Ptenothrix Börner, 1906
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https://doi.org/10.6620/ZS.2024.63-42 |
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https://treatment.plazi.org/id/03EF87E7-FFDC-FF80-6DB0-BF51FB0AFE2E |
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Felipe (2025-01-20 04:08:45, last updated 2025-01-20 14:34:33) |
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scientific name |
Ptenothrix Börner, 1906 |
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Genus Ptenothrix Börner, 1906 View in CoL
Genus diagnosis: Large abdomen without protuberance. Head, large abdomen anteriorly, and Abd VI with large spines (blunt acanthoid chaetae). Large abdomen posteriorly with longitudinal rows of short spines. Bothriotrichia A and D present on adults. Neosminthuroid chaetae missing on the parafurcal area. Dorsal valve of small abdomen dorsally with 5 chaetae arranged in two transverse rows; anterior with 3 chaetae and posterior with 2 robust, large and apically rounded chaetae (blunt acanthoid chaetae). Tibiotarsus III posteriorly with 2 (or rarely 3) modified serrated chaetae. Claws mostly without a tunica. Retinaculum with 4+4 teeth. Outer and inner dorsal chaetae of dens often serrated (based on Yosii and Lee 1963; Yosii 1970; Bretfeld 1999; Fjellberg 2007; Oliveira et al. 2020; Jo and Park 2023).
Type species: Podura atra Linnaeus, 1758 .
Ptenothrix taiwanensis sp. nov. ( Figs. 5A–C View Fig , 7–11 View Fig View Fig View Fig View Fig View Fig , 12A, 12C View Fig , 13 View Fig , Table 2) urn:lsid:zoobank.org:act:DC999C0A-A464-458B-99F0-0E65B70FD2CB
Ptenothrix denticulata ( Folsom, 1899) View in CoL : Cheng et al. 2022, p. 137 –138 (text-fig. 4A).
Type material: TAIWAN: Holotype ñ on slide: Taiwan, New Taipei City, Xindian Dist., Changfu Temple (24.91491, 121.53243), 7, May. 2022. by searching rotten wood, HJ Cheng, DY Cheng, JK Cheng leg. ( NTUE13100001 ). 4 paratypes on slides: 3ñ 1ò, same data as holotype (1ñ 1ò in NTUE: ñ NTUE13100002 , ò NTUE13100003 ; 2ñ in NMNS: 8848-1, 8848-2). 3 paratypes in ethanol: 2ñ 1 sex undetermined (DNA voucher), same data as holotype (1ñ 1 sex undetermined in NTUE: ñ NTUE13100004 , sex undetermined NTUE13100005 ; 1ñ in NMNS: 8848-3). GoogleMaps
Other analyzed slide specimens: TAIWAN: 1ñ, Keelung City, Anle Dist., Lover’s Lake Park (25.159123, 121.704894), 23. September. 2022, by searching rotten wood, leg. HJ Cheng, ZJ Chang ( NTUE 13300001); 1ñ, Yilan County, Datong Township (24.619015, 121.679917), 1. October. 2022, by beating vegetation, leg. HJ Cheng, ML Fu ( NMNS: 8848-4); 2ò, Pingtung County, Manzhou Township, 31. June to 4. July. 2009, leg. ML Jeng ( NMNS: 8848-5, 8848-6); 3ñ 1ò, Hualien County, Da Nong Da Fu Forest Park, 18. November to 12. December. 2018, flight interception trap, leg. YH Ho ( NMNS: ñ 8848-7, ñ 8848-8, ñ 8848-9, ò 8848-10); 1ñ 3ò, Tainan City, Dongshan Dist., Shihe Mountain, 27. August to 7. October. 2021, Malaise trap, leg. ML Jeng, YH Ho, WT Yang ( NMNS: ñ 8848-11, ò 8848-12, ò 8848-13, ò 8848- 14); 2ñ 1ò New Taipei City, Fushan Botanical Garden (24.7634, 121.5849), 14. September to 2. October. 2021, flight interception trap, leg. YH Ho, CT Hsu ( NMNS: ñ 8848-15, ñ 8848-16, ò 8848-17); 1ñ, Hsinchu County, Syakaro National Trail, 18. May. 2022, leg. LH Chen ( NTUE 13300002).
Etymology: The name taiwanensis , an adjective meaning “Taiwanese”, is given to this species with reference to its type locality, Taiwan.
Diagnosis: Head vertex with a median longitudinal stripe of dark pigment between the eyes, each eyepatch with a posterior dark spot ( Fig. 5A, C View Fig ), dorsal large abdomen with a posterior dark spot, small abdomen without any large spot of pigment ( Fig. 5A View Fig ). Ant II with 3 ( Fig. 7B View Fig ), Ant III with 10 cup sensilla, distal Ant III partially divided into about 8 pseudo-subsegments ( Fig. 7C View Fig ), Ant IV with 4 subsegments ( Fig. 7D View Fig ). Head frontal area with 6+6 spines, D line central spines shorter than the lateral ones, clypeal area with 2 large blunt unpaired central acanthoid chaetae and 2 less thick midfacial unpaired chaetae, b, c, e and f lines with 2 cup sensilla each ( Fig. 8A View Fig ). Large abdomen anterior Th. II m line with 1+1 or 2+2 large blunt acanthoid chaetae, dorso-posterior region with 4 longitudinal lines of short spines, with 6, 5, 14, 14 spines from the more lateral to the more dorsal line, respectively ( Fig. 9A View Fig ). Parafurcal area with two cup sensilla, without any serrated chaetae. Dorsal anal valve of small abdomen with as1–2, ms2, ms4 and mps4 as blunt acanthoid chaetae in both sexes; ventral anal valve aai1 of the female and mi1 of both sexes as blunt acanthoid chaetae, 3 chaetae between aai1 and ai 6 in males and females; female subanal appendage smooth, blunt and thick ( Fig. 9B, C View Fig ). Tibiotarsus III with 2 modified serrated chaetae, 1 microsensillum in a cavity (oval organ), 5 cup sensilla, and 4 oval organs (without inner sensilla) ( Fig. 10F View Fig ). Ungues with pseudonychia and lacking tunica, with 2 dorsal, 2 internal and 2+2 lateral teeth each, unguiculi with one internal tooth each, apical filaments acuminate or slightly knobbed, surpassing the ungues tip on all legs ( Fig. 11A–C View Fig ). Manubrium with 8–10 dorsal chaetae on each side. Dens dorsally (posteriorly) with 24 chaetae, 15 of them feathered ( Fig. 11F View Fig ), dens ventral (anterior) formula from the apex to the basis: 3, 2, 1, 1… 1 ( Fig. 11G View Fig ).
