Yamuy Arriaga-Varela, Tomaszewska, Szawaryn, Robertson, Seidel, Ślipiński & Fikáček, 2023, GEN. NOV.
Creators: name: Arriaga-Varela, Emmanuel
name: Tomaszewska, Wioletta
name: Szawaryn, Karol
name: Robertson, James
name: Seidel, Matthias
name: Ślipiński, Adam
name: Fikáček, Martin
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Mycetaeidae
Yamuy

description: YAMUY ARRIAGA- VARELA, TOMASZEWSKA &
SZAWARYNGEN. NOV.
(FIGS 12–16)
Zoobank registration: urn: lsid: zoobank. org:act: ACB24628-6F19-494F-8866-3CFA28015395
Type species: Yamuy marginatus b y p r e s e n t designation.
Diagnosis: Yamuy can be distinguished from other genera of Cerasommatidiidae by the following combination of characters: dorsal surface of the body covered with two kinds of vestiture (Figs 12, 15F, 16A, B): minuscule decumbent setae and sparse long erect setae/ spines; lateral margins of the pronotum with complete (Fig.16B) or reduced/short and present only basally (Fig. 15C) internal subparallel carina demarcating a wide area; anterior margin bordered narrowly with simple bordering line; prosternal process strongly narrowed preapically with lateral carinae short, anteriorly not extending beyond prosternal process (Figs 15D, 16C); trochanters simple, not covering the tibio-tarsal joint when retracted (Figs 15D, 16D); abdominal ventrite 1 without postcoxal lines (Figs 15H, 16F); aedeagus with tegmen sclerotized, fused to base of penis (Fig. 14B, E). The mixed vestiture (vestiture homogeneous in Cerasommatidia, Karumbe and MahaƲelo) and the simple not flattened trochanters are unique within the family (in Cerasommatidia, Karumbe and MahaƲelo trochanters are flattened and expanded posteriorly to cover the tibio-tarsal joint in repose).
Description: Length 0.90–0.95 mm. Body short oval and convex, 1.6 times as long as wide, around 2.0–2.2 times as long as high. Coloration light brown to yellow, sometimes with contrasting markings on elytra, and whitish legs (Fig. 12A–D).
Head with dorsal surface with two kinds of vestiture: sparse tiny decumbent hairs and a pair of long erect setae in vertex near posterior margin of each eye (Fig. 16A). Clypeus large, rectangular (Fig. 15B). Frontoclypeal suture distinct, straight. Ventral antennal grooves short, not extending to posterior eye level (Fig. 15A). Antenna approximately 0.4 of length of body (Figs 13A, 15A); antennal club one quarter of total antennal length; antennomeres 1–5 longer than wide, with antennomere 5 longer than neighbouring antennomeres 4 and 6; antennomeres 6–9 variable in species. Eyes comparatively large, moderately prominent (Figs 15B, 16A). Galea large, densely setose at apex (Fig. 13C). Lacinia weakly narrower than galea with dense setae at apex and inner margin. Labium with mentum widest near midlength (Fig. 15A); with palpomere 2 and 3 large, bulbous, transverse and subtriangular respectively; terminal palpomere short and rounded to elongate acuminate, around 2 times as long as wide at base.
Prothorax. Pronotum 1.8–2.0 times wider than long, widest between base and basal third, weakly to moderately strongly convergent anteriorly, 1.3– 1.6 times wider at widest part than on front angles. Anterior margin narrowly bordered with regular bordering line; base of pronotum weakly sinuate with margin narrowly bordered with faint bordering line or unbordered (Figs 15C, 16B). Pronotal sides scarcely rounded, with complete (Fig. 16B) or short/reduced internal lateral carina present only at base (Fig. 15C), with area between carina and the lateral edge weakly concave, wider near basal third; hind angles with or without small, oblique indentation to receive humeral corner of elytron. Pronotal disc moderately to weakly convex, with surface covered with two kinds of vestiture: sparse small punctures bearing tiny decumbent hairs, and a pair of long erect setae. Prosternum with anterior margin scarcely arcuate posteriorly (Figs 15D, 16C); prosternal process narrow, at apex about 0.25–0.30 of width of procoxal cavity, with raised lateral carinae reaching anteriorly before or briefly beyond level of anterior margin of procoxal cavities; area between carinae concave; prosternal process extending posteriorly to hind level of procoxae. Hypomeron with deep and comparatively long, sinuate antennal grooves (Figs 15D, 16C).
Pterothorax. Mesonotum with scutellar shield small, transverse, weakly rounded at apex (Fig. 16B). Mesoventrite with intercoxal process smooth, almost flat with anterior raised border incomplete medially; 1.0–1.4 times as wide as mesocoxal diameter (Figs 13D, 15G, 16D). Metaventrite as long as abdominal ventrites 1–3 together; with complete discrimen (visible only in the internal part of the ventrite after dissection, Fig. 13D); anterior margin with bordering line slightly widened towards lateral corners, with or without small longitudinal carina below each coxa; central area with fine setiferous punctures (Figs 15G, 16D). Anterior part of metanepisternum with small outer angulate projection. Elytra about 0.6 mm long, about as long a wide, 2.5 times as long and 1.3 times as wide as pronotum, with lateral margins narrowly explanate (Figs 12A, C, 15F). Surface with two kinds of vestiture: sparse small punctures bearing tiny decumbent hairs, and long setae: sparse in the centre of elytral disc (about eight to 14 setae) and arranged in a row near lateral margins (around eight to ten setae). Epipleura comparatively narrow, narrowing toward apex reaching nearly elytral apex but incomplete, with internal bordering line narrow, present from the level of mid-coxae to apex. Hindwings well developed, without anal lobe, with single reduced anal vein, and median fleck present, undivided.
Legs. Trochanters not modified (Figs 15G, 16D). Femora weakly flattened (mid and hind femora more distinctly than fore femora); with grooves for tibiae present throughout whole length. Claws with comparatively large, sharp subquadrate tooth at base (Figs 13F, 15E, 16E).
Abdomen with ventrite 1 with anterior marginal bordering, without postcoxal lines, with or without small longitudinal carina below each coxae (Figs 15H, 16F).
Male genitalia (Fig. 14B, E). Aedeagus with penis short and stout, sclerotized, weakly curved, asymmetric, with ramificate apex. Tegmen sclerotized, short, ring-like, fused to penis at base, with long ramus extending anteriorly; tegminal strut short, reduced.
Female genitalia (Fig. 14C, F). Spermatheca large, elongate, irregular ‘infundibuliform’, submembranous; sperm duct short; accessory gland small membranous, of irregular shape.
Etymology: Yamuy is the Taíno word for ‘cat’, referring to the whisker-like setae on the pronotum and elytra, characteristic of this genus. Gender masculine.
Species included: Yamuy constratus, Y. marginatus.
Distribution: Puerto Rico, Venezuela (Fig. 20A).
description: Published as part of Arriaga-Varela, Emmanuel, Tomaszewska, Wioletta, Szawaryn, Karol, Robertson, James, Seidel, Matthias, Ślipiński, Adam & Fikáček, Martin, 2023, The resurrection of Cerasommatidiidae, an enigmatic group of coccinelloid beetles (Coleoptera: Coccinelloidea) based on molecular and morphological evidence, pp. 1078-1115 in Zoological Journal of the Linnean Society 197 (4) on pages 1101-1103, DOI: 10.1093/zoolinnean/zlac082, http://zenodo.org/record/7814127