Anisocentropus (Anisocentropus) tapenan, Oláh & Johanson, 2010

Oláh, János & Johanson, Kjell Arne, 2010, Description of 33 new species of Calamoceratidae, Molannidae, Odontoceridae and Philorheithridae (Trichoptera), with detailed presentation of their cephalic setal warts and grooves 2457, Zootaxa 2457 (1), pp. 1-128 : 36-39

Anisocentropus (Anisocentropus) tapenan , new species

Figs 73–77

This species is medium-sized, brown with a slightly darker brown and broad subapical transverse band on the forewings. It belongs to a diagnostic species-group having abbreviated gonocoxites. This new species is similar to A. malaisei described above from Myanmar. Anisocentropus tapenan is easily separated from A. malaisei due to the presence of a large and triangular lateral flank on the posterior margin of segment IX, not small and quadrangular as in A. malaisei ; the preanal appendages are depressed, not robust digitiform; and the gonocoxites have a pronounced hump on the subapical, mesal, short-spined lobe, being easily seen in ventral view. The 2 species have similar cephalic, cervical, thoracic and proepisternal structural units, grooves and setal warts.

Male (in alcohol). Medium-sized, small-eyed, brown body; legs, antennae and palps pale brown; wings brown with dark subapical, broad, transverse band. Head nearly rectangular in dorsal view, almost as long as broad. Ocelli absent. Tentorium slender, without dorsal arm; posterior arms very short, robust, ending in pair of large posterior tentorial pits; strong tentorial bridge without anteromesal or posteromesal protuberances; anterior tentorial arms robust posteriorly, slender anteriorly, without median lamellate processes; posterior half broad, ending in median keel in dorsal view and ventral corner in lateral view. Facial groove pattern modified, with plate-like flange, or rim, connecting anterior tentorial pits; theoretical lines separating frons and clypeus (frontogenal vertical groove) forming oblique, dorsal continuation from anterior tentorial pits; almost merging horizontally, with broad antennal grooves. Clypeogenal vertical grooves located ventrally of anterior tentorial pits, short, running slightly mesoventrad; well-visible pattern of plate-like flanges, frontogenal, and clypeogenal sutures forming complex of anterior tentorial arms (frontogenal septum). Small, poorly visible subantennal grooves sinuous, running almost horizontally between large frontogenal compact wart and palpifers; forming proximal articulation of palpi on stipes; subocular grooves not visible. Short, pronounced frontal groove present between antennae, joining vertexal medioantennal compact setose warts. Vertexal groove pattern reduced; large, anterad directed, rounded elevation dominating anterior half of vertex, reaching interantennal area, delineated laterally by extremely large membranous antennal sockets with corrugated or granulous surface near frontogenal compact setose wart; stem of epicranial groove (coronal groove) vestigial; usually permanent antennal and ocular grooves accompanied by occipito-postgenal grooves, partly merging anterad; tangential to very large occipital compact setal warts. Labrum long, quadrangular, with rounded apex, freely hanging, sparsely setose. Mandibles long, slightly pigmented, oriented laterad along each labrum; laciniae narrow, elongated, bearing few setae. Frontal setal warts absent on face. Frontal interantennal warts absent due to forward directed vertexal elevation. Pair of large, nearly triangular frontogenal compact setal warts present on posterior pregenae; obliquely or almost horizontally from frontogenal grooves; alone representing warts visible on face. Rounded, oriented forewardly, triangular elevation on vertex bearing fused vertexal medioantennal compact setose warts anteriorly on head; vertexal lateroantennal compact setal warts absent; antennal socket enlarged. Pair of small, rounded vertexal ocellar compact setose warts and pair of very small vertexal medioocellar diffuse setose warts present. One or 2 setae present centrally on vertex; obliquely located pair of large, ovoid occipital compact setose warts dominating on posterior half of vertex; pair of small postgenal compact warts visible between posterior section of ocular grooves and large occipital compact setose warts. Maxillary palps filiform; maxillary palp formula II-V-I-IV-VI-III. Scapes rounded, long, about half as long as head; pedicels 2/5ths as long as scapes. Two pairs pronotal warts present: pair of large, dorsal, transversely ovoid, elongate, narrow warts almost touching mesally; pair of small, rounded, warts located deep laterally and visible in lateral view. One pair of mesoscutal, diffuse warts in longitudinal line along entire mesoscutum, composed mostly of single, double and maximum triple setae in groups visible as weakly pigmented alveoli. Pair of mesoscutellar warts forming small, weakly pigmented rounded area with 7–9 setal alveoli. Minute, rounded setose wart located proximally above articulation of each cervical sclerite on proepisternum. Large, compact setal warts present mainly on membranous part of cervix, touching anterior arm of cervical sclerites. Lateral cervical sclerites forming narrow anterior arms articulated anteriorly to back of head, with occipital condyle present above posterior tentorial pits, and fusing with posterior cervical sclerites; posterior cervical sclerites forming narrow, elongated plates reaching prothoracic episternum, articulated to weakly sclerotized anteromedian band of prothoracic eusternum by thin ventral intercervical sclerites. Legs with symmetrical claws; spur formula 2, 4, 3; each foreleg posteroapical spur 2 times longer than its anteroapical spur; midlegs each with anterior spurs about 1/4th as long as its posterior spurs; each hind leg anteroapical spur about 1/8th as long as posteroapical spurs. Forewings: length 7.8 mm; membrane brown, with dark brown, broad, subapical band being darker at pterostigmal margin; R1 running free along its length; base of discoidal cell located proximally of midpoint of wing; forks I, II, III, IV, V present; crossveins h, sc-r, r, s, r-m, m, m-cu and cu2 present, crossveins cu1 and cu-a absent; postanal vein absent. Hind wings: R1 meeting R2; forks I, II, III, V present; fork I longer than fork II.

