３－５ Diplocladius group （ventromental plate with setae）
return to Ｏｒｔｈｏｃｌａｄｉｉｎａｅ ｇｒｏｕｐ
Ｄｉｐｌｏｃｌａｄｉｕｓ Psectrocladius Rheocricotopus Synorthocladius Parorthocladius
| mentum ventromental plate |
antenna | SⅠ | other characteristics | |
| Diplocladius | 2 median teeth ,lateral teeth 6 pairs ventromental plate with long,, numerous setae |
5 segments, antennal ratio 1.7～2.3 | plumose | mandible; 4 inner teeth |
| Psectrocladius (flabvus type) |
dome shape , small concave at tip. lateral teeth 4 pairs. ventromental plate with few weak setae . |
5 segments , nomal | palmate with several teeth | apical tooth of mandible thin and long |
| Psectrocladius （sordidellus type) |
deeply concave at tip. ventromental plate triangule with long few setae |
5 segments , nomal | palmate with several teeth | mandible; 4 inner teeth |
| Rheocricotopus | median tooth with concave deeply ventromental plate oval with weak setae |
5 segments , nomal | bifid | mandible; 3 inner teeth |
| Synorthocladius | two median teeth long triangle. ventromental plate long , with dozens thin setae spread radially |
5 segments , 3rd segment more than two of times of 2nd segment. |
simple ,short | body: lateral sides of segment 5～9 with tuft of short setae. anal tubules long. |
| Parorthocladius | three median teeth long triangle. ventromental plate long , with dozens thin setae spread radially. |
5 segments, 3rd. segment shorter than 2nd. segment. |
simple ,short | body: lateral sides of segment 4～9 with tuft of short setae. anal tubules long. |
Diplocladius
Ｂｏｄｙ ｌｅｎｇｔｈ ５～１０mm. Living body color grayish green～brownish green. They
are distributed widely in the country, several kinds of larvae are found
.They inhabit in cool and clear , nomal ～ rapid flow.
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| Ventromental plate long, and with numerous long strong setae | ||
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・Antenna 5 segments, antennal ratio 1.7～ 2.3. Lauterborn's organ and style of tip of the 2nd segment remarkable. ・Median teeth of mentum two. Lateral teeth 6 pairs. Ventromental plate long, and with numerous long strong setae. ・Inner teeth of mandible 4. ・ＳⅠplumose.、ＳⅡlong, simple. ・Pecten epipharyngis large three lobes. ・Premandible broad, divided into two deeply at the tip. ・Anal setae 7. |
Psectrocladius
Ｂｏｄｙ ｌｅｎｇｔｈ ５～１０mm. Living body color yellowish green～dark green. They
are distributed widely in the country, several kinds of larvae are found
.They inhabit in cool and clear , still or running water.
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| Psectrocladius flavus tupe： whole mentun dome shape. small concave at the tip Laterl teeth 4 pairs. Ventromental plate with few weak setae. |
Psectrocladius sordidellus type：median tooth with concave deeply. Ventromental plate triangule with long few setae | |
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Psectrocladius sordidellus １：Antenna ２Mmentum, median tooth bifid、 Ventromental plate with numerous setae ３：Lubrum:: ＳⅠwith several coarse teeth ＳⅡsimple Pecten epipharyngis consisting of 3 separated plates. Premandible simple ４：Mandible ５：Maxilla ６：Head , dorosal side ７：Claws of posterior parapod ８：Claws of anterior parapod ９：Anal tubules １０：Anal setae; 2 long & 3 short setae |
| Psectrocladius flavus type.：Apical tooth of mandible longer than combined 3 inner teeth. | Psectrocladius sordidellus type |
Body ｌｅｎｇｔｈ ５～１０mm. Living body color light brown .They inhabit in the surface of storn or rock.. They distributed widely in the country. I caught 5～6 species.
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| Median teeth with or without a small tooth on both side. | Antenna and Mandible. Seta subdentalis with apical hook. |
Procercus with a small projection on the rear side. |
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１：Antenna :5 segments Lauterborn's organ and style on the apical of the 2nd. segment slightly large. ２：Mentum: With two medianteeth . Ventromental plate long oval with long numerous setae. ３：Lablum: ＳⅠbifid. ＳⅡthin simple. Pecten epipharyngis consisting of 3 separated plates. Premandible simple. ４：Mandible: with 3 inner teeth. Seta subdentalis with apical hook. ５：Maxilla ６：Procercus with or without small projection Anal setae 5. ７：Claws of anterior parapod ８：Claws of posterior parapod |
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Small size larvae up to 4 mm. grayish green～dark green. several species found in the country., live in sandy pebble river bed.
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| Mentum: long triangle with 2 median teeth and 4 pairs lateral teeth. Ventromental
plate with long setae tuft of 40 or more. |
Anal setae 4 long and 2 short. Anual tubules longer than 2 or 3 times of posterior parapod. | |
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| 2 strong setae and two small projections with 10 or more weak setae on the both side of the ５～９ abdominal segments . | Antenna with 4 segments, 3rd. segment more than two times of 2nd. segment length. Blade beyond the tip of 4th. segment. | Mandible: whole brown ,triangle, with 3 inner teeth. Seta subdentalis long and sharp., seta interna absent. ＳⅠ、ＳⅡsimple, short. Pecten epipharyngis 3 scales. |
Small soze larvae up to 4mm. They live in the river low water temperature .( River Hidaka, ukawa (Hokkaido), Saikawa (Nagano pref..)
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| Mentum with 3 equal size teeth forming apex and 4 pairs lateral teeth .Ventromental plate small . beard consisting of a tuft of long setae. | Mandible with 3 inner thhet, seta interna absent. | Antenna: with 5 segments, 2nd segment longer than 3rd-5th. segments. |
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・ .The form of mentum resembles one of Synorthocladius, but
it is deisive difference that the median teeth of mentum are three ・Ｓ,、ＳⅡ: short and thin, simple. ・Tufts with 10 or more weak setae on the both side of the 4～9 abdominal segments ・Anal setae 5～6 ・Anal tubules 1/2～1/3 of posterior parapod. |