Antarctoperlinae, Enderlein, 1909

McLellan, Ian D. & Zwick, Peter, 2007, New Species Of And Keys To South American Gripopterygidae (Plecoptera), Illiesia 3 (4), pp. 20-42 : 29-31

Antarctoperlinae gen. sp. II

( Figs. 24 ‐ 29 )

Material examined. 2 LA, Argentina, Neuquen, Rio Litran, 5 km. N. Lago Alumine 1 March.1978 CMF & OSF ; 8 LA, Argentina, Neuquen, Ao. Purumeco, NW Lago Alumine 1 March 1978 CMF & OSF ; 1 LA, Chile, Malleco, small stream 20 km E. Liucura, 1750 m, 4 February 1987, CMF & OSF, (February 97 in LFS) ; 1 LA, Argentina, Neuquen, small stream, 10 km S. Pino Hachado , 4. February 1987, CMF & OSF, (February 97 in LFS) ; 4 LA, Chile, Malleco Prov., Cordillera de las Raices , 37 km E Curacautin, 5 ‐ 6 February 1979, 1100 m, DD, MD & DA (97 in LFS) ; 39 LA, Chile, Malleco, small stream, 9 km W Lonquimay, 5 February 1987, CMF & OSF (3 remain as duplicates in LFS) . 8 LA “9/12 o” among unsorted material in coll. Illies, locality and date unknown.

Dimensions. Larva (last instar): body length 12.5 ‐ 13.0; antenna 7.0; cerci 2.5.

Larva. Dark brown, muscle attachments on head and thorax darker. Scape and pedicel plus some flagellar segments (about segments 7 ‐ 12) darker brown than rest of antenna. Similarly, tip of first cercus segment and the next 6 ‐ 8 segments distinctly darker brown than rest of cercus. Clothed with short dark procumbent setae ( Fig. 25 ) except side edges of thorax and caudal edges of abdominal segments which have setal fringes as described below.

Head: Massive, dorsal face flat, occipital area strongly downcurved. Eyes large, no ocelli. Central depression shallow, indistinct. Unpaired cephalic suture long, branches initially diverging at right angle, then bent abruptly sidewards, meeting inner edge of eyes and curving forward alongside them, behind antennae. Frons descending stepwise to clypeus, labrum with large articulation membrane. Genae as high as the large antennal scape and cut off and rounded level with the scape. Mouthparts similar to Antarctoperlinae gen. sp. I. Antennae about half as long as body, scape large, pedicel dark, basally strongly constricted. Base of flagellum distinctly expanded, segments on wide part of flagellum very short and distinguished by rings of strong short setae whose tips curve back against flagellum; narrow distal segments almost twice longer than wide, hairs hardly noticeable.

Thorax. Nota flanged, the edges with a fringe of prominent setae with truncate tips. Pronotum as wide as head, wider than long, almost rectangular with a short blunt extension of the anterior angles. Wingpads short and triangular. Legs. Short, hind legs shorter than the abdomen and clothed dorsally with a few dark setae. Tibiae triangular with a sharp outer edge. Tarsi with the usual short segment 1 and 2 and large claws.

Abdomen short and wider medially, the segments are complete rings, their hind margins with a fringe of prominent dark setae. Hind margin of tergite 10 rounded. Subanal lobes each with a long pointed projection. Cerci short and threadlike, their extremities clothed with a ring of short setae.

Remarks. The short triangular wing pads probably indicate that some adults may be short winged. Both Antarctoperlinae gen.sp. I and II have a broad flanged thorax and long, almost straight paraproctal spines. The prominent pronotal corners and long setae of the abdominal hair fringes distinguish sp. I from sp. II. The latter has blunt corners of pronotum and short peg ‐ like setae in abdominal fringes.

Figures

Figs. 24‐29. Antarctoperlinae gen.sp. II, larva. 24, habitus; 25, detail of pronotal lateral margin; 26, hypopharynx, lateral; 27, same, dorsal; 28, rear part of an abdominal tergite, with surface pilosity and caudal setal fringe; 29, abdominal tip, lateral.