV–VI with ventro-lateral spinulose ridges ( Fig. 13). Marginal tubercles on abdominal segments I–III ( Figs. 7–8, 25–26) and VII ( Figs. 9, 27) transparent, which on abdominal segments I and VII c.1.6 times and c.2.5 times as long as their basal widths, respectively. Dorsal hairs of body many, fine, and with tuberculate bases, and most dorsal hairs with brown sclerotizations at bases. Abdominal tergite I with 34–56 hairs, tergite VIII with 4–6 hairs. Length of marginal hairs on abdominal tergite I and dorsal hairs on abdominal tergite VIII ( Figs. 11, 29) 0.07–0.08 mm, 0.06–0.09 mm, 1.8–2.5 times and 1.5–2.2 times as long as widest diameter of antennal segment III, respectively. Siphunculi dark brown, barrel-shaped with spinulose transverse imbrications, 1.0–1.9 times as long as basal diameter, 0.5–0.7 times as long as cauda with 6–8 long and pointed hairs ( Figs. 14, 31). Cauda dark brown with dense spinules; taper, constricted in middle, 1.6–2.1 times as long as its basal diameter, with 17–28 hairs ( Figs. 15, 32). Anal plate broad round, with dense spinules and 20–26 hairs ( Figs. 16, 33). Genital plate transversely oval, with dense spinules and 21–30 hairs, including 6–9 anterior hairs ( Figs. 17, 34).

Alate viviparous females: Body less rotund than in apterae ( Fig. 36), 1.43–1.64 mm long, and 0.53–0.67 mm wide.

Mounted specimens: Head with 30–32 dorsal hairs ( Fig. 40). Length of cephalic hairs and dorsal hairs on abdominal tergite VIII 0.05–0.07 mm, 0.06–0.07 mm, 1.5–1.8 times and 1.7–1.9 times as long as widest diameter of antennal segment III, respectively. Antennae 6-segmented ( Figs. 37–38, 41–42), 0.7–0.8 times as long

as body; length in proportion of segments I–VI: 25–31, 24–27, 100, 72–78, 74–86, 38–47+103–132; processus terminalis 2.3–3.3 times as long as the base of the segment. Antennal segments I–VI each with 5, 6–7, 15– 18, 8–10, 8–9, 3+3 hairs, respectively, apical part of processus terminalis with 3 hairs. Length of hairs on segment III 0.05–0.06, 1.3–1.8 times as long as width diameter of the segment. Antennal segments III with 5–7 round secondary rhinaria. Rostrum reaching abdominal segment I, ultimate rostral segment 2.3–3.7 times as long as its basal width, 1.9–2.1 times as long as second hind tarsal segment; with 4 pairs of hairs, including 1 pair of accessory hairs. Thorax dark brown. Abdomen tergites VII and VIII with postsiphunlar patches and cross bands, other tergites without dorsal patches. Dorsal hairs of body without obvious scleroites at bases. Legs normal. Hind femur 1.6–1.8 times as long as antennal segment III, hind tibia 0.6 times as long as body. First tarsal chaetotaxy: 3, 3, 2. Veins of wings and pterostigma dark brown. In fore wings ( Fig. 36) media twice-branched. Siphunculi 1.5–1.8 times as long as basal diameter, about 0.7 times as long as cauda, with 5 or 6 long and pointed hairs ( Fig. 43). Cauda taper, slightly constricted in middle, 1.6–2.0 times as long as its basal diameter, with 20–23 hairs ( Fig. 39). Anal plate broad round, with 21 or 22 hairs. Genital plate with 19 or 20 hairs. Other characters same as apterous viviparous female.

Alatoid nymph: Body smaller than in apterae ( Fig. 35), 1.52 mm long, 0.71 mm wide.

Mounted specimens: As in alate vivipara, but: Head with 15 dorsal hairs. Length of cephalic hairs and dorsal hairs on abdominal tergite VIII 0.11 mm, 0.09 mm, 2.2 times and 1.7 times as long as widest diameter of antennal segment III, respectively. Antennae 6-segmented, 0.6 times as long as body. Length in proportion of segments I–VI: 37, 39, 100, 81, 81, 44+126. Processus terminalis 2. 9 times as long as basal part of the segment. Antennal segments I–VI each with 3, 4, 14, 7, 7, 2 +3 hairs, respectively, apical part of processus terminalis with 3 hairs. Length of hairs on segment III 0.06 mm, 1.3 times as long as width diameter of the segment. Antennal segments III without obviously secondary rhinaria. Rostrum reaching abdominal segment I, ultimate rostral segment 2.5 times as long as its basal width, 2.3 times as long as second hind tarsal segment; with 4 pairs of hairs, including 1 pair of accessory hairs. Hind femur 2.2 times as long as antennal segment III, hind tibia 0.5 times as long as body. First tarsal chaetotaxy: 2, 2, 2. Siphunculi 1.0 times as long as basal diameter, 0.8 times as long as cauda, with 5 or 6 long and pointed hairs. Cauda triangular, as long as its basal diameter, with 15 hairs. Anal plate broad round, with 26 hairs.

Material examined. Holotype: apterous viviparous female, CHINA: Guangxi (Bobai County, E109.9°, N22.2°, Alt. 200m), 20 April 1981, No.Y6532-1-1, on Camellia oleifera , coll. J.D. Ma ( ZMCAS). Paratypes: 3 apterous viviparous females and 3 nymphs with the same collection data as holotype; 3 apterous viviparous females and 1 alate nymph, CHINA: Guangxi (Guilin City, E110.2°, N25.2°), 21 May 1981, No.Y6387, on Camellia oleifera , coll. X.Q. Liang ( ZMCAS); 4 apterous viviparous females and 2 nymphs, CHINA: Guangxi (Bobai County), 22 April 1981, No.Y6507, on Camellia oleifera , coll. Y.D. He ( ZMCAS, among a slide with 1 apterous viviparous female and 2 nymphs in BMNH); 4 alate viviparous females and 4 nymphs, CHINA: Guangxi (Yulin City: Liuwan High Mountain, E110.09°, N22.38°), 10 October 1981, No.Y6396, on Camellia oleifera , coll. H.Y. Wang ( ZMCAS).

Comments. As is usual with the other Toxoptera spp. , the individuals of T. chaetosiphon were colonizing new growing shoots of its host plant, and were attended by ants.

The new species has a typical stridulatory mechanism which comprises peg-like spines on the hind tibiae and roughened ventro-lateral cuticle on the posterior part of the abdomen ( Figs.12, 13, 30), this indicates inclusion in Toxoptera . Comparing with other species in the genus, the new species has some very special or unusual characters, such as numerous dorsal body hairs with tuberculoate bases and sclerotized patches at hair-bases, and siphunculi with 6-8 thick long hairs. These will be useful to recognize the new species and distinguish it from the other species with short siphunculi ( T. odinae and T.victoriae ).