Introduction

Despite the long history of entomological research in Hispaniola there remains a dearth of information about the diversity of Cleridae on the island. Not one species is listed from that island in the world catalogue of Corporaal (1950). I became interested in the entomofauna of this island as a result of my studies of the new world subfamily Epiphloeinae, which occur on many of the Caribbean islands.

My commitment to make knowledge available incrementally about this monophyletic lineage of the Cleridae, the epiphloeines, has involved lengthy periods of specimen accumulation. Insufficient number of specimens may at times be a considerable deterrent toward credible hypotheses of the biological species. It also minimizes the opportunity for discussions of a taxon's evolution and biogeography. This is particularly relevant among the anatomically homogeneous components of epiphloeine species (Opitz, 2004: 7). Adequately representing the full geographic range of these checkered beetles is imperative for their biological study so that a hypothesis about their species concept may be credible and, thus, their ecological role may be most usefully evaluated. Extraordinary efforts in cooperation from colleagues have greatly facilitated this goal. Their loans, exchanges, and gifts have greatly enhanced my research progress.

Elsewhere, I (Opitz, 2005: 8; 2007: 79) allude to difficulties one usually encounters in attempts to collect Cleridae, with frequent capture events of a single individual or no specimens at all. Therefore, loans from museums and private collections have been the primary source of my research material. In recent months, I was delighted to receive an assortment of checkered beetles from Robert Davidson, Michael A. Ivie, and Philip Perkins, on whose specimens this study is based.

Materials and Methods

This contribution is based on 16 adult specimens of Decorosa. Unfortunately, small sample sizes are common in taxonomic revisions of the Cleridae because species of many genera are often collected in increments of one. One specimen of D. iviei, n. sp., the type species, was completely disarticulated to establish the basic anatomical characteristics of the genus. All male specimens were dissected to determine aedeagal and spicular fork structure. The primary type specimen of Decorosa aladecoris, n. sp., was prepared with legs and antennae symmetrically arranged for photography with a Nikon DXM1200 digital camera attached to a Leica MZ microscope. The scale bar with morphological illustrations represent 1 millimeter.

The rationale to identify biological species and to predict phylogenetic relationships is similar to those expressed in earlier works (Opitz, 2006: 84. 2007: 84). I use “homoplasic apotypy” to define those characteristics that I presume evolved independently in evolutionarily distant taxa conglomerates. The rational and justification for the use of such apotypies will be addressed elsewhere (Opitz, in preparation).

Techniques of dissection, measurements, illustration, and terminology of anatomic structure are similar to those described in my previous revisionary works (Ekis, 1977: 6; Opitz, 2004: 7; 2005: 8). Label information of each primary type is presented in species descriptions in exact sequence and script as indicated on specimen labels. In descriptions, I refer to primary (1°) and secondary (2°) degree setae not in the sense that they might be used in larval ontogeny, but in the sense of physical prominence, with primary setae being much longer than the secondary setae. These setae are found on the elytral disc and are further defined as follows: primary setae are longer and more suberect than secondary setae, which are short to an extent that they give an impression of “setal mats” (Opitz, 2005: 80, fig. 260). Rows of punctations on the elytral disc are numbered such that the row nearest the sutural margin is considered row number 1. Species descriptions also include an itemization of the kinds of labels found beneath the holotype, further minimizing potential confusion of the primary type identity during future research. Specific epithets were coined or taken from the comprehensive work of Brown (1956).

Sister group relationships within Decorosa are based on principles as advocated by Hennig (1966), but I agree with Tuomikosky (1967: 138) who states that the terms apotypic and plesiotypic rather than apomorphic and plesiomorphic should be used on the grounds that evolutionary syntheses are not confined to structural character states. The apotypic or plesiotypic states of adult morphological characters are determined and organized into a character matrix. The data matrix was analyzed by hand, which represents strictly intuitive conclusions (fig. 44), and by use of NONA (Goloboff, 1993) in conjunction with Winclada version 1.00.08 (Nixon, 2002) (fig. 45).

