Neuquenaphis aurata Mier Durante & von Dohlen, 2019

Nafría, Juan Manuel Nieto, Von Dohlen, Carol D., Brown, Paul A., Durante, M. Pilar Mier, Ortego, Jaime, López Ciruelos, Sara I. & Licht, Megan, 2019, Three new species of the genus Neuquenaphis (Hemiptera, Aphididae, Spicaphidinae) from southernmost South America, Zootaxa 4590 (5), pp. 525-545 : 535-538

Neuquenaphis aurata Mier Durante & von Dohlen , sp. n.

2004. Nieto Nafría, J.M., Mier Durante, M.P. and Ortego, J.: Neuquenaphis palliceps (misident.).

2010. Mier Durante, M.P., Ortego, J. and Nieto Nafría, J.M.: Neuquenaphis palliceps (misident.).

Types. Holotype: apterous viviparous female (number 16 of measurement series), CHILE, Magallanes region, Magallanes province, Fuerte Bulnes [53°37'S, 37°55'W, 100 m], 7 February 2016, on Nothofagus betuloides, Nieto Nafría, Mier Durante & Ortego leg., University of León collection . Paratypes: 68 apterous viviparous females [apt.] and 1 alate viviparous female [al.]. CHILE, Magallanes region, same data as holotype, 36 apt ; ARGENTINA, Santa Cruz province, Parque Nacional los Glaciares [50°28'S, 73°02'W, 230 m], 16 January 2000, on Nothofagus betuloides , 4 apt., 1 al., Nieto Nafría & Mier Durante leg. ; ARGENTINA, Tierra del Fuego province, Lapataia [54°51'S, 68°35'W, 20 m], 8 January 2000, on Nothofagus betuloides , 9 apt .; ARGENTINA, Tierra del Fuego province, Ushuaia [54°48'S, 68°18'W, 50 m], 7 January 2000, on Nothofagus betuloides , 19 apt. University of León and Natural History Museum London collections .

Etymology. The specific name of the new species, aurata , is a classic Latin adjective for "golden", "with the colour of gold", due to the colour in life of the apterae of the species, in the feminine gender to match the feminine Neuquenaphis genus name.

Description. Apterous viviparous females. ( Figures 3A , 4 A–I). From 69 specimens, 50 of which were measured. When alive yellow gold or yellow straw, with smoky dorsal processes. Body 2.35–3.23 mm. Other measurements are in Table 2 . Mounted specimens pale cream in general, with cephalic dorsum, antennae, clypeus, mandibular and marginal lames, rostrum and legs pale brown; siphunculi mostly also pale brown, with a small dark brown apical portion; genital and anal plates and cauda very pale brown; several finger-shaped processes also pale brown, but most of them, specially spinal and pleural ones, with distal 50-80% dark brown or very dark brown; spiracular and intersegmental sclerites inconspicuous. Tegument smooth in general. No wax pores observed. All processes with imbricated margin, with rings of wrinkles on proximal third and with spinules on middle and distal thirds, which are somewhat more robust and dense than in Neuquenaphis blackmani , and ending in sharp spines, which are shorter than the apical setae, with straight margins or lancet-shaped, but usually with blunt apices. Head with two pairs of finger-shaped processes, each of the anterior pair with two apical setae. Sometimes the seta behind each anterior process is situated upon it. Frons sinuate; a tenuous epicraneal line present. Ventral face of head with two pair of setae on an oval-medial bulge, thick and pointed, and one seta each side, delicate and pointed. Antennae longer than body and progressively pigmented to apex. Antennal segment I almost smooth and carrying 10–14 thick and pointed setae. Antennal flagellum progressively imbricate from almost smooth proximal half of segment III. Inner margin of antennal segment III with 5–16 setae, pointed and thinner than those of segment I. Base of antennal segment VI with 2(4) setae, fine and pointed. Primary sensoria ciliate and small; satellite sensoria also ciliate and most of them placed distally to primary sensorium. Rostrum short, never reaching beyond middle coxae. Ultimate rostral segment with 2–6 accessory setae, long and delicate. Prothorax with four spinal finger-shaped processes and with a postero-lateral broad rough bulge that usually carries a wart-shaped process on its anterior part, and usually with pleural and submarginal wart-shaped processes or tubercles (sometimes simple elevations). Mesothorax and metathorax with four pairs of finger-shaped processes (spinal, pleural, submarginal and marginal) on each. Legs slender. Femora smooth and with scarce setae short and pointed. Tibiae with scarce and feint striae and more abundant setae than on femora, mainly on its distal third, longer than on femora and pointed. Tarsi imbricated. Setae on first tarsal segments with 7 ventral setae and usually 2 dorsal, all long and delicate. Empodial setae spatulate. Abdominal segments 1 to 4 with 4 pairs of finger-shaped processes; abdominal segment 5 and 6 with only 3 pairs (submarginal ones lacking) on each. Siphunculus almost smooth, with 2 (sometimes one incomplete)–5 rows of cells at the apex, and with a broad flange. Abdominal segment 7 with two pairs of fingershaped processes; abdominal segment 8 with a single pair of finger-shaped processes and 1–3 in all marginal setae, delicate and pointed. Knob of cauda elongated, with 37–66 setae.

