Allocotaphis Börner, 1950

Stekolshchikov, Andrey V. & Qiao, Ge-Xia, 2023, Revision of the genus Allocotaphis Börner, 1950 (Hemiptera, Homoptera, Aphididae, Macrosiphini), Zootaxa 5227 (1), pp. 63-99 : 65-66

Genus Allocotaphis Börner, 1950

Publication reference: B̂rner, C. (1950) Neue europäische Blattlausarten. Naumburg, privately published: 4.

Malaphis Shaposhnikov, 1951: 517

Malachis Grigorov, 1980: 49 , double misprint for Malaphis Shap [oshnikov]

Spinaphis L.K. Ghosh, 1986: 125 , syn. n.

Longisiphoniella Chakrabarti, Saha & Mandal, 1988: 36 , syn. n.

Type species: Neanuraphis quaestionis B̂rner, 1942, by original designation.

Etymology. The generic name Allocotaphis is of feminine gender and derived from Greek word “ allokot (os)” (“αλλόκοτος”) meaning “nondescript, of unusual nature” and the new Latin word “ aphis ” (“plant-louse”) ( Cortés Gabaudan et al. 2011)

Description. Body ranging from elongate to broadly elliptical or almost rounded (fundatrices). Fundatrices mostly membranous; apterous females from the secondary host, alate emigrants and gynoparae strongly sclerotized, often with a single shield on the tergum; alatae also with paired sclerotized maculae located on abdominal sternites IV–VII; alate males with sclerotized bands and sclerites of different sizes on abdominal tergites; oviparous females mostly membranous ( A. quaestionis ) or with sclerotized bands and sclerites on abdominal tergites ( A. minensis ). Setae on body and appendages pointed, finely pointed, blunt or sometimes weakly capitate. Marginal tubercles present only on prothorax of alate morphs including males, occasionally only one side or absent; they are small, often sclerotized, conical, weakly protuberant, or flat. Spinal tubercles absent. Epicranial suture complete or reduced in fundatrices, reduced or absent in other morphs. Antennal tubercles in all morphs divergent, conspicuous but not high; medial tubercle low or very low, often inconspicuous. Antennae 5- or 6-segmented, secondary rhinaria present on antennal segments III–V in alate morphs and sometimes in apterous viviparae from secondary host; primary rhinaria non-ciliated; secondary rhinaria elliptical or rounded, strongly protuberant, with a domed swollen membrane; many rhinaria resemble the teeth of a ripsaw—the distal edge of the sclerotized base of each rhinarium is lower than its proximal edge, so that the central axis and apex of the rhinarium is tilted toward the apex of the segment. Chaetotaxy of first tarsal segments of all morphs 3, 3, 2, rarely 3, 3, 3, except in fundatrices (2, 2, 2) and sometimes in oviparae (from 2, 2, 2 to 3, 3, 2). Arms of mesosternal furca of fundatrices and oviparous females separated, those of apterous viviparae from secondary host connected by wide base. Spiracles rounded, faintly reniform, almost elliptical. Siphunculi mostly cylindrical, tapering towards apex, with a well-developed flange; those of fundatrices and oviparous females elongated-conical; surface of siphunculi more or less smooth, covered with very thin and wide scales formed by partially fused strongly smoothed or pointed spinules. Subgenital plate oval. Cauda escutcheon-shaped, sometimes almost semicircular.

Taxonomic relationships. An analysis of morphological similarities between genera Allocotaphis B̂rner, 1950, Spinaphis L.K. Ghosh, 1986 and Longisiphoniella Chakrabarti, Saha & Mandal, 1988 shows that Spinaphis L.K. Ghosh, 1986 syn. n. and Longisiphoniella Chakrabarti, Saha & Mandal, 1988 syn. n. should be considered as subjective synonyms of the genus Allocotaphis B̂rner, 1950.

Allocotaphis is close to the two other genera associated with the host-plant tribe Maleae : Sorbaphis Shaposhnikov, 1950 and Muscaphis B̂rner, 1933. The three undoubtedly constitute a closely related group characterized by a short, escutcheon-shaped cauda, an almost complete absence of marginal and spinal tubercles, non-ciliated primary rhinaria, and occasionally setae on the siphunculi. Muscaphis differs from Allocotaphis and Sorbaphis in the shape of the secondary rhinaria: they are flattened to slightly convex, whereas in Allocotaphis and Sorbaphis they are situated on strongly protruding sclerotized bases, resembling the teeth of a ripsaw. In addition, apterous viviparous females from the secondary host, gynoparae, males and oviparous females of Muscaphis differ from Allocotaphis and Sorbaphis in the form of their siphunculi with a rounded apex, lacking a flange, and an opening shifted to the opposite side of the body; siphunculi of Allocotaphis and Sorbaphis are cylindrical, tapering towards the apex, and with a distinct flange. Spiracles of Allocotaphis and Sorbaphis are rounded, faintly reniform, almost elliptical; those of Muscaphis are more or less covered with convex plates formed by peritremes. The species of the genus Allocotaphis are most similar to the only species of the genus Sorbaphis , S. chaetosiphon Shaposhnikov, 1950 , from which they differ in the smooth cuticle with sparse spinules on the dorsal side of the body (the cuticle in S. chaetosiphon is more or less reticulate, which is especially pronounced in apterous viviparous females from the secondary host), the absence of setae on the siphunculi (single seta can be found only in A. minensis , while the setae on the siphunculi are always present in S. chaetosiphon ), and a smaller number of setae on the first segments of fore and middle tarsi; alate morphs of Allocotaphis , including males, apterous viviparous females from the secondary host, and often oviparous females have 3, 3, 2 tarsal setae, whereas Sorbaphis have 4, 4, 2.