Description: Average body (head + trunk) length of type series: 2.4 mm in females and 1.77 mm in males, holotype with 2.3 mm. Habitus typical of the genus. Body and appendages with different types of chaetae as presented in figure 4. Specimens in ethanol with background color white to pale yellow, with mottled brown symmetrical longitudinal stripes upon the anterior 4/5 of the dorsum, connected by a stripe and scattered around lateral sides of the body. A dark almost square patch on the bulge of the dorso-posterior large abdomen, small abdomen without any large spot of pigment, head with irregular patterns of pigment, vertex with a longitudinal stripe of dark pigment between eyes, each eyepatch with a posterior dark spot. Ant I red-purple, Ant II basally pale red, apically dark purple, Ant III–IV dark purple. Legs yellowish, banded with three purple stripes on tibiotarsus. Furca pale ( Fig. 5A, B View Fig ). Most body chaetae smooth (not denticulate).
Head ( Figs. 7–8 View Fig View Fig ): Antennae shorter than body, 1.7 mm in holotype. Holotype antennal segment ratio of Ant I:II:III:IV as 1:6.26:8.28:1.57. Ant I with 7 regular chaetae, two of them ventral ( Fig. 7A View Fig ), Ant II with 20 regular chaetae plus 3 cup sensilla ( Fig. 7B View Fig ), Ant III distally partially divided into about 8 distal pseudo-subsegments, with 80 regular chaetae, 10 cup sensilla and 1 microsensillum, apical organ typical, with 2 sense rods inside a single shallow invagination ( Fig. 7C View Fig ), Ant IV with 4 subsegments and about 61 regular chaetae ( Fig. 7D View Fig ). Head length (along the longitudinal aspect of the body) 306.81 µm in a female paratype (holotype unclear due to position), head height (from mouth to vertex) 560 µm in holotype. Eyes 8+8 with black pigment ( Fig. 13G View Fig ), eyepatches with 2 interocular spine-like chaetae, the internal larger than the external ( Fig. 8A View Fig ). Head frontal area with only A, D, E lines, with 2/3/1 spines, respectively (6+6 spines in total), D line central spines shorter than the lateral ones ( Fig. 12A View Fig ). Interantennal area α, β and γ lines with 2/2/1 short chaetae, respectively; clypeal area a– f lines (dorsal and ventral areas combined) in most specimens with 8(+1)/8(+1)/5/4/4(+1)/5(+1) chaetae respectively; b, c, e and f lines with 2 cup sensilla each; few specimens with chaetae a1, b1 or e1 absent or with extra chaetae between c and b lines ( Fig. 8A View Fig ). Distal margin of the clypeus with 3 prelabral chaetae, chaetotaxy of labral with 2(+1) p, 2(+1) m + 2 a chaetae, a2 thicker than the others, p0 and p1 chaetae reduced; labrum without clearly formed papillae ( Fig. 8B View Fig ). Mandibles asymmetrical with 4–6 apical incisive teeth (left with 4–6 teeth, right with 4 teeth) ( Fig. 8C View Fig ); maxilla capitulum globular, with 6 lamellae, 3 smooth and 3 fringed, without any clear modification ( Fig. 8D View Fig ); Labial papilla E with 4 guard chaetae, lateral process finger-shaped, almost reaching the apex of the papilla ( Fig. 8E View Fig ); details of other labial papillae not clearly observable. Maxillary outer lobe with 2 chaetae subequal in length, apical one thicker than the basal one, sublobal plate with 2 chaetae-like appendages ( Fig. 8F View Fig ). Ventral groove with 1 and 1 surrounding chaetae from lines a and b, respectively, labium basal fields with 4 central (a2 longer than the others) and 5 lateral chaetae ( Fig. 8G View Fig ).
