1✉ Universidade Federal Rural de Pernambuco – UFRPE, Área de Fitossanidade, 52171-900, Recife, PE, Brazil.
2Universidade Estadual de Santa Cruz – UESC, Departamento de Ciências Biológicas, 45662-900, Ilhéus, BA, Brazil.
3Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo – ESALQ/USP, Departamento de Entomologia e Acarologia, 13418-900, Piracicaba, SP, Brazil.
4Universidade Federal Rural de Pernambuco – UFRPE, Área de Fitossanidade, 52171-900, Recife, PE, Brazil.
2023 - Volume: 63 Issue: 2 pages: 522-528
https://doi.org/10.24349/ayvq-7aciThe Atlantic Forest is a Brazilian biome located mainly along the eastern part of the country's coast between the states of Rio Grande do Norte (in the northeast) and Rio Grande do Sul (in the south). Despite the drastic reduction of the preserved area since the Brazilian colonization in the 16th century, this biome is considered one of the main global biodiversity hotspots (Myers et al. 2000; Tabarelli et al. 2010). In recent years, studies conducted in this ecosystem have demonstrated a high diversity of phytoseiid mites, with discoveries of new species and genera (Castro and Moraes 2010; Ferla et al. 2012; Mineiro et al. 2012; Gonçalves et al. 2013, 2015; Moraes et al. 2013; Rocha et al. 2013, 2014; Barbosa et al. 2014; Nuvoloni et al. 2015; Lofego et al. 2016). Mites of this family have been extensively studied worldwide for their importance as biological control agents of pest organisms (McMurtry et al. 2015).
The only species of Serraseius Moraes, Barbosa & Castro (Phytoseiidae), described from the Atlantic Forest, led to characterization of the genus as having 17 pairs of serrate and relatively long setae on the dorsal idiosoma; light sclerotization of the sternal shield, with indistinct anterior and posterior margins; fixed cheliceral digit with few teeth; absence of J2, S2 and leg macrosetae; females without setae JV3 and ZV3; and reduced ventrianal shield, bearing a single pair of pre-anal setae (JV2) (Moraes et al. 2013).
The objective of this paper is to describe the second species of the genus, based on females collected in a fragment of the Atlantic Forest in northeastern Brazil, and to adjust the generic characterization, based on features of the new species.
Towards the end of 2022, the mites considered in this study were collected from a fragment of approximately 1.157 ha that has been included as part of the Atlantic Forest Biosphere Reserve, established by the Pernambuco state government for preservation purposes (SEMAS 2022). According to the Köppen-Geiger classification system, the local climate is classified as tropical Monsoon (Am) (Beck et al. 2018), with monthly average temperature of 26 ºC and annually average rainfall of 2.263 mm. The vegetation is classified as Dense Ombrophiles Forest, with canopies commonly reaching 20–30 m in height.
Extracted leaf samples were examined under a stereomicroscope in the laboratory, collecting the phytoseiid mites and mounting them in Hoyer's medium. These were later examined under a phase-contrast microscope (Olympus® BX41), and determined to belong to an unknown species of Serraseius, which is described herein. Illustrations were made using Adobe Illustrator® software, based on images captured with a Moticam Pro 285B digital camera. Measurements of taxonomic relevant structures were made using a graded eyepiece, and are shown in micrometers, with those of the holotype shown in bold and followed by the mean, minimum and maximum (in parentheses) of all specimens examined. The photographs were captured with a digital camera Nikon DS-L3 under the optics of a Nikon Eclipse Ni-U interference phase microscope.
The nomenclature of the dorsal idiosomal setae is that of Lindquist and Evans (1965), adapted by Rowell et al. (1978) for the phytoseiids; nomenclature of the ventral setae follows Chant and Yoshida-Shaul (1991). Pore and lyrifissure nomenclature is that of Athias-Henriot (1975). The proposed idiosomal setal pattern follows Chant and Yoshida-Shaul (1992).
