9,110 research outputs found
Nivelen luu-rustorajapinnan mikrometritason kudosmuutoksien tutkiminen nivelrikon eri vaiheissa
No full textAbstractOsteoarthritis (OA) is the most common joint disease that causes disability in the adult population. While the etiology and pathogenesis of OA remain unclear, it is now commonly accepted that the entire joint is affected by OA. The deep zone of hyaline articular cartilage, calcified cartilage, and cortical subchondral bone plate form the osteochondral junction that is specially adapted to transferring loads during weight-bearing and joint motion. Although the OA-related changes in articular cartilage and subchondral trabecular bone have been extensively studied, the changes in the osteochondral junction, especially in the calcified cartilage, remain under explored.Calcified cartilage is a relatively thin tissue layer and has a similar mineral phase to the underlying bone. Hence, it is a major challenge to quantitively study calcified cartilage separately from the whole osteochondral junction, due to the limitations in spatial resolution and the contrast of current microscopic imaging modalities. Therefore, this doctoral dissertation aims to study the biochemical composition, mineral crystal structure, micromechanical and structural properties of calcified cartilage, and the subchondral bone plate in healthy and osteoarthritic knee joints in vitro.Raman microspectroscopy was used to investigate biochemical composition from unfixed and fully hydrated human osteochondral specimens. State-of-the-art micro-focus small-angle X-ray scattering (μSAXS) measurements were performed to map the mineral crystal thickness across the junction. Finally, a bovine patella model was utilized to explore the micromechanical changes in the junction as a function of degeneration and associate these changes with site-specific microstructure.Results show that calcified cartilage had a higher degree of mineralization, with thicker mineral crystals having greater stoichiometric perfection in a proteoglycan-rich matrix than underlying bone. The alterations in the degree of mineralization, type-B carbonate substitutions, mineral crystal thickness, tissue stiffness, and microstructure in both calcified cartilage and subchondral bone plate were observed during OA development. Some of these changes were found to occur at the very early stages of OA. In conclusion, this study shows that both mineralized tissues at the osteochondral junction undergo marked alterations during the evolution of OA, contributing to our current understanding of OA.Original papersOriginal papers are not included in the electronic version of the dissertation.Das Gupta, S., Finnilä, M. A. J., Karhula, S. S., Kauppinen, S., Joukainen, A., Kröger, H., Korhonen, R. K., Thambyah, A., Rieppo, L., & Saarakkala, S. (2020). Raman microspectroscopic analysis of the tissue-specific composition of the human osteochondral junction in osteoarthritis: A pilot study. Acta Biomaterialia, 106, 145–155. https://doi.org/10.1016/j.actbio.2020.02.020Self-archived versionFinnilä, M. A. J., Das Gupta, S., Turunen, M. J., Kestilä, I., Turkiewicz, A., Lutz-Bueno, V., Folkesson, E., Holler, M., Ali, N., Hughes, V., Isaksson, H., Tjörnstrand, J., Önnerfjord, P., Guizar-Sicairos, M., Saarakkala, S., & Englund, M. (2021). Mineral crystal thickness in calcified cartilage and subchondral bone in healthy and osteoarthritic knees. BioRxiv. https://doi.org/10.1101/2021.06.15.448181Das