Ameroseius norvegicus Narita, Abduch & Moraes

Narita, João Paulo Z., Abduch, William Y., De Moraes, Gilberto J. & Klingen, Ingeborg, 2015, Description of a new species of Ameroseius Berlese (Acari: Ameroseiidae) from Norway, with a key to related species, Zootaxa 4034 (2), pp. 390-398 : 391-394

Ameroseius norvegicus Narita, Abduch & Moraes n. sp.

Diagnosis. Anterior margin of epistome acuminate and smooth. Corniculi bifid. Dorsal shield ornamented with ridges and pit-like depressions over most of its surface; reticulated centrally between left and right j -J and Z5 setae as well as slightly laterad of that region behind J2; with 29 pairs of setae, at least as long as distance to subsequent setae of the same series, except for j3, z5, z6 and Z3; seta j1 flat, broad and serrate, other dorsal idiosomal setae stout and weakly serrate. Setae st3 on separate platelets. Opisthogaster with five pairs of setae, all on soft cuticle, in addition to circumanal setae.

Adult female ( Figs. 1–10 ) (4 specimens measured)

Gnathosoma: Cheliceral shaft length (from base of first segment to apex of fixed cheliceral digit) 98 (97–100) long; dorsal and lateral lyrifissures distinct; dorsal seta indistinct; fixed cheliceral digit 23 (22–24) long, with three large teeth along the internal edge and a minute subapical tooth, in addition to apical tooth; movable cheliceral digit 24 (23–25) long, only with apical tooth; internal surface with a wavy longitudinal line that is more easily discernible near level of the large teeth of fixed digit; the line apparently corresponds to the limit between the thicker ventral and the thinner dorsal regions of the digit ( Fig. 1 ). Anterior margin of epistome acuminate, smooth, with a row of denticles parallel to the margin ( Fig. 2 ). Corniculi bifid. Deutosternum relatively broad, 6.5 (6–7) wide at median level; with eight transverse lines, of which the most distal and the two most proximal lines smooth; other lines with 1-2 denticles each; with a pair of diagonal rows of denticles behind sc, converging posteriorly to merge with the lateral margins of deutosternum ( Fig. 3 ). Hypostomal and subcoxal setae aciculate; their length: h1 18 (17-20), h2 22 (20-25), h3 21 (19-23), sc 26 (24-28). Palpus 94 (93–96) long; numbers of setae from trochanter to tibia: 2, 5, 6, 14. Palp apotele trifid.

Dorsal idiosoma: Dorsal shield entire ( Fig. 4 ), ornamented with ridges and pit-like depressions over most of its surface; reticulated centrally between right and left j -J and Z5 setae as well as slightly laterad of that region, behind J2 ( Fig. 5 ); with a row of teeth along anterior margin, between j1 and s1; 500 (468–513) long and 332 (312– 357) wide at level of s6; apparently with three pairs of pores (laterad of z6, anterolaterad of Z3 and anteromediad of S5). Podonotal region of dorsal shield bearing 19 pairs of setae (j1–j6, z2, z4–z6, s1, s2, s4–s6, r2–r5); opisthonotal region of dorsal shield bearing ten pairs of setae (J2, J4, Z1–Z3, Z5, S2–S5). Lengths of dorsal

setae: j1 33 (28–35), j2 39 (36–42), j3 49 (47–52), j4 62 (58–65), j5 93 (89–96), j6 100 (98–105), J2 101 (97–104), J4 113 (108–115), z2 55 (50–60), z4 58 (56–62), z5 38 (36–41), z6 36 (34–37), Z1 50 (47–55), Z2 55 (54–57), Z3 40 (37–43), Z5 117 (115–121), s1 53 (49–56), s2 59 (56–63), s4 70 (67–74), s5 70 (67–76), s6 68 (60–73), S2 71 (66–73), S3 99 (95–104), S4 97 (95–99), S5 115 (112–117), r2 73 (67–75), r3 60 (58–64), r4 50 (47–54), r5 53 (49–56). Dorsal shield setae at least as long as distance to subsequent setae of the same series, except for j3, z5, z6 and Z3; seta j1 flat, broad and serrate ( Fig. 6 ); other dorsal idiosomal setae stout and weakly serrate ( Fig. 7 ).

Ventral idiosoma ( Fig. 8 ): Base of tritosternum 12 (11–13) long and 10 (10–13) wide, laciniae fused for about 40% of their total length [58 (57–60)]. Sternal shield reticulate with simple lines, 80 (76–83) long at midline and 115 (112–120) wide at the widest level, with lateral projections between coxae I and II, bearing st1 and st2 as well as two pairs of lyrifissures. Seta st3 on separate platelets. Seta st4 and lyrifissure iv3 on unsclerotised cuticle. Genital shield reticulate with simple lines, 128 (123–133) long including hyaline anterior flap, bearing st5; width at base of hyaline flap 63 (61–66), at level of st5 68 (66–70); posterior margin rounded. With a pair of pores (gv2, according to interpretation of Narita et al. 2013a) on unsclerotised cuticle laterad of st5 and a pair of lyrifissures (iv5) posteromesad of gv2. One pair of metapodal plates of variable shape (usually ellipsoidal). Anal shield oval, with longer axis transverse, about 110 (100–120) long and 169 (160–175) wide, bearing only circumanal setae; anal opening 36 (35–37 including frame) long. Unsclerotised cuticle around anal shield with five pairs of setae (Jv1–Jv3, Jv5, Zv2) and five pairs of lyrifissures (posterolaterad of Jv1, laterad of Jv3, anterolaterad of Jv5, posterolaterad of Jv5 and posterior to metapodal plates). Lengths of ventral setae: st1 33 (30-40), st2 32 (30-36), st3 38 (35-40), st4 26 (25-27), st5 22 (20-24), Jv1 19 (18-22), Jv2 16 (15-17), Jv3 18 (16-21), Jv5 24 (23-27), Zv2 16 (14-20), para-anal 24 (23-25), post-anal 24 (23-25). Endopodal plate fragmented, fused to sternal shield between coxae I and II, a boomerang-shaped platelet between coxae II and III and a subtriangular platelet between coxae III and IV. Exopodal plate represented by a remnant triangular platelet between coxae I and II.

