Neocypholaelaps geonomae, De, Gilberto J. & Narita, João P. Z., 2010

De, Gilberto J. & Narita, João P. Z., 2010, Description of a new species of Neocypholaelaps (Acari: Ameroseiidae) from Brazil, with a key to the world species, Zootaxa 2554, pp. 37-44 : 38-42

Neocypholaelaps geonomae n. sp.

Diagnosis. Female with dorsal shield posteriorly rounded, with 29 pairs of setae, none of which inserted on tubercles and 26 of which barbed; setae j4, J2 and z6 stout; setae j5, j6 and z5 setiform, smooth and smaller than other dorso-idiosomal setae. Peritreme reaching level between setae j1 and j2. Sternal shield wider than long; st3 on unsclerotised cuticle. Seta Jv4 about 0.7 times as long as seta Jv5.

Adult female ( Fig. 1 ) (5 specimens measured)

Gnathosoma ( Figs 1 A–C): Fixed cheliceral digit 23 long, with a single, small tooth slightly posterior to apical tooth; with a membranous lobe externally attached to it; movable cheliceral digit 27 long, edentate. Antiaxial and dorsal lyrifissures of median cheliceral segment distinct; dorsal seta absent. Epistome with anterior projection rounded to triangular and serrated; with a row of denticles at the base of the projection; in some specimens, a second, interrupted row of denticles is present anteriorly to the row at the base of the projection. Palp apotele 2-tined. Deutosternum narrow; transversal rows of denticles barely discernible, with five rows of few denticles each (exact numbers not possible to count). With two pairs of lines of distinct denticles laterad of deutosternal margin, one anterior and the other posterior to seta sc. Corniculi undivided, slightly sinuate, convergent, each superposed by a hyaline membrane. In most specimens, internal malae seemingly undivided, distally rounded and with smooth margin; in others, with a central longitudinal line dividing it in two distally rounded structures. Hypostomal setae lengths: h1 20, h2 17, h3 16, sc 19.

Dorsal idiosoma ( Fig. 1 D): Dorsal shield entire, reticulated, 414 (410-417) long and 310 (308-312) wide at level of s6; apparently with three pairs of pores (posteromediad of r4; mediad and about in tranversal line with Z1; posterior and slightly laterad of Z2) and 18 pairs of lyrifissures (slightly posterior and laterad of j1; anterior to j3; anterolaterad to j4; posterior to z2; mediad and about in transverse line with z4; posterior and slightly mediad of z5; posteromediad of r4; laterad and about in transverse line with j6; mediad and about in transverse line with Z1; posterolaterad of r6; anterolaterad of S2; laterad and about in transverse line with J2; posteromesad of Z2; mesad and about in transverse line with Z4; posteromediad of S3; posteromesad of S4; posteromesad of Z4; posteromesad of S5). Lengths of dorsal setae: j1 27 (25-30), j2 29 (27-32), j3 25, j4 24 (23-25), j5 16 (15-17), j6 16 (15-16), J2 25, J4 27 (25-30), z2 27, z4 25, z5 16 (15-17), z6 24 (23-25), Z1 23 (22-25), Z2 23 (22-25), Z4 23 (22-25), Z5 31 (30-32), s1 24 (23-25), s2 28 (27-30), s4 25 (23-27), s5 28 (27- 30), s6 28, S2 27 (25-30), S3 27, S4 27 (25-30), S5 27 (25-30), r2 26 (25-27), r3 27 (25-30), r4 28 (27-30), r5 28 (27-30). Seta j1 leaf-shaped and barbed; setae j5, j6 and z5 setiform and smooth; other setae stout and barbed.