Gupta, S., Finnilä, M. A. J., Rieppo, L., Turunen, M. J., Kestilä, I., Lutz-Bueno, V., Folkesson, E., Ali, N., Hughes, V., Isaksson, H., Tjörnstrand, J., Önnerfjord, P., Turkiewicz, A., Englund, M., & Saarakkala, S. (2021). Mineral composition of calcified cartilage and subchondral bone plate in humans with and without knee osteoarthritis. Manuscript in preparation.Das Gupta, S., Workman, J., Finnilä, M. A. J., Saarakkala, S., & Thambyah, A. (2022). Subchondral bone plate thickness is associated with micromechanical and microstructural changes in the bovine patella osteochondral junction with different levels of cartilage degeneration. Journal of the Mechanical Behavior of Biomedical Materials, 129, 105158. https://doi.org/10.1016/j.jmbbm.2022.105158Self-archived versionTiivistelmäNivelrikko on aikuisväestön yleisin invalidoiva nivelsairaus. Nivelrikon tarkkaa syntytapaa ei edelleenkään tiedetä, mutta nykyisin on yleisesti hyväksytty, että nivelrikko vaikuttaa kaikkiin nivelen kudoksiin. Nivelessä sijaitseva luu-rustorajapinta muodostuu hyaliiniruston pohjakerroksen, kalkkeutuneen ruston ja rustonalaisen luun yhdistelmästä. Luu-rustorajapinnan rooli on välittää mekaanista kuormitusta rustosta luuhun nivelen liikkuessa. Nivelruston ja sen alaisen luun kudosmuutoksia nivelrikon eri vaiheissa on tutkittu laajasti, mutta luu-rustorajapinnan — erityisesti kalkkeutuneen ruston — kudosmuutoksia nivelrikon aikana on tutkittu vain vähän.Kalkkeutunut rusto on ohut kudoskerros, jossa on myös mineraalifaasi samoin kuin alla olevassa luukudoksessa. Tämä tekee kalkkeutuneen ruston kvantitatiivisesta tutkimisesta hankalaa, koska luun ja kalkkeutuneen ruston erottaminen on vaikeaa mikroskooppisten kuvantamismenetelmien rajoittuneen kontrastin ja erotuskyvyn vuoksi. Tässä väitöskirjassa tutkittiin nivelrikkoisen ja terveen kalkkeutuneen ruston biokemiallista koostumusta, mikrorakennetta sekä mikromekaanisia ominaisuuksia.Ihmisestä saatuja tuoreita ja käsittelemättömiä luu-rustonäytteitä tutkittiin aluksi Raman-mikroskopialla, jonka perusteella kartoitettiin niiden biokemiallista koostumusta eri kohdissa kudosta. Mineraalikristalleja analysoitiin pienkulmaröntgensironnan avulla, jolla pystyttiin kartoittamaan kristallien paksuutta koko luu-rustorajapinnan alueelta. Tutkimuksessa käytettiin myös naudan polvilumpiosta otettuja näytteitä, joiden avulla tutkittiin luu-rustorajapinnan mikromekaanisia muutoksia nivelrikon eri kehitysvaiheissa. Lisäksi tutkittiin mikromekaanisten muutoksien ja mikrorakenteen muutoksien välistä yhteyttä toisiinsa.Tulokset osoittavat, että kalkkeutuneessa rustossa on luuhun verrattuna korkeampi mineralisoitumisen aste, paksummat ja stoikiometrisesti täydellisemmät mineraalikristallit, sekä suurempi proteoglykaanipitoisuus. Lisäksi tutkimuksessa havaittiin selkeitä muutoksia mineralisaation määrässä, tyypin B karbonaattisubstituutiossa, mineraalikristallien paksuudessa, kudoksen jäykkyydessä sekä mikrorakenteessa nivelrikon kehittyessä. Osa muutoksista havaittiin hyvin varhaisessa nivelrikon kehitysvaiheessa. Tässä väitöskirjassa saatiin tärkeää uutta tietoa siitä, että luu-rustorajapinnnassa tapahtuu merkittäviä muutoksia nivelrikon kehittyessä. Tämä lisää nykyistä tietämystämme nivelrikon etiologiasta.OsajulkaisutOsajulkaisut eivät sisälly väitöskirjan elektroniseen versioon.Das Gupta, S., Finnilä, M. A. J., Karhula, S. S., Kauppinen, S., Joukainen, A., Kröger, H., Korhonen, R. K., Thambyah, A., Rieppo, L., & Saarakkala, S. (2020). Raman