Alisotrichia holzenthali, Santos, Allan Paulo Moreira, 2011

Santos, Allan Paulo Moreira, 2011, Four new species of the microcaddisfly genus Alisotrichia Flint (Trichoptera: Hydroptilidae) from southeastern Brazil, Zootaxa 3112, pp. 59-68 : 60-62

Alisotrichia holzenthali sp. nov.

( Figs. 1–8 )

Diagnosis. Alisotrichia holzenthali sp. nov. is included in the A. orophila Group based on male genitalia, which have a pair of dorsolateral processes bearing very long and spine-like setae on the dorsum of segment VIII. Among species of this group, A. holzenthali sp. nov. is more similar to A. cacaulandia and A. kanakua Harris & Holzenthal, 1993 , based on the male genitalia, particularly the internal sclerotized plate apparently attached to segment IX ventrally and the elongate and tubular phallus. This new species can be distinguished from these species and others in the A. orophila Group by sinuous lateral sclerites on the dorsum of segment IX, which are ‘parenthesis-like’ ( Harris & Flint 2002) in A. kanukua and absent in A. cacaulandia ; by segment X narrow and rounded anteriorly and strongly truncate posteriorly, whereas in A. cacaulandia the segment X narrows to the apex and in A. kanukua the segment X is rectangular; and by a phallus with a pair of lateral flattened lobes at the apex, which are emarginated and curved laterad, whereas in both A. cacaulandia and A. kanukua the distal portion of the phallus is slender with the ejaculatory duct protruding apically and without lobes or processes. In addition, Alisotrichia holzenthali sp. nov. can be recognized by the color pattern of the forewings with small white spots on black.

Description. Male body. Length 2.0- 2.2 mm (n=8). General color black (dark brown in ethanol), with small white spots on forewings. Antennae each with 19 articles; scape enlarged, semicircular in anterior view ( Fig. 1 ), and with white setae; pedicel slightly longer than broad; flagellomeres short and setose; apical article tapering ( Fig. 1 ). Ocelli 2. Maxillary palpi each 5-articulated; labial palpi each 3-articulated. Mesoscutellum with transverse suture. Metascutellum almost rectangular. Tibial spurs 0,2,4. Fore- and hind wings with long dark brown and black setae, forewings with small white setae forming small spots. Abdominal segment VII without ventromesal process ( Fig. 2 ).

Male genitalia. Segment VIII with pair of dorsolateral processes each bearing 1 very long, spine-like seta ( Fig. 3 ); in ventral view, posterior margin slightly emarginated, with long setae laterally ( Fig. 2 ). Segment IX short and fused with segment X ( Fig. 3 ); anterior margin with pair of long, slender apodemes reaching segment V internally ( Fig. 2 ); in dorsal view, oval with characteristic sinuous lateral sclerites ( Fig. 3 ); reduced ventrally. Internal sclerotized plate, apparently attached to segment IX, with anterior portion projecting into pair of rods in ventral view ( Fig. 2 ), curved in lateral view ( Fig. 4 ); with elaborate sclerites mesally. Segment X short, membranous, narrow and rounded anteriorly, with posterior margin strongly truncate ( Figs. 2, 3 ). Subgenital plate indistinct. Inferior appendages absent. Phallus slender and tubular, with pair of flattened apical lobes which are emarginated and curved laterad ( Fig. 5 ); ejaculatory duct projecting apically ( Fig. 5 ).

Female body. Length 2.1-2.3 mm (n=9). General color as in male. Antennae each with 18 articles; scape simple. Ocelli 3. Other features of head and thorax as in male. Abdominal segment VI annular, without ventromesal process ( Fig. 6 ). Segment VII long, narrowing posteriorly; with elongate and setose mesal process dorsally ( Fig. 7 ); with plumose setae on ventral surface.

Female genitalia. Segment VIII short, with ring of long setae posteriorly ( Fig. 6 ). Segment IX short, narrowing posteriorly ( Figs. 6, 7 ). Segment X short, with pair of apical papillae ( Figs. 6, 7 ). Bursa copulatrix with elaborate folding anteriorly; posteriorly projecting into very long, rod-shaped sclerite ( Fig. 8 ).

Material examined. Holotype male. BRAZIL, Minas Gerais State, Santana do Riacho municipality, Cardeal Mota, Rio Cipó, Cachoeira Grande, 19°20’46.7”S 43°38’09.7”W, 21.iv.2010, A.P.M. Santos & D.M. Takiya leg. Paratypes. Same data except: 3 males, 3 females ( DZRJ / UMSP). Same data except: Rio Cipó, Cachoeira de Baixo, 19°20’33.2”S, 43°38’31.9”W, 750 m, 10-15.ii.1998, R.W. Holzenthal, H. Paprocki & J. Huisman leg., 1 male, 2 females ( UMSP). Same data except: Rio Cipó, Cachoeira de Baixo, 19°20’33.2”S, 43°38’31.9”W, 750 m, 22.iv.2010, A.P.M. Santos & D.M. Takiya leg., 3 males, 4 females ( DZRJ / MZSP).

Etymology. This species is named in honor of Dr. Ralph W. Holzenthal, who sent me specimens and identified them as a new species.

Distribution. Brazil: Minas Gerais State.

Biological notes. Specimens of A. holzenthali sp. nov. were collected during the day, while they actively ran on rock surfaces in large and fast flowing streams. The behavior of adults of A. holzenthali sp. nov. is very similar to that described for species of Byrsopteryx Flint, 1981 . Another remarkable similarity between this new species and Byrsopteryx species is the color pattern, black with small white spots, which when running, makes identifying them as Alisotrichia difficult.

Figures

FIGURES 1 – 5. Alisotrichia holzenthali sp. nov. 1: right male antenna, right lateral view; 2 – 5: male genitalia. 2: ventral view; 3: dorsal view; 4: left lateral view; 5: phallus, dorsal view.

FIGURES 6 – 8. Alisotrichia holzenthali sp. nov., female genitalia. 6: ventral view; 7: dorsal view; 8: bursa copulatrix, ventral view.