Neocypholaelaps kreiteri, Narita, João Paulo Z., Pédelabat, Marie & De Moraes, Gilberto J., 2013

Narita, João Paulo Z., Pédelabat, Marie & De Moraes, Gilberto J., 2013, A new species of Neocypholaelaps Vitzthum (Acari: Ameroseiidae), with notes on the cheliceral lobes and ventral pore-like structures of mites of this family, Zootaxa 3666 (1), pp. 1-15 : 2-13

Neocypholaelaps kreiteri n. sp.

Diagnosis. Female with dorsal shield totally reticulate, with reticula formed by simple lines; with 29 pairs of setae, none of which inserted on tubercles, all stout and barbed, with j1 broader and leaf-shaped. Sternal shield wider than long, bearing setae st1 and st2; st3 and st4 on unsclerotised cuticle. Seta Jv4 about 0.8 times as long as Jv5. Peritreme almost reaching level of j1. Male with j1 leaf-shaped and barbed; J4 stout and barbed; Z2, Z4, Z5, s4 – s6, S2 – S5, r2 – r5 stout, barbed and broader distally; other setae setiform and smooth; J2 well anteriad of J4; with a circular lobe on soft cuticle near s6, followed by a stippled band along dorsal shield margin; with a pair of small lobes posterior of J4; femur IV and genu IV bearing a disto-dorso-posterolateral spine.

Adult female ( Figs 1–8 ) (5 specimens measured).

Gnathosoma: Fixed cheliceral digit 28 (25–30) long, with a subapical tooth and a membranous lobe attached antiaxially to the digit; movable cheliceral digit 23 (20–25) long, only with apical tooth ( Fig. 1 ). Antiaxial and dorsal lyrifissures of median cheliceral segment distinct; dorsal seta absent. Epistome ( Fig. 2 ) with anterior margin truncate and denticulate, with two rows of denticles immediately posterior to it. Palp apotele 2-tined. Deutosternum narrow; transverse rows of denticles not discernible ( Fig. 3 ). Hypostome with two pairs of rows of denticles laterad of deutosternal margin, one posterior to sc and running across most of the region between deutosternum and margin of hypostome, the second between sc and h2, much shorter than the first. Corniculi undivided, subparallel to each other, each superposed by a membranous lobe whose bases are partially overlapped by a shorter central lobe.

Dorsal idiosoma ( Fig. 4 ): Dorsal shield entire, totally reticulate; reticula formed by simple lines; 403 (395– 410) long and 270 (260–280) wide at level of s6; with 29 pairs of setae, apparently seven pairs of pores (posterolaterad of j2; anteromesad of z4; posteromesad of z5; posterolaterad of z6; posteromesad of r4; posteromesad of S3, posteromesad of S5) and 14 pairs of lyrifissures (posterolaterad of j1; posterolaterad of s2; anteromesad of r5; anteromesad of z6; anterolaterad of J2; posterolaterad of J2; mesad of Z1; posterolaterad of Z2; anterolaterad of S2; posterolaterad of J4; anteromesad of Z5; posterolaterad of Z5; anterolaterad of S4; anterolaterad of S5). Seta j1 leaf-shaped and barbed; other dorsal setae stout and barbed; according to the position of the setae in the mounted specimens, barbs of setae j4 – j6 not always clearly seen. Measurements of setae as in Table 1 .

Ventral idiosoma ( Fig. 5 ): Base of tritosternum 10 long and 16 wide; laciniae fused along basal one-third of their total length (80 long). Sternal shield smooth, 69 (62-75) long at midline and 83 (80–85) wide at level of st2, bearing two pairs of setae (st1 and st2) and two pairs of lyrifissures (iv1, iv2). Setae st3 and st4 on unsclerotised cuticle. Third pair of lyrifissures (iv3) posteromesad to st3. Genital shield smooth, 79 (75–83) wide at the widest level, slightly convex posteriorly, bearing st5; with a pair of pores (gv2, anterior; see remarks) and a pair of lyrifissures (iv5, posterior) on unsclerotised cuticle postero-laterad of st5. Anal shield smooth and oval, 97 (93– 100) long at midline and 115 (110–120) wide at the widest level; with a curved transverse line immediately anterior to cribrum. Opisthogastric setae (Jv1 – Jv5, Zv2) on unsclerotised cuticle. With a sclerotised transverse line immediately posterior of margin of genital shield. Opisthogaster with five pairs of lyrifissures and a pair of elongate metapodal platelets. Unsclerotised opisthogastric cuticle striate; striae without granulation. Setae Jv4 and Jv5 stout and barbed; other ventral idiosomal setae setiform and smooth; Jv4 about 0.8 times as long as Jv5.

Remnants of endopodal shield represented by a triangular platelet between coxae II and III, and a narrow, curved platelet between coxae III and IV. Exopodal shields of irregular width, with projections between coxae II and III and coxae III and IV. Measurements of setae as in Table 2 .

