Two new endemic species of Chrysopodes ( Neosuarius ) ( Neuroptera , Chrysopidae ) from the Galápagos Islands

Two new species that were previously undistinguished from the Galápagos endemic Chrysopodes (Neosuarius) nigripilosus (Banks), are described. Th ese descriptions double, from two to four, the number of endemic green lacewing species known from the archipelago. Th e four species include: Chrysoperla galapagoensis (Banks), Chrysopodes (N.) nigricubitus sp. n.; C. (N.) nigripilosus; and C. (N.) pecki sp. n. Th ree of these species – C. (N.) nigripilosus, C. (N.) nigricubitus and Chrysoperla galapagoensis – each occur on more than one island, whereas C. (N.) pecki is known only from the summits of two craters on Isabela Island. A suite of very distinctive features diff erentiates the three Galápagos Chrysopodes (N.) species from their congeners on mainland South America. Subtle, but consistent characteristics separate the three Galápagos species from each other. Th e small degree of morphological divergence among the Galápagos lacewings is in marked contrast to the spectacular radiation of Hawaiian lacewings; the processes of diversifi cation and speciation may diff er signifi cantly between the two island archipelagos.


Introduction
Th e diversity of insect species reported from the Galápagos Islands is relatively low (e.g., Linsley and Usinger 1966;Parkin et al. 1972;Peck 2001); this generalization appears true for the green lacewings (Chrysopidae).In the most recent synopsis of the Galápagos fauna, Peck (2001) listed only four species: (a) two endemics [Chrysoperla galapagoensis (Banks, 1924) and Chrysopodes (Neosuarius) nigripilosus (Banks, 1924)] and (b) two others with broad distributions in Central and South America [Chrysoperla externa (Hagen, 1861) and Ceraeochrysa cincta (Schneider, 1851)].Both endemic species are known from several islands in the archipelago, and despite numerous scientifi c expeditions, no new endemic chrysopid species have been described since Neuroptera were fi rst recorded from the Galápagos (Banks 1924).
For several reasons, we considered the possibility that additional species of chrysopids might occur on the islands.First, Banks ' (1924) relatively brief description of C. (N.) nigripilosus was based on a small series of specimens from one island, and it was written before the systematic value of male or female genitalia were generally appreciated.Second, since Banks' original treatment of the Galápagos lacewings in 1924, a small but substantial number of specimens has accumulated in museums, but no further systematics work has ensued.Th ird, one of the endemic species [C.(N.) nigripilosus] is well diff erentiated from its closest relatives on the western South American mainland (Tauber, in press).Th is species' high level of diff erentiation and its broad inter-island distribution would be consistent with a relatively long evolutionary history on the islands.Given the relatively rapid rates of speciation among Hawaiian lacewings (Zimmerman 1957, Tauber et al. 2007), we hypothesized that cryptic species may be sequestered within the single recognized Galápagos Chrysopodes species.And, we thought it especially timely to examine this hypothesis during the celebration of Darwin's bicentennial.
To begin our study, we examined all of the Chrysopodes specimens originating from the Galápagos archipelago that we could obtain from museums and compared them with the types of C. (N.) nigripilosus.We found that these specimens share many external traits (general body color, size, head and wing features) and that they also have a common suite of genital characters that distinguish them from the other (mainland) species of Chrysopodes (Neosuarius) (Tauber, in press).Furthermore, our study revealed that the specimens express subtle variation that, for the most part, appears consistent with intraspecifi c (geographic) variation in C. (N.) nigripilosus; however, in two cases, the variation is strongly indicative of new species.
Here, we (1) re-describe C. (N.) nigripilosus from the type locality (Baltra) and (2) characterize the variation in the available specimens of this species from four other islands (Santa Cruz, Isabela, Fernandia, Santa Fe).Finally, (3) we describe two new Chrysopodes (Neosuarius) species that our study diff erentiated from C. (N.) nigripilosus -one from Santa Cruz and Pinta Islands, and another from two Volcánoes on Isabela Island.

