|
| Number of characters | State of characters |
|
| K0. Mandibular file | (0) Evenly serrated (short spines) and medium length; Mesovelia furcata, Belostomatinae |
| (1) Evenly serrated (short spines) and short length; Nepidae |
| (2) Evenly grooved (blunt pegs) and medium length; Gelastocorinae |
| (3) Evenly grooved (blunt pegs) and long; Nerthrinae |
| (4) Evenly grooved (massive plates) and medium length; Corixoidea |
| (5) Unevenly serrated (short and long spines) and medium length; |
| Ochteridae and Aphelocheiridae |
| (6) Unevenly serrated (blunt pegs, short and long spines) and long; Cheirochelinae: Cheirochela feana and Gestroiella limnocoroides |
| (7) Unevenly serrated (blunt pegs and long spines) and medium length; Tanycricos longiceps, Laccocoris hoogstraali, Helocoris humeralis, Pelocoris femoratus, Ambrysus occidentalis, Cryphocricos hungerfordi, Macrocoris rhantoides, Neomacrocoris handlirschi, Limnocoris lutzi, and Notonectidae |
| (8) Unevenly serrated (plaques, nodule and long spines) and long; Pleidae |
| (9) Unevenly serrated (blunt pegs, short spines, nodule, long spines) and long: Helotrephidae |
| (?) Lack of data; Potamocoridae, Coptocatus oblongulus, Coptocatus kinabalu, Naucoris maculatus, Namtokocoris siamensis |
|
| K1. Shapes of the apices of the maxillae | (0) Symmetrical apices (both apices straight, slightly narrow and flat); Mesovelia furcata |
| (1) Symmetrical apices (both apices straight and narrow); Gelastocoris oculatus, Nerthra nepaeformis, N. macrothorax |
| (2) Asymmetrical apices (the right one straight, the left one with a narrow lobe); Nepidae and Belastomatidae |
| (3) Asymmetrical apices (the right one curved, the left one straight and narrow); Ochterus marginatus, O. perbosci |
| (4) Asymmetrical apices (the right one straight and narrow, the left one wide and curved), Aphelocheiridae, Potamocoridae, Coptocatus oblongulus, Coptocatus kinabalu, Cheirochela feana, and Gestroiella limnocoroides |
| (5) Asymmetrical apices (the right one straight and tapered, the left one lancet-shaped); Laccocoris hoogstraali, Helocoris humeralis, Ilyocoris cimicoides, Pelocoris femoratus, Ambrysus occidentalis, Cryphocricos hungerfordi, Macrocoris rhantoides, Naucoris maculatus, Namtokocoris siamensis, Limnocoris lutzi, Notonectidae, Pleidae, and Helotrephidae |
| (6) Asymmetrical apices (the right one straight and tapered, the left one cap-like) Neomacrocoris handlirschi (Naucorinae) |
| (7) Asymmetrical apices (the right one flat and blunt, the left one sharp, long and hooked); Corixoidea |
| (?) Lack of data; Gelastocoris bufo, Ochterus piliferus, Tanycricos longiceps |
|
| K2. Rupturing device | (0) Exposed; the dorsal external (brdex) and internal bristles (brdin) and ventral external (brvex) and internal bristles (brvin) densely arranged in rows along the edges of the maxillae; Mesovelia furcata |
| (1) Exposed; external and internal bristles in rows along the ventral and dorsal edges of the maxillae, stiff bristles (brvex) sparsely arranged and separated from one other; Belostoma flumineum, Deinostoma dilatatum, Appasus major, Hydrocyrius colombiae, Lethocerus deyrollei, Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, Nepa cinerea, Cercotmetus asiaticus, Ranatra chinensis, R. linearis. |
| (2) Exposed; external and internal short spines (spvex, spdex, spvin); Limnogeton fieberi |
| (3) Exposed; dorsal bristles (brdex) very short; Ochteridae and Gelastocorinae |
| (4) Exposed; stiff bristles (brvex) distributed along the ventral edges; Tanycricos longiceps, Cheirochela feana and Gestroiella limnocoroides, Laccocoris hoogstraali, Helocoris humeralis, Ilyocoris cimicoides, Ambrysus occidentalis, Cryphocricos hungerfordi, Macrocoris rhantoides, Naucoris maculatus, Namtokocoris siamensis, and Limnocoris lutzi |