Peritreme and peritrematal shield ( Fig. 6 ): Peritreme almost reaching level of j1. Peritrematal shield narrow, fused to dorsal shield at level of j2, to each other anteriorly and to exopodal shield behind stigma; with a large pore at level of coxa III (gd3 of Athias-Henriot, 1975; gp2 of Lindquist & Moraza, 2009) surrounded by a stippled region that probably corresponds to muscle insertion (see Athias-Henriot, 1975); with two lyrifissures behind stigma.

Spermathecal apparatus ( Fig. 7 ): Induction pore apparently at postero-proximal region of coxa III; tubuli fusing before entering sacculus by a ca. 50 long common duct.

Legs: All legs with pulvilli and claws ( Fig 8 ). Lengths of legs: I—360 (340–370), II—302 (290–315), III—318 (310–330), IV—407 (390–440). 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. Posterior seta of coxa II and dorsal setae of femur, genu and tibia of all legs stout and barbed; other setae setiform and smooth.

Adult male ( Figs 9–12 ) (5 specimens measured).

Gnathosoma ( Fig. 9 ): Fixed cheliceral digit 25 long, with a subapical tooth; membranous lobe not possible to see in the available specimens; movable cheliceral digit 22 long, only with apical tooth. Spermatodactyl 50 long, slightly curved downward and then expanded, distal portion expanded but acuminate at the tip. Epistome, hypostome, corniculi and apotele similar to female.

Dorsal idiosoma ( Fig. 10 ): Dorsal shield entire and mostly reticulate, with a smooth band between j1 and j6; 391–475 long and 310–400 wide at level of s6; with 29 pairs of setae, apparently seven pairs of pores (posterolaterad of j2; anteromesad of z4; posterolaterad of z5; anteriad of s5; anteromesad of Z1; anterolaterad of S4; posteromesad of S5) and 12 pairs of lyrifissures (posterolaterad of j1; anteromesad of r2; anterolaterad of s5; posteromesad of s6; posterolaterad of s6; mesad of Z1; laterad of S2; posterolaterad of J2; posterolaterad of J4; anterolaterad of S4; anterolaterad of S5; posterolaterad of Z5). Setae j1 leaf-shaped and barbed; setae J4 stout and barbed; Z2, Z4, Z5, s4 – s6, S2 – S5, r2 – r5 stout, barbed and broader distally; other setae setiform and smooth; setae J2 well anteriad of J4. Shield with a circular lobe on soft cuticle near s6, followed by a stippled band along margin of dorsal shield, from region between s6 and S2 to region between S3 and S4, and a pair of small lobes posteriad of J4. Measurements of setae as in Table 1 .

Ventral idiosoma ( Fig. 11 ): Base of tritosternum 8 long and 15 wide; laciniae fused along basal one-third of their total length (60 long). Sternogenital shield smooth, subrectangular, constricted behind st2, with posterior half roundish; 212 (205–218) long, 93 (88–98) wide at level of st2 and 105 (100–110) wide at level of st3, bearing five pairs of setae (st1 – st5) and three pairs of lyrifissures (iv1–iv3). Unsclerotised cuticle postero-laterad of st5 with a pore (gv2) followed by a lyrifissure (iv5) on each side. Anal shield smooth and oval, 108 (100–115) long and 135 (130–140) wide at the widest level; with curved transverse line immediately anterior to cribrum; Opisthogastric setae (Jv1–Jv5, Zv2) on unsclerotised cuticle. Opisthogaster with three pairs of lyrifissures, a pair of metapodal platelets immediately posteriad of tip of peritrematic shield and a pair of subrectangular platelets posterolaterad of Jv2. Unsclerotised opisthogastric cuticle striate; striae without granulation. Setae Jv4 and Jv5 stout and barbed; other ventral idiosomal setae setiform and smooth. Remnants of endopodal shield represented by an elongate platelet next to coxa I, an L-shaped platelet between coxae II–III, an ellipsoid platelet between coxae III and IV and an elongate, straight platelet next to coxa IV. Exopodal shield similar to female. Measurements of setae as in Table 2 .

Peritreme and peritrematal shield: Similar to female.

Legs ( Fig. 12 ): All legs with pulvilli and claws. Lengths of legs: I—390 (375–405), II—315 (290–340), III— 345 (305–395), IV—505 (435–575). Chaetotaxy of legs similar to female. Femur, genu and tibia IV with two to three pore-like structures on dorsal surface. Femur and genu IV each with a disto-dorso-posterolateral spine. Shape of setae similar to female.

Deutonymph ( Figs 13–14 ) (3 specimens measured).

Gnathosoma: Fixed cheliceral digit 26 (23–28) long with a subapical tooth and an antiaxial membranous lobe; movable cheliceral digit 23 (20–25) long, only with apical tooth. Epistome, hypostome, corniculi and apotele similar to female.

