Mollitrichosiphum (Metatrichosiphon) nigrum, Zhang, Dong & Qiao, Gexia, 2010

Zhang, Dong & Qiao, Gexia, 2010, Mollitrichosiphum Suenaga from China (Hemiptera: Aphididae), with the description of one new species, Zootaxa 2608, pp. 1-24: 12-15

publication ID

http://doi.org/ 10.5281/zenodo.197753

DOI

http://doi.org/10.5281/zenodo.5614791

persistent identifier

http://treatment.plazi.org/id/03F187F8-0954-3A6E-FF09-DE1BFB582382

treatment provided by

Plazi

scientific name

Mollitrichosiphum (Metatrichosiphon) nigrum
status

sp. nov.

Mollitrichosiphum (Metatrichosiphon) nigrum   sp. nov.

( Figures 6 View FIGURE 6 , 13 View FIGURE 13 c, d)

Description. Apterous viviparous female: Body black with thin white pruinosity in life. For general measurements see Table 1 View TABLE 1 . Mounted specimens: body oblong oval ( Figs. 6 View FIGURE 6 o, 13 c).

Mounted specimens: Head: Dorsum of head, antennal segments I–II, and ultimate rostral segment dark brown, antennal segments III–VI brownish. Head fused with prothorax. Antennal segments III–VI with transverse imbrications, head with ventral spinulose imbrications on the lateral sides. Median portion of front flat, antennal tubercles slightly developed ( Fig. 6 View FIGURE 6 a). Dorsal setae thick and long, mostly acuminate, rarely furcate; ventral setae fine, long and pointed. Head with two pairs of frontal setae, three pairs of dorsal setae between antennae, and three or four pairs of dorsal setae between eyes. Eyes multi-faceted, with ocular tubercles. Antennae six-segmented ( Figs. 6 View FIGURE 6 b, 6 c), proportion of segments I–VI: 20, 14, 100, 31, 38, 31+ 45, respectively. Antennal setae pointed at apex, setae directed outwards distinctly longer than setae pointing inwards, segments I–VI each with 7 –9, 5–7, 27–35, 5 or 6, 4 or 5, 3+ 4 setae, respectively; apex of processus terminalis with three short setae. Rostrum reaching abdominal segment I; ultimate rostral segment long wedge-shaped ( Fig. 6 View FIGURE 6 d), with 3 pairs of primary setae and 6-7 pairs of secondary setae.

Thorax: dorsum of thorax brown. Venter with spinulose imbrications. Dorsal setae of thorax thick and long, pointed or furcate. Pronotum with 22–24 setae; mesonotum with 24–26 setae; metanotum with 28–30 setae. Mesosternal furca blackish brown, sclerotized distinctly, with a short stem ( Fig. 4 View FIGURE 4 ), length of single arm 0.11–0.15 mm, 2.69–3.68 basal diameter of antennal segment III. Femora and tibiae brownish, tarsi brown. Hind tibiae with 53–63 transverse ridges in basal 3 / 4, tarsi with weakly transverse imbrications. First tarsal chaetotaxy: 7, 7, 7.

Abdomen: brown, except siphunculi dark brown. Venter of abdominal segments I–VI with coarsely spinules. Dorsal setae of abdomen thick and long, pointed or furcate, ventral setae fine and pointed, dorsal setae 1.89–3.19 times as long as ventral setae. Abdominal tergites I–VI with 18 –24, 32–38, 40–44, 44–48, 30– 34, 16– 18 setae, respectively; tergite VII with two pairs of spinal setae; tergite VIII with one pair of spinal setae. Spiracles on prothorax and abdominal segments I–VII round, and open. Siphunculi extremely long, slightly swollen in median ( Fig. 6 View FIGURE 6 h), flange distinct, densely spinulose imbrications in apical, other parts with spinules; with 110–130 long setae. Cauda and anal plate spinulose. Cauda semi-round ( Fig. 6 View FIGURE 6 i), with 8–10 thick and long setae. Anal plate transversely elliptical, with 16–22 thick and long setae and a transverse band of cell-like markings in apical ( Fig. 6 View FIGURE 6 j). Genital plate transverse oval ( Fig. 6 View FIGURE 6 k), with 14–18 setae and spinulose imbrications. Gonapophyses three, each with two or three short and pointed setae.

Alate viviparous female: Body 1.71–2.68 mm long, 0.74–1.06 mm wide. General measurements see Table 2 View TABLE 2 .

Mounted specimens: Body oblong oval ( Figs. 6 View FIGURE 6 p, 13 d). Head: Dorsum of head, antennal segments I to III and rostral segment V dark brown, antennal segments IV to VI and rostral segment IV brownish. Head separated from prothorax. Antennal segments IV to VI with transverse imbrications. Head with 15–17 dorsal setae. Antennae six-segmented. Length in proportion of antennal segments I–VI: 16: 12: 100: 31: 39: 31 + 48, respectively. Antennal setae stout and long, pointed at apex, segments I–VI each with 5 –7, 4 or 5, 21–25, 7–9, 5, 4 + 4 setae, respectively; apex of processus terminalis with four short setae. Antennal segment III with 14–16 round secondary rhinaria; primary rhinaria round and weakly ciliated. Rostrum reaching hind coxa, with 3 pairs of primary setae and 7 pairs of secondary setae.

