New Species and Records of Costa Rican Featherwing Beetles (Coleoptera: Ptiliidae)
Author
Darby, Michael
text
Zootaxa
2016
4184
1
41
51
journal article
10.11646/zootaxa.4184.1.2
6a80d4c8-9142-43f3-8e2f-ad72423fb244
1175-5326
164467
396B3FCE-089E-4661-A6D0-FE464D4AAA71
Seminis
gen. n.
(
Figs. 7 A–K
)
From the Latin noun
semen
meaning a plant seed, gender neuter. Type species
Seminis factiosum
sp. n
.
Description.
Small, rounded, pubescent species easily mistaken for a plant seed. Colour dark brown. Antennomeres 11 segmented, antennomeres 1 and 2 larger than 3–8; 4–8 elongate (5 & 7 longer than remainder), 9–11 forming a loosely jointed club,
Fig. 7B
. Eyes present. Mentum +/– square. Pronotum without obvious reticulation, slightly wider than elytra, hind angles smoothly rounded in lateral view. Scutellum triangular without any distinctive features. Elytra widest at apex of scutellum, with a short narrow epimeron at the humerus,
Fig.
7I
. Proventrum narrow, coxae almost contiguous and almost reaching anterior margin, coxal cavities open behind. Mesoventrum, clearly reticulate, collar strongly curved posteriorly at humeri, lateral margins very narrow, hind margins directed anteriorly from procoxal margin, keel reaching beneath mesocoxae in life, ventral surface narrowly eliptical, pubescent, flattened,
Figs.7E, F
. Metascutellum with two marginal spines
Fig. 7K
. Metaventrum clearly reticulate, posterior with two sharp points at corners,
Fig.
7F
. Abdomen: reticulation of ventrites distinct, cells bearing a single posteriorly directed seta alternating with others fringed with microtrichiae,
Fig. 7H
; tergites II–V with wing folding spicule patches, palisade fringe on tergite VII absent; pygidium composed of tergites IX–X fused, with small apical and two lateral points on posterior margin, anterior margin with row of setae.
Fig. 7J
; glands as described by
Hall (2003)
absent. Wings of usual ptiliid
type
.
Separation from related species
. The distinctive spatulate form of the mesoventral keel is similar to that of
Nossidium katyae
, species of the genus
Kuschelidium
Johnson
and, in a reduced form, to those of
Limulopteryx
Hall. Of
these
Seminis
is only likely to be confused, if the ventral characters are examined, with
Kuschelidium
. From that genus it may be separated by the absence of antennal grooves on the proventrum, the shorter elytra, the absence of short carinae running posteriad from the mesocoxal cavities, and the widely separated metacoxae. A similar spatulate mesoventral keel is also present in members of the subfamily
Cephaloplectinae
but in that case it is a feature of the proventrum and not of the mesoventrum.
Kuschelidium
was placed by Johnson in the
Ptinellini
, and by
Sawada and Hirowatari (2002)
close to
Mikado
(in the
Nanosellini
) although their decision was based on Japanese specimens which differ markedly from
K.maori
Johnson
, the type species of the genus. On ventral characters in particular
Seminis
looks closest to
Acrotrichis
and its place in the subfamily
Acrotrichinae
appears to be confirmed by the presence of the lateral spines on the metascutellum noted by Hall to be absent in all other ptiliid subgroups (
Hall 2003
,
2005
). The symmetrical form of the aedeagus, the incised sternite VI, the form of sternite VII with a short apodeme and the fused tergites IX and X forming the pygidium support that, but it should also be noted that the palisade fringe on tergite VII present in
Acrotrichis
is absent in
Seminis
.
Species of
Limulopteryx
and the
Cephaloplectinae
are known to be termitophilous, and the possibility exists that species of
Seminis
(and
Nossidium katyae
) may also be associated with termites or ants.