Specimens are deposited in the following collections and copies of this contribution will be sent to their respective libraries:

Characters Selected for Phylogenetic Analysis

Fourteen anatomical characters serve to establish an intrageneric phylogenetic hypothesis of Decorosa species and to root the genus to its outgroup taxa. I relied on outgroup comparisons to establish character polarity. In this treatise, the outgroup involves members of the genera Amboakis Opitz, Ellipotoma Spinola, Hapsidopteris Opitz, Ichnea Laporte, Katamyurus Opitz, Madoniella Pic, Megatrachys Opitz, Parvochaetus Opitz, and Plocamocera Spinola. Character states identified as “0” are judged plesiotypic whereas those given a value of “1” are considered apotypic. Derived character states marked by an asterisk identify homoplasic apotypies, a type of apotypy defined under “Materials and Methods”.

Decorosa, New Genus

Type Species

Decorosa iviei, n. sp.

Diagnosis

The known geographic distribution of the members of this genus is confined to the Dominican Republic. Morphologically, the most striking synapotypic characteristic that distinguishes the members of this genus is that there has been a reduction in expression of the seventh row of elytral punctations. The seventh row is absent in the anterior third or anterior half of the elytral disc (see figs. 24, 29). Also, the funicular antennomeres are filiform, and the vertex is wider (fig. 2) than in specimens of some of the superficially similar specimens of Amboakis Opitz (2006: 22), Madoniella Pic (1935: 10), and Parvochaetus Opitz (2006: 14).

Fig. 1

Habitus of Decorosa aladecoris Opitz.

Figs. 2–11

Anatomical organs of Decorosa iviei Opitz. 2. Head (anterior view). 3. Head (posterior view). 4. Antenna. 5. Labrum. 6. Pronotum (ventral view). 7. Pronotum (dorsal view). 8. Labium. 9. Maxilla. 10. Mandible. 11. Metendosternite. Scale bars in all figures represent 1 millimeter.

Terminal palpomeres of the maxilla and labium may also be used to distinguish Decorosa specimens from those of other above-mentioned epiphloeines. For example, in Madoniella specimens the maxillary terminal palpomere is curved-subconic (fig. 36) whereas in Decorosa specimens it is curved-rectangulate (fig. 38). The labial terminal palpomere is conic in specimens of Madoniella (fig. 35), but slightly curved-conic in those of Decorosa (fig. 37). The cranium and pronotal disc are vested with short, pale, horizontally decumbent, silken setae, the elytral disc is very ornate with its pattern of yellow and brown markings (fig. 1), and the pronotum is longer than wide (fig. 7).

From superficially similar specimens of the genera Madoniella, Amboakis, and Parvochaetus, characterized by funicular antennomeres that are expanded (fig. 28), Decorosa specimens are distinguished by less bulgy eyes and a shallower medial border of the eye. Lastly, in specimens of Decorosa the epipleural fold spans the entire length of the elytra (fig. 26), which is not the case in specimens of Madoniella (fig. 27), Amboakis, or Parvochaetus.