Alate viviparous females. ( Figures 3B , 4 J–Q). From 1 specimen. When alive cream yellow with head and thorax dark brown. Body 2.10 mm. Mounted specimens with head, thorax and appendages brown, with the apex of front femora dark brown, and abdomen transparent in general, with spiracular sclerites very pale, intersegmental sclerites inconspicuous, anal plate and cauda dusky, and siphunculi brown to dark brown. Tegument smooth in general. No wax pores observed. Measurements in Table 2 . Head with two short finger-shaped processes on the anterior margin, with 2 apical setae and another one on half proximal part. Frons gently wavy. Dark brown ring around each ocellus; that around the uneven one contacts the dark epicraneal line. Ventro-cephalic setae delicate and pointed, two pairs on medial oval bulge and two lateral. Antennae longer than body. Antennal segment I with 11–12 setae, similar in shape but longer than dorso-cephalic posterior setae. Antennal segment III smooth, with 15–16 setae on its inner margin, pointed and thinner than those of segment I, and with 3–4 secondary sensoria, oval-transverse, with thick margin and placed on the end of second fifth of segment length. Other antennal segments progressively imbricate. Base of antennal segment VI with 2 setae, fine and pointed. Primary and satellite sensoria ciliate. Rostrum short, not reaching beyond middle coxae. Ultimate rostral segment also short and with 4 accessory setae, long and delicate. Prothorax with two spinal setiferous elevations and a slight postero-lateral bulge. Mesothorax with two spinal short tubercles. Front leg with pigmented femorotibial articulation and different in shape to other legs, which are slender, with femur more strongly developed and with a conspicuous subapical tooth and tibia widened at base. Cuticular ornamentation and setae of legs similar to those in apterous viviparous females, except for the presence of 1–3 setae tooth-like (or spines) at the end of each tibiae. Spinal processes on all abdominal segments: rod-shaped on 1–3 and 8, tubercles on 4–6 and short rod-shaped on 7. Marginal processes on segments 1 to 6 diverse of shape: short rod-shaped or tubercles. Few and erratically disposed submarginal abdominal processes, tubercles or elevations. Apical setae of these processes always long, thin, rigid and pointed. Siphunculus as usual in alate females of Neuquenaphis , with striae on the proximal no-reticulate part, 9–10 rows of cells in the distal reticulate part and slightly flanged. Abdominal segment 8 with one lateral setae each side. Caudal knob elongated and relatively pointed, with 18 setae.

First instar nymph (or aged embryo). From 2 specimens. Antenae with 5 segments, II and VI (base) with 2 setae each. Ultimate rostral segment without accessory (secondary) setae. Processes of head inconspicuous. Other processes wart-shaped, with strong spines and minuscule apical seta, only spinal on thoracic segments, and three, two and one pairs respectively on abdominal segments 1 to 6, 7 and 8. Anal segment with 2 setae.

Karyotype. No known.

Nucleotide sequences. See above discussion of N. blackmani in addition to Figure 7 and Table 3 .

Biology. Nothofagus betuloides (Mirb.) Oerst. is the host plant of Neuquenaphis aurata sp. n. We can expect the now established species to be holocyclic, although the oviparous females and males have not been collected yet, Nothofagus betuloides is an evergreen tree.

