Limnocassis compacta, Borowiec & Sekerka, 2015

Borowiec, Lech & Sekerka, Lukáš, 2015, On the genus Limnocassis Spaeth, with description of two new species from South Africa (Coleoptera: Chrysomelidae: Cassidinae), Zootaxa 3999 (2), pp. 272-278 : 276

Limnocassis compacta sp. nov.

(Figs 8–14)

Type material. Holotype: “ SOUTH AFRICA W Cape / Langebaan env. / Western Coast NP 70 m / 33°06'50.7"S, 18°07'49.9"E / 26.xii.2013 ” ( NMPC); four paratypes: the same data ( ADC , DBET , LSC , NMPC ). The type locality is situated in the Western Cape Province, in West Coast National Park, along the road R27.

Diagnosis. Limnocassis compacta sp. nov. is very similar to L. regularis sp. nov. in fine and mostly regular elytral punctation contrary to the strong and partly irregular punctation in L. pumilio . For differences see diagnosis of L. regularis .

Description. Length: 3.20–3.40 mm, width: 2.05–2.30 mm, length of pronotum: 1.15–1.25 mm, width of pronotum: 1.65–1.85 mm, length/width ratio: 1.48–1.60, pronotum width/length ratio: 1.42–1.50. Body stout, slightly cuneiform ( Figs 9, 11 ).

Body completely yellow, including head, legs and antennae, one paratype with two reddish spots at postscutellar elevation ( Figs 9–10 ).

Pronotum irregularly elliptical, with maximum width in 1/3 length, sides broadly rounded without basal corners, external margin of pronotum transparent. Disc convex, indistinctly bordered from the explanate margin, area above head placed slightly lower than top and lateral parts of disc. Surface of disc micro-reticulate and, except area above head, with sparse fine and shallow punctation, appears slightly alutaceous. Explanate margin of pronotum with transparent honeycomb structure, very shallowly punctate and its surface appears regular but slightly alutaceous.

Scutellum triangular. Base of elytra slightly wider than pronotum, humeri strongly protruding anterad but in lateral view humeral angles subangulate ( Fig. 10 ). Punctation of disc mostly forms more or less regular rows, two first rows slightly impressed, intervals 2, 4 and 6 in the middle with few additional irregular punctures but punctation of elytra at first glance appears regular. Punctures in row moderately coarse, moderately dense, distance between punctures from as wide as to twice wider than puncture diameter. Marginal row distinct, its punctures as coarse as punctures in central rows. Intervals flat, first three intervals approximately 1.5 times as wide as rows, interval 4 in punctate central part 2.5 times wider than in impunctate anterior and posterior part, interval 5 narrow but well marked as impunctate band, interval 6 broad, in punctate part thrice as wide as interval 5, interval 7 in anterior part as narrow as interval 5 in posterior third forms broad, impunctate but not elevated field, three marginal intervals approximately as wide as three sutural intervals. Interspaces smooth, slightly alutaceous. Explanate margin of elytra extremely declivous, almost perpendicular to the abdominal surface, narrow, in the widest part as wide as 1/4 width of disc. Surface with fine to moderate but shallow and dense punctation, slightly denser punctate than in L. regularis but slightly sparser than in L. pumilio , appears regular, punctures slightly finer than punctures in rows of disc, interspaces smooth, slightly alutaceous. Apex of elytral epipleura without erect setae.

Clypeus broad, slightly wider than long, flat, with fain clypeal grooves converging in triangle, along inner margin of eyes runs a row of setose punctures. Surface of clypeal plate flat, with 4–5 punctures, interspaces smooth and shiny. Eyes large but gena well marked, slightly longer than length of the last palpomere. Labrum moderately broad with broad median emargination, as deep as 1/5 length of labrum (Fig. 8). Prosternal collar well marked but short, as long as half length of the last palpomere. Prosternum between coxae moderately broad and moderately deep canaliculate, as wide as half width of coxa. Apical part of prosternal process wide, transverse, its surface regular with few small punctures (Fig. 8). Prosternal alae on sides elevated, ventral surface of pronotum close to sides of prosternal alae form a shallow gutter to accommodate antennae but the gutter is not as distinct as in genera of the tribe Cassidini with antennal grooves.

Antennae short, segments IX and X slightly wider than long, length ratio of antennomeres: 100:59:50:50:44:34:74:71:68:82:114. Segment II approximately 1.18 times as long as segment III, segment IV as long as III ( Fig. 12 ).

Tarsi narrow with distinct setose sole, last segment slightly shorter than third segment, claws simple ( Fig. 13 ).

Sexual dimorphism indistinct, genitalia not diagnostic.

Etymology. Named for having the stoutest body of all species of Limnocassis .

Distribution. South Africa: Western Cape Province ( Fig. 14 ).

Figures

FIGURE 14. Distribution of Limnocassis Spaeth in Hincks, 1952 in South Africa: Limnocassis compacta sp. nov. (blue circle), L. pumilio (Boheman, 1854) (green circles), and L. regularis sp. nov. (red circles).

FIGURES 9 – 13. Limnocassis compacta sp. nov.: (9) maculate form dorsal, (10) maculate form lateral, (11) immaculate form dorsal, (12) antenna, (13) tarsal claw.