TABLE 1

Character Matrix of 14 Morphological Characters

Description

Size: Length 3.5–5.6 mm; width 1.0–1.4 mm. Form (fig. 12): Elongate, narrow, rectangulate; pronotum elongate (fig. 7) or about as long as wide (fig. 12); elytra about three times longer than wide, epipleural margin subparallel, posterolateral margin gradually or sharply curved toward sutural margin. Integument: Cranium and pronotum light reddish brown to dark brown; elytra with intermixture of yellow and brown streaklike ornate patterns (figs. 1, 12–14); legs yellow, tibiae may be infuscated at their anterior margins; abdomen dark brown. Vestiture: Cranium and pronotum vested densely with short, pale, horizontally decumbent, silken setae, elytral disc vested with moderately stout, dark 1° setae, very uniform in length, and fine decumbent pale 2°, profusely distributed throughout elytral surface. Head: Cranium fine, rugosely punctate; eyes not very bulgy, finely faceted, ocular notch angle not acute at innermost point (fig. 2); antenna (fig. 4) inserted at lower angle of eye incision, comprised of 10 antennomeres, loosely clubbed, scape about as long as combined length of next three antennomeres, pedicel oblong, funicular antennomeres filiform, antennomeres 3–6 elongate, antennomere7 quadrate, antennomeres 8 and 9 triagonal, antennomere10 subglobose to ovate; labrum (fig. 5) deeply incised, incision bordered by eight setae; mandible (fig. 10) robust, anterior and posterior dentes well developed, mandibular penicillus poorly developed; maxilla (fig. 9) well developed, terminal palpomere curved-subconic, only slightly narrowed distally, laterolacinia present; labium (fig. 8) well developed, terminal palpomere curved-rectangular; frons planar; gula (fig. 3) subtrapezoidal. Thorax: Pronotum (figs. 6, 7) oblong or about as long as wide, pronotal lateral tubercle obtuse (fig. 12) or subacute (fig. 7); anterior margin convex, posterior margin linear, anterior transverse depression absent (fig. 1) or short (figs. 12–14), disc slightly depressed at sides where discal and paralateral trichobothria are prominent; epimeral prolongations slightly extended to middle; procoxal cavities open; elytra rectangulate, posterior portion of epipleural margin gradually or sharply rounded toward sutural margin, anterior half of disc surface macrosculptured with nine rows of punctations, posterior half macrosculptured with 10 rows of punctations, seventh row of punctations absent in basal half to basal third of disc (fig. 24); punctations large, sometimes binodal (fig. 25), and much wider than width of interstitial spaces; epipleural fold extends entire length of the elytra (fig. 26), posterior rounded portion of epipleural margin minutely spinous; metathoracic wing as in figure 23; mesoscutellum subquadrate; tibial spur formula 0-1-1, tarsal pulvilli formula 3-3-1, anterior margin of tibia with one to three spines; tarsal claws with large basal denticle. Abdomen: Six visible sterna; pygidium broad scutiform. Male Genitalia: Aedeagus short and broad, phallobasic apodeme short and broad, phallobasic rod usually tapered to a fine point, phallic plates very narrow; spicular fork as in figure 31.

Figs. 12–22

Habiti and aedeagi. 12. Habitus, Decorosa limatula Opitz. 13–14. Habiti, D. iviei Opitz. 15–18. Aedeagus, D. limatula (15, tegmen, ventral view; 16, tegmen, lateral view; 17, phallus, dorsal view; 18, phallus, lateral view). 19–22. Aedeagus, D. iviei (19, tegmen, ventral view; 20, tegmen, lateral view; 21, phallus, dorsal view; 22, phallus, lateral view).

Figs. 23–27

Anatomical organs. 23–26. Decorosa iviei Opitz (23, metathoracic wing; 24, elytra, ventral view; 25, cluster of elytral punctations; 26, elytra, lateral view). 27. Madoniella dislocata (Say) elytra, lateral view.

Figs. 28–32

Anatomical structures and body outlines. 28. Amboakis nova (Opitz) antenna. 29. Madoniella dislocata (Say) antenna. 30. A. nova body outline. 31. Decorosa iviei Opitz spicular fork. 32. M. dislocata body outline.

Distribution

This insular genus is known only from the Dominican Republic.

Etymology

The genus name stems from the Latin adjective decorus (“beautiful”) and the Latin feminine suffix -a. I refer to the stunning elytral color pattern of these beetles.

Key to Differentiate Decorosa from Amboakis and Madoniella, and Key to Species of Decorosa

Epiphloeinae checkered beetles have four trichobothria on the pronotum, two are dorsal-paralateral (fig. 33) and one occurs on each pronotal side. Also, the anterior margin of the protibiae exhibit one to many acute spines, which are not to be confused with the more coarse and obtuse spines found among some members of Enopliinae; the latter tend to be in the 8–15 mm body-size range whereas Decorosa specimens are usually about 4 mm. This key deals only with epiphloeines from Hispaniola.

