Spadiseius spathiphyllae Lindquist & Moraza, 2008, new species
Creators: name: Lindquist, Evert E.
name: Moraza, Maria L.
Publisher: name: Zenodo
Year: 2008
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Mesostigmata
Ascidae
Spadiseius
Spadiseius spathiphyllae

description: Spadiseius spathiphyllae new species
(Figs. 7–9, 35–37, 39, 41–43, 45–67)
Diagnosis. All instars: legs with apical sclerotized rim of femur, genu, tibia clearly serrated ventrally. Adult: peritremes extending anteriorly only to level of marginal setae r2–r5, those of female thick; hypostomatic setae hyp4 shorter than hyp1–hyp2, but as long as hyp3. Adult female: marginal setae r2–r3 on edge of prodorsal shield, r4 on soft cuticle; subcapitulum without pair of gland-like structures between insertions of setae hyp1, and with setae hyp4 not swollen basally. Adult male: dorsal shield with setae in central region moderately short, blade-like, not inserted on warts, and with a variable number of peripheral setae of z–Z, s–S and r– R series forming a corona of slightly to clearly enlarged setae, either thickened and more or less capitate apically or attenuated; presternal area without platelets; peritrematal shield gland pore not enlarged at level between coxae II and III; spermatodactyl simple in form, sinuate, tapered apically; leg IV with a spur on basitarsus. Deutonymph: coxa IV seta subequally as long as setae on coxa III. Deutonymph and protonymph: legs I–IV with femoral seta ad-1 thicker and different in spatulate form than adjacent tapered setae. Protonymph: pygidial shield without hump or tubercle laterad seta S5. Larva: podonotal shield conspicuously rugose over much of surface; pygidial shield without puncta, with medial projection of anterior margin extending slightly beyond level of setal alveoli J2; legs I–III with femoral seta ad-1 rod-like, thicker, less tapered than adjacent setae.
Description. ADULT FEMALE. Dorsal shield 420–485 long, 230–275 at its greatest width at level of setae r3 (n = 6); shield wrinkled on vertex and conspicuously reticulate over entire surface (Fig. 46); podonotal region with longitudinal distance from alveoli of j1 to j5 subequal to that from j5 to j6. Peritrematal shields uniting with dorsal shield at level of setae s1; peritremes thick, extending to level of setae r2–r3. Body dorsum with approximately 56–58 pairs of setae, 11 or 12 of which (r4–r5, R1–R6, and 3 or 4 UR– setae) inserted on soft cuticle; dorsal shield with 4 or 5 extra pairs of setae amidst j, z and s series on podonotal region, and sometimes an extra pair of setae between S1 and Z1 and several paired or asymmetrically unpaired setae amidst J series on opisthonotal region. Dorsal setae uniform in simple but slightly curved, scimitar-like form (most of them slightly swollen at base) and moderately short length (15–21), S5 (25–28) Z5 (28–30) slightly largest, J5 clearly smallest (10–12). Anterodorsal expansions of exopodal plates above legs I formed as lineated, wrinkly plates (not illustrated, difficult to discern) touching vertex of dorsal shield.
Tritosternum with length of trapezoidal base (15–18) slightly shorter than basal width (24–27); laciniae free for about 0.6–0.7 of total length (60–70 excluding base). Presternal area weakly sclerotized, lineate, insensibly consolidated with sternal shield. Sternal shield (Fig. 47) faintly reticulated anteriorly, becoming more weakly sclerotized and unornamented (or desclerotized) posterior to level of second poroids; posterior margin faint, slightly concave; setae st1–st2 and first and second pairs of poroids inserted on sclerotized portion of shield, st3 inserted on desclerotized portion; st1–st3 slightly attenuated, similar in length (37–40), slightly longer than st4 (33) and st5 (33) on soft cuticle. Endopodal strips faintly formed alongside coxae III and IV. Genital shield smooth or faintly lineated, its lateral margins nearly straight or slightly concave alongside genital setae. Anal shield weakly reticulate-lineate, about as long as wide (72–75) at level of anterior edge of anus; postanal seta subequally as long as para-anal setae (17). Ten pairs of opisthogastric setae (JV1– JV5, ZV1–ZV5) plus 1 or 2 pairs of adjacent UR– setae on soft cuticle around anal shield, all similar in size (17–25) except for slightly thicker JV5, ZV4, ZV5 (22–25). Metapodal plates subdivided, larger piece slender, pointed anteriorly and posteriorly, about 23–32 long, 7–8 wide, smaller piece linear, difficult to discern. Spermathecal apparatus with thin, visibly dense, nearly straight conduit (section of major duct from embolus to apex of calyx, 30–35) leading from solenostome between bases of legs III and IV to a hyaline wrinkled sac (vesicle) (Figs. 48–49).