| (5) Exposed; dorsal bristles (brdex) smaller than the ventral ones and slightly visible; Coptocatus oblongulus, C. kinabalu, and Pelocoris femoratus |
| (6) Exposed; the bristles arranged in tufts on the dorsal (brdex) and ventral (brvex) edges; Neomacrocoris handlirschi |
| (7) Hidden; short bristles (brvex, brdex) placed flat against the insides of the maxillae; Aphelocheiridae, Buenoa uhleri, Anisops sardea, Anisops camaroonensis, Enithares bergrothi, Notonecta glauca, and Nychia sappho |
| (8) Hidden; ventral bristles (brvin) inside of the maxillae; Nerthrinae, |
| (9) Almost reduced; externally the maxillae totally smooth; inside, preapically, the right maxilla with seven very short spines; Corixoidea, Potamocoridae, Pleidae, and Helotrephidae |
| (?) Lack of data; Gelastocoris bufo |
|
| K3. Cross-section of the maxillae | (0) Trapezoid-shaped maxillae with four short external processes; Mesovelia furcata |
| (1) Dorsolaterally extended maxillae with two wide lobes (processes); most of the Nepidae (except for Ranatra chinensis and R. linearis) and all Belostomatidae, Gelastocoridae, Naucoridae, Pleidae, Helotrephidae, and Notonectidae |
| (2) Ventrolaterally extended maxillae with a wide lobe; Aphelocheiridae |
| (3) Pentagonal-shaped maxillae with two external lobes; Ochteridae |
| (4) Oval maxillae, flattened laterally without the external lobe; Ranatra chinensis, R. linearis, and corixoids species |
| (?) Lack of data; Potamocoridae |
|
| K4. Cross-section of the mandible | (0) Short, suboval mandibles situated between dorsal and ventral external processes and not overlapped by the maxillae; Mesovelia furcata |
| (1) Mandibles completely surrounded by the maxillae; Belostomatidae |
| (2) Mandibles only partly overlapped by the maxillae; remaining species of Nepomorpha |
| (?) Lack of data; Potamocoridae |
|
| K5. Chaetica sensilla CH3 | (0) Present on the III and IV segments: Mesovelia furcata |
| (1) Present on the I, II, and III segments: Belostoma flumineum, Deinostoma dilatatum, Appasus major, Hydrocyrius colombiae, Limnogeton fieberi, Coptocatus oblongulus, Coptocatus kinabalu, and Tanycricos longiceps |
| (2) Present on the IV segment: Cercotmetus asiaticus, Ranatra chinensis, R. linearis,and Hydrotrephes visayasensis |
| (3) Present on the III segment: Ochterus piliferus, O. marginatus, Gelastocoris oculatus, Limnocoris lutzi, and Corixoidea, |
| (4) Present on the I and II segments: Nerthra nepaeformis, N. macrothorax, Aphelocheirus variegatus, A. aestivalis, Cheirochela feana, and Gestroiella limnocoroides |
| (5) Present on the II and III segments: Lethocerus deyrollei, Laccocoris hoogstraali, Heleocoris humeralis, Cryphocricos hungerfordi, Ambrysus occidentalis, Macrocoris rhantoides, Naucoris maculatus, and Neomacrocoris handlirschi |
| (6) Present on the II, III, and IV segments: Ilyocoris cimicoides, Pelocoris femoratus, Paraplea frontalis, Hydrotrephes balnearius, and Tiphotrephes indicus |
| (7) Present on the I, II, III, and IV segments: Anisops camaroonensis, A. sardea, Buenoa uhleri, Notonecta glauca, Enithares bergrothi, and Nychia sappho |
| (8) Absent: Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, Nepa cinerea, Namtokocoris siamensis, and Helotrephes semiglobosus |
| (?) Lack of data: Potamocoridae |
|
| K6. Chaetica sensilla CH2 | (0) Present on the I and II segments: Mesovelia furcata, Ochterus piliferus, O. marginatus, Nerthra nepaeformis, and N. macrothorax |
| (1) Present on the II and III segments: Belostoma flumineum, Deinostoma dilatatum, Appasus major, Hydrocyrius colombiae, Limnogeton fieberi, and Lethocerus deyrollei |