microspectroscopic analysis of the tissue-specific composition of the human osteochondral junction in osteoarthritis: A pilot study. Acta Biomaterialia, 106, 145–155. https://doi.org/10.1016/j.actbio.2020.02.020Rinnakkaistallennettu versioFinnilä, M. A. J., Das Gupta, S., Turunen, M. J., Kestilä, I., Turkiewicz, A., Lutz-Bueno, V., Folkesson, E., Holler, M., Ali, N., Hughes, V., Isaksson, H., Tjörnstrand, J., Önnerfjord, P., Guizar-Sicairos, M., Saarakkala, S., & Englund, M. (2021). Mineral crystal thickness in calcified cartilage and subchondral bone in healthy and osteoarthritic knees. BioRxiv. https://doi.org/10.1101/2021.06.15.448181Das Gupta, S., Finnilä, M. A. J., Rieppo, L., Turunen, M. J., Kestilä, I., Lutz-Bueno, V., Folkesson, E., Ali, N., Hughes, V., Isaksson, H., Tjörnstrand, J., Önnerfjord, P., Turkiewicz, A., Englund, M., & Saarakkala, S. (2021). Mineral composition of calcified cartilage and subchondral bone plate in humans with and without knee osteoarthritis. Manuscript in preparation.Das Gupta, S., Workman, J., Finnilä, M. A. J., Saarakkala, S., & Thambyah, A. (2022). Subchondral bone plate thickness is associated with micromechanical and microstructural changes in the bovine patella osteochondral junction with different levels of cartilage degeneration. Journal of the Mechanical Behavior of Biomedical Materials, 129, 105158. https://doi.org/10.1016/j.jmbbm.2022.105158Rinnakkaistallennettu versioAcademic dissertation to be presented with the assent of the Doctoral Programme Committee of Health and Biosciences of the University of Oulu for public defence in the Markku Larmas auditorium (H1091) in Dentopolis, on 12 August 2022, at 12 noonAbstract
Osteoarthritis (OA) is the most common joint disease that causes disability in the adult population. While the etiology and pathogenesis of OA remain unclear, it is now commonly accepted that the entire joint is affected by OA. The deep zone of hyaline articular cartilage, calcified cartilage, and cortical subchondral bone plate form the osteochondral junction that is specially adapted to transferring loads during weight-bearing and joint motion. Although the OA-related changes in articular cartilage and subchondral trabecular bone have been extensively studied, the changes in the osteochondral junction, especially in the calcified cartilage, remain under explored.
Calcified cartilage is a relatively thin tissue layer and has a similar mineral phase to the underlying bone. Hence, it is a major challenge to quantitively study calcified cartilage separately from the whole osteochondral junction, due to the limitations in spatial resolution and the contrast of current microscopic imaging modalities. Therefore, this doctoral dissertation aims to study the biochemical composition, mineral crystal structure, micromechanical and structural properties of calcified cartilage, and the subchondral bone plate in healthy and osteoarthritic knee joints in vitro.
Raman microspectroscopy was used to investigate biochemical composition from unfixed and fully hydrated human osteochondral specimens. State-of-the-art micro-focus small-angle X-ray scattering (μSAXS) measurements were performed to map the mineral crystal thickness across the junction. Finally, a bovine patella model was utilized to explore the micromechanical changes in the junction as a function of degeneration and associate these changes with site-specific microstructure.
