On seven undescribed leaf insect species revealed within the recent " Tree of Leaves " (Phasmatodea, Phylliidae)
Author
Cumming, Royce T.
https://orcid.org/0000-0001-7930-1292
Montreal Insectarium, 4581 rue Sherbrooke est, Montre ́ al, H 1 X 2 B 2, Que ́ bec, Canada & Richard Gilder Graduate School, American Museum of Natural History, New York, NY 10024, USA & Biology, Graduate Center, City University of New York, NY, USA
roycecumming@gmail.com
Author
Le Tirant, Ste ́ phane
https://orcid.org/0000-0001-7463-5621
Montreal Insectarium, 4581 rue Sherbrooke est, Montre ́ al, H 1 X 2 B 2, Que ́ bec, Canada
Author
Linde, Jackson B.
https://orcid.org/0000-0003-1480-0212
Department of Biology and M. L. Bean Museum, Brigham Young University, Provo, UT, USA
Author
Solan, Megan E.
https://orcid.org/0000-0002-2298-5336
Department of Environmental Science, Baylor University, Waco, TX, USA
Author
Foley, Evelyn Marie
https://orcid.org/0009-0007-9754-212X
Westville, New Jersey, USA
Author
Eulin, Norman Enrico C.
Saint Michael Academy-Catarman, Northern Samar, 6400 Philippines
Author
Lavado, Ramon
https://orcid.org/0000-0002-2774-5104
Department of Environmental Science, Baylor University, Waco, TX, USA
Author
Whiting, Michael F.
https://orcid.org/0000-0003-1157-888X
Department of Biology and M. L. Bean Museum, Brigham Young University, Provo, UT, USA
Author
Bradler, Sven
https://orcid.org/0000-0001-9307-1032
Department of Animal Evolution and Biodiversity, Johann- Friedrich-Blumenbach Institute of Zoology and Anthropology, University of Go ̈ ttingen, Untere Karspu ̈ le 2, 37073, Go ̈ ttingen, Germany
Author
Bank, Sarah
https://orcid.org/0000-0001-6952-1590
Department of Animal Evolution and Biodiversity, Johann- Friedrich-Blumenbach Institute of Zoology and Anthropology, University of Go ̈ ttingen, Untere Karspu ̈ le 2, 37073, Go ̈ ttingen, Germany
sarah.bank@uni-goettingen.de
text
ZooKeys
2023
2023-08-03
1173
145
229
http://dx.doi.org/10.3897/zookeys.1173.104413
journal article
http://dx.doi.org/10.3897/zookeys.1173.104413
1313-2970-1173-145
5704F5B5AE7B4A79A5DC0B6592A77837
84D07C53ABF15905807911007E9C0A27
Phyllium dardanus Westwood, 1859 (OUMNH; Fig. 20)
Phyllium gelonus
Gray, 1843 (NHMUK; lost according to
Brock et al. 2022
).
Differentiation.
Female
Pulchriphyllium crurifolium
stat. rev., comb. nov. are the easiest to differentiate from the other "
Pulchriphyllium bioculatum
"-like species by comparing the profemoral exterior lobe shape. In
Pulchriphyllium crurifolium
stat. rev., comb. nov. the anterior margin of the exterior profemoral lobe is nearly straight, giving the lobe a boxy appearance (Fig.
21A
) vs the other "
Pulchriphyllium bioculatum
"-like species which have this margin notably rounded, giving the lobe a slight recurve appearance (Fig.
21B
).
Figure 21.
Adult female profemoral lobes from various
Pulchriphyllium
species for comparison
A
Pulchriphyllium crurifolium
stat. rev., comb. nov. (NHMUK)
B
Pulchriphyllium bioculatum
from West Malaysia (Coll RC 16-038)
C
Pulchriphyllium scythe
stat. rev., comb. nov. from Sylhet, Bangladesh (OUMNH)
D
Pulchriphyllium pulcrifolum
from Java, Indonesia (Coll RC 16-024)
E
Pulchriphyllium bhaskarai
sp. nov. from Java, Indonesia (MZPW).
Males
are difficult to differentiate, and even after reviewing numerous specimens in series there appears to be enough intraspecific variation to make reliable differentiation impossible. On average males tend to have slightly narrower profemoral exterior lobes with a strongly obtuse angle (Fig.
22B
), but some of the other "
Pulchriphyllium bioculatum
"-like species can sometimes exhibit a similar lobe shape.
Figure 22.
Live
Pulchriphyllium crurifolium
stat. rev., comb. nov.