Dorsal idiosoma ( Fig. 13 ): Dorsal shield entire, totally reticulate; reticula formed by simple lines; 348 (315– 380) long and 253 (215–290) wide at level of s6; with 29 pairs of setae, apparently six pairs of pores (posterolaterad of j2; posterolaterad of j4; posteromesad of z5; anteromesad of r5; anteromesad of Z1; posteromesad of S3) and four pairs of lyrifissures (posterolaterad of j1; posterolaterad of s6; anterolaterad of S4; mesad of S5). Seta j1 leaf-shaped and barbed; setae j2 – j6, J2, z2, z4 – z6, Z1, s1 – s2, s4 setiform and smooth; other setae stout and barbed. Measurements of setae provided in Table 1 .

Ventral idiosoma ( Fig. 14 ): Base of tritosternum 10 long and 15 wide; laciniae fused along basal one-third of their total length (60 long). Sternal shield smooth, subrectangular, constricted behind st2; 185 (165–205) long at midline and 82 (80–83) wide at level of st3, bearing five pairs of setae (st1 – st5) and three pairs of lyrifissures (iv1– iv3). Unsclerotised cuticle postero-laterad of st5 with a pore (gv2; lateral) followed by a lyrifissure (iv5; mesal) on each side. Anal shield smooth and oval, 54 (44–73) long at midline and 65 (50–80) wide at the widest level; cribrum distinct near posterior margin of anal shield. Opisthogastric setae (Jv1 – Jv5, Zv2) on unsclerotised cuticle. Opisthogaster with two pairs of lyrifissures. Unsclerotised opisthogastric cuticle striate; striae without granulation. Setae Jv5 stout and barbed other ventral idiosomal setae setiform and smooth. Measurements of setae as in Table 2 .

Peritreme and peritrematal shield: Peritreme reaching level of j2. With a large pore at level of coxa III surrounded by a stippled region, as reported.

Legs: All legs with pulvilli and claws. Lengths of legs: I—282 (253–310), II—253 (235–271), III—271 (245– 296), IV—323 (245–380). Chaetotaxy of legs I–IV: same as female. Setal shape similar to female.

Protonymph ( Figs 15–16 ) (3 specimens measured).

Gnathosoma: Fixed cheliceral digit 27 (23–31) long, with a subapical tooth and an antiaxial membranous lobe; movable cheliceral digit 19 (18–21) long, only with apical tooth. Epistome, hypostome, corniculi and apotele similar to female.

Dorsal idiosoma ( Fig. 15 ): Dorsal shield entire, smooth; 264 (255–273) long and 179 (168–190) wide at level of s6; with 25 pairs of setae, apparently with five pairs of pores (posterolaterad of j2; anteromesad of z4; posterolaterad of s4; posteromesad of S3; posteromesad of S4) and a pair of lyrifissures (anteromesad of Z1). Seta j1 stout and barbed; J4, Z2, Z4, Z5 and S2 – S5 stout and barbed; other dorsal setae setiform and smooth. Measurements of setae as in Table 1 .

Ventral idiosoma ( Fig. 16 ): Base of tritosternum 9 long and 11 wide; laciniae fused along basal one-third of their total length (53 long). Sternal shield smooth, very lightly sclerotised, 116 (100–132) long at midline and 68 (65–70) wide at level of st2, bearing three pairs of setae (st1 – st3); unsclerotised cuticle postero-laterad immediately posterior to sternal shield with a pore (gv2; lateral) and a lyrifissure (iv5; mesal) on each side. Anal shield smooth 45 (40–50) long at midline and 51 (48–54) wide at the widest level; cribrum distinct around post-anal seta. Opisthogastric setae (Jv1, Jv2, Jv5 and Zv2) on unsclerotised cuticle. Opisthogaster with two pairs of lyrifissures. Unsclerotised opisthogastric cuticle striate; striae without granulation. Setae Jv5 stout and lightly barbed other ventral idiosomal setae setiform and smooth. Measurements of setae as in Table 2 .

Peritreme and peritrematal shield: Peritreme reaching level between r2 and r3. With a large pore at level of coxa III as reported for female.

Legs: All legs with pulvilli and claws. Lengths of legs: I—242 (237–250), II—218 (210–225), III—218 (211– 225), IV—255 (250–260). Chaetotaxy of legs I–IV: coxae: 2, 2, 2, 1; trochanters: 4, 4, 4, 4; femora: 10 (2-2/1, 2/1- 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, 15, 15, 15.

Larva ( Figs 17–18 ) (3 specimens measured).

Gnathosoma: Fixed cheliceral digit 17 long, not possible to determine whether there is a tooth close to the apical tooth; with an antiaxial membranous lobe; movable cheliceral digit 16 long, only with apical tooth. Epistome with anterior margin truncate but smooth and with a single row of denticles immediately posterior to it. Apotele and corniculi similar to female.

Dorsal idiosoma ( Fig. 17 ): Podonotal region and region between S4 and S5 punctate; dorsal shield margins indistinct; with 16 pairs of setae, apparently with a pair of pores anterolaterad of S4 and no distinguishable lyrifissures. Seta j1 stout and barbed; other dorsal setae setiform and smooth. Measurements of setae as in Table 1 .