Trunk (large and small abdomens) ( Fig. 9 View Fig ): Trunk length of the holotype 1.54 mm. Large abdomen ( Fig. 9A View Fig ): thorax continuous with abdomen, without any visible segmentation or constrictions. Chaetotaxy similar between males and females, Th II with 1 a and 3 to 4 m chaetae, 1+1 or 2+2 of them as large blunt acanthoid chaetae; Th III with 1 a and 3 m chaetae; Abd I with 3 a chaetae; bothriotricha A ( Fig. 13A View Fig ), B, C present and misaligned, A posteriorly to B–C and on a large papilla with a surrounding cup sensillum, B and C with 4 surrounding chaetae between them, each inside a small papilla; dorso-posterior region with 4 longitudinal lines of spine-like chaetae, with 6/5/14/14 chaetae for the more lateral to the more dorsal line, respectively. Parafurcal area (furca basis) without neosminthuroid chaetae, with 2 cup sensilla, 2 large blunt acanthoid chaetae and 6 to 7 regular chaetae. Bothriothricum D in the large abdomen, in a small papilla. Small abdomen of the female ( Fig. 9B View Fig ): dorsal anal valve with as1–5, ms1–4, mps1–4, mps’ and ps1–2 chaetae, as1, ms1 and ps1 unpaired; as4–5 as cup sensilla, as1–2, ms2, ms4 and mps4 as blunt acanthoid chaetae, ms3 as a S chaeta; ventral anal valves each with aai1, ai1–6, ami1–2, mi1– 5, mpi1–2 and pi1–3 chaetae, ami2 as an oval organ; ai1 as a cup sensillum, ai2–3 as S chaetae, aai1 and mi1 as a blunt acanthoid chaetae, mi5 as the subanal appendage, smooth, blunt and thick. Another interpretation of the small abdomen chaetotaxy following Yosii and Lee (1963) in fig. 9C. Genital plate of the female lacking dorsal chaetae, ventral area with 7 to 9 chaetae on each side ( Fig. 9D View Fig ). Small abdomen of male ( Fig. 9E View Fig ): dorsal anal valve with as1–5, ms1–4, mps1, mps4, mps’ (present or absent), and ps1–2 chaetae, as1, ms1, ps1 unpaired, as4–5 as cup sensilla, as1–2, ms2, ms4, mps4 as blunt acanthoid chaetae, ms3 as a S chaeta; ventral anal valves each with aai1, ai1–6, ami1–2, mi1–5 and pi1–3 chaetae, ai1 as a cup sensillum, ai2–3 as S chaetae, ami2 as an oval organ, mi1 as a blunt acanthoid chaeta; 3 chaetae between aai1 and ai 6 in males ( Figs 9B, E View Fig and 12C View Fig ) and females. Another interpretation of the small abdomen chaetotaxy following Yosii & Lee (1963) in fig. 9F. Genital plate of male densely covered by chaetae, number unclear.
Large abdomen appendages ( Figs. 9A View Fig , 10 View Fig , 11 View Fig ): Epicoxa, subcoxa and coxa I with 0, 1, 0 chaetae, respectively ( Fig. 9A View Fig ); trochanter I with 4 regular chaetae; femur I with 12 regular chaetae plus 1 microsensillum in a cavity (oval organ) ( Fig. 13E View Fig ) and 1 cup sensillum ( Figs. 10A View Fig , 13B View Fig ); tibiotarsus I with 40 regular chaetae plus 1 microsensillum in a cavity (oval organ), 3 cup sensilla and 4 oval organs ( Fig. 13D View Fig , without inner sensilla), distal whorl with 8 chaetae ( Fig. 10B View Fig ). Epicoxa, subcoxa and coxa II with 1, 1, 3 chaetae, respectively ( Fig. 9A View Fig ); trochanter II with 5 regular chaetae; femur II with 14 regular chaetae plus 1 microsensillum in a cavity (oval organ) and 1 cup sensillum ( Fig. 10C View Fig ); tibiotarsus II with 41 regular chaetae plus 1 microsensillum in a cavity (oval organ), 3 cup sensilla and 4 oval organs (without inner sensilla), distal whorl with 9 chaetae ( Fig. 10D View Fig ). Epicoxa, subcoxa and coxa III with 1, 1, 5 chaetae (including one apical small acanthoid chaetae), respectively ( Fig. 9A View Fig ); trochanter III with 6 regular chaetae; femur III with 14 regular chaetae plus 1 microsensillum in a cavity (oval organ) and 1 cup sensillum ( Fig. 10E View Fig ); tibiotarsus III with 37 regular chaetae plus 2 modified serrated chaetae ( Fig. 13F View Fig ), 1 microsensillum in a cavity (oval organ), 5 cup sensillum, and 4 oval organs (without inner sensilla), distal whorl with 9 chaetae ( Fig. 10F View Fig ), number of teeth on modified serrated chaetae variable, from 4 to 7. Tibiotarsus I with an apical sinusoid chaeta bending across the unguiculus. Inner apical macrochaeta spiky in tibiotarsus I ( Fig. 10B View Fig ), and blunt in tibiotarsi II – III ( Fig. 10D, F View Fig ). Foot complexes I–III with 2 small pretarsal chaetae each, 1 anterior and 1 posterior; ungues with 2 unpaired inner teeth subequal in size, lateral lamellae with 2+2 teeth ( Fig. 13K View Fig , some specimens with an extra basal smaller tooth in the fore and mid legs), pseudonychia present ( Fig. 13L View Fig ), merged to the dorsal face with 2 unpaired dorsal teeth, the proximal one smaller, with lateral margins irregularly serrate. Unguiculi with 1 basal tooth and 1 axial filament surpassing the tip of the ungues, apical filaments acuminate or slightly knobbed ( Fig. 11A – C View Fig ). Collophore with 1+1 chaetae on corpus plus 1+1 distal chaetae on lateral flaps, with a pair of long and warty sacs as typically seen in Dicyrtomidae ( Fig. 13H, I View Fig ). Tenaculum typically with a quadridentate ramus, corpus with 4 apical chaetae ( Fig. 13J View Fig ). Furcal size length in holotype as manubrium = 168.48 µm; dens = 556.21 µm; and mucro = 176.94 µm. Manubrium with 8 to 10 dorsal (posterior) chaetae on each side ( Fig. 11E View Fig ); dens dorsally (posteriorly) with 24 chaetae: 10 on the dorso-external (E1–10), 10 on the dorso-internal (J1–10) and 4 dorso-central ( PE 1–4) chaetae, respectively, external and internal chaetae feathered ( Fig. 13C View Fig ), except for the chaetae near the manubrium and an apical-external one ( Fig. 11F View Fig ); dens ventrally (anteriorly) with 8 chaetae, with the following formula from the apex to the basis: 3, 2, 1, 1… 1 ( Fig. 11G View Fig ); mucro with a narrow apex, with both edges serrated, with about 33 (inner) and 28 (outer) serrations on each edge, with an apical notch ( Fig. 11H View Fig ). Ratio mucro: dens: manubrium in holotype 1: 3.3: 1.05.