Tectum with anterior margin smooth, sharply pointed medially (Fig. 7). Fixed chela with 2 or 3 minute teeth beside offset tooth subapically (Fig. 50); movable chela (length 30–35) usually weakly bidentate, the more apical tooth hardly discernible, sometimes absent; antiaxial face of movable chela with sclerotized process along its basal half (Fig. 9 b); ventral mucro slender, attenuate, reaching mid-level of chela (Figs. 9 a, 50). Corniculi strongly convergent, sometimes overlapping apically (Fig. 59); internal malae slender, slightly longer than corniculi, their lateral margins finely fringed. Deutosternum with 7 or 8 transverse rows of denticles, evenly multidenticulate (7–12 denticles), none distinctly widened. Subcapitulum lacking gland-like structures between bases of anterior subcapitular setae; setae finely tapered, medial pair longest; capitular pair not noticeably thickened basally, shorter (22) than anterior (25–28) and medial (35–37) pairs. Subcapitulum with serrated ridge extending on either side laterally from bases of capitular setae (Fig. 59). Palptrochanter setae slender, subequal in length (16–18); palpgenu with seta al-2 tapered, similar in form to al- 1 in distinction to spatulate al of palpfemur; apical sclerotized rim of palpfemur and palpgenu serrated ventrally.
Legs IV the longest (415–440 excluding pretarsus) of legs, about as long as dorsal shield; other leg lengths: I 355–370, II 320–330, III 345–355. Tarsi II–IV with pair of apical setal processes (ad-1, pd-1) about one-third as long as length of pretarsi to base of claws. Leg II slightly thicker than legs III–IV, but thickness and form of its setae not differentiated from those of legs III–IV (as in Figs. 31–33). Coxae I with many serrated ridges on ventral face (Fig. 64), coxae II–IV with 2 or 3 lines on posteroventral faces, these serrated on II; seta on coxa IV about as long (25–34) as setae on coxa III. Apical sclerotized rim of femur, genu, tibia clearly serrated ventrally on legs I–IV (Fig. 64). Femora I–IV with dorsal seta ad-1 thickened, untapered, rodlike or slightly oar-like in contrast with adjacent simple setae, slightly longer from I (14–17) to IV (22–25) (much as in Figs. 30–33); legs without elongated macrosetae. Setation of genua and tibiae I–IV as presented for genus.
ADULT MALE. Dorsal shield 380–475 long, 265–350 at its greatest width at level of setae r5 (n = 10); podonotal region with longitudinal distance from alveoli of j1 to j5 subequal to that from j5 to j6; central and posterior area of shield with uniformly blade-like setae of mostly similar length, including some hypertrichy, on a given specimen but of variably short (15–25) to moderate length (25–40) among different specimens, and with a more or less well developed corona of a variable number of enlarged (lengths from 30 to 160) and either attenuated or apically capitate or oar-like setae peripherally (Figs. 51–53); setae j1 variably blade-like (14–15) or untapered (22–30) or attenuated (50–57); whether elongated or not, S1 consistently shorter (1/3–2/ 3) than adjacent setae s6 and S2 (Table 2). Dorsal shield entirely reticulated (not shown in figures), consistently without wart-like thickenings. Peritrematal shields uniting with dorsal shield at level between bases of legs II and III; peritrematal shield gland pore at that level not enlarged (Fig. 54); peritremes variable in thickness and length, extending to level of setae r5 or nearly to r2. Dorsal shield complement of setae, poroids and gland-pores similar to that in female, except marginals r5, R1–R2, R4–R6, poroid Rp and sometimes 1 or 2 UR setae usually on weakly sclerotized expanded margins of shield, though variably on soft cuticle; R3 sometimes absent.