| (2) Present on the IV segment: Curicta granulosa, Borborophyes mayri, Nepa cinerea, Cercotmetus asiaticus, Ranatra chinensis, and R. linearis |
| (3) Present on the I and III segments: Gelastocoris oculatus, Coptocatus oblongulus, and Coptocatus kinabalu |
| (4) Present on the I, II, and III segments: Aphelocheirus variegatus, A. aestivalis, Notonecta glauca, and Enithares bergrothi |
| (5) Present on the II, III, and IV segments: Helotrephes semiglobosus, Hydrotrephes visayasensis, and Buenoa uhleri |
| (6) Present on the I segment: Ambrysus occidentalis |
| (7) Present on the II segment: Tanycricos longiceps, Laccocoris hoogstraali, Heleocoris humeralis, Limnocoris lutzi, Cryphocricos hungerfordi, Ilyocoris cimicoides, Pelocoris femoratus, Macrocoris rhantoides, Naucoris maculatus, Neomacrocoris handlirschi, and Namtokocoris siamensis |
| (8) Present on the III segment: Paraplea frontalis, Plea minutissima, Hydrotrephes balnearius, Tiphotrephes indicus, and Corixoidea |
| (9) Absent: Laccotrephes japonensis, Cheirochela feana, Gestroiella limnocoroides, Anisops camaroonensis, Anisops sardea, and Nychia sappoho |
| (?) Lack of data: Potamocoridae |
|
| K7. Chaetica sensilla CH1 | (0) Present on the I and II segments: Mesovelia furcata, Ochterus piliferus, and O. marginatus |
| (1) Present on the II and III segments: Belostoma flumineum, Deinostoma dilatatum, Appasus major, Limnogeton fieberi, Laccotrephes japonensis, Namtokocoris siamensis, Anisops camaroonensis, Anisops sardea, and Enithares bergrothi |
| (2) Present on the I, II, and III segments: Notonecta glauca |
| (3) Present on the IV segment: Curicta granulosa, Borborophyes mayri, Nepa cinerea, Cercotmetus asiaticus, and Ranatra chinensis |
| (4) Present on the I segment: Ambrysus occidentalis and Helotrephes semiglobosus |
| (5) Present on the II segment: Hydrocyrius colombiae, Lethocerus deyrollei, and Tanycricos longiceps, |
| (6) Present on the III segment: Gelastocoris oculatus, Nerthra nepaeformis, N. macrothorax, and Corixoidea |
| (7) Present on the I and IV segments: Hydrotrephes visayasensis |
| (8) Absent: Aphelocheirus variegatus, A. aestivalis, Cheirochela feana, Gestroiella limnocoroides, Coptocatus oblongulus, Coptocatus kinabalu, Laccocoris hoogstraali, Heleocoris humeralis, Limnocoris lutzi, Cryphocricos hungerfordi, Ilyocoris cimicoides, Pelocoris femoratus, Macrocoris rhantoides, Naucoris maculatus, Neomacrocoris handlirschi, Paraplea frontalis, Plea minutissima, Hydrotrephes balnearius, Tiphotrephes indicus, Buenoa uhleri, and Nychia Sappoho |
| (?) Lack of data: Potamocoridae |
|
| K8. Dorsal hairs, proprioceptive sensilla; location and number | (0) Long, one pair on the dorsal side of the II segment; Mesovelia furcata |
| (1) Short, one pair on the dorsal side of the II segment; remaining nepomorphan species |
| (2) Long, three pairs on the dorsal side of the II segment; Nerthra nepaeformis and N. macrothorax |
| (3) Dispersed (III pairs of various lengths); Limnocoris lutzi |
| (4) Two pairs, short; Paraplea frontalis and Plea minutissima |
| (5) Lack of proprioceptive sensillum; corixoids species |
| (?) Lack of data; Potamocoridae |
|
| K9. Ventral hairs, proprioceptive sensilla; location and number | (0) One pair present on the ventral side (II segment); Mesovelia furcata, Belostoma flumineum, Deinostoma dilatatum, Gestroiella limnocoroides, Ambrysus occidentalis, Paraplea frontalis, Plea minutissima, Helotrephes semiglobosus, Hydrotrephes visayasensis, Hydrotrephes balnearius,Tiphotrephes indicus |
| (1) Lack of proprioceptive sensillum; corixoids species and the remaining nepomorphan species |
|