A
adult female, dorsal habitus, observed September 2019 at Sans Souci,
Mahe
, Seychelles, by Juan Jose Areso uploaded by iNaturalist user @liahg (Amalia Herrera Grau) (https://www.inaturalist.org/observations/76082181)
B
adult male, dorsal habitus, observed December 2006 at
Grand'
Anse,
Mahe
, Seychelles by iNaturalist user @thierrycordenos (https://www.inaturalist.org/observations/22992534). Both images uploaded to iNaturalist and used under license (CC BY-NC 4.0).
Eggs
of
Pulchriphyllium crurifolium
stat. rev., comb. nov. are slightly smaller than the other "
Pulchriphyllium bioculatum
"-like species and have a great deal more raised nodes throughout the surfaces (Fig.
23D-F
).
Figure 23.
Eggs from
Pulchriphyllium bioculatum
-like species, where the eggs are known
A-C
Pulchriphyllium bioculatum
from West Malaysia (Coll RC #18-042)
D-F
Pulchriphyllium crurifolium
stat. rev., comb. nov. from the Seychelles (Coll RC #18-233)
G-I
Pulchriphyllium agathyrsus
from Sri Lanka (Coll RC #18-232). Top row, dorsal view. Middle row, lateral view. Bottom row, anterior view.
To date, the authors have yet to see an observation of a freshly hatched nymph of this taxon. With how unique and species-specific congenerics are (Fig.
8
), it is likely that this species can be additionally differentiated by the freshly hatched nymph habitus.
Distribution.
(Fig.
15A
) At present known from three of the islands of the Seychelles:
Mahe
, Praslin, and La Digue (see Suppl. material 1 for list of observations).
Remarks.
This taxon was originally described as a unique species from the Seychelles (
Audinet-Serville 1838
); however, over the decades this taxon has been treated either as a synonym, subspecies, or local form of "
Pulchriphyllium bioculatum
" (
Giglio-Tos 1910
;
Brock 1995
;
Hennemann et al. 2009
). At present molecular data are lacking for this taxon, but there are numerous specimens in historic collections and recent citizen science observations (Fig.
22
) which illustrate a consistent and unique morphology. Biogeographically it is likely that this species is sister to the Indian or Sri Lankan species as other organisms are known to have utilized the Maldives archipelago from the Indian sub-continent at some point during low sea levels of the past to colonize the Seychelles (
O'Brien
2011
;
Bernardes et al. 2021
).
In the decades following the description of
Pulchriphyllium crurifolium
stat. rev., comb. nov., there were several other taxa described from the Seychelles, but since their description they have been synonymized with
Pulchriphyllium bioculatum
(
Brock et al. 2022
). Of the three taxa described from the Seychelles (
Phyllium crurifolium
,
Phyllium dardanus
, and
Phyllium gelonus
), only type specimens of
Phyllium crurifolium
and
Phyllium dardanus
remain (the type of
Phyllium gelonus
is reported as lost according to
Brock et al. 2022
). Thankfully, the syntype series of
Pulchriphyllium crurifolium
stat. rev., comb. nov. (the senior synonym) has survived within the OUMNH collection. Within the original description, the syntypes are noted as: "East Indies. The male labeled from the Seychelles Islands by Latreille. Collection of M. le comte Dejean. I have both sexes" (
Audinet-Serville 1838
). Of these specimens, the male from the Latrielle collection (Fig.
19D
), and three specimens labeled as from Serville (Fig.
19A-C
) have been traced within the OUMNH collection. Unfortunately, any syntypes which were within the "Collection of M. le comte Dejean" (Pierre
Francois
Marie Auguste Dejean; 1780-1845) could not be traced. In choosing the specimen to be designated as the lectotype, we chose the specimen in question following several lines of thought. First, we wish to designate a female specimen as males are morphologically indistinguishable from several congenerics. Second, following chapter 16, article 74E of the ICZN Code (
ICZN 1999
) we chose the female specimen with the explicit collection data of
"Seychelles"
(Fig.
19B
).
The eggs of
Pulchriphyllium crurifolium
stat. rev., comb. nov. are very similar to most
Pulchriphyllium
species therefore this species adds credibility to the phylogeny of
Buescher
et al. (2023)
. Within
Buescher
et al. (2023)
the
Pulchriphyllium
are primarily characterized as "type 7" eggs (defined as having "exochorionic structures fused to dense fins"). The only
Pulchriphyllium
species which lacks this type is
Pulchriphyllium giganteum
which is sister species to all other
Pulchriphyllium
. Even though
Pulchriphyllium crurifolium
stat. rev., comb. nov. could not be included within our phylogeny (Fig.
2
), based upon adult and egg morphology this species likely is more closely related to one of the other "
Pulchriphyllium bioculatum
-like" species.