Distribution: Low elevation of Taiwan (mainly the northern and central region), and one locality in Nangan Island, Matsu (public toilet of Mt. Yuntai).
Habitat: Most Dicyrtomidae , including Ptenothrix taiwanensis sp. nov. are atmobiotic ( Bretfeld 1999). Specimens of the new species generally inhabit wet rotten wood and dead leaves of tree ferns and Miscanthus bushes. Some specimens were also found associated with the leaf litter layer, especially juveniles. Sampling localities of Ptenothrix taiwanensis sp. nov. are presented as orange dots in figure 1.
Remarks: Ptenothrix taiwanensis sp. nov. specimens were identified as Ptenothrix denticulata ( Folsom, 1899) in Cheng et al. (2022), which is now proven to be a misidentification (see Fig. 6 View Fig and Table 2). Ptenothrix taiwanensis sp. nov. is remarkably similar to Ptenothrix matsuensis sp. nov., described in the next section. We consider both to be cryptic species due to their strong resemblance in color pattern and overall chaetotaxy. In addition to Taiwan Island, P. taiwanensis was also collected on the tile wall in a public toilet in Nangan Island in Matsu, but was not found in any other localities in Matsu. This made us presume that the record in Matsu could be due to recent human intervention.
Compared with other Ptenothrix species found in the vicinities specimen collection, such as Taiwan and South China, Japan, and the type locality of P. denticulata ( Table 2), the two new species differ from the others by: frontal head A internal spines as long as lateral ones (shorter than the lateral ones in P. denticulata ( Folsom, 1899) and longer in P. denticulata catenata Börner, 1909 , P. corynophora Börner, 1909 P. gigantisetae Lin & Xia, 1985 , and P. huangshanensis Chen & Christiansen, 1996 ), Ant IV with 4 subdivisions (2–4 in P. denticulata , 2–3 in P. corynophora , 5 in P. huangshanensis , and 7 in P. gaoligonshanensis Itoh & Zhao, 2000 ), and dorsal dens with 10 inner chaetae (9 in P. annulatus , P. dinghuensis , P. gigantisetae , P. palmisetacea , and P. sinensis ). Further comparisons are listed in table 2.
Ptenothrix matsuensis sp. nov. ( Figs. 5D–F View Fig , 12B,12D View Fig , 14 View Fig , Table 2) urn:lsid:zoobank.org:act:B784F1E5-234C-4B42-8F29-F6B96A9AE17A
Type materials: TAIWAN: Holotype ñ on slide, Lienchiang County, Nangan Township, Shengtian Park (26.154204, 119.916068), 25. May. 2023, by beating vegetation, leg. HJ Cheng, YH Ho ( NTUE13100006 ). 4 paratypes on slides: 2ñ 2ò, same data as holotype (1ò 1ñ in NTUE: ò NTUE13100008 , ñ NTUE13100007 , 1ò 1ñ in NMNS: ò 8848- 18, ñ 8848-19). 2 paratypes in ethanol: 1ò 1 sex undetermined (DNA voucher), Lienchiang County, Nangan Township , Motianling (Skyscraper Ridge) Trail (26.161192, 119.953177), 25. May. 2023, by beating vegetation, leg. HJ Cheng, YH Ho (1ò 1 sex undetermined in NTUE: ò NTUE13100009 , sex undetermined NTUE13100010 ). GoogleMaps
Other analyzed slide specimens: TAIWAN: 3ñ on slide, Lienchiang County, Nangan Township, Siwei Rd. (26.173417, 119.917225), 25. May. 2023, leg. HJ Cheng, YH Ho (2 in NTUE: NTUE 13300003 and NTUE 13300004; 1 in NMNS: 8848-20). 3ò on slide, Lienchiang County, Nangan Township, Motianling (Skyscraper Ridge Trail) (26.161192, 119.953177), 25. May. 2023, leg. HJ Cheng, YH Ho (1 in NTUE: NTUE 13300005; 2 in NMNS: 8848-21, 8848-22).
Etymology: The new species was named after its type locality, Matsu Islands.
