Apodrosus mammuthus Girón & Franz, 2010

Girón, Jennifer C. & Franz, Nico M., 2010, Revision, phylogeny and historical biogeography of the genus Apodrosus Marshall, 1922 (Coleoptera: Curculionidae: Entiminae), Insect Systematics & Evolution 41, pp. 339-414 : 379-381

Apodrosus mammuthus Girón & Franz sp.n.

( Fig. 12 )

Diagnosis

Apodrosus mammuthus is characterized by the combination of its large size (at 6 mm it is the largest species in the genus), a long and escudate body form which is 2.8-times longer than its greatest width in dorsal view, which is at the anterior third of the elytra, a visible nasal plate, only slightly projected eyes, and a vestiture composed of white iridescent (reddish) scales and with curved, decumbent white setae. This species may be differentiated from the otherwise very similar A. argentatus by its more elongate head, and the aedeagus with a pair of denticulate pads on the endophallus positioned apicad of midpoint, and a thickened apical margin.

Specimens examined

Holotype ♀ “ PUERTO RICO, Mona Island, Bajura Los Cerezos , 45 m, N 18°5′18″, W 67°54′4″, May 22 2008, Leg. N. Franz ” ( UPRM) ; paratypes, same label information as holotype (CWOB: 1 ♂, 1 ♀; MEBT: 1 ♂, 1 ♀; UPRM: 3 ♂, 1 dissected ♀); “TURKS & CAICOS ISLS., Grand Turk; North Wells, 21°29′50″N, 71°08′20″W, 7 February 2001/ At black light in mixed scrub near salt pond; Coll. W. E. Steiner & J. M. Swearingen” (NMNH: 1 dissected ♂); “Mona Id., P. R., Coll: Martorell/ April 1/ 40 Acc# 283-40/ on Colubrina colubrina ” (UPRM: 1 ♂); “PUERTO RICO, Mona Island, near Playa Pájaros, 35 m, at night, N 18°3′52″, W 67°52′12″, May 18-2008, Leg. N. Franz” (UPRM: 2 ♂, including 1 dissected, 1 dissected ♀); “PUERTO RICO, Mona Island, Playa Sardinera, 0 m, N 18°5′19″, W 67°56′17″, May 20-24 2008, Leg. N. Franz” (UPRM: 4 ♂, 1 ♀); “PUERTO RICO, Mona Island, Sendero Capitán, 40 m, at night, incl. Hg/UV lights, N 18°5′16″, W 67°56′16″, May 20 2008, Leg. N. Franz” (UPRM: 6 ♂, including 1 dissected, 3 ♀, including 1 dissected).

Description

Body length 6 mm; in dorsal view ( Fig. 12A ) 2.8-times longer than greatest width which is at basal third of elytra, shape escudate; dorsal outline in lateral view ( Fig. 12C ) slightly convex. Integument surface smooth; vestiture composed of white iridescent (reddish) scales, with curved, decumbent setae. Eyes ( Fig. 12B ) 1.7-times longer than wide, slightly projected; 0.5-times width and 0.6-times length of head in lateral view, separated from anterior margin of prothorax by 0.5-times greatest diameter of eye; line of anterior margin of eyes flat; shortest distance between eyes (in dorsal view) 0.2-times greatest width of pronotum; median furrow ( Fig. 12B ) linear, deep, extending from anterior margin of eyes to their posterior margin. Rostrum ( Fig. 12B ) 1.1-times longer than wide; epistome apically with 2–4 setae situated on each side, extending posteriorly as a longitudinal narrow keel nearly to base of rostrum; nasal plate visible (though poorly defined), flat. Length of rostrum in lateral view 1.3-times its basal width; antennal insertion apicad of midpoint of rostrum; scrobe curved downwards by 45°, directed posteriorly at end, extending to midpoint of eye, separated from it by width of scrobe. Mandibles with 2 lateral setae. Antennae light brown; antennal scape extending to posterior margin of eye; funicular antennomere I 1.1-times longer than II; antennal club 0.5-times length of funicle, 2.5-times longer than wide. Pronotum ( Fig. 12A ) subquadrate, slightly wider than long, greatest width at midpoint; dorsal surface shallowly puncturate, each puncture with a curved, white seta; posterior margin bisinuate, 1.4-times wider than anterior margin; prothorax in lateral view with dorsal outline slightly convex, 1.5-times length of ventral outline; scutellum suboval, covered with scales. Mesosternum ( Fig. 12D ) 0.6-times length of prosternum. Metasternum with lateral portions posteriorly produced (in lateral profile gradually ascending towards posterior fourth, thereafter descending roundly, posterior face covered with scales); distance between posterior margin of mesocoxae and anterior margin of metacoxae 0.7-times length of prosternum. Legs with profemora 1.1-times length of pronotum; claws divergent. Elytra in dorsal view ( Fig. 12A ) 1.7-times their greatest width which is 1.6-times wider than pronotum; anterior margins sinuate; humeral region 1.5-times width of posterior margin of pronotum; apex rounded; in lateral view ( Fig. 12C ) with dorsal outline convex; posterior declivity gradually rounded (not angulate); striae IX and X completely separated along their entire length; intervals covered with white, gray and light brown scales forming a spot pattern on anterior and apicad of midpoint areas of elytra; interval X produced apicad of basal sixth; with curved, decumbent setae. Venter ( Fig. 12D ) with gray scales denser on sides and scattered setae; ♂: IV 1.6-times longer than V and VI jointly, slightly longer than VII, VII with anterior margin 1.9-times wider than its length, posterior margin widely rounded; ♀: IV 1.8-times longer than V and VI jointly, 1.6-times length of VII, VII with anterior margin 2.2-times wider than its length, posterior margin rounded.