ZOOBANK: 71330D9A-8CAD-49E1-9B2D-3BC3FE7905D1
(Figures 1–2)
All 17 pairs of dorsal idiosomal setae as well as JV5 serrated; ventral setae smooth. Dorsal shield reduced, surrounded by a wide marginal band of unsclerotized cuticle; anterolaterally reticulate, up to the insertion of S2; smooth posteriad S4-Z4 and of irregular ornamentation, including the presence of short arches, elsewhere; with distinct constriction at level of R1; seta S5 inserted on unsclerotized cuticle next to dorsal shield. Dorsal setae longer than 20 μm, except j1, J5 and S5. Peritreme extending to level of j1. In microscopic preparations, JV5 is always on the posterodorsal region of idiosoma. Dorsal shield with four pairs of pores (gd1, gd2, gd5, gd9). Sternal shield smooth, lightly sclerotized, with three pairs of setae (st1–st3) and with region anteriad iv1 (where st1 is inserted) even less sclerotized; posterior margin with irregular incisions. With five pairs of opisthogastric setae on unsclerotized cuticle (JV1, JV4, JV5, ZV1, ZV2). Ventrianal shield reduced, ovoid, about 1.5 times as long as its largest width, smooth, with only one pair of pre-anal setae (JV2); pre-anal pores (gv3) rounded and close together. Spermathecal calyx trumpet-shaped; atrium bulbous, c-shaped. Fixed cheliceral digit with a single tooth in addition to the apical tooth; pilus dentilis stout but discreet; movable digit with two teeth. Leg genu II with 8, III with 7 and IV with 7 setae; macrosetae absent in all legs.
Idiosoma — (Figs. 1A, 2A) 329 331 (306–341) long and 168 168 (171–225) wide at level of s4. With 17 pairs of dorsal setae (j1, j3–j6, J5, z2, z4, z5, Z4, Z5, s4, S2, S4, S5, r3, R1) and 11 pairs of ventral setae (st1–st5, JV1, JV2, JV4, JV5, ZV1, ZV2) in addition to circumanal setae. All dorsal idiosomal setae and JV5 serrate; ventral setae smooth.
Dorsal idiosoma — (Figs. 1A, 2A). Dorsal shield reduced, surrounded by a wide margin of unsclerotized cuticle; anterolaterally reticulate up to the insertion of S2; smooth posteriad S4-Z4 and irregularly ornamented, including the presence of short arches, elsewhere; with distinct constriction at level of R1; seta S5 inserted on unsclerotized cuticle, next to dorsal shield; with seven pairs of visible lyrifissures (id1, id2, idl1, idl3, idl4, idm4, idm6) and four pairs of pores (gd1, gd2, gd5, gd9); 254 252 (247–254) long and 114 123 (114–128) wide at the level of s4. Lengths of setae: j1 15 15 (12–15), j3 25 26 (25–27), j4 22 23 (22–25), j5 25 24 (22–25), j6 42 42 (40–44), J5 10 8 (7–10), z2 40 41 (40–44), z4 27 28 (27–30), z5 22 24 (22–25), Z4 37 38 (35–40), Z5 57 57 (52–59), s4 47 45 (42–47), S2 44 45 (42–49), S4 37 38 (37–42), S5 17 16 (12–17), r3 37 37 (35–42) and R1 27 30 (27–33). Unsclerotized cuticle posterolaterad dorsal shield with three pairs of lyrifissures (ip, which usually occupies a posteroventral position on the idiosoma in other phytoseiids, Rp and an unidentified lyrifissure). Peritreme extending to level of j1.
Ventral idiosoma — (Figs. 1B, 2B-C). Sternal shield longer than wide, smooth, lightly sclerotized, with three pairs of setae (st1–st3) and two pairs of lyrifissures (iv1, iv2), with region anteriad iv1 (where st1 is inserted) even less sclerotized; posterior margin with irregular incisions; distances st1–st3 62 62 (59–62) and st2–st2 54 52 (49–54). Each st4 seta inserted in a metasternal plate, together with a lyrifissure iv3. Genital shield smooth, bearing st5; distance st5–st5 49 45 (42–49). Lyrifissure iv5 in the unsclerotized cuticle, approximately in level with posterior shield margin. Ventrianal shield reduced, smooth and ovoid, with only one pair of pre-anal setae (JV2); 77 74 (71–79) long, 37 37 (35–39) wide at anus level; pre-anal pores (gv3) rounded and 2 2 (2–3) apart. With five pairs of opisthogastric setae on unsclerotized cuticle (JV1, JV4, JV5, ZV1 and ZV2), of which JV5 43 43 (42–44) long, always occupying the posterodorsal region of the idiosoma in microscopic mounts, and three pairs of lyrifissures (ivo). Metapodal plates not visible.