| K10. Squamiforme sensillum | (0) Absent; Mesovelia furcata and most of the nepomorphans |
| (1) Present; only in Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, and Nepa cinerea |
| (?) Lack of data; Potamocoridae |
|
| K11. Trichobothrium sensillum | (0) Absent; Mesovelia furcata and most of the nepomorphans |
| (1) Present; Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, and Nepa cinerea |
|
| K12. Basiconic sensillum | (0) Absent; Mesovelia furcata and most of the nepomorphans |
| (1) Present; Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, and Nepa cinerea |
| (?) Lack of data; Potamocoridae |
|
| K13. Club-like sensillum | (0) Absent; Mesovelia and most of the nepomorphans |
| (1) Present; Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, and Nepa cinerea |
| (?) Lack of data; Potamocoridae |
|
| K14. Paddle-like sensillum | (0) Absent; Mesovelia furcata and most of the nepomorphans |
| (1) Present; Cercotmetus asiaticus, Ranatra chinensis, and R. linearis |
| (?) Lack of data; Potamocoridae |
|
| K15. Cupola-shaped sensillum | (0) Absent; Mesovelia furcata and most of the nepomorphans |
| (1) Present; Belostoma flumineum, Deinostoma dilatatum, Appasus major, Hydrocyrius colombiae, Lethocerus deyrollei, Ochterus marginatus, Ochterus piliferus, Gelastocoris oculatus, Nerthra nepaeformis, N. macrothorax, Aphelocheirus variegatus, and A. aestivalis |
| (?) Lack of data; Potamocoridae |
|
| K16. Peg sensillum | (0) Absent; Mesovelia furcata, Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, Nepa cinerea, Cercotmetus asiaticus, Ranatra chinensis, R. linearis, Limnocoris lutzi, Cryphocricos hungerfordi, Ambrysus occidentalis, Ilyocoris cimicoides, Pelocoris femoratus, Macrocoris rhantoides, Naucoris maculatus, Neomacrocoris handlirschi, Namtokocoris siamensis, Paraplea frontalis, Helotrephes semiglobosus, Hydrotrephes visayasensis, Hydrotrephes balnearius, Tiphotrephes indicus, Anisops camaroonensis, A. sardea, Buenoa uhleri, Notonecta glauca, Enithares bergrothi, and Nychia sappho |
| (1) Present; Belostoma flumineum, Deinostoma dilatatum, Appasus major, Hydrocyrius colombiae, Lethocerus deyrollei, Ochterus marginatus, O. piliferus, Gelastocoris oculatus, Nerthra nepaeformis, N. macrothorax, Aphelocheirus variegatus, A. aestivalis, Cheirochela feana, Gestroiella limnocoroides, Coptocatus oblongulus, C. kinabalu, Laccocoris hoogstraali, Helocoris humeralis, and corixoids species |
| (?) Lack of data; Potamocoridae |
|
| K17. Finger-like sensillum | (0) Absent; Mesovelia furcata and most of the nepomorphans |
| (1) Present; Gelastocoris oculatus and G. bufo |
| (?) Lack of data; Potamocoridae |
|
| K18. Freniale-like sensillum | (0) Absent; Mesovelia and most of the nepomorphans |
| (1) Present; Gelastocoris oculatus and G. bufo |
| (?) Lack of data; Potamocoridae |
|
| K19. Chaetica sensillum with a bisected tip | (0) Absent; Mesovelia furcata and most of the nepomorphans |
| (1) Present; Nerthra nepaeformis, N. macrothorax |
| (?) Lack data; Potamocoridae |
|
| K20. Star-like sensillum | (0) Absent; Mesovelia furcata and most of the nepomorphans |
| (1) Present; Aphelocheirus variegatus and A. aestivalis |
| (?) Lack of data; Potamocoridae |
|
| K21. Multilobed sensillum | (0) Absent; Mesovelia furcata and some of nepomorphans |
| (1) Present; Limnocoris lutzi, Cryphocricos hungerfordi, Ambrysus occidentalis, Ilyocoris cimicoides, Pelocoris femoratus, Macrocoris rhantoides, Naucoris maculatus, Neomacrocoris handlirschi, and Namtokocoris siamensis |
| (?) Lack of data; Potamocoridae |
|
| K22. Ribbon-like sensillum | (0) Absent; Mesovelia furcata and most of the nepomorphans |
| (1) Present; corixoids species |
| (?) Lack of data; Potamocoridae |
|
