Isoperla of

Sandberg, John B., 2011, The Isoperla Of California (Plecoptera: Perlodidae); Larval Descriptions And A Key To 17 Western Nearctic Species, Illiesia 7 (22), pp. 202-258: 209-210

publication ID

http://doi.org/10.5281/zenodo.4760320

DOI

http://doi.org/10.5281/zenodo.4764104

persistent identifier

http://treatment.plazi.org/id/D27B87A3-FF96-F119-FF30-FCBC96D1FAF1

treatment provided by

Felipe

scientific name

Isoperla of
status

 

Key to the Isoperla of   California (including I. muir   and I. tilasqua   )

Mature Male Larvae

1 Lacinia submarginal setae ( Fig. 1a View Fig , Fig. 4g View Figs ) arranged in a close set row, extending past the subapical tooth (SAT) inner margin before the first gap between setae occurs ( Fig. 4h View Figs ) …..………………….…………………...... I. adunca  

1’ Lacinia submarginal row variable, group (A) setae a close set row, not extending past SAT inner margin ( Figs. 5g View Figs , 17g View Figs & 19g View Figs ); submarginal row continuous but setae separated by gaps as wide or wider than the width of setae at bases ( Fig. 13g View Figs ); or submarginal row interrupted by large gap between groups A & B ( Figs. 3g View Figs , 6-12g View Figs View Figs View Figs View Figs View Figs View Figs View Figs , 14-16g View Figs View Figs View Figs & 18g View Figs ) .......................................................................... 2

2 Lacinia submarginal row (A) with 2–7 closely spaced setae ( Figs. 5 View Figs g-h, 17g-h & 19g-h) omitting thin marginal seta (TMS); pronotum with thick comma shaped dark pigment bands near lateral margins of discs ( I. sobria   complex except I. miwok   ) ( Figs. 5b View Figs , 17b View Figs & 19b View Figs ) ................................................ 3

2’ Lacinia submarginal row (A) with 1 or 2 widely spaced setae ( Figs. 3 View Figs g-h, 6-16g-h & 18g-h) omitting (TMS); pronotum with ( I. miwok   ) or without comma shaped pigment bands ……… 5

3 Lacinia submarginal row (A) with 5–7 closely spaced setae ( Figs. 5 View Figs g-h); maxillary palp segments 2–3 with curved apically rounded setae ( Fig. 5e View Figs Inset); irregular shaped interocellar light area completely enclosed by dark pigment and known only from Domingo Spring, Plumas County, California …………………………….. I. baumanni  

3’ Lacinia submarginal row (A) with 2–5 closely spaced setae ( Figs. 17 View Figs g-h, 19g-h); basal segments 2–3 of maxillary palpi with long, thin, apically rounded or pointed setae; interocellar light area either enclosed or not completely enclosed by dark pigment; variable distribution ..…….…… 4

4 Basal segments 2–3 of maxillary palpi with long, thin, apically pointed setae ( Fig 17e View Figs Inset); interocellar light area usually an inverted V shape, completely within the three ocelli and enclosed by dark pigment ( Fig. 17a View Figs ); width of median longitudinal light band connecting light M shape to frontoclypeus approximately equal to posteromedian portion of light M shape ( Fig. 17a View Figs ) ……………………..…………………....… I. sobria  

4’ Basal segments 2–3 of maxillary palpi with long, thin, apically rounded setae ( Fig. 19e View Figs Inset); interocellar light area not an inverted V shape, usually extending past posterior ocelli to median posterior head capsule light area ( Fig. 19a View Figs ); width of median longitudinal light band connecting light M shape to frontoclypeus approximately half that of posteromedian portion of light M shape ( Fig. 19a View Figs ) ….................................. I. tilasqua  

5 Lacinia submarginal row (B) with 5–7 setae ( Fig. 13g View Figs ); first marginal seta (C) located under flaplike subapical tooth (SAT) basal inner margin ( Fig. 13h View Figs ), dorsal seta (DS) at base of SAT absent ………………………………………............. I. muir  

5’ Lacinia submarginal row (B) with 1–3 setae; first marginal seta (C) not under flap-like SAT basal inner margin; DS at base of SAT present ( Figs. 3 View Figs gh, 6-12g-h, 14-16g-h & 18g-h) ….……………..…. 6

6 Lacinia with first (closest to AT inner margin) submarginal seta (A) inserted closer to middle of subapical tooth base than to apical tooth inner margin ( Figs. 11 View Figs g-h) …………...………. I. miwok  

6’ Lacinia with first submarginal seta (A) inserted closer to base of apical tooth inner margin ( Figs. 3 View Figs g-h, 6-10g-h, 12g-h, 14-16g-h & 18g-h) …......... 7