Ventral idiosoma ( Fig. 18 ): Base of tritosternum 3 long and 9 wide; laciniae fused along basal one-third of their total length (46 long). Sternal shield lightly sclerotised, punctate, bearing only setae st1 – st3. Opisthogastric setae (Jv1, Jv2, Jv3 and Zv2) on unsclerotised cuticle. Opisthogaster with a pair of lyrifissures. All ventral setae setiform and smooth. Measurements of setae provided in Table 2 .

Legs: All legs with pulvilli and claws. Lengths of legs: I—213 (212–214), II—197 (193–200), III—198 (191– 205). Chaetotaxy of legs I–IV: coxae: 2, 2, 2; trochanters: 4, 4, 4; femora: 10 (2-2/1, 2/1-2), 7 (1-2/1, 2/0-1), 5 (1-2/ 1, 1/0-0); genua: 8 (1-2/1, 2/1-1), 6 (1-2/0, 2/0-1), 6 (1-2/0, 2/0-1); tibiae: 8 (1-2/1, 2/1-1), 7 (1-1/1, 2/1-1), 7 (1-1/ 1, 2/1-1); tarsi: not counted, 13, 13..

Type specimens. All type specimens collected from inflorescences of Cocos nucifera L. on La Réunion Island, by G.J. de Moraes and S. Kreiter. Holotype female collected on March 2, 2011; 26 adult paratype females, 12 paratype males, 6 paratype deutonymphs, 6 paratype protonymphs and 8 paratype larvae were collected on March 2 and 12, 2011. Of these, holotype female, 16 paratype females, 7 paratype males, 3 paratype deutonymphs, 2 paratype protonymphs and 4 paratype larvae deposited at Departamento de Entomologia e Acarologia, Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba, State of São Paulo, Brazil (ESALQ—USP); remaining specimens deposited at SupAgro INRA Acarology Collection, Montpellier, France.

Other specimens examined. A further 48 adult females, 9 adult males, 5 deutonymphs, 1 protonymph and 1 larva, with the same collection data as type specimens; all deposited at ESALQ—USP.

Etymology. This new species is named in honor of Prof. Dr. Serge Kreiter, SupAgro, France, for the excellent contribution he has given to acarology.

Remarks. The stippled band on the dorsal shield, between setae s6, S2, S3, S4, together with the spurs found on leg IV, corresponds to what was referred to a “stridulating organ” by Evans (1955), who considered that males of N. stridulans could use it to produce a courtship sound. Neocypholaelaps kreiteri is most similar to N. stridulans and N. cocos , whole adult males have the “stridulating organ” of Evans (1955). However, in adult males of those species, the setae mentioned as J2 and J4 are nearly in a transverse line, whereas in N. kreiteri , J2 (as interpreted in this publication) is well anteriad of J4. Evans (1963) considered the stouter of those setae to be J2, most probably because of their slightly anterior insertion in the relation to the much shorter, setiform and slightly lateral setae then interpreted as J4, and because in males of some other species of the same genus, as in Neocypholaelaps ampullula (Berlese, 1910) , redescribed in that same paper, J2 is stout and longer than the posterior J4. In males of N. kreiteri the anterior of these setae (J2) is setiform, much shorter and slightly closer together than the posterior, stouter setae (J4).

Adults of both sexes of N. kreiteri differ from those of N. stridulans by the pattern of the dorsal shield, which in N. stridulans is composed of a polygonal network of double punctate lines enclosing punctate cells; adult females of N. kreiteri have st3 on unsclerotised cuticle, which in N. stridulans is placed on platelets. Adult females of N. kreiteri further differ from adult females of N. cocos by the shape of several dorsal shield setae. All adult females of N. kreiteri have dorsal shield reticulate and all dorsal shield setae stout and barbed, although depending on the orientation of the specimens, barbs of setae j4 – j6 are not always clearly seen. Neocypholaelaps cocos was originally described by Evans (1963) from specimens collected in Solomon Islands; it was also reported by Halliday (1997) from Australia. Adult females of this species were mentioned in the original description to have dorsal shield ornamented with polygonal network of simple lines, setae s1, s2, i2 – i5, z1 – z3, r3, J2 and Z2 setiform and smooth and other setae stout and strongly serrated. Judging from the illustrations given in the original description, the author was seemingly referring to j2, z2, j3, j4, j5, j6, z4, z5, z6, s2, J2, Z1 as interpreted in this paper, and he apparently did not mention his r2, interpreted as s 1 in this paper, which was also illustrated as setiform and smooth in the original description. Halliday (1997) mentioned from the Australian specimens identified as N. cocos to have unornamented dorsal shield; he repeated the information given in the original description in relation to the shape of the dorsal shield setae, although mixing the setal terminology used in the original description with the terminology of Lindquist & Evans (1965).

