Chimarra biramosa Kimmins, 1957

Cartwright, David, 2020, A review of the New Guinea species of Chimarra Stephens (Trichoptera: Philopotamidae), Memoirs of Museum Victoria 79, pp. 1-49 : 28

Chimarra biramosa Kimmins, 1957

Figure 86

Chimarra biramosa Kimmins, 1957: 292 ; figs 4a, 5.—Neboiss, 1986: 108.— Cartwright, 2001: 225, figs 10–12, 16, 21.

Type material not seen. Holotype. Male, Solomon Islands, Guadalcanal Island, Tapenanje , 10–15 December 1953, J.D. Bradley ( BMNH).

Material examined. PNG. 1 male (in alcohol, specimen CT-333 partly figured), Western Highlands District, Pengi Creek, Bayer River Sanctuary, about 5° 31' S, 144° 11' E, lt tr, 16 June 1986, A. Wells ( NMV) .

Diagnosis. The males of C. biramosa and C. felkora Oláh can be separated from all other New Guinea species, by the branched inferior appendages, in lateral view. Chimarra felkora differs from C. biramosa in that the dorsal branch of the inferior appendage is strongly hooked, not straight or inclined as in C. biramosa .

Description (revised after Kimmins, 1957; Cartwright, 2001). General body colour and wings pale (faded) to brownish. Wings ( Kimmins, 1957: fig. 4A) similar to those of C. ukarumpana (fig. 7). Length of forewing: male 4.1–4.5 mm. Forewing with forks 1, 2, 3 and 5 present, Rs moderately sinuous or curved, moderately thickened, basad of discoidal cell ( Kimmins, 1957: fig. 4A); hind wing with forks 1, 2, 3 and 5 present.

Male. Segment IX anterior margin in lateral view, anteroventrally angular or sub-truncate (fig. 86; Kimmins, 1957: fig. 5A), ventral process short, basal to distal margin of segment IX (fig. 86), in lateral view, semi-triangular, apex subacute (fig. 86; more rounded distally in Kimmins, 1957: fig. 5A; Neboiss, 1986a: fig. p. 108), length about 0.6–0.7 width, preanal appendages, ovate (fig. 86; Kimmins, 1957: figs 5A, 5B). Segment X lateral lobes laterally compressed with sensilla not discerned, in lateral view, robust, apices slightly downturned (fig. 86; Kimmins, 1957: fig. 5A; Neboiss, 1986a: fig. p. 108), in dorsal view lateral lobes slender, apices acute, slightly in turned ( Cartwright, 2001: fig. 12; Kimmins, 1962: fig. 5B). Phallus with one slender spine included subapically and a larger emergent (asymmetric) spine more basally (fig. 86; Cartwright 2001: figs 10–12; Kimmins, 1957: fig. 5B). Inferior appendages branched, in lateral view, ventral branch directed nearly horizontally, dorsal branch directed almost vertically (fig. 86; Kimmins, 1962: fig. 5A; Neboiss, 1986a: fig. p. 108), in ventral view sub-ovate, apices acute ( Cartwright, 2001: fig. 11; Kimmins, 1962: fig. 5C; Neboiss, 1986a: fig. p. 108).

Female. Described by Kimmins, 1957 (fig. 5D; Cartwright, 2001: fig. 21; Neboiss, 1986a: fig. p. 108).

Remarks. Chimarra biramosa is known from many males (and females) from the Solomon Islands ( Johanson and Espeland, 2010; Kimmins, 1957) and PNG – Bougainville Island ( Cartwright, 2001), New Britain ( Oláh and Mey, 2013) and Western Highlands District. A new figure has been drawn to allow direct comparisons and to accompany the description that is revised in light of new interpretations of Chimarra genitalic structures from Kimmins’ (1957) original and Cartwright’s (2001) revised description. The one mainland PNG male specimen illustrated in this study, differs slightly from the type specimen. In Kimmins’ (1957) figure, the dorsal branch of the bifid inferior appendages, in lateral view, appears more robust than the ventral; in Cartwright’s (2001) figure, the dorsal and ventral branches appear nearly equally robust, but in the specimen studied here (fig. 86), the ventral branch appears more robust than the dorsal. These differences may be real or a matter of perspective in the different drawings.

Figures

Figures 86–93. Chimarra spp.; 86, Chimarra biramosa Kimmins, male, genitalia, lateral. 87–89, Chimarra kewabi sp. nov., male, holotype, genitalia; 87, lateral; 88, ventral, 89, dorsal. 90: Chimarra ulmeri Kimmins, male, genitalia, lateral. 91–93, Chimarra bicornis sp. nov., male, holotype, genitalia; 91, lateral; 92, ventral; 93, dorsal.