Materials and methods
Th e Chrysopodes specimens from the Galápagos Islands that we studied came from the following collections: American Museum of Natural History, New York (AMNH), Museum of Comparative Zoology, Harvard University, Cambridge, MA (MCZ), Bernice P. Bishop Museum, Honolulu (BPBM), California Academy of Sciences, San Francisco (CAS), National Museum of Natural History, Smithsonian Institution, Washington, D.C., formerly United States National Museum (USNM), the Institut Royal des Sciences Naturelles de Belgique, Bruxelles, Belgium (IRSNB) and the National Museum of Scotland, Edinburgh (NMS).
It is noteworthy that most of the pinned specimens that were available are relatively discolored.Th e discoloration is accentuated because the integument of Chrysopodes (Neosuarius) species tends to have a heavy coating of waxy material (probably an adaptation to arid conditions); often the coating becomes brownish over time.In contrast, the markings on the specimens that were stored in alcohol (those from the IRSNB) are well preserved and readily visible, in part because the waxy material was dissolved.Th us, our reports of head and body color relied heavily on the specimens preserved in alcohol; our observations from pinned specimens should be considered as estimates.

Chrysopodes (Neosuarius) of the Galápagos Islands
Th e Galápagos Chrysopodes (Neosuarius) are generally of a similar, relatively medium size; wing length ranges from ~10.2-13.7mm.Th ey are also alike in coloration, i.e. tan to light brown bodies with darker brown mottled markings, cream-colored to light brownish heads with dark brown facial markings, hyaline wings with a relatively narrow costal area and white and dark brown venation in a typical C. (Neosuarius) pattern (Tauber, in press).
In the above, and several other internal and external traits, the Galápagos Chrysopodes (Neosuarius) are most similar to the fl avescens group of C. (Neosuarius) species on the mainland (Tauber, in press).However, our study here shows that the Galápagos specimens share a suite of unique genital characters that distinguish them from the mainland species.For example, they are the only C. (Neosuarius) in which the males have a pair of large, eversible pouches (probably pheromonal) that extend posterolaterally from the membrane at the tip of the terminal abdominal sternite, and a pair of elongate, setose, ducts that originate within the gonosaccus (immediately below the mediuncus) (Figs 9c,10c,11c).Th e interior of the ducts appears grainy; the ducts may be glandular.
Like other species in the fl avescens group, the Galápagos females have a distinctive, tubular spermatheca; the spermathecal duct is short and lightly sclerotized (Fig. 13).Th e bursa is leathery and moderately large (it covers the spermatheca), and the bursal glands are bulbous and bear elongate accessory ducts (Fig. 13).Th e spermathecae of the three endemic Chrysopodes (N.) species are unique in that they have a very small mesal swelling and are only slightly bent; they lack the bean-shaped enlargements, coils and sharp bends that characterize the spermathecae of the mainland species.
Th ese numerous synapomorphies provide strong evidence that the extant Chrysopodes (Neosuarius) on the various Galápagos islands have a common evolutionary history of diff erentiation from an ancestral species that immigrated to the Galápagos from the South American mainland.(Banks, 1924) Diagnosis.Chrysopodes (Neosuarius) nigripilosus specimens from the type locality (Baltra, = South Seymour; all pinned) are distinguished by their overall tan to light tan body color; the pleuron, venter and legs are largely light tan to cream-colored.Th e vertex is light brown and the facial markings range from light to dark brown (Fig. 1).Th e forewing membrane is without markings or suff usion; below the stigma there usually are three to four (occasionally two) crossveins between the Subcosta and Radius, (scx); and the second cubital crossvein (cux2) is not bent or crassate, nor does it have an enlarged swelling (Fig. 4a).Th e venter of the male abdomen is largely cream-colored to light tan throughout; in contrast, the female S5 and S6 are entirely brown, S7 is either brown entirely or basally, and the terminus is light to dark brown (Fig. 6a, b).