Tritosternum much as in female, laciniae free for about 0.7 of total length (50–55 excluding base). Presternal area much as in female, without platelets (Fig. 58). Sternogenital shield smooth or ornamented with arched lines behind setae st5; of 4 or 5 pairs of setae on shield, st4 (35–55) longer than st1–st3 (20–30), st5 variably much longer (50–110) and often inserted near paragenital poroids (these hard to discern) on soft cuticle closely beside constricted posterolateral corners of shield; posterior margin of shield strongly delineated, nearly truncated, often bilobed (Figs. 56–58). Ventrianal shield unornamented, with weakly delineated anterior and often strongly sloping anterolateral margins; shield length (155–160) about 0.75 its greatest width (195–220) anteriorly where metapodal plates incorporated; anal region slightly more sclerotized, sometimes appearing delineated like an anal plate; ventrianal shield with circumanal setae and usually 7 pairs of opisthogastric setae (JV1–JV4, ZV1–ZV3), these setae similar in length as in female (15–25) or variably much more attenuated (40–90), JV3 often shorter than others; postanal seta (18–25) slightly longer than para-anal setae (15–20); JV5 and ZV4 variably short (15–30) to attenuated (105–115) not clavate distally, inserted on soft cuticle, ZV5 absent. Form of peritrematal and exopodal shields posteriorly as in female, except exopodal rims wider behind coxae IV.
Tectum with narrower base and more acutely pointed apex than in female. Cheliceral shaft narrowing dorsally at base of fixed digit (Fig. 55); fixed digit with a small offset tooth followed by 1–2 minute teeth at level of hyaline pilus dentilis, and with a large pointed tooth basally; spermatodactyl simple in form, extending sinuously antero-ventrally about 30 beyond apex of chela (Fig. 55). Corniculi more widely spaced basally than in female, their apices not overlapping; internal malae larger that in female, with fringed lateral margins and bifid apices (as in Fig. 26). Subcapitulum with rows of deutosternal denticles as in female. Subcapitulum with form and relative lengths of setae as in female, and with serrated ridge on either side of capitular setae and ventrally serrated apical sclerotized rim of palpfemur and palpgenu as in female. Palptrochanter setae subequal in length (15–20); palptibia with ventral seta av thicker, more spine-like than in female.
Relative leg lengths, excluding pretarsi, similar to those of female, I (350–420), II (295–385), III (345– 485), IV (395–620). Coxa IV seta at least as long (32–42) as coxa III setae (28–30). Coxal ornamention and serration of apically sclerotized rims of segments of legs I–IV as in female, but size and form of many setae variably polymorphic on femora, genua, tibiae and tarsi. Tarsi II–IV with pair of apical setal processes (ad-1, pd-1) as in female. Legs II–IV sometimes curved and slightly thicker relative to leg I than in female; tarsus II with setae av-1, av-2 modified to short, stout spines, and av-3 (mv) variably short setiform or spine-like (as in Fig. 28); basitarsus of legs IV and sometimes of III with conical spur posteroventrally beside seta pl-4 (Fig. 65). Femur I with dorsal seta ad-1 apically capitate or oar-like and variably longer (20–100) than in female; ad-1 on femora II–IV variably oar-like or attenuated, or apically capitate, and increasingly longer from II (20– 75) to IV (30–125). Legs I–IV with some dorsal and lateral setae variably oar-like or attenuated on femur of legs I–IV, genua II–IV and tibiae III–IV, and legs III–IV with some ventral and anterolateral setae variably attenuated (40 up to 75) on femur, genu, tibia and tarsus (Figs. 66, 67).
DEUTONYMPH. Dorsal shield 365–400 long, 200–270 wide at level of lateral incisions by setae s6 (n = 5); shield lightly evenly reticulate over nearly entire surface (Fig. 42); podonotal region with longitudinal distance from alveoli of j1 to j5 subequal to that from j5 to j6. Dorsal shield with approximately 35 to 40 pairs of setae: about 17–18 pairs (j1–j6, z2–z6, s3–s6, and 2 to 4 pairs of extra setae) on podonotal region, and 18 pairs (J1–J5, Z1–Z5, S1–S5, and a few paired or asymmetrically unpaired setae amidst J series) on opisthonotal region. Dorsal shield setae mostly alike in simple form (larger ones slightly swollen at base), mostly very short (5–7), similar in length to clunals J5; j1, s6, S2–S5 slightly longer (9–12), S4, S5 and Z5 barbed, Z5 largest (16–18), tapered or untapered. Dorsal setae on soft cuticle mostly 12–15 long, R1 longest (19–20). Peritremes extending anteriorly to level of setae s1; peritrematal shields extending further anteriorly but not uniting with dorsal shield.