Results show that calcified cartilage had a higher degree of mineralization, with thicker mineral crystals having greater stoichiometric perfection in a proteoglycan-rich matrix than underlying bone. The alterations in the degree of mineralization, type-B carbonate substitutions, mineral crystal thickness, tissue stiffness, and microstructure in both calcified cartilage and subchondral bone plate were observed during OA development. Some of these changes were found to occur at the very early stages of OA. In conclusion, this study shows that both mineralized tissues at the osteochondral junction undergo marked alterations during the evolution of OA, contributing to our current understanding of OA.Tiivistelmä
Nivelrikko on aikuisväestön yleisin invalidoiva nivelsairaus. Nivelrikon tarkkaa syntytapaa ei edelleenkään tiedetä, mutta nykyisin on yleisesti hyväksytty, että nivelrikko vaikuttaa kaikkiin nivelen kudoksiin. Nivelessä sijaitseva luu-rustorajapinta muodostuu hyaliiniruston pohjakerroksen, kalkkeutuneen ruston ja rustonalaisen luun yhdistelmästä. Luu-rustorajapinnan rooli on välittää mekaanista kuormitusta rustosta luuhun nivelen liikkuessa. Nivelruston ja sen alaisen luun kudosmuutoksia nivelrikon eri vaiheissa on tutkittu laajasti, mutta luu-rustorajapinnan — erityisesti kalkkeutuneen ruston — kudosmuutoksia nivelrikon aikana on tutkittu vain vähän.
Kalkkeutunut rusto on ohut kudoskerros, jossa on myös mineraalifaasi samoin kuin alla olevassa luukudoksessa. Tämä tekee kalkkeutuneen ruston kvantitatiivisesta tutkimisesta hankalaa, koska luun ja kalkkeutuneen ruston erottaminen on vaikeaa mikroskooppisten kuvantamismenetelmien rajoittuneen kontrastin ja erotuskyvyn vuoksi. Tässä väitöskirjassa tutkittiin nivelrikkoisen ja terveen kalkkeutuneen ruston biokemiallista koostumusta, mikrorakennetta sekä mikromekaanisia ominaisuuksia.
Ihmisestä saatuja tuoreita ja käsittelemättömiä luu-rustonäytteitä tutkittiin aluksi Raman-mikroskopialla, jonka perusteella kartoitettiin niiden biokemiallista koostumusta eri kohdissa kudosta. Mineraalikristalleja analysoitiin pienkulmaröntgensironnan avulla, jolla pystyttiin kartoittamaan kristallien paksuutta koko luu-rustorajapinnan alueelta. Tutkimuksessa käytettiin myös naudan polvilumpiosta otettuja näytteitä, joiden avulla tutkittiin luu-rustorajapinnan mikromekaanisia muutoksia nivelrikon eri kehitysvaiheissa. Lisäksi tutkittiin mikromekaanisten muutoksien ja mikrorakenteen muutoksien välistä yhteyttä toisiinsa.
Tulokset osoittavat, että kalkkeutuneessa rustossa on luuhun verrattuna korkeampi mineralisoitumisen aste, paksummat ja stoikiometrisesti täydellisemmät mineraalikristallit, sekä suurempi proteoglykaanipitoisuus. Lisäksi tutkimuksessa havaittiin selkeitä muutoksia mineralisaation määrässä, tyypin B karbonaattisubstituutiossa, mineraalikristallien paksuudessa, kudoksen jäykkyydessä sekä mikrorakenteessa nivelrikon kehittyessä. Osa muutoksista havaittiin hyvin varhaisessa nivelrikon kehitysvaiheessa. Tässä väitöskirjassa saatiin tärkeää uutta tietoa siitä, että luu-rustorajapinnnassa tapahtuu merkittäviä muutoksia nivelrikon kehittyessä. Tämä lisää nykyistä tietämystämme nivelrikon etiologiasta
Narratives from the Margins: Aspects of Adivasi History in India
No full textHistorians have studied adivasis principally in the context of rebellion, environmental history and the politics of identity. However, preoccupations with definitions and notions of identity, while important in themselves, tend to shift attention away from the inner lives of these communities. This book deals with different aspects of the histories of adivasi communities of the central belt of India – from Rajasthan in the west to Bengal and Orissa in the east. The editors have brought together essays which discuss a range of issues affecting the socio-economic and cultural life of adivasis and explore the long term continuities and discontinuities between different political regimes. The book thus reflects some of their concerns relating to methodology and sources, historiography, the impact of colonialism, gender issues, the agrarian situation, famines and migration. The book will be of use to students and scholars of history, anthropology and sociology and also to policy-planners concerned with ‘tribal’ issues