1. Anterior half of elytral disc macrosculptured by 10 rows of punctations, or elytral disc somewhat roughened and densely matted with decumbent setae to extent that punctation organization poorly defined; epipleural fold extended slightly beyond middle of elytra (fig. 27); elytral disc vested with bristlelike vertical setae2

1′. Anterior half to anterior third of elytra macrosculptured by nine rows of punctations and by 10 behind middle, elytral disc never roughened or densely matted with decumbent setae; epipleural fold extended to elytral apex (fig. 26); elytral disc not vested with bristlelike vertical setae (Decorosa)3

2(1). Funicular antennomeres subfiliform, fourth and sixth slightly expanded (fig. 29); elytra usually somewhat oblong-suboval (fig. 32).Madoniella Pic

2′. Funicular antennomeres very expanded (fig. 28); elytra usually narrow-rectangulate (fig. 30).Amboakis Opitz

3(1′). Seventh row of elytral punctations begins at about basal third of elytral disc, anterior to the plane of metacoxae4

3′. Seventh row of elytral punctations begins near middle of elytral disc behind plane of metacoxae (fig. 24)5

4(3). Cranium and pronotum uniformly dark brown; elytral markings as in figure 1 (Dominican Republic: La Vega).Decorosa aladecoris, n. sp.

4. Cranium and pronotum not uniformly dark brown, cranium narrowly reddish, brown at margins of eyes, pronotum narrowly red brown along anterior margin (Dominican Republic: San Juan).Decorosa neiba, n. sp.

5(3′). Pronotum narrow (figs. 13–14); apex of anterior protibial margin of right tibia with one stout spine; pronotal lateral tubercle subacute (fig. 7); elytral disc markings as in figures 13–14 (Dominican Republic: San Juan: Santiago).Decorosa iviei, n. sp

5′. Pronotum broad (fig. 12); pronotal lateral tubercle obtuse (fig. 12); apex of anterior protibial margin of right tibia with 2 spines; elytral markings as in fig. 12 (Dominican Republic: Azua).Decorosa limatula, n. sp.

Description of Decorosa Species

Figs. 33–38

Anatomical structures. 33. forebody of Madoniella dislocata (Say). 34. Aedeagus of Decorosa aladecoris Opitz. 35–36. Madoniella dislocata (35, terminal labial palpomere; 36, terminal maxillary palpomere). 37–38. D. iviei Opitz (37, terminal maxillary palpomere; 38, terminal labial palpomere.

Figs. 39–43

Anatomical organs and habitus. 39. Decorosa aladecoris Opitz elytra, ventral view. 40–41. D. neiba Opitz (40, aedeagus; 41, habitus). 42. D. aladecoris, pronotum. 43. D. neiba, pronotum.

Fig. 44

Phylogenetic tree of Decorosa Opitz and related taxa; manually prepared.

Review of Greater Antillean and Hispanioloan Paleogeography

The literature is rich in facts, ideas, and syntheses about Caribbean biogeography/geology (Schwartz, 1980; Rosen, 1985; Liebherr, 1988; Mann et al., 1991; Donovan and Jackson, 1994; Woods and Sergile, 2001, and references therein) and more specifically about insect Hispaniolan zoogeography such as Woodruff and Sanderson (2004: 26). These stimulating contributions inspire attempts to make biographical sense of one's taxonomic findings. My intent for this review of Antillean paleohistory is to provide a baseline of thoughts, along with additional comments related to insect findings, and summary for this and future analyses of Caribbean Cleridae taxa.