Peritreme and peritrematic shield: Peritreme reaching level of j1, not visible dorsally. Peritrematic shield broad; fused with dorsal shield at level of j2; with a large pore at level of coxa III (gd3 of Athias-Henriot, 1975; gp2 of Lindquist & Moraza, 2009), with a lyrifissure behind stigma.

Spermathecal apparatus ( Fig. 9 ): Induction pore not discernible; tubuli reaching sacculus separately but close to each other; each with an enlargement before sacculus, apparently the ramus ( Evans, 1992), called intermediate piece (pièce intermediaire) by Elsen (1973).

Legs: Pretarsi of legs I–IV consisting of an elongate stalk, a pair of claws and pulvillus with three rounded lobes ( Fig. 10 ). Lengths of legs: I—449 (415–480); II—356 (350–365); III—359 (340–385); IV—446 (415–465). Chaetotaxy of legs I–IV: coxae: 2, 2, 2, 1; trochanters: 6, 5, 5, 5; femora: 12 (2 3/1 2/2 2), 10 (2 2/1 2/2 1), 6 (2 2/0 1/0 1), 5 (1 2/0 1/0 1); genua: 11 (1 3/1 2/2 2), 11 (2 3/1 2/1 2), 9 (2 2/1 2/0 2), 9 (2 2/1 3/0 1); tibiae: 12 (2 2/1 3/2 2), 10 (2 2/1 2/1 2), 8 (1 2/1 1/1 2), 9 (2 2/1 2/1 1); tarsi II–IV: not counted, 17, 17, 17. All dorsal setae of femora, genua and tibiae, anterolateral setae of femur II, genua II and IV, and tibiae II and IV, posterolateral setae of femora I and II, genua I–IV and tibiae I–III stout and weakly serrate; other leg setae setiform and smooth. With the following numbers of transverse or diagonal lines of denticles on the ventral side of legs I–IV: coxa, 0–2; trochanter, 0–3; femur, 1–2; genu, 1–3; tibia, 1–3; venter of distal rim of these segments also denticulate.

Adult male: unknown.

Material examined. All specimens collected from litter from a strawberry field at Sylling (5954'00"N and 1016'54"E; altitude: 170 m), Buskerud county, Norway, by Dr. I. Klingen and her collaborators. Holotype female and eight paratype females collected in April 14, 2011; twelve paratype females collected in April 27, 2011. Holotype and paratypes are deposited at Departamento de Entomologia e Acarologia, Escola Superior de Agricultura “Luiz de Queiroz, Universidade de São Paulo, Piracicaba, State of São Paulo, Brazil.

Etymology. The specific name norvegicus refers to “from Norway ”, referring to the country from which the type specimens were collected.

Remarks. This new species is most similar to Ameroseius ulmi Hirschmann , in Westerboer & Bernhard (1963). However adult females of A. norvegicus have seta j1 flat and broad (j1 leaf-shaped in A. ulmi ); dorsal shield setae in general longer, reaching the base of the subsequent setae in the series, except j3, z5, z6 and Z3 (only j1, Z2 and r2 reaching the base of the subsequent seta in the series in A. ulmi ).

Spermathecae of nine Ameroseius species have been described, all by Elsen (1973), who mentioned variations between species to refer mostly to the type of insertion of the tubuli into the sacculus (separate but close together, well separated, both inserted into a common ramus), as well as the shape of the induction pore and ramus. The shape of the rami and the distance between the insertions of the rami into the saculus in A. norvegicus n. sp. are most similar to Ameroseius benoiti Elsen , but the rami of the latter species are more elongate and its distal half is narrower than its proximal half (referred to as inverted bottle-shaped by Elsen, 1973).

Figures

FIGURES 1 – 8. Ameroseius norvegicus Narita, Abduch & Moraes n. sp. female. 1. Antiaxial view of chelicera; 2. Epistome; 3. Ventral view of gnathosoma; 4. Dorsum of idiosoma; 5. Dorsal shield ornamentation (a: pit-like depression; b: ridge; c: reticulated area); 6. Detail of seta j 1; 7. Detail of seta j 4; 8. Venter of idiosoma. Pores and lyrifissures enlarged to allow their differentiation.

FIGURES 9 – 16. Ameroseius spp. 9. Ameroseius norvegicus, female. 9. Spermathecal apparatus; structure in broken line next to, but of unknown relation with spernathecal apparatus; 10. Ameroseius norvegicus, female, Pre-tarsus of leg I. 11 – 16. Modified from Elsen (1973) to show the spermathecal apparatus of some Ameroseius species. 11. A. mirus; 12. A. benoiti; 13. A. gillardinae; 14. A. leclercqi; 15. A. gabonensis; 16. A. bembix.