Thorax: Dorsum of thorax dark brown. Dorsal setae of thorax long and pointed. Pronotum with 20–24 dorsal setae. Femora, basal and apical tibiae, and tarsi dark brown, median part of tibiae brownish. Femora with sparse spinules in distal part on inner surface, tarsi with weakly transverse imbrications. Hind tibia with 49–53 short transverse ridges in basal 3 / 5. Veins of wings and pterostigma dark brown. In fore wings media twice branched; pterostigma long wedge shaped; hind wings with 2 oblique veins.

Abdomen: From the median part of tergites III to VI fused each other, forming a large sclerotized brown patches; marginal part brownish; siphunculi, cauda, anal plate and genital plate dark brown. Venter of abdominal segments III–V with coarsely spinules. Abdominal tergite I with 10 setae, tergite VII with 4 setae, tergite VIII with 2 setae. Spiracles on prothorax and abdominal segments I–VII oval and open, spiracular sclerite oval and brown. Siphunculi extremely long ( Fig. 6 View FIGURE 6 p), flange distinct, with spinulose imbrications in basal and distal part, other parts with imbrications; 21.23–23.16 times as long as its distal width; with 189– 210 long and short setae. Cauda sub-triangle with spinules, and 8–10 thick and long setae. Anal plate transversely elliptical with spinules, with 15–17 thick and long setae. Genital plate transverse oval, with spinulose imbrications, with 18–22 setae. Others same as apterous viviparous female.

First-instar nymph: Body long oval ( Fig. 6 View FIGURE 6 m).

Mounted specimens: Head fused with prothorax. Median front slightly convex, antennal tubercles indistinct. Eyes with eight facets and ocular tubercles. Antennae four-segmented, about 0.50 times as long as body length, segments III and IV with transverse imbrications; length in proportion of segments I–IV: 37: 28: 100: 52 + 69, respectively; processus terminalis about 1.33 times as long as base of segment IV; segments I–IV each with 0 or 1, 2, 1 or 2, 2+0 stout and long setae, respectively; apex of processus terminalis with two or three setae; length of setae on segment III about 2.33 times as long as widest diameter of the segment. Rostrum reaching abdominal segment VI; ultimate rostral segment slender and long wedge-shaped, 5.76 basal width, 2.14 second hind tarsal segment. Dorsal setae thick and long, pointed. Head with one pair of frontal setae, two pairs of spinal dorsal setae, and two pairs of lateral setae. Pronotum with one pair of spinal setae and one pair of long and stout lateral setae; mesonotum and metanotum each with one pair of spinal setae, and two pairs of pleural setae. Abdominal tergites I–V each with one pair of spinal, one pair of pleural, and one pair of marginal setae; tergite VI with one pair of pleural setae; tergite VII with one pair of spinal setae and one pair of marginal tubercles, each with one stout hair at apex; tergite VIII with one pair of spinal tubercles, each with one stout hair at apex. First tarsal chaetotaxy: 2, 2, 2. Siphunculi bare, cone-shaped, about 0.14 times as long as body. Cauda and anal plate each with 4 thick and long setae.

Material examined. Holotype, apterous viviparous female, China, Guangxi: Longsheng, 21.v. 2006, No. 18913, on Meliosma cuneifolia (J.F Wang)   .

Paratypes: 3 apterous viviparous females and 2 alate viviparous females, data same as holotype; Guangxi: Xing’an: Yong’ancun, 2.vii. 2006, No. 19258, 5 apterous viviparous females and 1 alate viviparous female on Ailanthus altissima (J.H. Huang)   ; China, Fujian: Mt. Wuyi, alt. 820m, 6.vii. 2003, No. 14417, 2 apterous viviparous females, 1 alate viviparous female and 2 apterous viviparous nymphs on Elaeagnus pungens (X.L. Huang)   ; Jianyang, 2.vii. 1973, No. 5265, 2 apterous viviparous females, 4 alate viviparous females, 1 apterous viviparous nymph and 4 alate viviparous nymphs on Meliosma myriantha (C.L. Fang & B.L. Zhang)   .

Distribution. China (Fujian, Guangxi).

Host plants. Ailanthus altissima   ( Simaroubaceae   ), Meliosma cuneifolia   , Meliosma myriantha   ( Sabiaceae   ) and Elaeagnus pungens   ( Elaeagnaceae   ).

Etymology. The new species is named for its body color in life. “ nigrum   ” (Latin) means black, dark. Comments. This new species can be easily separated from other congeneric species by black body with slightly wax powders in life. The new one is similar with Mollitrichosiphum rhusae   , but differed from it in: more transverse ridges on hind tibia, with 53–63 in apterae, 49–53 in alatae ( rhusae   : 27–46 in apterae, 40–43 in alatae); in alatae: secondary rhinaria on antennal segment III fewer, with 14–16 ( rhusae   : 20).