Diagnosis: Head vertex without a longitudinal stripe of dark pigment between eyes, each eyepatch with a posterior dark spot ( Fig. 5D View Fig ), dorsal large abdomen lacking any dark spot, dorsal small abdomen almost entirely covered by a large patch of dark pigment ( Fig 5D View Fig ). Ant II with 3, Ant III with 10 cup sensilla, distal Ant III partially divided into about 8 pseudo-subsegments, Ant IV with 4 subsegments. Head frontal area with 6+6 spines, D line central spines as long as the lateral ones ( Figs. 12B View Fig , 14A View Fig ), clypeal area with 2 large blunt unpaired central acanthoid chaetae and 2 less thick midfacial unpaired chaetae, b, c, e and f lines with 2 cup sensilla each. Large abdomen Th. II anterior m line with 1+1 large blunt acanthoid chaetae, dorso-posterior region with 4 longitudinal lines of short spines, with 5–6/ 5/ 12–14/ 12–14 spines from the more lateral to the more dorsal line, respectively ( Fig. 14B View Fig ). Parafurcal area with two cup sensilla, without any serrated chaetae. Dorsal anal valve of small abdomen with as1–2, ms2, ms4 and mps4 as blunt acanthoid chaetae in both sexes; ventral anal valve aai1 of the female and mi1 of both sexes as a blunt acanthoid chaetae, 3 chaetae between aai1 and ai 6 in females, only 2 in males ( Figs. 12D View Fig , 14C View Fig ); female subanal appendage smooth, blunt and thick. Tibiotarsus III with 2 modified serrated chaetae, 1 microsensillum in a cavity (oval organ), 5 cup sensilla, and 4 oval organs (without inner sensilla) (as in Fig. 10F View Fig ). Ungues with pseudonychia and lacking tunica, with 2 dorsal, 2 internal and 2+2 lateral teeth each, unguiculi with one internal tooth each, apical filaments acuminate or slightly knobbed, surpassing the ungues tip in all legs (as in Fig. 10A – C View Fig ). Manubrium with 7 dorsal chaetae on each side ( Fig. 14D View Fig ). Dens dorsally (posteriorly) with 24 chaetae, 15 of them feathered (as in Fig. 11F View Fig ), dens ventral (anterior) formula from the apex to the basis: 3, 2, 1, 1… 1 (as in Fig. 11G View Fig ).
Description: Average body (head + trunk) length of type series: 1.82 mm in females and 1.38 mm in males, holotype with 1.9 mm. Habitus typical of the genus. Overall chaetotaxy similar to Ptenothrix taiwanensis sp. nov. Head vertex without a longitudinal stripe of dark pigment between eyes, each eyepatch with a posterior dark spot ( Fig. 5D View Fig ), dorsal large abdomen lacking any dark spot, dorsal small abdomen almost entirely covered by a large patch of dark pigment. Ant I red-purple, Ant II basally pale red, apically dark purple, Ant III–IV dark purple. Legs yellowish, banded with three purple stripes on tibiotarsus. Furca pale. Most body chaetae smooth (not denticulate).
Head: Antennae shorter than body, 1.27 mm in holotype. Holotype antennal segments ratio of Ant I:II:III:IV as 1:6.73:7.7:1.8. Antennal chaetotaxy as in Ptenothrix taiwanensis sp. nov., with no observable differences between the two species, Ant I with 7 regular chaetae, two of them ventral (as in Fig. 7A View Fig ), Ant II with 20 regular chaetae plus 3 cup sensilla (as in Fig. 7B View Fig ), Ant III distally partially divided into about 8 distal pseudo-subsegments, with 80 regular chaetae, 10 cup sensilla and 1 microsensillum, apical organ typical, with 2 sense rods inside a single shallow invagination (as in Fig. 7C View Fig ), Ant IV with 4 subsegments and about 61 regular chaetae (as in Fig. 7D View Fig ). Head length (along the longitudinal of the body) 243.5 µm in a female paratype (holotype unclear due to position), head height (from mouth to vertex) 613.97 µm in holotype. Head chaetotaxy mostly similar to Ptenothrix taiwanensis sp. nov. Eyes 8+8 with black pigment, eyepatches with 2 interocular spine-like chaetae, the internal larger than the external one ( Fig. 14A View Fig ). Head frontal area with only A, D, E lines, with 2/3/1 spines, respectively (6+6 spines in total), D line central spines sharp and as long as the lateral ones ( Figs. 12B View Fig , 14A View Fig ). Interantennal area α, β and γ lines with 2/2/1 short chaetae, respectively (as in Fig. 8A View Fig ); clypeal area a–f lines (dorsal and ventral areas combined) with 8(+1)/8(+1)/5/4/4(+1)/5(+1) chaetae respectively; b, c, e and f lines with 2 cup sensilla each. Distal margin of the clypeus with 3 prelabral chaetae, chaetotaxy of labral with 2(+1) p, 2(+1) m + 2 a chaetae, a2 thicker than the others, p0 and p1 chaetae reduced; labrum without clear formed papillae (as in Fig. 8B View Fig ). Mandibles asymmetrical with 4–6 apical incisive teeth (left with 6 teeth, right with 4 teeth); maxilla capitulum globular, with 6 lamellae, 3 smooth and 3 fringed, without any clear modification (as in Fig. 8C and D View Fig ). Labial papilla E with 4 guard chaetae, lateral process finger-shaped, almost reaching the apex of the papilla (as in Fig. 8E View Fig ). Maxillary outer lobe with 2 chaetae subequal in length, apical one thicker than the basal one, sublobal plate with 2 chaetae-like appendages (as in Fig. 8F View Fig ). Ventral groove with 1 and 1 surrounding chaetae from lines a and b, respectively, labium basal fields with 4 central (a2 longer than the others) and 5 lateral chaetae (as in Fig. 8G View Fig ).
