Alfonsoperla flinti, McLellan & Zwick, 2007

McLellan, Ian D. & Zwick, Peter, 2007, New Species Of And Keys To South American Gripopterygidae (Plecoptera), Illiesia 3 (4), pp. 20-42 : 24-27

Alfonsoperla flinti gen. n., sp. n.

( Figs. 6 ‐ 17 , 71)

Paragripopteryginae ( Teutoperla ?) Larventyp X Illies, 1963: 195, fig. 24.

Material examined. Holotype ♂, Chile, Arauco, San Alfonso above Caramavida, 16 ‐ 17 October 1969, OSF & GB ( USNM) . Paratypes: ♂ and ♀ and 3 paratype larvae, Chile, Malleco, Pino Hachado , 1480 m, 38°39 ʹ S; 70°58 ʹ W, 8 ‐ 9 January 1994, CMF & OSF ( USNM); 1m (with everted conical penis) , 1♀, Argentina, Neuquen, Lago Lolog, 40°02 ʹ S; 71°24 ʹ W, Quebrada, 19 km N of San. Martin del Los Andes, 1 ‐ 3 January 1994, CMF, OSF ; 1♂, Chile, Biobio / Malleco, Volcan Callaquen, 5 ‐ 7 February 1959, LEP . 1♂, Argentina, Neuquen, Rio Litran, 5 km. N. Lago Alumine 1 March 1978 C. MF & OSF ; 2?, Chile, Malleco, Nahuelbuta , bog outlet, 37°47 ʹ S; 73°01 ʹ W, 16 ‐ 19 December 1993, Malaise trap, CMF & OSF ; 1♀, Chile, Palena, Rio Ventisquero , 16 km S Pto.Cardenas, 100 m, 23 ‐ 24 January 1987, CMF & OSF ; 1♀, Chile, Nuble, El Purgatorio, 3 March 1968, OSF, MLP , 1♀, Argentina, Neuquen, brooklet above Pucara, 1 February 1974, OSF ; 1♂, 1♀, Chile, Nuble, Las Cabras, Cordillera Chillan, 8 ‐ 15 February 1959, LEP. All paratypes ( USNM) . Additional material: 8 LA, Chile, Nuble, Las Trancas , 1300 m, 21km E Recinto, high waterfall ex moss, 17 January 1979, MD , DD, BA; 9 LA (1 small), Chile, Nuble, Las Trancas , 1300 m, 21km E Recinto, high waterfall, ex moss, 17 January 1979, MD & DD & BA; 3 LA, Argentina, Neuquen, cascades, 6 km N Lago Alumine 1100 m, 3 February 1987, CMF & OSF , 1 LA, Chile, Osorno, stream near the Carabino Post in Antillanca , 12 December 1972, MLP ; 1 LA, Argentina, Neuquen, Ao Punameco, NW Lago Alumine , 1 March 1978, CMF & OSF ; 1 LA, Argentina, Neuquen, Ao Punameco, NW Lago Alumine , 1 March 1978, CMF & OSF .

Dimensions. Male: body length 7.0; forewing 8.0; antenna 5.0. Female: body length 9.0; forewing 9.5; antenna 5.0. Larva (last instar female): body length 8.5; antenna 3.0; cercus 1.7.

Adult. A medium sized stonefly. Head strongly deflexed, narrowed towards down ‐ turned mouthparts. Epicranial suture deeply grooved. Area between 3 distinct ocelli appears raised. Apical segment of maxillary palpus 3X length of penultimate segment. Pronotum rectangular, twice as wide as long, with raised anterior and posterior margins and a paramedian callus on disk. Brown to dark brown with pale stripe along midline and around perimeter. Legs without tibial spurs. Both wings with Rs and Cu1 forks and 6 anal veins in hind wing ( Fig. 6 ). Cerci downcurved, with about 10 ‐ 12 segments, basal one long.

Male genitalia ( Figs. 7 ‐ 9 ). Sternite 9 produced into wide, shallowly bilobed subgenital plate. Tergite 10 central sclerite curved downwards at half length to fit neatly between arms of epiproct base. Medially on rounded hind margin of tergite 10 is a minute cone shaped posterior sclerite. Arms of epiproct curve down and posteriorly, then join and curve upwards and posteriorly, terminating in a downcurved sharp tip. Paraprocts large, about as long as cerci, broadly falcate, inner face from base to about half length forms a triangular membranous sheet. Membranous penis inside sternite 9, visible only in cleared specimens. The everted penis appears relatively dark, apparently through tissue pushed into it by body fluid pressure. It is a large pointed cone slightly curved up between the paraproct bases, lying below the epiproct hook and is partly divided longitudinally by a lateral fold ( Fig. 9 ). A tiny gonopore apparently at tip of slightly longer anterior part. A small triangular wing embracing base of paraproct observed only on the left side of body of the single specimen with everted penis.

