Monzenia minuta Yeh, 2017

Ko, Chiun-Cheng, 2017, A new genus and two new species of galling aphids (Hemiptera: Aphididae) from Distylium (Hamamelidaceae) in Taiwan, Zootaxa 4323 (2), pp. 209-218 : 210-213

Monzenia minuta Yeh sp. n.

( Fig. 1 , 2 )

Apterous viviparous adult. (Description is based on 12 specimens). ( Fig. 1B–D ; Fig. 2A,2B ). Body oval, cuticle soft, 0.72–0.9 mm long. Head with 8–12 minute setae, without horns or dagger-like setae. Antennae 5-segmented, 100–148 µm long; last segment with 1 circular sensorium and 4 terminal setae. Eyes with 3 facets. Ultimate rostral segment pointed, about 1.20 (1.04–1.27)-times length of 2nd segment of hind tarsus. Foreleg with 1 capitate and 2 fine long setae on dorsum of 2nd tarsal segment; mid- and hindlegs each with 2 capitate and 2 fine long setae on dorsum of 2nd tarsal segment. Abdominal tergites I–V with 4–9 minute setae; abdominal tergite VIII lightly sclerotized, with 7 or 8 setae arranged in a row; abdominal tergites II–V each with a pair of spiracles which on small sclerotic plates. Siphunculi ring-like, slightly larger than spiracular plates. Cauda and anal plate not well demarcated from each other.

Alate viviparous adult. (Description is based on 27 specimens). ( Fig. 1E–H ; Fig. 2C–F ). Descriptions are based on the morphology of alate viviparous adults in the gall generation. Body length about 1.01–1.20 mm. Head width (distance between 2 apices of ocular tubercles) 0.25–0.26 mm. Antennae 5-segmented, segment III about 125–140 µm long, segment IV 60 –75 µm, segment V 35 –40 µm, total length of antennae about 1.19 (1.15–1.24)- times width of head; segment III a little broadened near basal part, with 7–9 annular secondary sensoria except on basal 1/5 or 1/7, which gradually narrows to a constricted base; segment IV with 4–6 annular secondary sensoria; segment V with 1 small circular sensorium and 4 terminal setae, with 2 or 3 annular secondary sensoria. Wings almost hyaline, broad, stigma lanceolate; media vein unbranched on forewings. Tibiae imbricate, with distinct spinules; tarsi with some spinules, 1st tarsal segments with 3-3-3 setae, 2nd tarsal segments with 3-4-4 capitate distal setae. Abdominal tergites II–V each with a pair of spiracles which on small sclerotic plates. Siphunculi slightly elevated, ring-like, slightly larger than spiracular plates. Cauda with a medial process, with many spinules at base. Anal plate bilobed, with 4–6 setae on each lobe.

Material examined. Holotype, one alate viviparous adult & one apterous viviparous adult, Yuanshan Township, Ilan Co., Taiwan, on D. racemosum , 23-ix-2006, H. T. Yeh (#505). ( The individuals of holotype are marked by circles on the slide.)

Holotype-specimen deposition: NTU, Taipei, Taiwan.

Paratype, 27 alate viviparous adults & 12 apterous viviparous adults (on 7 microscope slides), Yuanshan Township, Ilan Co. , Taiwan, on D. racemosum , 23-ix-2006, H. T. Yeh (#505)( BMNH, NMNS, NTU, TARIIC) . 4 alate viviparous adults, Yuanshan Township, Ilan Co., Taiwan, on D. racemosum , 26-ix-2009, G. S . Tung (#701)(NTU).

Etymology. The species epithet is a Latin word, ‘ minuta ’, meaning minute or small, emphasizing the small body size of the alate viviparous adult.

Remarks. This species induces closed spherical galls on twigs of D. racemosum ( Fig. 1A ). The morphologies of alate viviparous adults of M. minuta sp. n. can be distinguished from those of M. globuli (Monzen) and M. ihai Sorin as follows:

* Based on the original descriptions by Monzen (1934) for M. globuli and by Sorin (1996) for M. ihai .

Figures

FIGURE 1. Monzenia minuta sp. n. (A) induces closed spherical galls on tWigs of Distylium racemosum; (B) body, (C) head, and (D) abdomen of an apterous adult; (E) body, (F) head, (G) abdomen, and (H) Wings of an alate adult.

FIGURE 2. Monzenia minuta sp. n. (A) Head, (B) anal plate (left-upper), cauda (left-bottom) and siphunculi (right) of an apterous adult. (C) Head+antennae segments I, II, (D) antennae segments III–V, (E) Wings, (F) anal plate (upper) and cauda (bottom) of an alate adult (Scale bar=0.1 mm.)