The key provided by Moraes & Narita (2010) and modified by Narita et al. (2011) could be again modified to allow the separation of this new species from the other Neocypholaelaps , by including a new couplet 8b between couplets 8a and 9 of Narita et al. (2011) and by modifying couplet 8a as follows:

8a. Setae j2 – J2, z1 – Z1, s1 and s2 slender and smooth; ornamentation of dorsal shield consisting of a polygonal network of simple lines enclosing smooth cells................................................ Neocypholaelaps cocos Evans, 1963 - All dorsal shield setae stout and barbed (except j1, leaf-shaped and barbed); ornamentation of dorsal shield consisting of a polygonal network of simple lines enclosing smooth cells or of double punctate lines enclosing punctate cells.......... 8b 8b. Ornamentation of dorsal shield consisting of a polygonal network of simple lines enclosing smooth cells; st3 on unsclerotised cuticle.......................................................................... Neocypholaelaps kreiteri - Ornamentation of dorsal shield consisting of a polygonal network of double punctate lines enclosing punctate cells; st3 on platelet............................................................................................. 9 Notes on ameroseiid cheliceral lobes

Evans (1963) was probably the first author to refer to the presence of a lobe in the fixed cheliceral digit of Mesostigmata . While presenting a characterisation of Neocypholaelaps Vitzthum , he referred to this structure as a transparent lobed appendage, suggesting that it could represent a modified pilus dentilis. That interpretation was probably related to the fact that when present both of these structures are located on the abaxial face of the digit and because the presence of the former in Neocypholaelaps was related to the absence of the latter, a common structure in other Mesostigmata . He mentioned the lobe to be present in all post-embryonic stages, and in both sexes, despite being smaller in males. In that publication, he illustrated smaller lobe in adult males than in adult females of the N. ampullula (Berlese) and N. stridulans (Evans) . The smaller lobe in adult males has also been reported in the original descriptions or redescriptions ( Baker & Delfinado-Baker, 1985; Delfinado-Baker & Baker, 1983; Ishikawa, 1968; Moraes & Narita, 2010, Silva et al., in press) of the following Neocypholaelaps species: N. apicola, Baker & Delfinado-Baker, N. ceylonicus Narita & Moraes, N. favus Ishikawa, N. geonomae Moraes & Narita and N. phooni Baker & Delfinado-Baker.

The shape of the lobe may vary slightly between specimens of the same species, suggesting they not be sclerotised. In addition to the new species here described, lobes are known to be present in the following Neocypholaelaps species, based on their original descriptions or redescriptions ( Baker & Delfinado-Baker, 1985; Bhattacharyya, 1971; Delfinado-Baker & Baker, 1983; Elsen, 1972; Evans, 1963; Gupta, 1969; Moraes & Narita, 2010; Narita et al. 2011): N. ampullula , N. apicola , N. breviperitremata Elsen, N. ceylonicus, N. cocos Evans, N. geonomae, N. indica Evans, N. leopoldi Elsen, N. novaehollandiae Evans, N. phooni Baker & Delfinado-Baker, N. pradhani Gupta, N. stridulans and N. xylocopae Elsen. Available information does not allow the determination of the possible presence of the lobe in the remaining species of this genus — N. capitis Elsen, N. crocisae Elsen, N. favus Ishikawa, N. hongkongensis Mo, N. malayensis Delfinado-Baker, Baker & Phoon, N. nova Elsen, N. rotundus (Womersley) and N. varipilosa Elsen.

Membranous lobes are also illustrated or mentioned in the original descriptions or redescriptions of the following ameroseiid species: Afrocypholaelaps Elsen— A. africana (Evans) , A. analicullus Ho, Ma, Wang & Severinghaus and A. lindquisti (Prasad) ; Brontispalaelaps Womersley— B. marianneae Halliday ; Epicriopsis Berlese— E. stellata Ishikawa and E. walteri Halliday ; Hattena Domrow— H. cometis Domrow, H. floricola Halliday, H. incisa Halliday and H. rhizophorae Faraji & Cornejo ; and Sertitympanum Elsen & Whitaker— S. separationis Elsen & Whitaker. Nothing has been reported in the literature in relation to the possible presence of membranous lobes in B. leveri Womersley , but an examination of specimens from Thailand identified as this species could not show the presence of this structure. Membranous lobes have not been mentioned or illustrated in males of any of these species, not even in the detailed scanning and transmission electron microscopic study of H. cometis by Di Palma et al. (2013). Available information does not allow a conclusive statement about the presence of the lobe in mites of the larger ameroseiid genus, Ameroseius Berlese , but a prominent lobe is present in A. dendrovagans Flechtmann & Flechtmann. Illustrations of the following species suggest it may be present: A. avium Karg, A. bassolsae (Vargas & Polaco), A. corbicula (Sowerby) , A. coronarius De Leon, A. macrochelae Westerboer, A. marginalis Fan & Li and A. wahabi (Ibrahim & Abdel-Samed) . In all of those species, the lobe seems to be less evident, and seemingly more ridge like, extending along the inner edge of the fixed cheliceral digit, than the lobes of species of the previously mentioned genera (except Sertitympanum ). Among these species, a distinct cheliceral lobe in the male fixed cheliceral digit was illustrated only for A. dendrovagans . However, we were not able to see that structure in our examination of three adult males of this species labeled as paratypes. A conclusion about the possible presence of cheliceral lobes in other species would require the examination of representative specimens, given that the structure could have been overlooked because of the inadequate position of the chelicera in the mounted type specimens or because of its difficult visualisation.

