Lithosiccia, a new genus with four new species from mainland Africa (Lepidoptera: Erebidae: Arctiinae: Lithosiini)
Author
Volynkin, Anton V.
0000-0001-9447-4925
The African Natural History Research Trust (ANHRT), Street Court Leominster, Kingsland, HR 6 9 QA, UK. E-mail: anton @ anhrt. org. uk; https: // orcid. org / 0000 - 0001 - 9447 - 4925 & Altai State University, Lenina Avenue 61, RF- 656049, Barnaul, Russia.
text
Ecologica Montenegrina
2023
2023-08-23
65
24
39
http://dx.doi.org/10.37828/em.2023.65.4
journal article
10.37828/em.2023.65.4
2336-9744
13246318
urn:lsid:zoobank.org:pub:12E2157F-D422-492F-8446-768018FD52DA
Lithosiccia
gen. n.
https://zoobank.org/
urn:lsid:zoobank.org:act:
12B9A5B3-152F-4870-AEA4-E924A0CC5ED0
Type
species:
Lithosiccia smithi
sp. n.
Diagnosis.
The new genus is hereby assigned to the tribe
Cisthenina
and its species (
Figs 2–15
) are externally reminiscent of
Palaeosiccia
(
type
species:
Palaeosiccia punctata
Hampson, 1900
) (
Figs 16, 17
) due to their relatively broad forewing and the bipectinate male antenna but are distinguished by the brown or ochreous forewing ground colour (it is off-white or pale greyish in
Palaeosiccia
), and the dark, greyish-brown or grey hindwing ground colour in males, which is markedly paler, off-white or slightly suffused with grey in the similar genus. Compared to another
Cisthenina
genus occurring in the Afrotropics,
Siccia
(
type
species:
Siccia caffra
Walker, 1854
) (
Figs 18, 19
), species of
Lithosiccia
have a relatively broader and darker coloured forewing, but the reliable generic identification requires the examination of the copulatory organs. The male genital capsule of
Lithosiccia
(
Figs 20–29
) is distinguished from both
Palaeosiccia
(
Fig. 30
) and
Siccia
(
Fig. 31
, see also Volynkin (2023)) by the structure of the valva, which is clearly subdivided into the broad and long sacculus with an elongate and narrow distal process, and the costa extended distally into a narrow sclerotised process (called the ‘cucullus’ herein). Additionally, the tegumen of
Lithosiccia
has broad but weakly sclerotised lobes anteriorly, which protrude into the intersegmental membrane connecting the genitalia with the abdomen cuticle, the feature characteristic of the genus. Another feature characteristic of the genus is the ductus ejaculatorius opening on the ventral side of the phallus whereas in
Palaeosiccia
,
Siccia
and other related genera, it opens dorsally. The female genitalia of the new genus (
Figs 32, 33
) are distinguished from
Palaeosiccia
(
Fig. 34
) by the lack of the antevaginal plate and the lateral subostial plates, the corpus bursae bearing broad and dense clusters of robust spines, and the well-developed appendix bursae situated laterally or postero-laterally whereas it is reduced and situated postero-ventrally in the aforementioned genus. Compared to
Siccia
(
Fig. 35
, see also Volynkin (2023)), the female genitalia of
Lithosiccia
lack the lateral subostial lobes. Additionally, the 8
th
and the 7
th
abdominal sternites of
Lithosiccia
bear lateral gelatinous pockets which are not found in
Palaeosiccia
or
Siccia
.
Description
.
External morphology of adults
. Male antenna shortly bipectinate, female antenna setose-serrulate. Body brown. Forewing ground colour from pale ochreous brown to deep brown. Forewing markings dark brown or blackish. Transverse lines irregularly zigzagged or sinuous, indistinct in certain species. Proximal cellular spot small, dot-shaped. Discal spot large and various in shape. Hindwing brown or greyish-brown, discal spot diffuse.
Male genitalia
. Uncus elongate and slender, medially dilated and distally tapered, with tiny claw-shaped tip. Tuba analis weakly setose. Arms of tegumen fused in dorsal third and anteriorly tapered, with broad but weakly sclerotised lobes anteriorly protruding into the intersegmental membrane. Vinculum shorter than tegumen, more or less U-shaped. Valva clearly subdivied into dorsal and ventral (saccular) parts. Dorsal part of valva distally narrow and well-sclerotised, downcurved in certain species. Sacculus broad, with setose or spinulose dorsal margin. Distal saccular process elongate and narrow, almost straight. Juxta weakly sclerotised, trapezoidal, in certain species with two short and serrulate apical processes. Phallus large, cylindrical, almost straight or slightly upcurved distally. Ductus ejaculatorius originates anterio-ventrally. Vesica broad, sack-like, with short diverticula of various shapes, and large horn- or plate-like distal cornutus; in certain species with additional proximal plate-like cornutus or cluster of spines.
Female genitalia
. Papilla analis broad, trapezoidal, weakly setose. Apophyses long and thin. Postvaginal area with scobinated cluster. Ostium bursae broad. Ductus bursae short and broad, weakly sclerotised, with short gelatinous antrum in certain species. Corpus bursae with sclerotised posterior and membranous anterior sections, former bearing clusters of numerous robust spines protruding into anterior section laterally in certain species. Appendix bursae short, situated postero-ventrally or laterally, basally spinulose in certain species. 7
th
(and 6
th
in certain species) abdominal sternite(s) with lateral gelatinous pockets.
Molecular data
.
The pairwise distances between morphospecies are in the range of 4.11–8.77%. At the current stage it is impossible to evaluate the intrapopulational divergences due to the limited number of specimens sampled, the only example available being
two specimens
of
L. juvenis
from
Guinea
which have identical COI sequences.
The
intraspecific divergences between different populations of the same species vary significantly with pairwise distances in the range of 0.46–3.95% (
Fig. 1
)
.
Distribution
. Species of the genus are distributed in rainforests of West and Central Africa.
Etymology
. The genus name is an aggregate of the genus-group names
Lithosia
Fabricius, 1798
and
Siccia
and refers to the close relationship with
Siccia
and the valva clearly subdivided into the dorsal and ventral parts like in many genera of the subtribe
Lithosiina
.