| K23. Trichoid sensillum (TRS) on the dorsal side of the IV segment | (0) Present, short: Mesovelia furcata and Tiphotrephes indicus |
| (1) Present, short and long: Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, Nepa cinerea, Cercotmetus asiaticus, Ranatra chinensis, Belostoma flumineum, Deinostoma dilatatum, Appasus major, Hydrocyrius colombiae, Limnogeton fieberi, Lethocerus deyrollei, Helotrephes semiglobosus, Hydrotrephes visayasensis, H. balnearius, Anisops camaroonensis, A. sardea, Buenoa uhleri, Enithares bergrothi, and Nychia sappho |
| (2) Present, long: Paraplea frontalis and Notonecta glauca |
| (3) Absent: Ochterus piliferus, O. marginatus, Gelastocoris oculatus, Nerthra nepaeformis, N. macrothorax, Aphelocheirus variegatus, A. aestivalis, Cheirochela feana, Gestroiella limnocoroides, Coptocatus oblongulus, C. kinabalu, Tanycricos longiceps, Laccocoris hoogstraali, Heleocoris humeralis, Limnocoris lutzi, Cryphocricos hungerfordi, Ambrysus occidentalis, Ilyocoris cimicoides, Pelocoris femoratus, Macrocoris rhantoides, Naucoris maculatus, Neomacrocoris handlirschi (K23 invisible?), Namtokocoris siamensis, and corixoids species |
| (?) Lack of data: Potamocoridae |
|
| K24. Trichoid sensilla on the lateral side of the IV segment | (0) Absent: Mesovelia furcata, Belostoma flumineum, Deinostoma dilatatum, Appasus major, Hydrocyrius colombiae, Limnogeton fieberi, Lethocerus deyrollei, Ochterus piliferus, O. marginatus, Gelastocoris oculatus, Nerthra nepaeformis, N. macrothorax, Aphelocheirus variegatus, A. aestivalis, Cheirochela feana, Gestroiella limnocoroides, Coptocatus oblongulus, C. kinabalu, Tanycricos longiceps, Laccocoris hoogstraali, Heleocoris humeralis, Limnocoris lutzi, Cryphocricos hungerfordi, Ambrysus occidentalis, Ilyocoris cimicoides, Pelocoris femoratus, Macrocoris rhantoides, Naucoris maculatus, Neomacrocoris handlirschi, Namtokocoris siamensis, Helotrephes semiglobosus, Hydrotrephes visayasensis, H. balnearius, Tiphotrephes indicus, Anisops camaroonensis, A. sardea, Buenoa uhleri, Notonecta glauca, Enithares bergrothi, Nychia sappho, corixoids species, and Pleidae |
| (1) Present: Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, Nepa cinerea, Cercotmetus asiaticus, and Ranatra chinensis |
| (?) Lack of data: Potamocoridae |
|
| K25. Trichoid sensillum on the ventral side of the IV segment | (0) Present, short: Mesovelia furcata, Ochterus piliferus, O. marginatus, Gelastocoris oculatus, Nerthra nepaeformis, N. macrothorax, Aphelocheirus variegatus, A. aestivalis, and Tiphotrephes indicus |
| (1) Present short and long: Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, Nepa cinerea, Cercotmetus asiaticus, Ranatra chinensis, Belostoma flumineum, Deinostoma dilatatum, Appasus major, Hydrocyrius colombiae, Limnogeton fieberi, Lethocerus deyrollei, Cheirochela feana, Gestroiella limnocoroides, Coptocatus oblongulus, C. kinabalu, Tanycricos longiceps, Laccocoris hoogstraali, Heleocoris humeralis, Limnocoris lutzi, Cryphocricos hungerfordi, Ambrysus occidentalis, Ilyocoris cimicoides, Pelocoris femoratus, Macrocoris rhantoides, Naucoris maculatus, Neomacrocoris handlirschi, Namtokocoris siamensis, Hydrotrephes visayasensis, H. balnearius, Anisops camaroonensis, A. sardea, Notonecta glauca, and Nychia sappho |
| (2) Present, long: Paraplea frontalis, Plea minutissima, Helotrephes semiglobosus, Buenoa uhleri, and Enithares bergrothi |
| (3) Absent: corixoids species |
| (?) Lack of data: Potamocoridae |
|
