Balta Tepper, 1893

Rentz, David Cf & Su, You Ning, 2025, New cockroaches from Far North Queensland, Australia (Blattodea: Ectobiidae: Blattellinae; Pseudophyllodromiinae), Zootaxa 5696 (1), pp. 41-62 : 57-60

Balta Tepper, 1893

Type species: Balta epilamproides Tepper 1893: 40 .

Allactina Hebard, 1929: 18 ,

Type species: Allactina jacobsoni Hebard.

Eoblatta Shelford, 1911 ,

Type species: Blatta notulata Stål by original designation.

Graptoblatta Hebard 1929 .

Type species: Blatta notulata Stål by original designation.(unnecesssary replacement, see Beccaloni 2024).

Hebardula Uvarov, 1939 .

Type species: Allactina jacobsoni Hebard. Name not used. (see Beccaloni, 2024)

Mareta Bolívar 1895 ,

Type species: Mareta conspicienda Bolívar (= Balta innotabilis ). (name not published and represents a misidentification, see Beccaloni, 2024).

Balta is a large genus with 86 described, nocturnal species, at least 40 of which are found in Australia (see Roth, 1991: 967 and Hebard 1943: 37). Recent collecting indicates double that number for Australia. The non-Australian Balta species occur in the Pacific Islands, Asia and Africa (see Princis, 1969).

Balta cockroaches have a distinctive appearance (see Rentz, 2014: 257-272). Often more than one species can be found at a given locality. All are known to be nocturnal. Groups of species have an overall similar appearance. Whether these can be considered as distinctive genera remains for future extensive revisions. For the present, we can see at least one distinctive group of Australian species. We propose a “species group”, the Godeffroyi Group based on the oldest species in the group, B. godeffroyi (Shelford, 1911) . We include in that group two other Australian species B. fratercula Hebard and one we herein describe.

Generic diagnosis. Head seemingly without ocelli, however, the light patches at the base of the antennae may be lateral ocelli and the vague darkening of the central portion of the frons may be the vestiges of a median ocellus; interocular space wider than inter-antennal space; both sexes fully winged, although some females may not be capable of flight. Ventro-anterior margins of fore femur with an elongate row of piliform spines; median and caudal femora armed with spines. Males with dorsal surface of abdomen unspecialised; supra-anal plate broadly convex and not specialised; subgenital plate deeply cleft, often at an angle, lateral portions asymmetrical, apex bearing 4 distinctive styles, lateral margins often twisted or otherwise modified. Female subgenital plate simple.

Balta Godeffroyi Group Rentz, & Su , new species group

Flickr: https://www.flickr.com/photos/naturenoises/albums/72157639340999195/page5

Distinctive characters. Pronotum with distinctive, intensive angulate markings; dorsum of head with prominent stripes; tegmina dark but the veins whitish; male subgenital plate deeply incised at an angle and with 4 appendages; male concealed genitalia exceedingly complex; female subgenital plate deltoid, apically acute. Species of the Godoffroyi Group and other Balta can be seen at the Flickr site noted above.

Key to known species of the Godeffroyi Group

1. Each tegmen with an elongate creamish white stripe in the middle ( Figs 9A , 11B ). Frons with a faint darkish patch at base of antennal socket ( Fig. 9B ). Antenna with scape and pedicel straw brown, succeeding several segments black, remainder of flagellum light straw brown ( Figs 9A , 11B ). Male subgenital plate with U-shaped median portion, each side with a pair of rather similar digits ( Fig. 9C ). Distribution, Map 1 . Balta rothi Rentz and Su , sp. nov.

1’ Without above combination of characters.................................................................. 2

2. Head with frons bearing a broad black dorso-ventral stripe almost covering entire surface ( Fig. 7B ). Central portion of pronotum plain, lacking a thin spear-like stripe in the middle ( Fig. 7A ). Male subgenital plate with an angulate median incision, each side bearing 2 styles, the outermost style on the left bearing several short, stout teeth ( Fig. 7C ). Balta godeffroyi (Shelford) Distribution. Central Australia and coast Queensland, Northern Territory and Western Australia, see Rentz (2014: 263).

2’. Head with frons bearing a narrow, light brown dorso-ventral stripe ( Fig. 8B ). Central portion of pronotum bearing a thin spear-like stripe ( Fig. 8A ). Male subgenital plate with styles on the left large and heavy and with a single style on the right ( Fig. 8D ) See Hebard 1943, pl x, Fig. 12, note this figure is “external view”). Habitus Figs 8A (male); B, (female). Balta fraterula Hebard Distribution coastal Queensland continuously across the Gulf to and including the Northern Territory. see Rentz (2014: 262).

Figures

MAP 1 Known distribution of three species. S Carbrunneria cattana sp. nov. z Cattaniaria tripartita sp. nov. T Parectoneura queenslandica sp. nov.

FIG. 9. Balta rothi Rentz & Su sp. nov. A. Adult male. B. Adult male, ventral view. C. Male subgenital plate, outer view. D. Male genitalia, extruded. E. Male genitalia obverse view. F. Female tenth tergite. G. Female subgenital plate.

FIG. 11. Comparison of two blattellines with similar colouration.A. Allacta australiensis Roth is commonly found on tree trunks at night. B. Balta rothi Rentz & Su sp. nov. has been found only once on tree trunks but the colour pattern suggests such a lifestyle.

FIG. 7. Balta godeffroyi (Shelford). A. Adult male. B. Adult male, ventral view. C. Male subgenital plate. D. Adult male. Note head.

FIG. 8. Balta fratercula Hebard. A. Adult male. B. Adult female. C. Male, ventral view. D. Male subgenital plate. Modified from Hebard (1943, Fig. 12), external view.