Tritosternum similar in form to that in adult female. Sternal shield (Fig. 43) smooth, with narrowly rounded posterior margin; setae st4 (10–13) clearly shorter than st1–st3 (23–25). Anal shield unornamented, length (63–68) nearly equal to greatest width (65–75) at level of anterior edge of anus; postanal seta (13) slightly shorter than para-anal setae (15). Opisthogaster with 9 or 10 pairs of ventral setae (JV1–JV5, ZV1– ZV4) plus 1 or 2 adjacent UR– setae (ZV5 sometimes absent), most similarly short (5–10) but JV1–JV2 (15– 18), JV5 (17–20). Metapodal plates faint, oval (15 length, 8 width).
Tectum, chelicerae, most ventral gnathosomatic structures and palpi, including serrated apical sclerotized rim of palpfemur and palpgenu, similar to those in adult female, except corniculi less convergent, not overlapping apically.
Relative leg lengths, excluding pretarsi, similar to those of female, I (315–325), II (275–285), III (295– 300), IV (350–357). Coxal ornamentation, serration of apically sclerotized rims of segments, and form of legs I–IV and their setae as in adult female, except leg II no thicker than legs III–IV; tarsus I with pedestal bearing pretarsus less defined than on protonymph; tarsi II–IV tapered apically beyond insertions of av-1, pv-1. Coxa IV seta as long as coxa III setae (18–20). Dorsal seta ad-1 thicker, rod- or oar-like on femora I–III, much as on femur IV, in contrast with adjacent tapered setae, progressively slightly longer from I (12) to IV (18–19) (Fig. 45).
PROTONYMPH. Idiosoma 310–340 long, 210–255 wide at level of setae r5 (n = 5), with lightly sclerotized, fully reticulated podonotal and pygidial shields (Fig. 36); podonotal shield 200–202 long, 175–188 at widest level near posterior margin, with longitudinal distance from alveoli of j1 to j5 about 0.8 that from j5 to j6; pygidial shield 82–87 along midlength, 140–145 at widest level near seta S4, with anterior margin strongly protruding anteriorly slightly beyond level of bases of setae J2, and without protuberance near seta S5. Body dorsum with setae on mid-surfaces simple, very short, similar in length to clunals J5 (3–5), lateral and marginal setae slightly longer (10–13), S4–S5 (11–14), Z5 slightly longest (15), S4, S5, Z5 slightly barbed. Peritremes extending anteriorly nearly to level of anterior margins of coxae III.
Tritosternum similar in form to that in deutonymph and adult female, but base longer (15) relative to laciniae (40–45), which free for 0.7–0.8 of length. Sternal shield (as in Fig. 14) smooth; setae st5 inserted on soft cuticle much shorter (7) than st1–st3 (20–22); paragenital poroids absent. Anal shield unornamented, similar in form and structures to those on deutonymph (length 50–60, width 53–60), postanal seta (12) nearly as long as para-anal setae (11–14). Of opisthogastric setae on soft cuticle, JV2, ZV2 short (5–7), JV1, JV5 slightly larger (12).
Tectum more broadly irregularly triangular and bluntly pointed than in deutonymph; other gnathosomatic structures similar to those in deutonymph, except apical sclerotized rims of palpfemur and palpgenu less serrated and palpi with normal protonymphal complement of setae.
Leg lengths, excluding pretarsi, I (245–275), II (225–245), III (245–260), IV (260–280); pretarsi II–IV with apical setalike processes about one-fourth as long as length of pretarsi to base of claws. Form of legs and their setae, and patterns of serration on coxal faces and apical sclerotized rims of leg segments generally as in deutonymph, except tarsus I apically with more clearly defined pedestal (5) bearing pretarsus. Coxa IV seta as long as coxa III setae (15–16). Femora I–IV with dorsal seta ad-1 thicker and rod- or oar-like in contrast with adjacent tapered setae, and progressively slightly longer from I (10–11) to IV (13–15) (Fig. 41).