Flange-like expansions attached to the fixed cheliceral digit have also been reported in many other Mesostigmata of the suborder Gamasina . These are often simply referred to as lobes, or as membranous lobes, transparent lobed appendages, transparent lobes, hyaline lobes or hyaline flaps (Evans, 1963; Lindquist & Evans, 1965; Flechtmann & McMurtry, 1992; Halliday et al., 1998).

In a revision of the Gamasina group then interpreted as Ascidae, Lindquist & Evans (1965) pointed out the presence of a membranous lobe, transparent lobe or flaplike appendage (and the absence of pilus dentilis) in the species they then placed in the Melicharini, as well as the presence of a small proximal flap (in addition to the pilus dentilis) on the movable cheliceral digit of species of Antennoseius Berlese , of the Ascini. The Melicharini were recently raised to the family level ( Melicharidae ) by Lindquist et al. (2009). An examination of the original descriptions and redescriptions of species of this family showed the presence of a membranous lobe in almost all species for which details about the chelicerae are available; the only species presently placed in this group that instead of the lobe are known to have setiform pilus dentilis are the Orthadenella Athias-Henriot and a few Proctolaelaps Berlese.

Flechtmann & McMurtry (1992) studied the occurrence of membranous lobes in Phytoseiidae . They mentioned that these structures are apparently soft and delicate, having a wide variation in size, shape and position between species, even within a same genus. They studied 15 species of eight genera, noticing that at one extreme, some species had rudimentary lobes, positioned at the base of the fixed digit, whereas in the other extreme, other species had large lobes. In all cases, however, the pilus dentilis was also present.

Absence, presence or variations in shape of the membranous lobe of the ameroseiids, as well as in other Mesostigmata , are expected to be related to differences in their feeding habits.

In melicharids, while many species seem to be mainly flower inhabitants ( Rhinoseius , Spadiseius , Tropicoseius , Xanthippe Naskrecki & Colwell and some Proctolaelaps ), a few have been reported mainly from sweet substrates ( Melichares Hering ) and some are particularly adapted in several aspects to feeding on fungi ( Mycolaelaps ). Members of the largest genus of this family ( Proctolaelaps ) occupy various niches; some are also commonly found in flowers or on hummingbirds (presumably dispersing between flowers), but most are found in places where fungi are abundant, suggesting that they could be fungus feeders. Membranous lobes are observed in species of this genus presenting different feeding habits. Proctolaelalps bickleyi Bram and Proctolaelaps bulbosus Moraes, Reis & Gondim Jr. are examples of species that have membranous lobes, and under laboratory condition can feed on different substrates. According to Flechtmann (1976), the former species is able to develop and reproduce when feeding on fungus. Those species were shown to be able to develop and reproduce well offered an Eriophyidae mite or a fungus species as food sources, but not when offered pollen (Lawson-Balagbo et al., 2007; Galvão et al., 2011). Little is known about the feeding habits of members of the remaining genera of Melicharidae .

For the phytoseiids, the results of Flechtmann & McMurtry (1992) did not allow them to establish a relationship between food habits and cheliceral morphology. However, all of the species known to have a preference for pollen feeding ( Euseius species, type IV of McMurtry & Croft, 1997) evaluated in the study had large lobes. Other evaluated species belong to groups that have a predominantly predatory habit, although some of them could also feed on pollen (McMurtry & Croft, 1997), and these could have small to large lobes.

Based on the cheliceral structures, mainly dentition, Evans (1963) suggested Neocypholaelaps species to be pollen feeders, and Ameroseius , Epicriopsis and Brontispalaelaps species to be fungus feeders. Information provided in the original descriptions of species of these genera published since then corroborates Evans’ suggestion, indicating in addition that the flower inhabiting ameroseiids ( Afrocypholaelaps , Neocypholaelaps and Hattena ) can also feed on nectar. Haq (2001) claimed that N. stridulans could cause button fall in some coconut varieties, apparently by feeding on the tissues of coconut female flowers.

Mo (1971) reported N. indica to be unable to develop to adult when fed with glucose, but to develop and oviposit when fed with pollen (of undisclosed plant species). The same species was reported to develop and reproduce in Eucalyptus flowers (Ramanan & Ghai, 1984). Published information also suggests that Afrocypholaelaps and Hattena are pollen or nectar feeders. Under laboratory conditions, Seeman & Walter (1995) observed Afrocypholaelaps africana to be able to feed on sucrose solution and on pollen of Aegiceras corniculatum (L.) Blanco, leading the authors to conclude that the mites could also feed on nectar and pollen of that plant, on which they were naturally numerous. Seeman (1996) reported Hattena cometis Domrow and Hattena panopla Domrow to feed on nectar, pollen, sucrose solution and water under laboratory conditions.