Trunk (large and small abdomens): Trunk length of holotype 1.31 mm. Large abdomen: thorax continuous with abdomen, without any visible segmentation or constrictions. Chaetotaxy similar between males and females, and almost identical to Ptenothrix taiwanensis sp. nov. Th II with 1 a and 3 to 4 m chaetae, none as large blunt acanthoid chaetae; Th III with 1 a and 3 m chaetae; Abd I with 3 a chaetae; bothriotricha A, B, C present and misaligned, A posteriorly to B–C and on a large papilla with a surrounding cup sensillum, B and C with 4 surrounding chaetae between them, each inside a small papilla; dorso-posterior region with 4 longitudinal lines of spine-like chaetae, with about 5–6/5/12–14/12– 14 chaetae for the more lateral to the more dorsal line, respectively ( Fig. 14B View Fig ). Parafurcal area (furca basis) without neosminthuroid chaetae, with 2 cup sensilla, 2 large blunt chaetae and 7 regular chaetae. Bothriothricum D in the large abdomen, in a small papilla (as in Fig. 9A View Fig ). Small abdomen of the female: dorsal anal valve with as1–5, ms1–4, mps1–4, mps’ and ps1–2 chaetae, as1, ms1 and ps1 unpaired; as4–5 as cup sensilla, as1–2, ms2, ms4 and mps4 as blunt acanthoid chaetae, ms3 as a S chaeta; ventral anal valves each with aai1, ai1–6, ami1–2, mi1–5, mpi1–2 and pi1–3 chaetae, ami2 as an oval organ; ai1 as a cup sensillum, ai2–3 as S chaetae, aai1 and mi1 as a blunt acanthoid chaetae, mi5 as the subanal appendage, smooth, blunt and thick; 3 chaetae present between aai1 and ai6 (as in Fig. 9B View Fig ). Small abdomen of male: dorsal anal valve with as1–5, ms1–4, mps1, mps4, mps’, and ps1–2 chaetae, as1, ms1, ps1 unpaired, as4–5 as cup sensilla, as1–2, ms2, ms4, mps4 as blunt acanthoid chaetae, ms3 as S chaeta; ventral anal valves each with aai1, ai1–6, ami1–2, mi1– 5 and pi1–3 chaetae, ai1 as a cup sensillum, ai2–3 as S chaetae, ami2 as an oval organ, mi1 as a blunt acanthoid chaeta; 2 chaetae present between aai1 and ai6 ( Figs. 12D View Fig , 14C View Fig ). Genital plates of female and male unclear.
Large abdomen appendages: overall chaetotaxy of legs, ventral tube, tenaculum and furca as described to Ptenothrix taiwanensis sp. nov. Epicoxa, subcoxa and coxa I with 0, 0, 1 chaeta, respectively; trochanter I with 4 regular chaetae (as in Fig. 9A View Fig ); femur I with 12 regular chaetae plus 1 microsensillum in a cavity (oval organ) and 1 cup sensillum (as in Fig. 10A View Fig ); tibiotarsus I with 40 regular chaetae plus 1 microsensillum in a cavity (oval organ), 3 cup sensilla and 4 oval organs (without inner sensilla), distal whorl with 8 chaetae (as in Fig. 10B View Fig ). Epicoxa, subcoxa and coxa II with 1, 1, 3 chaetae, respectively (as in Fig. 9A View Fig ); trochanter II with 5 regular chaetae; femur II with 14 regular chaetae plus 1 microsensillum in a cavity (oval organ) and 1 cup sensillum (as in Fig. 10C View Fig ); tibiotarsus II with 41 regular chaetae plus 1 microsensillum in a cavity (oval organ), 3 cup sensilla and 4 oval organs (without inner sensilla), distal whorl with 9 chaetae (as in Fig. 10D View Fig ). Epicoxa, subcoxa and coxa III with 1, 1, 5 chaetae (including one apical small acanthoid chaetae), respectively (as in Fig. 9A View Fig ); trochanter III with 6 regular chaetae; femur III with 14 regular chaetae plus 1 microsensillum in a cavity (oval organ) and 1 cup sensillum (as in Fig. 10E View Fig ); tibiotarsus III with 37 regular chaetae plus 2 modified serrated chaetae, 1 microsensillum in a cavity (oval organ), 5cup sensillum, and 4 oval organs (without inner sensilla), distal whorl with 9 chaetae, number of teeth on modified serrated chaetae variable, from 4 to 7 (as in Fig. 10F View Fig ). Tibiotarsus I lacking any apical bent sinusoid chaeta. Inner apical macrochaeta spiky in tibiotarsus I and blunt in tibiotarsi II – III (as in Fig. 10B, D and F View Fig ). Foot complexes I – III similar to Ptenothrix taiwanensis sp. nov., with 2 small pretarsal chaetae each, 1 anterior and 1 posterior; ungues with 2 unpaired inner teeth subequal in size, lateral lamellae with 2+2 teeth, duplicate teeth not seen, pseudonychia present, merged to the dorsal face with 2 unpaired dorsal teeth, the proximal one smaller, with lateral margins irregularly serrate. Unguiculi with 1 basal tooth and 1 axial filament surpassing the tip of the ungues, apical filaments acuminate or slightly knobbed (as in Fig. 11A–C View Fig ). Collophore with 1+1 chaetae on corpus plus 1+1 distal chaetae on lateral flaps (as in Fig. 11D View Fig ), with a pair of long and warty sacs. Tenaculum with a quadridentate ramus, corpus with 4 apical chaetae. Furcal size length in holotype as manubrium = 153.62 µm; dens = 421.74 µm; and mucro = 149.07 µm. Manubrium with 7 dorsal (posterior) chaetae on each side ( Fig. 14D View Fig ); dens dorsally (posteriorly) with 24 chaetae: 10 on the dorso-external (E1–10), 10 on the dorso-internal (J1–10) and 4 dorso-central ( PE 1–4) chaetae, respectively, external and internal chaetae feathered, except for the chaetae near the manubrium and an apical-external one (as in Fig. 11F View Fig ); dens ventrally (anteriorly) with 8 chaetae, with the following formula from the apex to the basis: 3, 2, 1, 1… 1; mucro with a narrow apex, with both edges serrated, with about 46 (inner) and 34 (outer) serrations on each edge, with an apical notch. Ratio mucro: dens: manubrium in holotype 1: 2.83: 1.03.
