Yamatochaitophorus yichunensis, Jiang, Li-Yun, Chen, Jing & Qiao, Ge-Xia, 2016

Jiang, Li-Yun, Chen, Jing & Qiao, Ge-Xia, 2016, Yamatochaitophorusyichunensis, a new species of aphid (Aphididae: Chaitophorinae) from northeast China, ZooKeys 612, pp. 41-49 : 43-48

Taxon classification Animalia Hemiptera Aphididae

Yamatochaitophorus yichunensis sp. n. Figures 1-14, 15-27, 28-30, Table 1

Specimens examined.

Holotype: apterous viviparous female, China: Heilongjiang Province, Yichun City (Tangwanghe National Forest Garden, E 129.54°, N48.45°, Alt. 360 m), 21 July 2015, No. 35896-1-1-1, on Acer tegmentosum , coll. G.X. Qiao.

Paratypes: 8 apterous viviparous females, with the same collection data as holotype (NZMC); 2 apterous viviparous females, with the same collection data as holotype (BMNH).

Etymology.

The specific name yichunensis is based on the type locality of the species.

Diagnosis.

Body small, elongate oval, adults pale yellow in life. Dorsal body covered with O- or C-like tubercles. Antenna 5-segmented, half as long as body or shorter, with processus terminalis longer than the base of last segment. Ultimate rostral segment with 1 or 2 accessory setae. Embryo with long, thick and acute spinal setae similar to marginal setae.

Description.

Apterous viviparous female: Body elongate oval, pale yellow in life (Figs 28-30). Mounted specimens. Whole dorsum pale (Fig. 15). For morphometric data see Table 1. Dorsum with longitudinal spinal ridge, and covered with “O-” or “C-” like tubercles, ventral marginal area with spinulose stripes (Figs 1, 6-9, 15, 20). Dorsal setae of body thick, long or short, flattened with knobbed or blunt apices, with well-developed tubercles at bases (Figs 1, 4-9, 20-22); ventral setae very sparse, very short and fine-pointed 1/4-1/3 of length of dorsal setae.

Head. Frons convex, antennal tubercles poorly developed (Figs 1, 16); dorsum of head with short wrinkles (Figs 1, 16). Body dorsal setae long thick, flat at apices, with well-developed tubercles at bases (Fig. 4). Head with 4-5 long thick and 2-3 short dorsal setae between antennae, and two pairs of long thick and 0-2 short dorsal setae between eyes (Figs 1, 16). Eyes with approx. 25 facets. Antennae 5-segmented (Figs 2, 18), 0.41-0.50 times as long as body; length in proportion of segments: 22-42, 18 -33, 100, 41-59, 33 –67+48– 74, respectively, processus terminalis 1.07-1.60 times as long as the base of the segment. Segments III- V weakly imbricated. Antennal setae very short and blunt, setae on inside of segments I-II short, thick and flattened at apices; segments I–V with 4, 3, 1-5, 1, 1+0 setae, respectively; apex of processus terminalis with 2-4 setae. Longest setae on segment III 0.13-0.25 times as long as basal diameter of the segment. Primary rhinaria ciliated, secondary rhinaria absent (Figs 2, 18). Rostrum (Figs 3, 19) reaching mid-coxae; ultimate rostral segment wedge-shaped, 1.57-2.00 times as long as its basal width, 0.72-0.85 times as long as second hind tarsal segment, with 1 or 2 accessory setae.

Thorax (Fig. 15). Pronotum with 1 pair of long thick anterior spinal setae, 1-3 pairs of posterior spinal setae (of which 1 pair is long and thick) and 3-5 pairs of marginal setae (of which two pairs are long and thick) (Fig. 8); mesonotum with 3-5 pairs of spino-pleural setae (of which two pairs are long and thick) and 2-5 pairs of marginal setae (of which two pairs are long and thick) (Figs 9, 22); metanotum with 4-8 spino-pleural (of which two pairs are long and thick) and 2-5 pairs of marginal setae (of which two pairs are long and thick) (Fig. 22). Legs normal. Hind femur 0.96-1.46 times as long as antennal segment III. Hind tibia 0.26-0.32 times as long as body. Setae on legs long and pointed, length of setae on hind tibiae 1.00-1.60 times as long as middle diameter of the segment. First tarsal chaetotaxy: 3, 3, 3.

Abdomen. Abdominal tergites I-VII each with one pair of spinal and one pair of marginal long thick setae with flattened or expanded apices (the expanded part is membranous) (Figs 15, 21). In addition, abdominal tergite I with 3-10 spino-pleural and 1-5 pairs of marginal shorter setae (Figs 5-6, 20); tergite II with 7-8 spino-pleural and 2-3 pairs of marginal setae; tergite III with 3-8 spino-pleural and 1-5 pairs of marginal shorter setae (Fig. 21); tergites IV-V each with 3-10 spino-pleural and 2-4 pairs of marginal shorter setae (Figs 7, 21), respectively; tergite VI with 3-10 spino-pleural and 2-4 pairs of marginal shorter setae; tergite VII with 3-6 spino-pleural and 2 -3 pairs of marginal shorter setae; tergite VIII with 6-8 setae (Fig. 15). Length of longest marginal setae on tergite I 6.60-11.00 times as long as basal diameter of antennal segment III; dorsal setae on tergite VIII 4.60-7.00 times as long as basal diameter of antennal segment III. Spiracles oval, opened or closed; spiracular plates large, oval or round. Siphunculi (Figs 10, 23) short truncated, with weak transverse imbrications, without polygonal reticulation, flanges developed, 0.67-1.33 times as long as its basal width, about 0.40-1.00 time as long as cauda. Cauda (Figs 11, 24, 26) short, rounded, slightly constricted at base, with spinulose imbrications, 0.50-0.67 times as long as basal width, with 8-14 setae, among 6 long thick setae. Anal plate (Figs 12, 25, 26) broadly rounded, with spinulose short lines; with 15-20 setae, including two long thick setae; and distal ventral area of anal plate with mosaic-like ornamentation (Fig. 26). Genital plate (Figs 13, 27) transverse oval, with spinulose transverse lines; with two pairs of anterior setae, and 9-13 posterior setae. Four gonapophyses.

Embryo (Fig. 14): Dorsal setae of body long thick and acute. Head with two pairs of frontal setae and two pairs of mid-dorsal setae. Pro-, meso- and metanotum each with a single pair of spinal setae and two pairs of marginal setae. Abdominal tergites I-VII each with one pair of spinal and one pair of marginal setae; tergite VIII with two pairs of fine and short dorsal setae. Siphunculi short, truncated. Eyes with 6-7 facets.

Host plant.

Acer tegmentosum ( Aceraceae ). The species infested the underside of leaves of the host plant, and population density was low, with less than 20 individuals dispersed on the underside of a leaf (Figs 28, 29).