Distribution. Neuquenaphis aurata sp. n. has been recorded in four localities, the southernmost two in the Argentine Tierra del Fuego in the northern banks of the Beagle Channel, about 580 km in a straight line from the northernmost one, situated on the shores of Argentino Lake (Santa Cruz, Argentina), marking an area that broadly coincides with that of its host plant, Nothofagus betuloides .

Taxonomic discussion, diagnostic characteristics. Neuquenaphis aurata sp. n. must be included in the nominotypical subgenus. Neuquenaphis aurata sp. n. is very similar to Neuquenaphis blackmani sp. n. Apterous viviparae of both species have a different set of dorso-prothoracic processes: N. aurata usually has a wart-shaped process on the anterior part of broad marginal bulge and pleural and submarginal wart-shaped processes. The setae on processes are also different: pointed in N. blackmani sp. n. and usually blunt in N. aurata sp. n. The quantitative characteristics of both species are very close; the only appreciable differences in apterous viviparous females are the length of the apical setae on the spinal finger-shaped processes of anterior abdominal segments (7–10 µm in N. blackmani versus 10–18 µm in N. aurata ), and the ratio length/basal width of the ultimate rostral segment (1.13–1.43 times in N. blackmani versus 0.95–1.25 times in N. aurata ). Between alata of both species the differences are: lengths of antennal segments III (absolute length and relative to processus terminalis) and IV, second segment of hind tarsi, caudal knob and apical setae on processes on abdominal segment 8 (see Table 2 ), but they have little reliability because they are based on one specimen of N. aurata . The differences of N. aurata with other species of Neuquenaphis ( N. essigi , N. edwardsi , N. schlingeri , N. valdiviana , N. palliceps , N. staryi and N. michelbacheri ) are the same as above mentioned for N. blackmani .

First instar nymphs (or aged embryos) are similar to those of N. palliceps , but cephalic and prothoracic process are finger-shaped in this species.

The original identification of the paratypes of the new species from the Argentinean provinces of Tierra del Fuego and Santa Cruz as N. palliceps ( Nieto Nafría et al., 2004; Mier Durante et al., 2010) was due to the short ultimate rostral segment, long antennae and abundant submarginal processes, which are also present in the early generations of N. palliceps .

While N. blackmani sp. n. and N. aurata sp. n. are genetically very similar (though distinct), both are well differentiated from N. palliceps , with distances ranging from 7.1–8.2% across the two loci ( Table 3 ).

The identification of apterous and alate viviparous females of N. aurata sp. n. that can be collected in the future can be done using the dichotomous key included in the taxonomic discussion of Neuquenaphis ramirezi sp. n. Ideally, future sampling would include replicate populations from both N. blackmani and N. aurata to assess intra-specific variation; from such data diagnostic nucleotide positions could be determined for each species.

Figures

FIGURE 3. Neuquenaphis aurata sp. n. A, apterous viviparous female. B, alate viviparous female.

FIGURE 4. Neuquenaphis aurata sp. n.; A–I, apterous viviparous female. A, antero-cephalic finger-shaped process. B, postero-cephalic finger-shaped process. C, D, prothoracic pleural and submarginal processes, respectively. E, prothoracic postero-lateral bulge. F, apex of antennal segment V and proximal part of antennal segment VI. G, finger-shaped process on abdominal segment 7. H, siphunculus. I, cauda. J–Q, alate viviparous female. J, anterior cephalic short finger-shaped process. K, prothoracic postero-lateral slight bulge, with seta. L, marginal short rod-shaped process on abdominal segment 3. M, submarginal tubercle on abdominal segment 3. N, spinal rod-shaped process on abdominal segment 2. O, middle portion of antennal segment III, with secondary sensoria. P, siphunculus. Q, cauda. NOTE: The scales vary according to pieces drawn; see the range of measurements in Table 2.

FIGURE 7. Neighbor-joining dendrograms for Neuquenaphis samples sequenced in this study; A, Dendrogram based on Kimura 2-parameter distances for the COI barcode locus; B, Dendrogram based on Tamura-Nei distances for the tRNA-COII locus. We were unable to obtain tRNA-COII sequences for other samples with established COI sequences. NOTE: each species name is followed by the number of the sample to which the analysed specimens belong, which begins with CHI, and in parentheses by the GenBank accession number. Sample data in legend of Table 3.