Distribution: Nangan Island, Matsu, Taiwan. Habitat: Specimens of Ptenothrix matsuensis sp. nov. were found on dead leaves of tree ferns and Miscanthus bushes, similarly to Ptenothrix taiwanensis sp. nov. Sampling localities are presented as green triangles in figure 1. It is noteworthy that Ptenothrix matsuensis sp. nov. was only found during the wet season in Nangan Island, while no specimens were collected during the dry season, a condition that could be related to the life history of the species.
Remarks: Ptenothrix matsuensis sp. nov. is remarkably similar to P. taiwanensis sp. nov. in overall morphology ( Fig. 5 View Fig ), but they appeared as distinct taxa in our analyses of COI phylogeny ( Fig. 6 View Fig ) and K2P distances ( Table 1). Even so, P. matsuensis sp. nov. can be objectively distinguished from P. taiwanensis sp. nov. by: head vertex with an unclear or absent central longitudinal pigment (with a central longitudinal stripe of dark pigment in the latter), frontal head D internal spines as long as the lateral ones (shorter than the lateral ones in P. taiwanensis sp. nov.), manubrium with 7 dorsal chaetae (vs. 8–10 in P. taiwanensis sp. nov.), and only 2 chaetae present between aai1 and ai 6 in the small abdomen of the male of P. matsuensis sp. nov. (3 chaetae present in the male of P. taiwanensis sp. nov.) ( Fig. 12 View Fig ). For further comparisons between similar species of Ptenothrix from Taiwan, South China and Japan, see table 2.
Lectotype designation of Ptenothrix denticulata ( Folsom, 1899)
The type material of Papirius denticulatus Folsom, 1899 in NMNH is a slide-mounted specimen, and is labeled as “ Ptenothrix (Papirius) denticulatus (sic) (Folsom) Type No 5076” and “Komaba, Tokyo, Japan. Coll. C. Ishikawa. Nov. 6. 1894. Lectotype det. by J. T. Salmon, 1938”. Although the specimen is labeled as “ lectotype ” on the slide, the lectotype designation was never formally published, rendering it an invalid type designation under ICZN Art. 74. In 1938, while planning to write a monograph on Collembola of the world, Salmon visited the museums as part of a tour in various institutions in Europe, Great Britain, and the United States to examine and re-describe poorly described Collembola type specimens. Nevertheless, the monograph was never finished. In 1974, the author published the drawings he had completed in the Zoology Publications from Victoria University of Wellington ( Salmon 1974), but Ptenothrix denticulata was not included in this article (Dana M. De Roche, personal communication, January. 12. 2023). As a result, we herein designate the specimen of Papirius denticulatus Folsom, 1899 in the Smithsonian Institution National M u s eu m o f N atu r al H is to r y, Was h in g ton, U S A (catalog no. USNMENT01747048) as the lectotype for Ptenothrix denticulata ( Folsom 1899) .
Betsch JM. 1997. An ontogenetically focused chaetotaxial scheme in Symphypleona (Collembolan). Pedobiologia 41: 13 - 18.
Borner C. 1909. Japans Collembolenfauna. Sitzungsberichte der Gesellschaft Naturforschender Freunde zu Berlin 2: 99 - 135.
Bretfeld G. 1999. Synopses on Palaearctic Collembola: Symphypleona (Vol. 2). Abhandlungen und Berichte des Naturkundemuseums Gorlitz 71: 1 - 318.
Chen JX, Christiansen K. 1996. A new species of Ptenothrix from China (Collembola: Dicyrtomidae). Florida Entomologist 79: 586 - 591. doi: 10.2307 / 3496072.
Cheng HJ, Janssens F, Chang CH. 2022. An updated checklist of Collembola in Taiwan, with DNA barcoding of Papirioides jacobsoni Folsom, 1924 (Symphypleona, Dicyrtomidae). ZooKeys 1123: 123 - 146. doi: 10.3897 / zookeys. 1123.90202.
Fjellberg A. 2007. The Collembola of Fennoscandia and Denmark, part II: Entomobryomorpha and Symphypleona. Fauna Entomologica Scandinavica 42: 1 - 264.
Folsom JW. 1899. Japanese Collembola. Part II. Proceedings of the American Academy of Arts and Sciences 34: 261 - 274.
Itoh R, Zhao LJ. 2000. Five new species of the family Sminthuridae (Collembola) from Yunnan, Southwest China. Taxonomical Studies on the Soil Fauna of Yunnan Province in Southwest China, pp. 147 - 162.
Jo SH, Park KH. 2023. A new species of Ptenothrix Borner, 1906 (Collembola, Symphypleona, Dicyrtomidae) from South Korea. Zootaxa 5301: 124 - 136. doi: 10.11646 / zootaxa. 5301.1.6.
Lin S, Xia F. 1985 a. Four new species of Ptenothrix from Dinghu Mountain, Guangdong (Collembola: Dicyrtomidae). Entomotaxonomia 7: 61 - 67.
Lin S, Xia F. 1985 b. Two new species of Dicyrtomidae (Collembola: Symphypleona). Acta Entomologica Sinica 28: 206 - 209.
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Salmon JT. 1974. Notes and drawings from type material of Collembola. Zoology Publications from Victoria University of Wellington 66: 1 - 41.
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Fig. 5. Habitus of the two new species and subspecies catenata of the P. denticulata group: (A, B, C) Dorsal, lateral, and facial views of Ptenothirx taiwanensis sp. nov., respectively; (D, E, F) Dorsal, lateral, and facial views of Ptenothrix matsuensis sp. nov., respectively; (G, H, I) Dorsal, lateral, and facial of Ptenothrix denticulata catenata Börner, 1909, respectively.