Chrysopodes (Neosuarius) nigripilosus
In the males: (a) the horizonal apodeme along the ventral margin of T9+ectoproct is arched and its posterior tip is bifurcated (see Note in brackets below); (b) the gonarcus is arcuate, with the gonarcal arms extending downward, not outward (Fig. 9b, c); (c) the eversible pouches at the tip of S8+9 are large and well separated mesally by a distinctly fl at membrane (Fig. 8).In the female, the spermathecal duct is short and it lacks tight coils; the bursal glands are large and globose and their accessory ducts may be branched (Figs 13,14).Th e subgenitale bears a pair of invaginated pouches that are near the base of the bursal glands; in C. (N.) nigripilosus, these pouches typically are fl at and folded (Fig. 15a).
[Note: In Chrysopidae the apex of the abdomen is opened by two major apodemes articulating with each other at their bases.One apodeme runs along the ventral portion of tergite 9+ecoproct; it is termed the dorsal apodeme (d.a.).Th e other apodeme runs along the dorsum of sternite 8+9 and is termed the ventral apodeme (v.a.).Th e dorsal apodeme can be complex, with a dorsal branch (d.b.) along or below the anterior side of the callus cerci, a ventral branch (v.b.) that projects ventrally towards the gonarcus, and a caudal branch (c.b.) that extends distally below the callus cerci and can project beyond the ectoproct.]Description of specimens from type locality.Head.(Table 1, Fig. 1a, b, c): Vertex raised, fl at, pentagonal shape, with small, upward fold posteriorly; surface of vertex with small, brown setae.Frons smooth, shiny throughout.Clypeus convex basally; surface smooth, mostly fl at, very slightly raised in middle.Labrum fl at, surface smooth; distal margin straight.Gena smooth, rounded.Coloration: Frons light tan to light brown with pair of brown, subtriangular to roundish marks below toruli; clypeus with lateral margins dark brown.Vertex brown.Toruli light brown, with surrounding sclerotized areas brown to dark brown; dorsal torulus with two dark brown, vertical streaks, larger one extending from below center of scape, smaller one extending from below mesal margin of scape.Genae dark brown, central area with large to small, longitudinal, pale stripe.Scapes light brown to tan, unmarked; pedicel brown basally, lighter distally; fl agellum light brown.Maxillary palp: segments 3-5 brown; basal two segments tan.Labial palp with terminal segment brown, basal segments tan.Venter tan to cream-colored; lateral margins of submentum dark brown.Th orax.(Table 1, Fig. 1b).Pronotum tan to light brown, with scattered, brown, mottled markings sublaterally; several long, thin, pale setae laterally, short, robust, dark brown to black setae dorsally.Mesonotum, metanotum light brown mesally, brown laterally; setae on mesonotum short, robust, dark brown; setae on metanotum sparse, thin, pale.Pleural areas tan to cream-colored, sometimes with brown markings.Legs cream-colored without markings, setae light brown.Tarsal claws amber, long, narrow, with broad cleft, small base; area between claws black.
Hindwing narrow, length over three times greater than height, with apex acute.Ten to eleven radial crossveins; three to fi ve inner gradates; six to seven outer gradate veins; three b cells; no t cell; four b' cells; two intracubital cells, distal one open.
Forewing hyaline, with stigma slightly opaque; costal veinlets within stigma brown, surrounded with suff usion of light brown.Alar membrane almost completely without suff usion of colored pigment.Longitudinal veins cream-colored, marked with dark brown to black at intersections with crossveins.Most costal veinlets, almost all crossveins cream-colored in center, dark brown at tips.Gradates dark brown to black; terminal veinlets dark brown basally, brown at tips, with cream-colored sections mesally.Rs black at intersection with Rx1; ma black; Cu black at furcation; marginal cell below 3A almost completely dark brown to black.Hindwing hyaline; membrane without suff usion of colored pigment; stigma opaque, brownish.Longitudinal veins cream-colored, marked with dark brown at intersections with crossveins; gradates, icu crossvein dark brown; costal veinlets, most crossveins dark brown at tips, cream-colored in center.
