The Mecyclothorax beetles (Coleoptera, Carabidae, Moriomorphini) of Haleakala-, Maui: Keystone of a hyperdiverse Hawaiian radiation
Author
Liebherr, James K.
text
ZooKeys
2015
544
1
407
http://dx.doi.org/10.3897/zookeys.544.6074
journal article
http://dx.doi.org/10.3897/zookeys.544.6074
1313-2970-544-1
C5978BD0145B40F8ACDEB27371B7B9A4
C5978BD0145B40F8ACDEB27371B7B9A4
Taxon classification Animalia Coleoptera Carabidae
(047)
Mecyclothorax ovipennis Sharp
Figs 61
C-E
, 62B, 63B, 65A, 66
Mecyclothorax
ovipennis
Sharp 1903
: 250;
Britton 1948b
: 145;
Swezey 1954
: 27, 53 (biology);
Liebherr 2005b
: 109.
Diagnosis.
Among
Haleakala
Mecyclothorax
(Fig. 65A), this is most similar to the preceding,
Mecyclothorax strigosus
(Fig. 60D) based on the well-developed eyes, ocular ratio = 1.55-1.61 and ocular lobe ratio = 0.84-0.89, plus basally constricted pronotum and ellipsoid elytra. They can be separated by the setal conformation, with this species characterized by a quadrisetose pronotum, and presence of the apical elytral seta; setal formula 2 2 2 1[ae]. This species is characterized by the same setal formula as
Mecyclothorax flaviventris
, but individuals of that species exhibit punctate discal striae (Fig. 68C). Standardized body length 3.7-4.9 mm.
Figure 65.
Mecyclothorax ovipennis
group species, dorsal habitus view. A
Mecyclothorax ovipennis
(Kīpahulu, 1800 m) B
Mecyclothorax takumiae
(Paliku, 1950 m) C
Mecyclothorax apicalis
(summit, 2895-3050 m) D
Mecyclothorax parapicalis
(Holua, 2135 m).
Identification
(n = 5). The pronotum is very cordate in this species, MPW/BPW = 1.46-1.59, with the lateral margin subparallel to convergent for 0.2
x
the pronotal length anterad the projected, right to acute hind angles. The pronotum appears elongate, but is actually slightly transverse; MPW/PL = 1.08-1.21. The surface of the pronotal disc, and anterior transverse impression and associated callosity are irregularly wrinkled. Of the elytral striae, only sutural stria 1 is moderately deep basally, with elongate punctures that expand the stria basally, the stria smooth and deep apically. Striae 2-4 are shallower on the disc, striae 5-7 progressively shallower, and striae 6-7 discontinuous. At the elytral apex, stria 2 is of subequal depth to the sutural stria, fused striae 3 + 4 and 7 are present, and the apices of striae 5 and 6 are shallow but traceable. The vertex bears isodiametric and transverse sculpticells in transverse rows, the transverse sculpticells 2
-3x
broad as long. The pronotal and elytral discs are covered with transverse-mesh microsculpture, sculpticell breadth 1.5
-3x
length; the pronotal base has a shallow transverse mesh between glossy portions of the cuticle.
Male genitalia (n = 8). Aedeagal median lobe gracile, distance between parameral articulation and tip 4
x
depth at midlength (Fig. 61C); apex well extended beyond apex of ostial opening, dorsal surface of projection broadly convex, then flattened dorsad
tightly
rounded tip, ventral margin slightly concave due to downward curvature of tip (Figs 61
C-D
); median lobe not curved in ventral view, though left margin distinctly incurved to apical extension, and right margin concave before apex (Fig. 61E); internal sac broader near flagellar plate, covered with well-developed pelage of microspicules, the spicules densest on ventral surface forming a poorly developed ventral ostial microtrichial patch (Fig. 61D); flagellar plate moderately elongate, length 0.42
x
parameral articulation-tip distance.
Female reproductive tract (n = 1). Bursa copulatrix columnar, subdivided into broader basal portion and slightly narrower apical lobe, overall length 0.91 mm, breadth 0.31 mm (Fig. 62B); bursal walls diaphanous, very thin and with indistinct wrinkles; gonocoxite 1 with 4-5 apical fringe setae, a curved seta just basad apicomedial angle, and 8-10 smaller setae on medial margin, setae subequally divided between ventral and dorsal surfaces (Fig. 63B); gonocoxite 2 falcate with tightly rounded apex, base extended laterally into sinuous panhandle, 2 subequal lateral ensiform setae, apical nematiform setae on medial surface at 0.68
x
gonocoxite length.
Lectotype.
Female (BMNH) designated by
Liebherr (2005b
: 110). Type locality Haleakala, 4500-6000 ft., III-1894 (R.C.L.P. lot 383;
Anonymous N D
).
Distribution and habitat.
Mecyclothorax ovipennis
is among the most broadly distributed
Mecyclothorax
species on
Haleakala
(Fig. 66). It requires, at the minimum, mesic forest conditions, being isolated at Polipoli Springs on the Kula face. It occurs along the eastern margin of
Haleakala
Crater where mesic forest occurs. It is also at home in wetter forest situations throughout Waikamoi,
Hanawī
,
Hana
Bogs,
Kīpahulu
Valley, and the Manawainui Planeze. It has been collected in habitats ranging 880-2134 m elevation. It has been found in association with a great diversity of plant species, including ferns (
Asplenium
,
Cibotium
,
Dicranopteris
, and
Sadleria
), herbaceous secondarily woody shrubs (
Coprosma
,
Cyanea
,
Myrsine
,
Rubus
, and
Vaccinium
) and emergent trees (
koa
and
'ōhi'a
). It is also commonly encountered in sifted litter.
Figure 66. Recorded geographic distribution of
Mecyclothorax ovipennis
.