Fig. 7. Ptenothrix taiwanensis sp. nov. left antennal segments, dorsal view: (A) Ant I; (B) Ant II; (C) Ant III with the apical organ (ap. org.), surrounding cup sensilla and a microsensillum (ms); (D) Ant IV with four subdivisions.
Fig. 8. Ptenothrix taiwanensis sp. nov. head: (A) Chaetotaxy of head at frontal view, asterisks indicate unpaired chaetae, black arrows highlight the differences between the lateral and internal chaetae of D line; white arrow indicates a chaeta present or absent, in detail the dotted circles indicate variations of midfacial chaetotaxy; (B) Labral chaetotaxy; (C) Mandible apexes, teeth structure and number vary following the detail at the left; (D) Left maxilla capitulum; (E) Labial palp papilla E (right side); (F) Left maxillary outer lobe and sublobal plate; (G) Left ventral head chaetotaxy including the basal labium (basomedian and basolateral fields).
Fig. 9. Ptenothrix taiwanensis sp. nov. large and small abdomen: (A) Large abdomen chaetotaxy of a female (lateral view), white arrows indicate chaetae presence or absence, the detail under the figure points to coxa III with a short acanthoid chaeta; (B) Small abdomen of female (lateral view) (labels following Betsch 1997); (C) Small abdomen of female (lateral view) (labels following Yosii and Lee 1963); (D) Genital plate of female; (E) Small abdomen of male (lateral view) (labels following Betsch 1997); (F) Small abdomen of male (lateral view) (labels following Yosii and Lee 1963).
Fig. 10. Ptenothrix taiwanensis sp. nov. legs: (A, C, E) Trochanters and femora I, II, III, respectively (anterior view), each with 1 basal microsensillum, white arrow indicates a present or absent chaeta on femur III; (B, D, F) Tibiotarsi I, II, III, each with 1 microsensillum and 2 pairs of oval organs, tibiotarsus III with two modified serrated chaetae at the anterior side.
Fig. 11. Ptenothrix taiwanensis sp. nov. empodial complexes, collophore, and furca: (A–C) Empodial complexes I–III, respectively, lateral lamella of some specimens with a basal extra smaller tooth in the fore and mid legs; (D) Collophore anterior view and lateral flaps; (E) Manubrium dorsal (posterior) chaetotaxy, white arrows indicate present or absent chaetae; (F) Dens dorsal (posterior) chaetotaxy; (G) Dens ventral (anterior) chaetotaxy; (H) Mucro (posterior/dorsal view).
Fig. 12. Morphological comparison of the two new species. Frontal spines on line D of: (A) Ptenothrix taiwanensis sp. nov.; and (B) Ptenothrix matsuensis sp. nov. (white arrows mark the central spines, black arrows mark the lateral spines near the eyes). Small abdomen of a male of: (C) Ptenothrix taiwanensis sp. nov.; and (D) Ptenothrix matsuensis sp. nov. The latter species lacks one chaeta between aai1 and ai6 (marked with a dotted circle in panel D) compared to the former one.
Fig. 13. Ptenothrix taiwanensis sp. nov. SEM (scanning electronic microscope) images: (A) Bothriotrichum A of the large abdomen; (B) Cup sensillum on tibiotarsus; (C) Serrated dental chaetae; (D) Oval organ on tibiotarsus; (E) Microsensillum on tibiotarsus; (F) Modified serrated chaeta on tibiotarsus III; (G) Right eyepatch, dorsal view; (H) Collophore vesicle with warty sacs; (I) Collophore sacs with warty vesicles at ventral view; (J) Tenaculum, lateral view; (K) Lateral view of the empodial complex I, unguis with 2 unpaired inner (black arrows) and 2 lateral teeth; (L) Dorsal view of unguis I, showing the pseudonychia merged with the dorsal unguis, at the apex there is the unguiculus elongated axial filament, slightly knobbed at the tip.
Fig. 6. Maximum Likelihood tree based on COI sequences of Dicyrtomidae species in Taiwan. Genera Papirioides Folsom, 1924 and Ptenothirx are labeled with blue and yellow backgrounds, respectively. The red bar indicates the clade of Ptenothrix taiwanensis sp. nov.; the green bar indicates the clade of Ptenothrix matsuensis sp. nov.. Node values represent the ultrafast bootstrap support (≥ 90%) and SH-aLRT test (≥ 80%) values, respectively. Sminthurus viridis (Sminthuridae, Symphypleona) represents the outgroup.
Fig. 14. Ptenothrix matsuensis sp. nov. main chaetotaxic diagnostic features compared to P. taiwanensis sp. nov.: (A) Head interocular, frontal and interantennal chaetotaxy, black arrows highlight the similar lengths of the lateral and internal chaetae of D line; (B) Large abdomen chaetotaxy (partially represented), white arrows mark chaetae/spines present or absent, the black arrow points to a regular chaeta which is blunt acanthoid in P. taiwanensis sp. nov.; (C) Small abdomen of male (labels following Betsch 1997), black arrows point to two chaetae between aai1 and ai6; (D) Manubrium dorsal (posterior) chaetotaxy, with 7+7 chaetae.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
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Ptenothrix Börner, 1906
| Cheng, Hsin-Ju, Chang, Bruno Cavalcante Bellini Chih-Han, Janssens, Frans & Nakamori, Taizo 2024 |
Ptenothrix denticulata ( Folsom, 1899 )
| Cheng HJ & Janssens F & Chang CH 2022: 137 |