Ventral idiosoma ( Fig. 1 E–G): Base of tritosternum 10 long; laciniae fused along basal one-fifth of their total length (65 long). Sternal shield smooth, 55 (52-57) long at midline and 85 (82-87) wide at level of st2, bearing 2 pairs of setae (st1 and st2) and two pairs of lyrifissures; setae st3 and st4 on unsclerotised cuticle; third pair of sternal lyrifissure posteromesad of st3. Genital shield smooth, 84 (83-85) wide at the widest level, posteriorly convex, bearing st5; flanked by two pairs of lyrifissures, the anterior, next to st5, distinctly larger than the posterior. Anal shield reticulated and oval, 85 long at midline and 147 (145-150) wide at the widest level. Setae Jv1-Jv5 and Zv2 on unsclerotised cuticle. Opisthogaster with two pairs of elongate platelets (posterolaterad of Jv1; anterolaterad of Zv2) and six pairs of lyrifissures (posterolaterad of Jv1; laterad and about in transverse line with Zv2; posterolaterad of Zv2; posterolaterad of Jv3; posterolaterad of Jv4, anteromediad of Jv5). Lengths of ventral setae: st1 20 (18-22), st2 19 (18-20), st3 20 (18-22), st4 19 (18-20), st5 20 (18-22), Jv1 14 (12-17), Jv2 10, Jv3 10, Jv4 19 (17-22), Jv5 27 (25-30), Zv2 10, para-anal 12, post-anal 11 (10-12). Unsclerotised opisthogastric cuticle striated; striae without granulation. Seta Jv5 stout and barbed; other ventral setae setiform and smooth. Endopodal shield represented by a platelet between coxae II and III and a narrower and more elongate platelet along coxae III and IV. Exopodal shield of irregular width, with projections between legs II and III and legs III and IV; with a lyrifissure at level between coxae I and II; abutting peritreme at level of seta j1; exopodal shields of both sides fusing to each other and to dorsal idiosomal shield at region anterior to setae j1.

Peritreme and peritrematal shield ( Figs 1 D, 1G): Peritreme extending forward to level between j1 and j2 (level of coxa I). Peritrematal shield narrow, fused to dorsal shield at level between s1 and j2, and to exopodal shield behind stigma; with a lyrifissure at level of coxa III.

Spermathecal apparatus ( Fig. 1 H): Induction pore apparently at postero-proximal region of coxa III; infundibulum (35 long) distinctly wider than tubulus (215 long), leading to wider ramus (15 long); rami apparently close to each other.

Legs ( Fig. 1 I): All legs with pulvilli and claws. Lengths of legs: I: 369 (362-375), II: 344 (337-350), III: 269 (362-375), IV: 416 (412-420). 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 (1-2/1, 1/0- 1), 6 (1-2/1, 1/0-1); genua: 12 (2-3/2, 2/1-2), 11 (2-3/1, 2/1-2), 9 (2-2/1, 2/1-1), 9 (2-2/1, 3/0-1); tibiae: 12 (2-3/2, 2/1-2), 10 (2-2/1, 2/1-2), 8 (2-1/1, 2/1-1), 9 (2-2/1, 2/1-1); tarsi: not counted, 17, 17, 17. Many (mostly dorsal) setae of femur and genu of all legs barbed; other setae smooth.

Adult male ( Fig. 2 A–F) (2 specimens measured)

Gnathosoma ( Fig. 2 A–D): Fixed cheliceral digit 32-35 long, with a single tooth, next to apical tooth, and with an inflated structure of apparently variable shape, in some specimens bearing a distal spine-like extension; movable cheliceral digit 40-43 long, edentate. Epistome and apotele similar to female. Spermatodactyl 32–37 long, medially inflated and apparently concave on the ventral side; distal portion slightly sinuous and attenuate. Hypostome similar to female, corniculi distinctly less convergent in one of 4 specimens. Hypostomal setae of the following lengths: h1 25, h2 (not possible to measure), h3 20, sc 24.

Dorsal idiosoma ( Fig. 2 E): Dorsal shield entire and mostly reticulated, with a rugose central band between setae j1-J2 and with a series of marginal, diagonal ridges between setae s 6 and S3; 427-430 long and 343-350 wide at level of r5. Apparently with a pair of pores (mediad and about in transverse line with S3) and 11 pairs of lyrifissures (laterad and about in transverse line with j1; anterolaterad of j3; laterad and about in transverse line with j4; posterolaterad of s2; posterior and about in longitudinal line with z5; laterad and about in transverse line with J2; anterolaterad of S2; anteromediad of J4; posteromediad of S3; posterolaterad of S4; anterior and in longitudinal line with S5). Lengths of dorsal setae: j 1 22-27, j 2 30-32, j3 45-47, j4 45-47, j 5 13- 15, j 6 15-17, J2 60-63, J4 48-50, z2 38-40, z4 40-42, z 5 13-15, z6 35-37, Z1 40-45, Z 2 27-32, Z4 35-37, Z5 33- 35, s 1 20 -25, s2 38 -40, s4 40 -45, s5 35 -42, s6 38 -40, S2 35 -37, S 3 30 -32, S 4 30 -32, S 5 30 -32, r2 35, r3 38-40, r4 35-37, r5 40. Setae j5, j6 and z5 setiform and smooth; J2 rod-shaped and barbed; other setae leaf-shaped and barbed.