The association between Ameroseius species and fungi under field condition has been extensively mentioned in the literature, although this has been confirmed for few species under controlled conditions. Flechtmann (1985) studied the biology of Ameroseius dendrovagans , showing its successful development and reproduction when fed with the fungus Trichoderma sp.. Moustafa & El-Hady (2006) reported Ameroseius (= Kleemania ) kosi (El-Badry, Nasr & Hafez) to be able to develop and reproduce on the fungi Sclerotium bataticola Taub. and Rhizoctonia solani Kühn.

Given that lobes are known to occur in flower inhabiting ameroseiids (probably pollen or nectar feeders) as well as in mites living in other habitats (probably mostly fungus feeders), the relevance of the lobes for each feeding habit is not immediately evident. Consistent explanations would require an examination of the morphology of lobes of different ameroseiid groups.

Evidence so far available leads to the following conclusions: (a) ameroseiid species that feed mainly on pollen (or nectar) have membranous cheliceral lobes (as also almost all melicharids and some phytoseiids); (b) ameroseiid species that apparently do not have pollen (or nectar) as the main food source may or may not have membranous lobes, but they do not have a setiform pilus dentilis [differently from melicharids, the vast majority of which has membranous lobes, and from phytoseiids, that seem to always have a setiform pilus dentilis, or at least its base, and often membranous lobes, that can be rudimentary].

Notes on ameroseiid ventral pore-like structures

Ameroseiids have the four pairs of lyrifissures usually found in most Mesostigmata on or next to the sternal, metasternal and genital shields (iv1 – iv3 and iv5). However, another pair of pore-like structures is observed in many, but not all ameroseiids, posterolaterad of the genital setae (st5) and anteriad of the genital lyrifissures (iv5). Authors often illustrate these structures but do not refer to them in the text. They have been interpreted by Moraes & Narita (2010) and Narita et al. (2011) as lyrifissures. However, their larger size and their different shape in comparison with iv5 observed in this paper and also in most of the papers in which they are shown suggest them to be pores, probably corresponding to the inguinal solenostome (SJ) of Athias-Henriot (1969) and to gv2 of Lindquist & Moraza (2009). Pores gv2 are often indistinctly located close to the posteromesad margin of coxae IV in many Mesostigmata (including some ameroseiids). In some other ameroseiids they are not evident, whereas in still others they seem to occupy a mesal position, next to the genital shield margin. The possibility that they could correspond to gv2 seems to be supported by their position in Ameroseius callosus Mašán and Ameroseius macrochelae Westerboer , closer to the internal margin of coxa IV than to the genital shield (Westerboer & Bernhard, 1963; Mašán, 1998).

In Neocypholaelaps , in addition to the species here described, the following species have been described as having gv2 mesally positioned: N. ampullula , N. apicola , N. breviperitremata , N. cocos , N. ceylonicus , N. favus Ishikawa, N. geonomae , N. hongkongensis , N. indica , N. leopoldi , N. nova, N. novaehollandiae , N. phooni , N. pradhani , N. stridulans and N. xylocopae . Nothing can be said in this regard for N. capitis , N. rotundus and N. varipilosa , given that the ventral surface or those species were not illustrated and that nothing was cited in the text of the descriptions or because pore-like structures were not shown in the original description. A mesal position for gv2 has also been illustrated in species of other ameroseiid genera, including Afrocypholaelaps (all but A. ranomafanaensis ), Ameroseius (several species), Brontispalaelaps ( B. marianneae ), Hattena [ H. ewae (Haitlinger) ], Epicriopsis ( E. langei Livshitz & Mitrofanov ), Sertitympanum ( S. exarmatum Elsen & Whitaker and S. mexicanum Villegas-Guzmán, Montiel-Parra, Vargas & Polaco ). Published information does not allow the determination of the position of this pore in Ameroseiella and Sinoseius . In our examination of some undetermined specimens of Ameroseius and in specimens that we have identified as Brontispalaelaps leveri , gv2 was discernible.

Thus, these observations indicate that the mesal position of gv2 is common in ameroseiids, that their position (or absence) in species of this family is of diagnostic interest and should be mentioned in the description of new ameroseiid species.

Figures

FIGURES 1 – 8. Neocypholaelaps kreiteri n. sp. female. 1. Chelicera; 2. Epistome; 3. Ventral view of gnatosoma; 4. Dorsum of idiosoma; 5. Venter of idiosoma; 6. Proximal section of peritreme and associated structures (a: unsclerotised cuticle; b: exopodal shield; c: peritrematic shield); 7. Part of spermathecal apparatus; 8. Pre-tarsus of leg I. Pores and lyrifissures enlarged to allow their differentiation.

FIGURES 9 – 12. Neocypholaelaps kreiteri n. sp. male. 9. Chelicera and spermatodactyl; 10. Dorsum of idiosoma; 11. Venter of idiosoma; 12. Dorsal view of femur, genu and tibia of leg IV. Pores and lyrifissures enlarged to allow their differentiation.