Spermatheca — (Figs. 1C, 2D-E). Calyx trumpet-shaped, 30 28 (26–30) long; atrium bulbous, c-shaped, attached to the calyx without neck.
Chelicera — (Figs. 1D, 2F). Fixed digit 20 20 (19–20), with a subapical tooth in addition to the apical tooth; pilus dentilis stout but discreet. Movable digit 17 18 (17–19), with two teeth well separated, in addition to the apical tooth.
Legs — (Fig. 1E). Macrosetae absent. Chaetotaxy: genu II, 2-2/1,2/0-1; genu III, 1-2/1,2/0-1.
The epithet nordestinus is a Portuguese adjective meaning ''from the northeast'', the Brazilian region where the types were collected.
Serraseius nordestinus Araújo & Oliveira sp. nov. is the second species of the genus. The new species can be separated from Serraseius caicara Moraes, Barbosa & Castro, 2013 by having setae j5, z2, Z4, S2, S4 and S5 over 40% shorter; longer and trumpet-shaped calyx of spermatheca, instead of short and funnel-shaped; seta S5 inserted on the unsclerotized cuticle in the new species, instead of on the dorsal shield; and pre-anal pores almost touching each other, instead of well apart and closer to lateral shield margin.
Unknown.
Holotype female and nine paratype females collected by I.F. Araújo on 25 August 2022 from leaves of Ficus gomelleira Kunth (Moraceae) in Recife (8°00′33.8″S, 34°56′45.0″W), Pernambuco state, Brazil, deposited in the mite collection of Universidade Federal Rural de Pernambuco - UFRPE; four paratype females collected on 3 October 2022, other data the same as for the holotype, but deposited in the mite collection of Departamento de Entomologia e Acarologia da Escola Superior de Agricultura ''Luiz de Queiroz'', Universidade de São Paulo (ESALQ-USP), Piracicaba, São Paulo state, Brazil; three paratype females collected on 25 August 2022 and 9 November 2022, other data the same as for the holotype, deposited in the mite collection of Universidade Estadual de Santa Cruz – UESC, Ilhéus, Bahia state, Brazil. Types collected with license 83232-1, issued by Sistema de Autorização e Informação em Biodiversidade – SISBIO/ Instituto Chico Mendes de Conservação da Biodiversidade – ICMBio e Ministério do Meio Ambiente do Brasil.
The analysis of the new species led to the conclusion that the dorsal setae interpreted by Moraes et al. (2013) as Z1 is actually S2. This conclusion was based on the location of the setae in relation to the position of the pores and lyrifissures on the dorsal shield. According to Athias-Henriot (1975), the setae next to lyrifissure idl1 (not clearly distinguishable in the original description of the genus) is S2, instead of Z1, as noted in Figures 1A and 2A of this publication. With this change, the idiosomal setal pattern for Serraseius needs to be changed from 10A:7D/JV-3:ZV-3 to 10A:7F/JV-3:ZV-3, the same pattern reported by Barbosa et al. (2014) for Ingaseius Barbosa, Rocha & Ferla. Other features common to these genera are the absence of leg macrosetae, chelicerae with few teeth, and ventrianal shield longer than wide and with only one pair of setae (JV2). However, Ingaseius differs from Serraseius by having j3– j6, J5, z4, z5, S4, S5, R1 and JV5 short and smooth, dorsal shield without a distinct waist at the level of R1, posterior margin of the sternal shield concave, with st3 inserted in a separate plate (Barbosa et al. 2014). The analysis of the new species also showed that the calyx of the spermatheca in Serraseius can be trumpet-shaped and that S5 of species of this genus can be inserted off the dorsal shield, differently from what was reported in the type species of this genus.
The Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), for granting the scholarship to the first author. To the staff members of Dois Irmãos State Park, for the logistical support. To Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), for the financial support (Proc. No. 306092/2021–2).