| K26. Trichoid sensillum on the dorsal side of the third segment | (0) Absent: Mesovelia furcata, Curicta granulosa, Borborophyes mayri, Laccotrephes japonensis, Nepa cinerea, Cercotmetus asiaticus, Ranatra chinensis, Belostoma flumineum, Deinostoma dilatatum, Appasus major, Hydrocyrius colombiae, Limnogeton fieberi, Lethocerus deyrollei, Ochterus piliferus, O. marginatus, Gelastocoris oculatus, Nerthra nepaeformis, N. macrothorax, Aphelocheirus variegatus, A. aestivalis, Paraplea frontalis, Plea minutissima, Helotrephes semiglobosus, Hydrotrephes visayasensis, H. balnearius, Tiphotrephes indicus, Anisops camaroonensis, A. sardea, Notonecta glauca, Buenoa uhleri, Enithares bergrothi, Nychia sappho, and corixoids species |
| (1) Present, short: Coptocatus oblongulus, C. kinabalu, Tanycricos longiceps, and Limnocoris lutzi |
| (2) Present, short and long: Cheirochela feana, Gestroiella limnocoroides, Laccocoris hoogstraali, Heleocoris humeralis, Ambrysus occidentalis, Pelocoris femoratus, Macrocoris rhantoides, and Ilyocoris cimicoides |
| (3) Present, long: Cryphocricos hungerfordi, Naucoris maculatus, Namtokocoris siamensis, and Neomacrocoris handlirschi |
| (?) Lack of data: Potamocoridae |
|
| K27. Elongated plate sensillum | (0) Present; Mesovelia furcata |
| (1) Absent: all species of Nepomorpha |
|
| K28. Pit sensilla and their distribution | (0) Pit sensillum absent; Mesovelia furcata and corixoids species |
| (1) Pit sensillum present and localised rather laterally; all species of Nepidae and Belostomatidae |
| (2) Pit sensilla placed centrally; Ochterus piliferus, O. marginatus, Gelastocoris oculatus, Nerthra nepaeformis, N. macrothorax, Aphelocheirus variegatus, A. aestivalis, Anisops cameroonensis, A. sardea, Notonecta glauca, Buenoa uhleri, Enithares bergrothi, Nychia sappho, Cheirochela feana, Gestroiella limnocoroides, Coptocatus oblongulus, C. kinabalu, Tanycricos longiceps, Limnocoris lutzi, Laccocoris hoogstraali, Heleocoris humeralis, Cryphocricos hungerfordi, Ambrysus occidentalis, Pelocoris femoratus, Macrocoris rhantoides, Ilyocoris cimicoides, Naucoris maculatus, Namtokocoris siamensis, Neomacrocoris handlirschi, Paraplea frontalis, Plea minutissima, Helotrephes semiglobosus, Hydrotrephes visayasensis, H. balnearius, and Tiphotrephes indicus |
| (?) Lack of data; Potamocoridae |
|
| K29. Types and distribution of apical chemosensilla | (0) Peg sensilla placed centrally; Mesovelia furcata |
| (1) Papillae sensilla (PAS1) distributed over the tip of the labium; all species of the Nepidae and Belostomatidae, and Nerthrinae (Nerthra nepaeformis and N. macrothorax), |
| (2) Papillae sensilla (PAS2) distributed over the tip of the labium; Ochterus piliferus, O. marginatus, Gelastocoris oculatus, Aphelocheirus variegatus, A. aestivalis, Anisops camaroonensis, Anisops sardea, Notonecta glauca, Buenoa uhleri, Enithares bergrothi, Nychia sappho, Cheirochela feana, Gestroiella limnocoroides, Coptocatus oblongulus, Coptocatus kinabalu, Tanycricos longiceps, Limnocoris lutzi, Laccocoris hoogstraali, Heleocoris humeralis, Cryphocricos hungerfordi, Ambrysus occidentalis, Pelocoris femoratus, Macrocoris rhantoides, Ilyocoris cimicoides, Naucoris maculatus, Namtokocoris siamensis, Neomacrocoris handlirschi, Paraplea frontalis, Plea minutissima, Helotrephes semiglobosus, Hydrotrephes visayasensis, Hydrotrephes balnearius, Tiphotrephes indicus, and corixoids species |
| (?) Lack of data; Potamocoridae |
|
| K30. The number of apical chemosensilla | (0) Four to seven; Mesovelia furcata |
| (1) Eight to 14 pairs; most species of the Nepomorpha |
| (2) More than 15; corixoids species |
| (?) Lack of data; Potamocoridae |
|
| K31. Types of the labial tip | (0) Smooth; Mesovelia furcata, all species of the Nepidae and Belostomatidae, and Nerthrinae (Nerthra nepaeformis and N. macrothorax) and Diaprepocoris zealandiae |