Evaluation of grain boundaries as percolation pathways in quartz-rich continental crust using Atomic Force Microscopy
No full textHydrous fluids play a vital role in the chemical and rheological evolution of ductile, quartz-bearing continental crust, where fluid percolation pathways are controlled by grain boundary domains. In this study, widths of grain boundary domains in seven quartzite samples metamorphosed under varying crustal conditions were investigated using Atomic Force Microscopy (AFM) which allows comparatively easy, high magnification imaging and precise width measurements. It is observed that dynamic recrystallization at higher metamorphic grades is much more efficient at reducing grain boundary widths than at lower temperature conditions. The concept of force-distance spectroscopy, applied to geological samples for the first time, allows qualitative estimation of variations in the strength of grain boundary domains. The strength of grain boundary domains is inferred to be higher in the high grade quartzites, which is supported by Kernel Average Misorientation (KAM) studies using Electron Backscatter Diffraction (EBSD). The results of the study show that quartzites deformed and metamorphosed at higher grades have narrower channels without pores and an abundance of periodically arranged bridges oriented at right angles to the length of the boundary. We conclude that grain boundary domains in quartz-rich rocks are more resistant to fluid percolation in the granulite rather than the greenschist facies
Culicoides quasiregalis Majumdar & Das Gupta
No full textCulicoides quasiregalis Majumdar & Das Gupta (Fig 7a–g) Culicoides quasiregalis Majumdar & Das Gupta, in Majumdar, Das Gupta & Gangopadhyay 1997: 30; Majumdar 1972: 180– 183; Nandi 2014:101–102 Materials examined. Holotype (1 ♀), Darjeeling Govt. College, August, 1968, Coll. Dr. S.K. Das Gupta. Diagnosis. Poststigmatic pale spot ended before vein M 1; anal cell with two separated proximal pale spots and narrowly constricted distal pale spot. Female. Head (Figs 7a and 7b). Eyes contiguous for 2 facets. Antenna with SCo on flagellomeres 1, 9–13. Third palpal segment long, slender with numerous capitate sensilla, without sensory pit; first, fourth, fifth segments short, stout; second segment long. Thorax (Fig. 7c). Brown; scutum with dark linear streaks; scutellum with 8 bristles; postscutellum brownish. Legs (Figs.7d and 7e). Brownish; fore femora with pale apical bands, mid femora with pale basal and apical bands, hind femora with basal band, fore and mid tibiae with broad pale basal bands, hind tibiae with pale broad basal and apical bands; hind tibial comb with 5 unequal spines, second from spur longest; spur tip frayed; claws equal. Wings (Fig. 7f). A clear dark marking on anal corner; pale spot on r-m crossvein extending distally to vein M; poststigmatic pale spot covering most of 2 nd radial cell, not reaching vein M 1; a large pale spot in cell r 3; cells m 1 and m 2 each with two spots; a pale streak bordering vein M 1; cell cua 1 with a triangular pale spot, extending from vein CuA 1 to wing margin; anal cell with a narrowly constricted distal pale spot. Abdomen (Fig. 7g). Brown with dark streaks; two well developed, brown, unequal, ovoid, spermathecae well sclerotized with short necks; rudimentary spermatheca small. Male. Unknown Immatures. Unknown Larval habitat. Unknown Distribution. India (Darjeeling, Kurseong, West