There is strong evidence from geology (Khudoley and Meyerhoff, 1971: 129; van Fossen and Channell, 1988: 610; Perfit and Williams, 1989: 67; Heubeck et.al., 1991: 29; Draper et al.,1994: 143) and biology (Williams, 1961: 2; Schwartz, 1980: 87, 1989: 489; Rosen, 1985: 652; Liebherr, 1988: 143; Woodruff and Sanderson, 2004: 27) to support the hypothesis that Hispaniola was once comprised of two islands, and that the northern part originated from an early Cretaceous-Eocene assemblage of insular rock whereas the southern portion originated from oceanic plateau rock, essentially the uplifted edge of Caribbean sea crust (Draper et al., 1994: 129). The two-island hypothesis and the prehistoric movement of the two landmasses that constitute Hispaniola have been incorporated into a paleogeographic model of West Indies mobility (Pindell and Dewey, 1982: 202; Sykes et al., 1982: 10,669; Wage and Burke, 1983: 633; Rosen, 1985: 652; Perfit and Williams, 1989: 67; Pindell and Barrett, 1990: 405).

To explain biologic relationships between the northern and southern elements of Hispaniola, and those between Hispaniola and any other West Indies landmass, we must explore what is known about the geology and the paleotectonic and neotectonic events that eventually led to the island's amalgamation. Moreover, the relative geologic ages of the two prehistoric landmasses is relevant to any discussion of their biogeography.

Donnelly (1988: 26) places the initial emergence of Greater Antillean terrain during the upper lower Cretaceous, about 105 Ma with Hispaniolan and Jamaican rocks included in the mix. Khudoley and Meyerhoff (1971: 152) suggest that “Most of the Greater Antilles were uplifted in the Miocene and later times.” Early Cretaceous rock elements in northern Hispaniola and late Cretaceous rock elements for the southwestern part of the island were reported by Draper et al. (1994: 129). This suggests that at least some portions of the crustal component of the Hispaniolan northern island may be more ancient than its southern counterpart. Rocks of the late upper Cretaceous (Maastrichtian stage, about 70 Ma) have been reported as a component of the southwestern Sierra de Bahoruco (Draper et al., 1994: 139). Of considerable relevance to the question of age of the southern portion of Hispaniola is the gymnosperm and angiosperm fossil discovery by Woodruff (1986: 32; also see Woodruff and Fritsch, 1989: 216) from the Larimer deposits of the Sierra de Baoruco considered Cretaceous by De Leon (1989: 85).

Fig. 45

Phylogenetic tree of Decorosa Opitz and related taxa; computer generated.

Fig. 46

Geographic distribution of Decorosa Opitz species.

It has been hypothesized that Hispaniola's southern terrain was in proximity with the Yucatán peninsula (Rosen, 1985: 644) during early Eocene to late Paleocene (from 50–65 Ma) and that crustal movements, involving fault generated tectonics, between the Caribbean and North American plates carried southern Hispaniola to its eventual welding with the northern Hispaniolan component; an amalgamation purported to have occurred during early Miocene (about 20 Ma) (Heubeck et al., 1991: 29). Depending on one's starting point, this means that the two islands have been separated from 35 to 85 million years of Caribbean evolution. And, while both islands experienced tumultuous geologic changes (Donnelly, 1988: 27), likely environmental stresses from a bolide impact (Hedges, 2001: 19; Opitz, 2005: 108), and presumably vicissitudinous climates (Clench, 1963: 257), which must have had significant impacts on speciation and extinctions (Curtis et al., 2001: 50; Morgan, 2001: 398), the aforementioned time span represents a wide window of opportunity for independent biologic evolution.

Moreover, during their eastward tectonic journey, the terrestrial components of Hispaniola would have experienced the kind of fault-based shifting and rotation that would have placed them in close geographic relationships with other Greater Antillean terrain. Draper and Barros (1988: 60, 1994: 82) suggest late Eocene geologic ties between Cuba and Hispaniola and based on Lygaeidae findings Baranowski and Slater (1998: 75) suggests vicariance between Cuba and Hispaniola, and possibly Puerto Rico. In a treatise of plant phylogeny involving trees and shrubs of Lyonia (Ericaceae), Judd (2001: 72) discusses geologic relationships between western Cuba and southwestern Hispaniola and biotic relationships among Puerto Rico, north-central Hispaniola, and eastern Cuba.

