Anchylorhynchus albidus Bondar, 1943

De, Bruno A. S. & Vanin, Sergio A., 2020, Systematic revision and morphological phylogenetic analysis of Anchylorhynchus Schoenherr, 1836 (Coleoptera, Curculionidae: Derelomini), Zootaxa 4839 (1), pp. 1-98 : 20-21

Anchylorhynchus albidus Bondar, 1943

( Figures 3I , 8B , 10C , 21B )

Ancylorrhynchus albidus Bondar, 1943b:362 (description). Lectotype (designated by Vaurie, 1954): Male; Campo Formoso, Bahia, Brazil; Bondar; in “ Cocos coronata ”. Deposited in AMNH, specimen examined.

Anchylorhynchus albidus ; Blackwelder, 1947:827 (cat.); Vaurie, 1954:26 (revision and lectotype designation); Wibmer & O’Brien, 1986:195 (cat.); de Medeiros et al., 2019, Supp. Article S2:14 (biology).

Redescription. Male: Body size (length of elytra + pronotum) 4.6 mm.

Head: Rostrum 1.4 times as long as pronotum; 1.4 times wider at apex than at base; integument black; with seven longitudinal carinae (including a pair along scrobes), two lateralmost pairs of carinae indistinct near the base; scrobes parallel to rostrum; apex covered by microsetae; areas between dorsal carinae covered by setiform brown scales, directed toward central carina. Eyes 1.5 times as high as wide; 0.8 times more separated above than below. Head with integument brown, lighter than rostrum; entirely covered by yellow scales directed to the inter-ocular fovea. Antennae with scape straight, barely reaching anterior eye margin; funicle: antennomere I only slightly wider than II, II about as long as I and about 1.5 times as long as III, VI longer than wide and narrower than club; club about as long antennomeres IV–VI of funicle. Left mandible slightly sinuate at outer margin; with one dorsal seta; outer tooth not forming a sharp angle, with somewhat blunt apex; inner tooth well-developed. Maxillae not observed. Labium with prementum almost as wide as postmentum, about 2 times as wide as long.

Thorax: Pronotum 1.5 times as wide at base as long; base slightly lobed at middle; lateral margins in dorsal view convergent and regularly curved from base to apex, with a subtle apical constriction; integument brown, similar to the head; entirely covered by uniformly yellowish scales; scales on the disk directed to center or apex. Profemur approximately 3.5 times as long as wide; dorsal margin with curvature about as pronounced as ventral margin; tooth well-defined; about 3 times as wide as protibia. Protarsus with short and dense setae on ventral surface, without sparse and long setae on the sides. Scutellum 0.9 times longer than wide; integument brown, the same color as elytra; scales yellowish. Elytra 1.4 times as wide as pronotum; 1.5 times longer than wide; 3.3 times longer than pronotum; humeri with well-defined angle; lateral margins distinctively wider at the middle; dorsal region with yellowish scales; epipleura without distinct inflexion on interval IX, covered by yellowish scales as disk. Ventral region of thorax integument brown, similar to dorsal region; scales yellowish, slightly lighter or similar to dorsal region. Hypomeron densely covered by mostly non-overlapping acuminate scales similar in shape to those in pronotum; scales next to coxal cavities with size similar to others. Prosternum length 1.0 times the coxal width; postocular lobes indistinct, with apical-lateral margin of prothorax regularly curved to slightly sinuate; densely covered by mostly non-overlapping acuminate scales narrower than those in pronotum. Metepisternum covered by non-overlapping scales, or overlapping only next to anterior margin. Metasternum central concavity distinct; with long setae in the center.

Abdomen: Ventrites III–V covered by recumbent setae. Aedeagus 2–2.5 times as long as wide; about 6 times as long as high; slightly wider at opening; with acute anterior process; ventral plate strongly sclerotized, extending to approximately 0.4 times the length of apodemes. Apodemes about 2 times as long as aedeagus. Endophallus membranous and slightly in area anterior to basal sclerite; microtrichae of the apical region not organized in bands.

Female: Body size 4.6 mm. Rostrum 1.3 times as long as pronotum; width at apex 1.5 times width at base. Eyes not measured. Pronotum 1.5 times as wide at base as long. Prosternum not measured. Scutellum 1.3 times as long as wide. Elytra 1.5 times as wide as pronotum; 1.6 times as long as wide; 3.5 times as long as pronotum. Ventrites III and IV with posterior retraction not sinuate, reaching the middle of the segment.

Remarks. This species can be distinguished by the conical pronotum with scales directed to the apex ( Figure 8B ) and the yellow body with black rostrum ( Figure 10C ) bearing poorly delimited lateral carinae near the base (as in Figure 2D ). Anchylorhynchus pinocchio has a similar color pattern ( Figures 12 B–C) and arrangement of rostral carinae, but the lateral margins of the pronotum have an inflexion in the middle and the pronotal scales are directed to the middle or to the base ( Figure 8R ). Males of the latter also have a much longer rostrum, legs and antennae ( Figures 3E , 12B , 18E ), the rostrum more than 2 times the length of the pronotum, against 1.4 times for Anchylorhynchus albidus .

Geographical Distribution. This species is only known from seasonally dry forest in the state of Bahia, Brazil ( Figure 24 ).

Host Plants. Syagrus coronata (Mart.) Becc.

Bondar (1943a) collected the specimens from Cocos coronata Mart. (junior synonym of Syagrus coronata ), and we collected it from the same species in three localities (de Medeiros et al. 2019). Even though it shares the host plant with A. trapezicollis , it is much rarer than the latter.