Bengal) Remarks. C. quasiregalis most closely resembles C. pseudoregalis as both have grayish wing, hind tibial comb with 5 spines but the two species differ in antennal and palpal ratios (Table 1) and the presence of a discrete constricted distal pale spot in the anal cell.This character may be variable, assumed to be a variant of C. pseudoregalis but this requires further investigations.Published as part of Sarkar, Ankita, Banerjee, Paramita, Sinha, Shuvra Kanti & Mazumdar, Abhijit, 2023, A taxonomic revision of the Indian species of the ' Aterinervis' group of Culicoides Latreille Subgenus Hoffmania Fox (Diptera: Ceratopogonidae), pp. 405-428 in Zootaxa 5258 (4) on pages 417-418, DOI: 10.11646/zootaxa.5258.4.3, http://zenodo.org/record/778442
Culicoides pararegalis Majumdar & Das Gupta
No full textCulicoides pararegalis Majumdar & Das Gupta (Fig 5a–i) Culicoides pararegalis Majumdar & Das Gupta, in Majumdar, Das Gupta & Gangopadhyay 1997: 28; Majumdar 1972: 165– 168; Nandi 2014: 92–93 Material examined. Holotype (1 ♀), Darjeeling Govt. College, 25.vi.1968, Coll. Dr. S.K. Das Gupta; 1 ♀, PHE camp, Neora Valley National Park, 14.iii.2021, Coll. S.K. Sinha. Diagnosis. Pale spot over r-m cross vein broad, extending to cell m 2; distal pale spot on cells r 3 and m 1 reduced, distant from wing margin; anal cell with two separated distal pale spots. Female. Head (Figs. 5a and 5b). Eyes contiguous, for 3 facets. Antenna with SCo on flagellomeres 1, 9–13; third palpal segment long, slender, numerous capitate sensilla, second segment long, with minute capitate sensilla, first, fourth and fifth segments short, fifth segment with 4 apical sensilla chaetica. Thorax (Fig. 5c). Brown with random dark markings; postscutellum brown. Legs (Figs 5d and 5e). Brownish; fore femora with pale apical bands, mid femora with narrow pale area at base, apex pale, hind femora basally pale, fore and mid tibia with broad pale band in basal half, hind tibia with pale basal and apical bands; hind tibial comb with 6 unequal spines, second one longest; spur tip frayed; claws equal. Wing (Fig. 5f). Pale area at wing base extending to posterior wing margin of anal cell; pale spot over r-m crossvein crossing vein M, continuous to cell m 2; a large poststigmatic pale spot including almost entire 2 nd radial cell expanded at wing margin, ending posteriorly before vein M 1; pale spot in cell r 3 reduced, not reaching wing margin, closer to vein M 1 than to wing margin; pale streak parallel to vein M 1; cell m 1 with a distal small, oval pale spot separated from wing margin; cell m 2 with additional two spots, one overlying over Cu fork, distal one larger, narrowly separated from wing margin; cell cua 1 with a pale spot extending to posterior wing margin, proximal portion of dark spot over vein CuA 2 expanded, posteriorly tapered; anal cell with two rounded distal spots. Abdomen ( Figs. 5h and 5i). Brownish with dark streaks; spermatheca two, well developed, ovoid, subequal, well sclerotized with short, oblique prominent necks; rudimentary one small, tubular; ring indistinct. Male. Unknown Immatures. Unknown Larval habitat. Unknown Distribution. India (Darjeeling, Neora Valley National Park, West Bengal) Remarks. C. pararegalis similar to C. regalis as pale area of wing base extending to posterior wing margin of anal cell and with a broad pale spot over r-m crossvein. Additionally, the morphometric data (Table 1) of these species overlaps suggesting that C. pararegalis may just be a variant of the more widespread C. regalis. The major difference between these species is the reduced distal pale spot in cell r 3 and two separate distal pale spots in anal cell of C. pararegalis, warrant further investigation to confirm the status of C. pararegalis.Published as part of Sarkar, Ankita, Banerjee, Paramita, Sinha, Shuvra Kanti & Mazumdar, Abhijit, 2023, A taxonomic revision of the Indian species of the ' Aterinervis' group of Culicoides Latreille Subgenus Hoffmania Fox (Diptera: Ceratopogonidae), pp. 405-428 in Zootaxa 5258 (4) on page 414, DOI: 10.11646/zootaxa.5258.4.3, http://zenodo.org/record/778442