FIGURES 13 – 14. Neocypholaelaps kreiteri n. sp. deutonymph. 13. Dorsum of idiosoma; 14, Venter of idiosoma. Pores and lyrifissures enlarged to allow their differentiation.

FIGURES 15 – 18. Neocypholaelaps kreiteri n. sp. 15. Protonymph, dorsum of idiosoma; 16. Protonymph, venter of idiosoma; 17. Larva, dorsum of idiosoma; 18. Larva, venter of idiosoma. Pores and lyrifissures enlarged to allow their differentiation.

Tables

TABLE 1. Measurements (µm) of dorsal setae of each postembryonic stage of Neocypholaelaps kreiteri. n = number of specimens measured; (—) Absent.

Seta	Female n = 5	Male n = 5	Deutonymph n = 3	Protonymph n = 3	Larva n = 3
j1 j2	30 (27–35) 22 (19–23)	30 (22–37) 19 (16–22)	23 (18–27) 15 (14–15)	18 (17–19) 11 (9–12)	22 (22–23) —
j3	21 (19–22)	15 (12–16)	12 (11–13)	11 (10–12)	14 (13–15)
j4	21 (18–22)	13 (12–14)	11 (9–12)	9 (8–10)	11 (10–11)
j5	19 (18–20)	17 (15–18)	10 (9–11)	9 (8–9)	11 (10–11)
j6 z2 z4	22 (20–24) 21 (20–22) 20 (19–22)	12 (10–13) 16 (15–17) 14 (13–15)	10 (9–10) 13 (11–14) 13 (11–15)	9 (8–10) 11 (10–11) 10	15 (14–15) 13 (12–13) 14 (13–14)
z5	20 (17–21)	11 (10–12)	9 (7–11)	8 (7–8)	11 (10–11)
z6	23 (21–25)	13 (12–14)	10 (9–12)	—	—
s1	19 (18–20)	16 (14–18)	12 (10–14)	—	—
s2 s4 s5	19 (17–21) 27 (23–30) 28 (25–30)	16 (13–18) 47 (32–61) 49 (34–64)	12 (10–13) 20 (13–27) 22 (15–27)	— 12 (11–13) 11 (10–12)	— 14 —
s6	29 (27–30)	50 (30–70)	21 (14–27)	11 (10–12)	8 (7–9)
r2	24 (22–26)	50 (32–68)	21 (14–28)	11 (9–12)	—
r3	27 (24–30)	52 (34–70)	23 (17–29)	11 (10–11)	—
r4 r5 J2	27 (23–30) 28 (25–31) 23 (21–25)	48 (32–63) 52 (34–70) 13 (12–15)	14 (12–16) 20 (14–26) 11 (9–12)	— 11 (10–12) 8 (6–9)	— — —
J4 Z1	26 (24–28) 22 (21–23)	45 (26–64) 16 (15–16)	18 (11–24) 11 (9–12)	11 (9–12) 8 (6–9)	— —
Z2	27 (24–30)	42 (30–54)	19 (13–24)	9 (8–9)	8 (7–8)
Z4 Z5 S2	27 (24–30) 32 (30–35) 30 (27–33)	40 (30–49) 44 (33–55) 49 (35–63)	17 (10–23) 23 (16–29) 21 (13–28)	10 (9–11) 13 (11–14) 11 (9–12)	10 10 —
S3 S4	30 (26–34) 32 (29–34)	52 (37–67) 54 (36–72)	22 (13–31) 25 (15–32)	11 (10–12) 11 (10–12)	8 (7–8) 13 (12–13)
S5	34 (31–36)	57 (40–73)	24 (17–31)	11 (10–12)	13 (12–13)

TABLE 2. Measurements (µm) of ventral setae of each postembryonic stage of Neocypholaelaps kreiteri. n = number of specimens measured; (—) Absent.

Seta	Female n = 5	Male n = 5	Deutonymph n = 3	Protonymph n = 3	Larva n = 3
st1	27 (24–29)	23 (20–25)	19 (17–21)	17 (15–19)	15 (12–27)
st2	23 (22–25)	23 (20–25)	20 (19–21)	17 (15–19)	16 (15–17)
st3	24 (23–26)	23 (21–25)	22 (20–23)	15 (12–17)	15 (14–15)
st4	22 (19–24)	24 (21–27)	14 (11–17)	—	—
st5	24 (21–26)	24 (16–32)	17 (15–18)	—	—
Jv1	19 (18–20)	21 (18–24)	14 (13–15)	12 (10–13)	12 (10–14)
Jv2	16 (14–19)	22 (15–27)	14 (12–16)	10 (9–10)	11 (10–12)
Jv3	17 (15–19)	23 (15–30)	11 (9–13)	—	—
Jv4	32 (27–39)	44 (32–55)	16 (12–19)	—	—
Jv5	39 (35–42)	56 (42–70)	22 (15–27)	12 (11–12)	9 (7–10)
Zv2	18 (17–19)	24 (18–30)	13 (10–16)	9 (9–10)	8 (7–8)