LARVA. Idiosoma 260–280 long, 175–180 wide at level of setae s4 (n = 2); podonotal shield rugose (Fig. 35), 190–205 long, 148–155 at widest level near posterior margin, with longitudinal distance from alveoli of j1 to j5 0.7–0.8 that from j5 to j6, and with lateral margins slightly concave between levels of setae z2 and z4 but not behind s4; pygidial shield with few lines, without puncta, about 65 along midlength in dorsal view (but further length of ca 15 folded under ventrally), 138–145 at widest level near anterior margin, with anterior margin projecting medially to level of setal alveoli J2 and deeply invaginated on either side of midline at level of setal alveoli J3 (Fig. 35), posterior margin also invaginated on either side of midline at level of setal alveoli J5. Dorsal body setae similarly short (8–10), simple on podonotal shield, s6, S3, S4 slightly shorter (6–8) on soft cuticle, Z3–Z4 on pygidial shield much larger (25–30) and thicker, capitate distally.
Tritosternum similar in form to that in protonymph, with laciniae free for about two-thirds of length (29– 37, excluding base). Sternal shield smooth (as in Fig. 11), with setae st1–st3 similar in length (20–22). Anal shield smooth, slightly wider (48–50) than long (45–47); para-anal setae (19–22) longer than postanal seta (12). Three or four pairs of short opisthogastric setae plus S5 and Z5 on soft cuticle, JV5 minute (3), JV2 longest (10–12), ZV2 sometimes absent.
Tectum with anterior margin bluntly unevenly triangular. Fixed digit of chelicera with dentition and pilus dentilis lobe as in protonymph; movable chela 17–18 long, edentate or with a minute tooth, and with ventral mucro (Fig. 37).
Leg lengths, excluding pretarsi: I (220–235), II (195–205), III (220–225); pretarsi II–III with apical setalike processes about one-third as long as length of pretarsi to base of claws. Form of legs and their setae, and patterns of serration on apical sclerotized rims ventrally on femora, genua, tibiae generally as in protonymph. Tarsus I apically with well defined pedestal (6) bearing pretarsus. Femora I–III with dorsal seta ad-1 similar in size (ca 15), thicker and untapered, rod- or oar-like, apically in contrast to adjacent femoral setae (Fig. 39).
Type material. COSTA RICA, Heredia Province, La Selva Biological Station, (10° 26' 1" N, 84° 1' 2" W) elevation 50–150 m: HOLOTYPE: adult female, Research Swamp, ex inflorescences of Araceae, Spathiphyllum friedrichsthallii, 10 February 1994, coll. S. Cunningham & E.E. Lindquist. PARATYPES: 18 adult females, 15 adult males, 8 deutonymphs, 12 protonymphs, 8 larvae, with same data as holotype; 3 adult females, 1 adult male, 1 deutonymph, Research Swamp, ex “flowers of Cantarrona aroid” (sic, Cantarrana Swamp, S. friedrichsthallii), 11 April 1991, coll. S. Cunningham; 7 adult females, Research Swamp, ex bee, Trigona silvestriana Vachal (on inflorescences of S. friedrichsthallii), 25 February, 8 March and 4 April 1994, coll. S. Cunningham; 1 adult male, “Puesto 15, 322g, 10m (10° 26' 0" N, 84° 1' 0" W)”, 3 March 1993.
Etymology. The specific epithet, spathiphyllae, is based on the name of the genus of aroid plants (Araceae) in whose inflorescences these mites undergo their life histories.
Remarks. Spathiphyllum friedrichsthallii is widespread in tropical lowland rainforest along the Caribbean coast, from southern Mexico to Colombia (Graysum 2003a). A sample of one fully developed inflorescence (spadix) of S. friedrichsthallii taken at the La Selva Biological Station, 10 Februrary 1994, by one of us (EEL) contained more than 300 mites, not accounting for eggs, including an abundance of all developmental instars and adults.
In males of this species, the presence of a basitarsal spur on leg IV may correlate with the strongly sclerotized, often bilobate ridge on the posterior edge of the sternogenital shield. The two structures may be in apposition in a grasping function while mating with females. We have observed similarly apposable structures among some fungus-inhabiting species of Lasioseius, e.g., L. muricatus (Koch) and L. tuberculiger (Berlese).
description: Published as part of Lindquist, Evert E. & Moraza, Maria L., 2008, A new genus of flower-dwelling melicharid mites (Acari: Mesostigmata: Ascoidea) phoretic on bats and insects in Costa Rica and Brazil, pp. 1-37 in Zootaxa 1685 on pages 22-32, DOI: 10.5281/zenodo.180479