| (1) Folded; Ochterus piliferus, O. marginatus, Gelastocoris oculatus, Aphelocheirus variegatus, A. aestivalis, Anisops camaroonensis, Anisops sardea, Notonecta glauca, Buenoa uhleri, Enithares bergrothi, Nychia sappho, Cheirochela feana, Gestroiella limnocoroides, Coptocatus oblongulus, C. kinabalu, Tanycricos longiceps, Limnocoris lutzi, Laccocoris hoogstraali, Heleocoris humeralis, Cryphocricos hungerfordi, Ambrysus occidentalis, Pelocoris femoratus, Macrocoris rhantoides, Ilyocoris cimicoides, Naucoris maculatus, Namtokocoris siamensis, Neomacrocoris handlirschi, Paraplea frontalis, Plea minutissima, Helotrephes semiglobosus, Hydrotrephes visayasensis, H. balnearius, Tiphotrephes indicus, and some of the corixoids species |
| (?) Lack of data; Potamocoridae |
|
| K32. Distribution of mechnosensilla | (0) Less numerous sensilla, grouped and unevenly arranged; Mesovelia |
| (1) Numerous sensilla, grouped and unevenly arranged; all Belostomatidae |
| (2) Densely and evenly arranged sensilla; all Nepidae, Gelastocoridae, and Ochteridae |
| (3) Less numerous and numerous, evenly arranged sensilla; all Aphelocheiridae and Naucoridae |
| (4) Not numerous and unevenly scattered sensilla; Notonectidae, Pleidae, and Helotrephidae |
| (5) Very numerous sensilla arranged in three transverse bands; Diaprepocoridae |
| (6) Very numerous sensilla arranged in five transverse bands; Micronectidae |
| (7) Very numerous sensilla arranged in six to seven transverse bands; Corixinae and Stenocorixinae |
| (8) Numerous sensilla scattered unevenly on the labial surface; Cymatiainae |
| (?) Lack of data; Potamocoridae |
|
| K33. Shape of the apical ventral plate | (0) Oval shaped; Mesovelia furcata, Nepidae, Ochteridae, Aphelocheiridae, Limnocorinae, Helotrephidae, Corixoidea |
| (1) Palm shaped; Belostomatidae |
| (2) Slim palm shaped; Nerthrinae |
| (3) Triangular; Gelastocorinae and Pleidae |
| (4) Rectangular; Cheirochelinae, Laccocorinae, Cryphocricinae, and Naucorinae |
| (5) Trapezoidal; Notonectidae |
| (?) Lack of data; Potamocoridae |
|
| K34. Shape of the intercalary sclerites | (0) Large plates (four) overlapping the dorsal and ventral side of the labium; Mesovelia furcata |
| (1) Two plates placed dorsally, do not reach to the lateral side; Nepidae and Belostomatidae |
| (2) Small flaps situated in the middle of the dorsal side; Ochteridae and Gelastocorinae |
| (3) Subtriangular shaped, does not overlap the lateral side; Nerthrinae |
| (4) Subtriangular shaped, overlaps the lateral side; Aphelocheiridae |
| (5) Wide, short flaps with a distinct membrane at the base; Cheirochelinae, |
| (6) Wide, short flaps with a slightly distinct membrane at the base; Limnocorinae and Cryphocricinae |
| (7) Severely reduced flaps; the membrane is not visible; Laccocorinae, Naucorinae, and Notonectidae |
| (8) Lack of intercalary sclerites; Pleidae, Helotrephidae, Potamocoridae, and Corixoidea |
|
| K35. Stylet groove of the first segment | (0) Open; Mesovelia furcata, Nepidae, Belostomatidae, Aphelocheiridae, Naucoridae, Pleidae, Helotrephidae, and Notonectidae |
| (1) Closed; Ochteridae and Gelastocoridae |
| (2) Absent (= lack of segment); Corixoidea |
| (?) Lack of data; Potamocoridae |
|
| K36. Shape of the first segment | (0) Ring shaped, well developed on the dorsal side (medium length, wide); Mesovelia furcata, Belostomatidae, Gelastocorinae, Ochteridae, Aphelocheiridae, and Notonectidae |
| (1) Ring shaped, weakly developed on the dorsal side (short, narrow); Potamocoridae, Naucoridae, Helotrephidae, and Pleidae |
| (2) Reduced on the dorsal side (trace of the segment); Nepidae |
| (3) Subtriangular with a deep incision (in); Nerthrinae |
| (4) Lack of the segment; Corixoidea |
|