Examined Specimens. Type Material. BRAZIL. Bahia: Campo Formoso, G. Bondar, no date (♂ lectotype Anchylorhynchus albidus AMNH)

Other Material. BRAZIL. Bahia: Campo Formoso, G. Bondar, no date (2♀, 1♂, 1 sex undetermined AMNH) ; Itaberaba, B. A. S. Medeiros & Z. Wang, 13/XI/2014 (2 sex undetermined MZSP) ; Jequié, B. A. S. Medeiros & Z. Wang, 05/XI/2014 (3 sex undetermined MZSP) ; Maracás, F. M. Oliveira, IX/1965 (1♀, 1♂ DZUP) ; Morro do Chapéu , B. A. S. Medeiros & L. H. M. Fonseca, 15/XI/2013 (1 sex undetermined MZSP) .

Figures

FIGURE 2. Heads of species of Anchylorhynchus. Scale: 500 µm. A A. centrosquamatus, male, showing five well-defined dorsal carinae in the rostrum and scales on the head directed to the interocular fovea. B A. centrosquamatus, male, showing the pairs of lateral carinae along the scrobe, totaling 7 carinae in the rostrum. C A. pinocchio, female, showing five dorsal carinae poorly defined towards the base. D A. pinocchio, female, showing the lateral carinae poorly defined towards the base. E A. aegrotus, showing scales in the head smaller and directed to the base of the head. F A. burmeisteri, showing scales in the head directed to the rostrum. G A. tricarinatus, male, showing three well-defined dorsal carinae. H A. tricarinatus, male, showing no lateral carinae. I A. bicarinatus, male, with three well-defined dorsal carinae. H A. bicarinatus, male, with only two dorsal carinae and no central carina.

FIGURE 3. Antennae of males of species of Anchylorhynchus. Scales: 500 µm. A A. bicolor. B A. chrysomeloides. C A. variabilis D A. minimus. E A. pinocchio. F A. trapezicollis. G A. latipes. H A. rectus. I A. albidus.

FIGURE 8. Prothorax of all Anchylorhynchus species. Except for A. parcus, only known from the male holotype, the thorax of a male (left) and a female (right) are shown for each species. Arrows show the direction of scales in each position. Scale: 500 µm. A A. aegrotus. B A. albidus. C A. amazonicus. D A. bicarinatus. E A. bicolor. F A. bucki. G A. burmeisteri. H A. camposi. I A. centrosquamatus (from de Medeiros & Núñez-Avellaneda 2013). J A. chrysomeloides. K A. goiano. L A. imitator. M A. latipes. N A. luteobrunneus (from de Medeiros & Núñez-Avellaneda 2013). O A. minimus. P A. multisquamis. Q A. parcus. R A. pinocchio (from de Medeiros & Núñez-Avellaneda 2013). S A. rectus. T A. trapezicollis U A. tremolerasi V A. tricarinatus W A. vanini X A. variabilis Y A. vittipennis.

FIGURE 10. Habitus of species of Anchylorhynchus. Some images are mirrored in relation to originals. Scales: 1 mm. A A. aegrotus (male) B A. aegrotus (female) C A. albidus D A. amazonicus (male holotype) E–F A. amazonicus (Canaã dos Carajás, Brazil) G A. bicarinatus H–K A. bicolor. Photographs in K provided by Roberta Valente based on specimens loaned from NHMUK. L A. bucki.

FIGURE 12. Habitus of species of Anchylorhynchus (continued). Some images are mirrored in relation to originals. Scales: 1 mm. A A. multisquamis. B A. pinocchio (male). C A. pinocchio (female). D A. parcus (male holotype). Photographed by Johannes Bergsten © 2017 Naturhistoriska riksmuseet. Background removed from original photo, light levels and contrast adjusted. Made available by the Swedish Museum of Natural History under CC-BY 4.0 international license. E A. rectus. F A. trapezicollis. G–L A. tremolerasi.

FIGURE 18. Prolegs of species of Anchylorhynchus. Scales: 500 µm. A A. burmeisteri, male. B A. camposi, male. C A. multisquamis, male. D A. minimus, male. E A. pinocchio, male. F A. tricarinatus, male. G A. variabilis, male. H A. trapezicollis, male. I A. trapezicollis, female. J A. latipes, male. K A. latipes, female.

FIGURE 21. Male genitalia of species of Anchylorhynchus. A. parcus is known only from the holotype, which was not dissected. Scales: 500 µm. A A. aegrotus B A. albidus C A. amazonicus D A. bicarinatus E A. bicolor. F A. bucki. G A. burmeisteri. H A. camposi. I A. centrosquamatus (reproduced from de Medeiros & Núñez-Avellaneda, 2013).

FIGURE 24. Geographical distribution of species of Anchylorhynchus based on specimens examined, excluding suspicious locations as indicated in the main text. The distribution of A. parcus is unknown. A A. aegrotus, A. albidus, A. amazonicus, A. centrosquamatus. B A. bicarinatus, A. bicolor, A. burmeisteri, A. rectus. C A. bucki, A. goiano, A. imitator, A. luteobrunneus. D A. camposi, A. minimus, A. multisquamis, A. tremolerasi. E A. latipes, A. pinocchio, A. trapezicollis, A. vittipennis. F A. chrysomeloides, A. tricarinatus, A. vanini, A. variabilis.