7 Lacinia with 1–2 submarginal setae (A) less than half as stout at base as largest marginal setae (C), longitudinal striations weak or absent ( Figs. 14 View Figs gh); pronotum with checkerboard pigment pattern ( Fig. 14b View Figs ) ....................................................... I. pinta  

7’ Lacinia with 1–2 submarginal setae (A) half to nearly as stout at base as largest marginal setae (C), longitudinal striations usually present ( Figs. 3 View Figs g-h, 6-10g-h, 12g-h, 15-16g-h & 18g-h); pronotum without checkerboard pigment pattern ( Figs. 3a View Figs , 6-10a View Figs View Figs View Figs View Figs View Figs , 12a View Figs , 15-16a View Figs View Figs & 18a View Figs ) ….....................………. 8

8 Lacinia without dorsal surface setae (DSS), at most the last few marginal setae (C) form a short dorsal row ( Fig. 7f View Figs - arrow); ventral surface setae (D) concentrated on apical half, few posteriorly ……………………………………..….... I. denningi  

8’ Lacinia with dorsal surface setae (DSS) forming a long single row or dense, laterally protruding longitudinal band ( Figs. 3f View Figs , 6f View Figs , 8-12f View Figs View Figs View Figs View Figs View Figs , 15-16f View Figs View Figs & 18f View Figs ); ventral surface setae (D) scattered below marginal and submarginal setae or forming a dense longitudinal band, sometimes concentrated in posterior half …………………………………….. 9

9 Lacinia with 7–41 ventral surface setae (D) scattered below marginal or submarginal setae ( Figs. 3f View Figs , 6f View Figs , 9f View Figs & 12f View Figs ) …………………….....…… 10

9’ Lacinia with 41–110 ventral surface setae (D) forming dense longitudinal band below marginal or submarginal setae ( Figs. 8f View Figs , 10f View Figs , 15-16f View Figs View Figs & 18f View Figs ) ….………………...………………...……………….13

10 Lacinia with 7–14 ventral surface setae (D) ( Figs. 9f View Figs , 12f View Figs ) ….....…..…...……………...…..……..….… 11

10’ Lacinia with 17–41 ventral surface setae (D) ( Figs. 3f View Figs , 6f View Figs ) ……................……………........………..… 12

11 Fine silky setae sparse on dorsal surfaces of femora and tibia ( Fig. 20g View Figs ); interocellar area completely dark ( Fig. 9a View Figs ); length 9–10 mm ….…………………………………………. I. laucki  

11’ Fine silky setae sparse on dorsal surface of femora, numerous and continuous on tibia ( Fig. 20j View Figs ); interocellar area partially light ( Fig. 12a View Figs ); length 7–9 mm ………….....…….…… I. mormona  

12 Fine silky setae numerous and continuous on dorsal surfaces of femora and tibia ( Fig. 20a View Figs ); abdomen with median longitudinal thin dark pigment band ( Fig. 3d View Figs ) ………..…….…… I. acula  

12’ Fine silky setae sparse on dorsal surface of femora, numerous but not continuous on tibia ( Fig. 20d View Figs ); abdomen without median longitudinal dark pigment band ( Fig. 6d View Figs ) ………... I. bifurcata  

13 Pronotal discs mostly dark, each usually with small, light, reticulate markings along median dark pigment margins ( I. marmorata   complex) ( Figs. 8a View Figs , 10a View Figs & 16a View Figs ) …….....………………….…. 14

13’ Pronotal discs patterned, each with variable central light areas generally enclosed by dark pigment ( Figs. 15a View Figs , 18a View Figs ) ..……………………… 15

14 Dorsal head capsule light M shaped pattern variable, usually not connected to light frontoclypeus area by light longitudinal median band ( Figs. 8a View Figs , 16a View Figs ) .............. I. fulva   & I. roguensis  

14’ Dorsal head capsule light M shaped pattern variable, usually connected to light frontoclypeus area by light longitudinal median band ( Fig. 10a View Figs ) ………………….....…………….…… I. marmorata  

15 Fine silky setae numerous and continuous on dorsal surfaces of femora and tibia ( Fig. 20m View Figs ); faint M shaped light pattern on dorsum of head completely enclosed by dark pigment ( Fig. 15a View Figs ); pronotum pattern variable with small to large irregular shaped window-like light areas on each disc (small in Fig. 15b View Figs ), specimens with large window like light areas usually partially open along inner margins …..…… I. quinquepunctata  

15’ Fine silky setae sparse on dorsal surface of femora, numerous and continuous on tibia ( Fig. 20p View Figs ); M shaped light pattern on dorsum of head connected to unpigmented frontoclypeus by median light band ( Fig. 18a View Figs ); pronotum pattern less variable, with large irregular shaped window-like light areas on each disc ( Fig. 18b View Figs ), window-like light areas enclosed by dark pigment along inner margins.…………………... I. sordida