If the welding of northern and southern Hispaniola occurred some 20 Ma (Heubeck et al., 1991: 29) and speciation events requires about 3 million years, as suggested by Whitehead (1972: 308) in his work with ground beetles, then biologists interested in Hispaniolan beetle evolution have some measure for the temporal character of lower taxa divergence. This would be particularly useful for temporal analyses involving sister-group relationships between northern and southern Hispaniola and vicariant relationships among taxa from Hispaniolan and those of other Greater Antillean terrain.

Decorosa Evolutionary Considerations

Two phylogenetic trees (figs. 44 and 45) were produced for Decorosa, one (fig. 44) prepared “by hand” and the other (fig. 45) computer generated. The computer analysis generated one parsimonious tree of 29 steps, CI of 100, and an RI of 100. Both phylogenies produced identical pairs of Decorosa sister species.

Paucity of Decorosa specimens and few distributional records usually preclude comprehensive discussion about phylogeny and zoogeography. But even a few tentative comments might be beneficial for future endeavors about the subject. Hispaniola has benefited from a flurry of entomological activities in recent years (Schwartz, 1989: 489; Woodruff and Sanderson, 2004: 1; and various communications with insect collectors) and there has evolved a greater awareness of insect diversity in the Caribbean (Liebherr, 1988). Some of these activities include greater insect collecting efforts, which have resulted in greater availability of Cleridae specimens.

The four Decorosa species are known only from the northern highlands of Hispaniola (fig. 45) with D. limatula, the sister species of the more northern D. iviei found in highlands east of Sierra de Neiba slightly north of the Enriquillo basin. Decorosa aladecoris and D. neiba, the more primitive members of the genus, are undoubtedly sympatric with the most derived D. iviei, which at the very least suggests some dispersal element in the early history of the genus.

As D. limatula is known from environs slightly north of the Enriquillo basin, one might presume a vicariant relationship between D. limatula with the more northern sister species D. iviei, as is the case between D. aladecoris and D. neiba. Discovery of limatula specimens from south of the Enriquillo basin would certainly support that possibility, and corroborate the likely north-south vicariance findings of Mertens (1939: 12), Williams (1961: 2), Schwartz (1980: 90), Judd (2001: 69), and Woodruff and Sanderson (2004: 26). As the most primitive members of the genus were collected from the northern portion of Hispaniola, I suspect that the northern component of the two paleoislands served as the ancestral terrain of the genus in which ancestral Decorosa stock B diverged to produce the aladecoris-neiba lineage and the more derived limatula-iviei lineage (fig. 44). More widespread northern collections of additional D. aladecoris and neiba specimens or absence of such material from the southern island would support the hypothesis and more credibly root the initial geographic divergence of the genus. Sister-group relationships of insect taxa between these two formerly insular highlands have been confirmed in Scarabaeidae (Woodruff and Sanderson, 2004: 26) and in butterflies (Schwartz, 1989: 489; Sourakov, 2000: 79).

The putative absence of Decorosa from western and southwestern Hispaniola could be a consequence of collecting bias or simply that captured specimens are unknown to me. I, like many other biologists, fear that extensive deforestation has eliminated a substantial Hispaniolan insect fauna, especially from western portions of the island (Sergile and Woods, 2001: 547).

The divergence of ancestral Decorosa yielded the aladecoris line, which retained several primitive characteristics including normal eye size and nonnodal elytral punctations while acquiring an apotypic convex pronotum and loss of the pronotal anterior transverse depression. The sister taxon of this lineage, ancestor C, would have evolved a more flattened pronotum, the eyes became significantly reduced, and the elytral punctations acquired a binodal characteristic. This ancestor eventually yielded D. limatula and D. iviei each characterized as indicated in fig. 44. It remains to be seen whether D. limatula dispersed to southern portions of prehistoric Hispaniola from northern ancestral grounds, or whether the north-south distribution record of the limatula-iviei lineage expresses some manner of disjunction between the paleoislands of Hispaniola.