Male genitalia. Abdominal segment IX fused annularly, without longitudinal groove separating dorsal mesal and ventral parts; tergum twice as long as venter, dorsum and venter producing into narrow quadrangular process in lateral view; anterior margin of segment IX convex, directed ventrad; posterior margin with convex ventral half, with well developed, triangular, additional flank below preanal appendages. Antecosta weakly developed, forming narrow, marginal rim, equally thin along margin, without conspicuous external groove of antecostal suture; in dorsal view, tergum with small triangular mesal convexity, forming fading continuation towards segment X; spine row absent on posterior margins of segment IX; entire segment smoothly glabrous, except larger area on venter with sparse, scattered long setae. Intersegmental depression between segments IX and X gently sloping. Segment X much longer than gonocoxites and preanal appendages, forming broad hood with ventrad directed apical rim characterised by sinuous excavations visible in lateral, dorsal and ventral views, excavations forming tooth-like pattern on ventrad curving margin, 2 teeth clearly visible; apicoventral setose lobes reduced to setose, subapical surfaces or shallow protuberances; apicodorsal setose lobes with few tiny setae above middle of segment X. Dorsal interlobular gap U-shaped. Preanal appendages depressed in lateral view, digitiform in ventral and dorsal view; broader at mid-point, slightly tapering apicad. Gonocoxites without harpago, short triangular in lateral view, elongate and apically broadening in ventral view, with pronounced mesal, subapical hump of large protuberance covered with short and stout spines. Phallic apparatus forming curving tube; basal part slightly convex; ventral part concave, elongated sclerotized ventral apical lobe. Part of retracted phallicata visible above ventral lobe; phallotremal sclerite nearly invisible in lateral view; forming complex unit in membranous phallicata; phallotremal sclerite complex in ventral view, U-shaped, laterad curving corners. Thin ejaculatory duct reaching phallotremal sclerite complex.

Holotype male: SOLOMON ISLANDS: Guadalcanal Island, Tapenanje , 10–23.xii.1953, at light [J.D. Bradley & I. Rennell] – (B.M. 1954-222, NHML).

Distribution: Solomon Islands.

Etymology: Tapenan, after the type locality, Tapenanje.

Figures

FIGURES 73–77. Anisocentropus tapenan, new species, holotype. 73 — right forewing; 74 — genitalia, lateral; 75 — genitalia, ventral; 76 — phallus, lateral; 77 — phallus, ventral.