Culicoides subregalis Majumdar & Das Gupta
No full textCulicoides subregalis Majumdar & Das Gupta (Fig 9a–i) Culicoides subregalis Majumdar & Das Gupta, in Majumdar, Das Gupta & Gangopadhyay 1997: 31; Majumdar 1972: 228–232; Nandi 2014: 104–106 Materials examined. Holotype (1 ♀), Darjeeling Govt. College, 23.vi.1968, Coll. Dr. S.K. Das Gupta; Allotype (1 ♁), Darjeeling Govt. College, 09.vi.1968, Coll. Dr. S.K. Das Gupta; 12 ♀, 2 ♁, Bhotaykhadka, Neora Valley National Park, 19.x.2019, Coll. S.K. Sinha. Diagnosis. Broad dark band apical to r-m crossvein; indistinct pale spot anterior to Cu fork; anal cell with elongate distal pale spot; posterior margin of tergum IX terminating much before apex of gonocoxite. Female. Head (Figs. 9a and 9b). Antenna with SCo on flagellomeres 1, 9–13. Third palpal segment long, slender, tapering past middle bearing capitate sensilla, without sensory pit; fifth segment with 4 apical sensilla. Mandible with basal 4–5 teeth broad. Thorax. Scutum brown, anterior, posterior portion dark brown; humeral region pale; postscutellum dark brown. Legs (Figs 9c and 9d). Brownish; femora indistinctly pale at bases, fore and mid femora with pale apical bands, tibiae pale at bases; hind tibial comb with 5– 6 spines, second one longest; spur tip frayed; claws equal. Wing (Fig. 9f). Dark area at anal angle; pale spot over r-m crossvein narrow, crossing vein M; poststigmatic pale spot covering half of 2 nd radial cell, meeting costa but not reaching vein M 1, distal pale spot distinctly distant from apical wing margin; cell m 1 with an elongate distal pale spot distant from wing margin; cell m 2 with an indistinct pale spot anterior to Cu fork and distal pale spot broadly meeting wing margin; cell cua 1 with broad large pale spot extending posteriorly to wing margin; anal cell with a long distal pale spot, perpendicular to and continuous to posterior wing margin. Abdomen (Fig. 9g). Brownish with dark tergal streaks; spermatheca two, well developed, pear shaped, subequal, moderately sclerotized with distinct oblique necks; third rudimentary one finger like; small ring present. Male. Similar to female with usual sexual differences. Genitalia (Figs 9h and 9i). Sternum IX broad with shallow caudomedian excavation. Tergum IX quadrate with round apical margin, a narrow medial cleft, without apicolateral process; posterior margin of tergum IX terminating much before apex of gonocoxite. Gonocoxite broad basally, apex narrow with distinct dorsal root. Gonostylus dilated at base, slightly curved medially, ending in blunt tip. Aedeagus weakly sclerotized with short, bent basal arms. Parameres with sclerotized basal arms with broad base, stem dilated basally, gradually tapering. Immatures. Unknown Larval habitat. Unknown Distribution. India (Darjeeling, Neora Valley National Park, West Bengal) Remarks. This species differs from C. regalis in antennal ratio, width of the pale spot over r-m crossvein, extent of pale area at wing base to anal angle and the long distal pale spot in the anal cell. C. subregalis is closest to C. isoregalis and C. isoregalis seems to be a variant of this species as morphometric data of these two species overlap and but differs in scutal colour, elongated pale spot in cell m 1 and shape of pale spot in cell cua 1 that may be resulted due to intraspecific variation but status of these species need to be further strengthened by studying more specimens or by molecular approaches.Published as part of Sarkar, Ankita, Banerjee, Paramita, Sinha, Shuvra Kanti & Mazumdar, Abhijit, 2023, A taxonomic revision of the Indian species of the ' Aterinervis' group of Culicoides Latreille Subgenus Hoffmania Fox (Diptera: Ceratopogonidae), pp. 405-428 in Zootaxa 5258 (4) on pages 421-422, DOI: 10.11646/zootaxa.5258.4.3, http://zenodo.org/record/778442