Female genitalia. ( Fig. 10 ). Sternite 8 with well developed subgenital plate, with 2 lateral dark bands, tapers to a rounded or double pointed tip extending on to sternite 9. Subanal lobes slender, pointed. Cerci short, of 12 segments. Tip of tergite 10 produced, rounded.

Larva. ( Figs. 11 ‐ 17 ). Short, stout, hairless and dusty brown. Surface matt because of numerous shallow pupillate punctures.

Head curved down, with shallow central depression between ecdysial suture and indistinct ocelli. Head capsule much narrowed from wide base to narrow front i.e. wedge shaped, genae in front view visible as flat surfaces below and in front of eyes and antennal foramen. Clypeus and labrum narrow. Mandible base ( Fig. 13 , stippled) prominently exposed. Mandibles ( Fig. 17 ) exceptionally flat, their long apices blade ‐ like, the sharp serrate edges of the pair interdigitate. Base of mandible with distinct setal rosette, mola far from mandible base. Left mola serrate anteriorly, right mola concave. Maxillae ( Fig. 16 ) long, with strongly elbowed base often quite visible in dorsal view; apparently, the maxilla can reach far forward. Maxillary palpus 4 ‐ segmented, apex of last segment soft, sometimes folded inward. Galea and lacinia unusually slender. Galea with apical rosette of sensilla, lacinia with few narrow well sclerotised apical teeth and a series of translucent fairly wide subterminal setae. Glossae shorter than simple paraglossae, with apical hair rosette ( Fig. 15 ). 2 nd segment of labial palpus medially swollen and strongly sclerotised. Hypopharynx inconspicuous and smooth.

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Pronotum subrectangular, wider than long; hind margins of mesonotum and metanotum convex. Thoracic tergites with relief of grooves and ridges whose outlines are difficult to define precisely because of rough matt surface and best seen in side view ( Fig. 12 ). A raised cone near base of wingpad on meso ‐ and metanotum.

Femora short and stout, dorsally crested, a raised spinulate hump mid ‐ dorsally. Tibia lacks spurs. Tarsal segments 1 and 2 both extremely short, segment 2 dorsally divided by narrow base of long 3 rd segment, ventral face of 3 rd tarsal segment spinose ( Fig. 14 ). Tergites and sternites of abdominal segments 1 and 2 divided, those of 3 incompletely divided, with anterior notch. Abdominal tergite 10 produced and pointed, more so in males. Subanal lobes narrow, long, triangular. Cerci short, about 18 segments. Retractable anal gill rosette of many filaments with subanal lobes able to close over it.

Remarks. The genus is named for the first locality from which the species was recorded. This species is dedicated to Carol and Oliver Flint who not only collected the types but also were responsible for collecting a sizeable portion of all the material we examined.

The male epiproct, paraprocts and the bilobed penis are characteristic of the Australian Dinotoperlinae and the wing venation with forks in Rs and Cu1 is characteristic of Trinotoperla and Illiesoperla in that subfamily. Lack of tibial spurs is uncommon but despite this the other characters point more to the inclusion of the genus in Dinotoperlinae rather than Gripopteryginae or Antarctoperlinae .

A young wingless larva of this species was illustrated and briefly described by Illies (1963), as “Larventyp X ( Teutoperla n. gen.?)”. The general shape, the spinose, dorsally raised femora (Illies’ text refers to ‘tibiae’ by mistake but his figure is correct), the pointed tergite 10, the long triangular paraprocts, the narrow maxilla and its 4 ‐ segmented palpi clearly indicate the conspecificity of his specimens with ours. Our interpretation is also confirmed by specimens in the Illies collection. The larva of this species was verified by dissection of a mature male larva.

Illies (1963) found the larvae in moss at the bottom of streams or on rocks. The present material additionally suggests that the larvae dwell in or at least near waterfalls. The exceptional shape of head capsule and mouthparts suggested some special food, but the fore ‐ gut of a single penultimate instar larva (from Neuquen Cascades) was filled with fine particulate matter, including many small diatom valves, fungal hyphae and spores, fragments of macrophyte tissue with tracheae, fine mineral particles, but no recognisable animal remains. The larva appears to be a gatherer, possibly obtaining its food from special microsites.

Figures

Figs. 6‐10. Alfonsoperla flinti gen. sp. n., adult. 6, pair of wings; 7, male abdominal tip, lateral; 8, same, dorsal; 9, same, oblique posterolateral view of specimen with everted penis, only bases of cerci shown; 10, female abdominal tip, ventral. Not to scale. bE, base of epiproct; E, epiproct; lP, left paraproct; P, penis; rP, right paraproct; S IX, sternite 9; T IX, T X, tergites 9, 10.

Figs. 11‐17. Alfonsoperla flinti gen. sp. n., larva. 11, last instar specimen, habitus; 12, fore body, lateral, legs and antennae not shown, mandible black; 13, head, frontal, mandibles stippled; 14, last tarsal segment; 15, labium, ventral; 16, left maxilla, ventral; 17, mandibles, ventral. Figs 11, 12 not to scale, 14‐17 to same scale. L, labium; M, mentum; Mx, maxilla.