| K37. The shape of the second segment, dorsally | (0) The dorsal surface is not divided; Mesovelia furcata, Nepidae, Belostomatidae, Nerthrinae, Gelastocorinae, and Ochteridae |
| (1) The dorsal surface is divided into a triangular plate, flat; Aphelocheiridae, Potamocoridae, Cheirochelinae, Laccocorinae, Cryphocricinae, Naucorinae, Buenoa uhleri, Enithares bergrothi, Nychia sappho, Anisops camaroonensis, and Anisops sardea |
| (2) The dorsal surface is divided into a triangular plate with a convex plate; Limnocoris lutzi |
| (3) The dorsal surface is divided into a triangular plate with the nodule; Notonecta glauca |
| (4) The dorsal surface is divided into a triangular plate with a large nodule; Pleidae and Helotrephidae |
| (5) Lack of the segment; Corixoidea |
|
| K38. The style groove on the dorsal side of the second segment | (0) Closed along the whole length of the segment; Mesovelia furcata, Gelastocoridae, Ochteridae, and Aphelocheiridae |
| (1) Without a clear boundary up to the middle of the segment; Nepidae and Belostomatidae |
| (2) Open up to the middle of the segment Naucoridae, Notonectidae, Helotrephidae and Pleidae, and Potamocoridae |
| (3) Lack of the second segment; Corixoidea |
|
| K39. The shape of the second segment, laterally | (0) The lateral surface smooth; Mesovelia furcata and the remaining Nepomorpha |
| (1) The lateral surface with the winged plate; Limnocoris lutzi |
| (2) lack of the second segment; Corixoidea |
|
| K40. The length of the second segment | (0) Short; Mesovelia furcata and the some species of the Nepomorpha |
| (1) Long; Hydrocyrius colombiae, Belostoma bakeri, Belostoma flumineum, Deinostoma dilatatum, and Limnogeton fieberi |
| (2) Reduced (or short ventrally); Corixoidea |
|
| K41. The length of the third segment | (0) Long; Mesovelia furcata, Ochteridae, Aphelocheiridae, and Corixoidea |
| (1) Shorter; remaining species of the Nepomorpha |
|
| K42. The length of the fourth segment | (0) Short; Mesovelia furcata and remaining species of the Nepomorpha |
| (1) Long; Helotrephidae |
| (2) Very short; Corixoidea |
|
| K43. The midventral condyle on the I segment | (?) Lack of data; Mesovelia furcata and Potamocoridae |
| (0) Present; Nepidae, Belostomatidae, Gelastocorinae, Ochteridae, Aphelocheiridae, Naucoridae, Pleidae, Helotrephidae, Notonectidae |
| (1) Absent; Nerthrinae and Corixoidea |
|
| K44. The midventral condyle on the III segment | (0) Present; Mesovelia furcata, Nepidae, Belostomatidae, Cheirochelinae (4 species), and Corixoidea |
| (1) Absent; Gelastocoridae, Ochteridae, Aphelocheiridae, Tanycricos longiceps (Cheirochelinae), Cryphocricinae, Limnocorinae, Naucorinae, Pleidae, Helotrephidae, and Notonectidae |
| (?) Lack of data; Potamocoridae and Laccocorinae |
|
| K45. The midventral condyle on the IV segment | (0) Absent; Mesovelia furcata, Nepidae, Belostomatidae, Corixoidea, Gelastocoridae, Ochteridae, Aphelocheiridae, and Cheirochelinae |
| (1) Present; Cryphocricinae, Limnocorinae, Naucorinae, Pleidae, Helotrephidae, and Notonectidae |
| (?) Lack of data; Potamocoridae and Laccocorinae |
|
| K46. Dorsal articulation between the second and third segments | (0) Band shaped; Mesovelia furcata, Nepidae, Belostomatidae, Gelastocorinae, Aphelocheiridae, Potamocoridae, Naucoridae and Notonectinae, and Potamocoridae |
| (1) Distinct condyle present; Ochteridae |
| (2) Long and folded membrane; Nerthrinae |
| (3) Three cornered; Pleidae and Helotrephidae |
| (?) Lack data; Corixoidea |
|
| K47. The shape of the labium | (0) Tubular long; Mesovelia furcata and most species of the Nepomorpha |
| (1) Triangular and short; corixoids species |
|
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