Macrosiphoniella (Macrosiphoniella) nikolajevi Kadyrbekov, 1999

Stekolshchikov, Andrey V. & Buga, Sergey V., 2022, Revision of the aphid subgenus Ramitrichophorus Hille Ris Lambers of genus Macrosiphoniella (Hemiptera, Homoptera: Aphididae, Macrosiphini), with redescriptions of all known species and identification keys, Zootaxa 5183 (1), pp. 293-342 : 332-334

Macrosiphoniella (Macrosiphoniella) nikolajevi Kadyrbekov, 1999

( Figs. 64–70 , Tabl. 6 )

Material. Paratype: 5 apterous viviparous female, „ Macrosiphoniella nikolajevi sp. n., Helichrysum maracandicum , W. Kazakhstan, Kyrgyz Ridge , Makpal gorge, H—1500, 20.vii.1996, Nikolaev G. V.” (from the collection of ZIN RAS) .

Etymology. The species was named in honor of the famous Soviet Kazakh entomologist Georgiy Vladimirovich Nikolaev, who first collected this species.

Systematic position. Kadyrbekov reffered Macrosiphoniella nikolajevi to the subgenus Ramitrichophorus on the basis of the shape and length of the ultimate rostral segment, as well as the belonging of its host plant to the genus Helichrysum , with which all other species of this subgenus are associated. At the same time, he pointed out that the new species sharply differs from all species known in this subgenus by the large number of secondary rhinaria on the third antennal segment, their absence on the fourth segment of apterous viviparous females, the type of dorsal sclerotization, the shape of the cauda, very long and thick setae on the body, antennae and legs ( Kadyrbekov 1999). Later, he began to consider the species as part of the nominative subgenus without explaining the change in its taxonomic status ( Kadyrbekov 2017). The complete absence of rhinaria on the fourth segment of the antennae is typical for most individuals of the species of the subgenus, and M. (R.) medvedevi has long and numerous setae, but the rest of the listed characters really clearly distinguish nikolajevi from other species of Ramitrichophorus . This is especially evident in the example of the shape of the cauda—triangular, acute and with a small number of setae in all species of Ramitrichophorus (one of the characters on the basis of which Hille Ris Lambers (1947) actually distinguished the subgenus) and typical for most other Macrosiphoniella elongate fingershaped, with constriction in the basal half and often with numerous setae (as in nikolajevi ). The setae on the ultimate rostral segment of nikolajevi , like in most Macrosiphoniella , are long, while the setae located closer to the base of the segment are significantly longer than the setae on the apex of the segment, which also distinguishes it from all species of Ramitrichophorus in which all setae on the last segment of the rostrum are short and of approximately equal length. In addition, the species differs from all species of Ramitrichophorus in the shape of the ultimate rostral segment—in Ramitrichophorus species it is "nail-like" (with a slight extension at the base, then with almost parallel edges and pointed at the apex), while in nikolajevi , the ultimate rostral segment is elongated wedge-shaped, more or less gradually tapering towards apex typical enough for most Macrosiphoniella . Thus, the morphological similarity between other species of Ramitrichophorus in nikolajevi is practically limited only by the long length of the ultimate rostral segment, which may be explained rather by convergence associated with the similarity of the host plant rather by phylogenetic relationship.

Distribution. Kazakhstan (Jambyl Region and Turkistan Region) ( Kadyrbekov 1999, 2002, 2017), Iran (Tehran Province, Alborz Province, Isfahan Province) ( Kanturski & Barjadze 2018; Momeni Shahraki et al. 2019).

Biology. Lives on the stem and under the flowers of Helichrysum maracandicum Popov in scattered colonies.

Figures

FIGURE 64. Apterous viviparous female of Macrosiphoniella (Macrosiphoniella) nikolajevi Kadyrbekov, 1999 (Paratype).

FIGURES 65–70. Macrosiphoniella (Macrosiphoniella) nikolajevi Kadyrbekov, 1999, apterous viviparous female. 65, 3rd antennal segment; 66, head; 67, ultimate rostral segment; 68, hind tarsus; 69, siphunculus; 70, cauda.