Culicoides pseudoregalis Majumdar & Das Gupta
No full textCulicoides pseudoregalis Majumdar & Das Gupta (Fig 6a–h) Culicoides pseudoregalis Majumdar & Das Gupta, in Majumdar, Das Gupta & Gangopadhyay 1997: 30; Majumdar 1972: 176–180; Nandi 2014: 99–100 Materials examined. Holotype (1 ♀), Darjeeling Govt. College, 24.viii.1968, Coll. Dr. S.K. Das Gupta. 1 ♀, Bhotaykhadka, Neora Valley National Park, 19.x.2019, Coll. S. K. Sinha. Diagnosis. Poststigmatic pale spot ended before vein M 1; anal cell with two constricted proximal and distal hourglass shaped pale spots. Female. Head (Figs. 6a and 6b). Antenna with SCo on flagellomeres 1, 9–13; first flagellomere whitish at basal half, distal half brown, flagellomeres 2–13 brown. Third palpal segment long, slender with minute capitate sensilla, without sensory pit; first segment short, second segment stout, fourth, fifth segments short, 4 apical sensilla in fifth segment. Thorax (Fig. 6c). Brown; scutum with distinct median pale streak; scutellum dark; postscutellum dark brown. Legs (Figs. 6d and 6e). Brownish; fore and mid femora with pale apical bands, mid and hind femora with pale bases, fore and mid tibiae with broad basal bands, hind tibia with apical, basal pale band; hind tibial comb with 5 spines, second one longest; spur tip frayed; claws equal. Wing (Fig. 6f). Grayish; dark area at anal angle; pale spot over r-m crossvein narrow, reaching vein M; poststigmatic pale spot not reaching vein M 1; dark band apical to r-m crossvein broadly touching costal margin, continuous posteriorly to cell m 2; distal pale spot in cell r 3 not reaching wing margin; cell m 1 with an oval, distal pale spot distant from wing margin, dark streaks overlying vein M 1, distally with pale streaks; total three pale spots present in cell m 2, proximal pale spot present overlying Cu fork, next one confluent with pale spot in cell m 1 and third distal one touching wing margin; cell cua 1 with a large triangular pale spot touching wing margin, narrowly separated from vein CuA 2, anal cell with two narrowly constricted proximal and distal pale spots. Macrotrichia restricted to apical, posterior wing blade. Abdomen (Fig. 6h). Brownish with dark streaks; two well developed, unequal, oval spermathecae well sclerotized with prominent, straight necks; rudimentary spermatheca more or less bladder-like; sclerotized ring present. Male. Unknown. Immatures. Unknown Larval habitat. Unknown Distribution. India (Darjeeling, Neora Valley National Park, West Bengal) Remarks. C. pseudoregalis is similar in appearance to C. quasiregalis in having pale area at wing base extending to anal angle and a dark marking in the anal corner but differs slightly in antennal and palpal ratios and two constricted pale spots. These characters may represent intraspecific variability but this requires studying more specimens. This species differs from C. neoregalis and C. regalis in possessing a narrow pale spot over r-m crossvein, two narrowly constricted pale spots in anal cell, dark marking in anal corner. It is distinguished from C. pararegalis by possessing a higher antennal ratio, smaller palpal ratio (Table 1), hind tibial comb with 5 spines and a large distal pale spot in cell r 3.Published as part of Sarkar, Ankita, Banerjee, Paramita, Sinha, Shuvra Kanti & Mazumdar, Abhijit, 2023, A taxonomic revision of the Indian species of the ' Aterinervis' group of Culicoides Latreille Subgenus Hoffmania Fox (Diptera: Ceratopogonidae), pp. 405-428 in Zootaxa 5258 (4) on pages 416-417, DOI: 10.11646/zootaxa.5258.4.3, http://zenodo.org/record/778442
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