Ventral idiosoma ( Fig. 2 F): Base of tritosternum not differentiated; laciniae fused along basal one-third of their total length (52 long). Sternogenital shield smooth, rectangular, 202 long and 93 wide at level of st3, bearing five pairs of setae (st1-st5) and three pairs of lyrifissures. A pair of lyrifissures posterolaterad of st5, on unsclerotised cuticle. Ventri-anal shield smooth and oval, 125 long and 162 wide at the widest level, bearing seta Jv3. Setae Jv1, Jv2, Jv4, Jv5 and Zv2 on unsclerotised cuticle. Opisthogaster with two pairs of lyrifissures (posterolaterad of Jv1; posterolaterad of Jv3). Lengths of the ventral setae: st 1 13-15, st2 17, st3 17, st4 17, st 5 17-19, Jv 1 15-17, Jv 2 10-12, Jv 3 10-12, Jv4 15, Jv5 38-40, Zv2 10, para -anal 15, post -anal 15. Unsclerotised opisthogastric cuticle striated; striae without granulation. Endopodal shield represented by a platelet between coxae II and III, a platelet between coxae III and IV and a platelet along coxa IV. Exopodal shield similar to female, but the lyrifissure between coxae I and II absent and exopodal shield abutting peritreme at level of seta j2.

Peritreme and peritrematal shield: Similar to female.

Legs: All legs with pulvilli and claws. Lengths of legs: I – 367-375, II – 337-350, III – 360-362, IV – 375- 485. Chaetotaxy of legs similar to female.

Material examined. Holotype female and one paratype female from inflorescences of Geonoma brevispatha Barb. Rodr. (Arecaceae) , São Pedro, State of São Paulo, Brazil, May 16, 2000, collected by L.V.F. da Silva; 5 paratype females and 1 paratype male, November 11, 2000, other data as for holotype; 1 paratype female and 1 paratype male, August 10, 2000, other data as for holotype; 2 paratype males from inflorescences of Geonoma schottiana Mart. , in Cananéia, State of São Paulo, Brazil, April 19, 2000. All paratypes collected by G.P. Arruda. The types 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 name geonomae refers to “from Geonoma ”, the genus of the plant substrate on which the types were collected.

Remarks. This new species fits the characterisation of Neocypholaelaps by having dorsal shield not rugose, undivided corniculi, cheliceral digits edentate or with a single subapical tooth and all legs with a pair of claws. It is similar to N. stridulans ( Evans, 1955) , N. favus Ishikawa, 1968 , N. varipilosa Elsen, 1972 a and N. apicola Delfinado-Baker & Baker, 1983 . However, the female of N. stridulans has the sternal shield longer than wide, each seta st3 inserted on a platelet, and a spermathecal apparatus with tubuli fused into a single structure that leads to the sacculus, as shown by Evans (1963a) for N. cocos Evans, 1963 a. The female N. favus has setae j6 and z5 barbed, while the male has all dorsal shield setae elongate and with sharp tips. Female of N. varipilosa has narrower dorsal shield (about 1.6 as opposed to about 1.3 as long as wide in the new species here described), seta j4 smooth, sternal shield reticulated and no platelet posterolaterad of Jv1. The female of N. apicola has distinctly shorter seta j5 and granulate opisthogastric striae; the male of the latter is however readily distinguished from that of the new species, by having dorsal shield setae elongate and with sharp tips and ventri-anal shield with 3 pairs of setae.

The distinctly less convergent corniculi of one of the males of this new species do not correspond to what is typical for species in this genus; according to Evans (1963a), Neocypholaelaps species have convergent corniculi. However, the seemingly abnormal orientation of the corniculi of that male is most probably due to the mobility of these structures, as indicated by Evans (1963a).

Figures

FIGURE 1. Neocypholaelaps geonamae n. sp. Female. A. Lateral view of chelicera; B. Variations of epistome; C. Ventral view of gnathosoma; D. Dorsal view of idiosoma; E. Detail of tritosternum; F. Ventral view of idiosoma; G. Right peritreme and associated shields (a = dorsal shield; b = peritrematal shield; c = exopodal shield; d = striated unsclerotised cuticle between peritreme and exopodal shield); H. Spermathecal apparatus; I. Pre-tarsus I. Scales in micrometres. Pores and lyrifissures enlarged to allow their differentiation.

FIGURE 2. Neocypholaelaps geonamae n. sp. Male. A. Lateral view of chelicera; B. Variation of the lateral view of spermatodactyl; C. Dorso-ventral view of spermatodactyl; D. Variation of pilus dentilis; E. Dorsal view of idiosoma; F. Ventral view of idiosoma. Scales in micrometres. Pores and lyrifissures enlarged to allow their differentiation.