Terminalia. Male with tergum VII 1.5-times wider than its mesal length, mesal area 1.4-times wider than a strigulate stripe, with scarce setae; anterior margin with mesal area roundly projected, posterior margin emarginate. Tergum VIII 1.4-times wider than its mesal length; anterior margin slightly emarginate with a mesal deep and narrow emargination; surface with an anteapical, concave, rounded fold; posterior margin widely rounded. Sternum VIII with spiculum relictum forming a forked process with base 1.5-times longer than wide and as long as each arm, arms darker for the most part. Spiculum gastrale with apodeme 1.1-times longer than aedeagus, each furcal arm sclerotized, sub-oval, with parallel inner margins. Tegmen with tegminal apodeme 0.6- times length of aedeagus; tegminal plate posteriorly widely and roundly slightly projected. Aedeagus in dorsal view ( Fig. 12E ) 3.5-times longer than its greatest width, slightly narrowed basad of midpoint, apically slightly widened; apex roundly triangular, with narrow round lateral corners, mesally thickened; mesal region of apex with longitudinal stripes. Endophallus with a pair of lateral, equilateral, opposed plates positioned near apex, a pair of denticulate pads positioned apicad of midpoint, and an elongate, rhomboidal, median sclerite, positioned at midpoint of aedeagus; with a pair of dark opposed, sickle-shaped sclerites positioned basad of midpoint, between these with a pair of smaller sclerites and with 2 lateral rows of 5-6 stepwise alternating triangular teeth. Aedeagus in lateral view ( Fig. 12F ) 9.2-times longer than its greatest width. Aedeagal apodemes 0.8-times length of aedeagus.

Female. With tergum VII as wide as its mesal length, posterior margin rounded. Tergum VIII nearly trapezoidal, 1.6-times wider than long. Sternum VIII with semioval lamina, occupying posterior one fifth. Coxites+styli slightly shorter than lamina of sternum VIII, stylus 3.2-times longer than its greatest width, with 3-4 apical, long setae. Genital chamber 0.6-times length of sternum VIII. Spermatheca ( Fig. 12G ) 1.5- times longer than wide, Y-shaped; cornu slightly shorter than greatest width of spermatheca; ramus apically truncate; collum apically narrowed; surface not particularly sculptured.

Variation

Th e examined specimens vary little beyond slight differences in scale coverage, with some abraded specimens appearing darker. There are only minimal inter-population differences in aedeagal structure.

Etymology

Named after giant mammoths (genus Mammuthus) since it is the largest species presently assigned to the genus. The species epithet is to be treated as a noun in apposition.

Natural history

Apodrosus mammuthus occurs in coastal shrubby habitats (0–55 m) on Grand Turk of the Turks and Caicos Islands, as well as on Mona Island, Puerto Rico (previously misidentified as A. argentatus ;see above) ( Fig. 18B ). On Mona Island the adults have been taken on Colubrina colubrina Millsp. (Rhamnaceae) .

Figures

Fig. 12. Apodrosus mammuthus. (A) habitus, dorsal view; (B) head, frontal view; (C) habitus, lateral view; (D) habitus, ventral view; (E) and (F) aedeagus in dorsal and lateral view, respectively; (G) spermatheca. This figure is published in colour in the online version of this journal, which can be accessed via http:// www.brill/ise

Fig. 18. Occurrences of Apodrosus species in (A) the Bahamas (Grand Bahama and Andros Island) and (B) Hispaniola, Mona Island, and the Turks and Caicos Islands.