[Th e origin of the fl uted area below the bursa is not completely clear.We consider it to be an enlarged part of the bursal duct and label it as such on the fi gures.However, we recognize that it could be part of the bursa copulatrix, in which case the bursal duct would be greatly reduced.]Spermatheca elongate, tubular, with distal end slightly bulbous, one bend, after midsection (to the right), open to bursa via elongate dorsal slit throughout; 0.12 mm diameter at mouth (distal end), 0.18 mm diameter in midsection (widest area), 0.5-0.6 mm long; invagination oblong, extending ~1/2 length of spermatheca (length 0.23-0.25 mm); velum not identifi ed.Spermathecal duct short, not well sclerotized at tip, ~0.65 mm long (not including pale, brushy tip), extending from slit on dorsal margin of spermatheca, curving, entering subgenitale, making U-shaped curve along dorsal surface of subgenitale cavity, then looping in front of spermatheca; distal ¼ brushy.Colleterial gland elongate, narrow, extending slightly into A6, with smooth, untextured surface, base with bulbous, folded reservoir near terminus of duct; no accessory glands found.
Transverse sclerifi cation curved, eliptoid, plate-like, located mesally within gonopophyses laterales, with two rows of setae (setae longer mesally than laterally).Intraspecifi c variation.See measurements (Tables 1, 3).Baltra.Th e lectotype (AMNH) is teneral.It has a mediuncus that is characteristic of mature specimens, but the gonarcal arms are barely formed, the glandular ducts are visible only in a small region at the base of the gonarcal arms, and the eversible pouches are small and withdrawn.Th e dissected paralectotype (MCZ) is mature, with structures as described above.
Santa Cruz (Academy Bay).Th e large series of specimens from this locality are relatively uniform, and in all the features that we measured, they overlap with those from the type locality.Although they tend to have somewhat longer wings (Table 3), their head size and proportions, as well as the features of the wings, are well within the range of the Baltra specimens (Tables 1, 3).
Th e dorsal surface of specimens from Academy Bay is relatively dark (light brown to brown); the lateral and ventral surfaces of the thorax are light brown to tan; dorsally the abdomen is cream-colored to light brown, with areas marked with brown; ventrally the abdomen is cream-colored to light tan (entirely in the males; with S5, S6 and S7 brown in the females).Th e facial markings range from medium depth to dark.Th e membrane of the wings is without markings or suff usion; the degree to which the Rs, ma and Cu are thickened is small; and there are three to four crossveins below the stigma.In the four dissected males, (a) the gonarcal arms are oriented downward; (b) the eversible pounches are large and well separated.[Note: One of the ~65 specimens has a small amount of suff usion around the gradates and some crossveins, but none of the other characteristics of C. (N.) nigricubitus; four of 65 specimens (from the 1968 Edinbrough University Expedition) have two crossveins below the stigma; of these, two have three crossveins on the opposite wing.] Isabela.Th e C. (N.) nigripilosus specimens from Isabela overlap with the Baltra specimens in the features we examined.Among these specimens (both pinned and in alcohol), there were no distinguishing features with regard to head size, head features, or wing size or wing features (See measurements, Tables 1, 3).
Th e overall body color is tan with mottled, light to medium brown dorsal markings; the ventral abdominal markings of the males and females match those of the Baltra population.Th e facial markings range from light to medium brown.Th e membrane of the wings is without markings or suff usion; the degree to which the Rs, ma and Cu are thickened is small; and there are three to four crossveins below the stigma.On the two dissected male specimens from this island: (a) the gonarcal arms extend downward from the gonarcal bridge, parallel with the mediuncus, and (b) the eversible pouches are short and highly folded; although they are fully separate, the area between them is membranous and loose.
Fernandina.In general, the specimens from this island (2 pinned and 7 in alcohol) overlap with the Baltra specimens.Th e degree to which the Rs, ma and Cu are thickened is small; the membrane of the forewing is clear and without marks; there are three crossveins below the stigma (Table 3).
Santa Fe, Santiago.Th e single female specimens from Santa Fe and Santiago Islands have features that are typical of the Baltra population (Tables 1, 3). ) pecki: they have small, robust, brownish bodies, brown head and facial markings, relatively narrow wings with a narrow costal area, and cream-colored wing venation marked with black (Figs 1, 2, 4).However, a suite of distinguishing features (external and internal) in both males and females indicates that these specimens represent a distinct species.Th e most prominent distinguishing feature of the species is the suff usion of black or dark brown pigment (coloration) around many of the crossveins on the forewings (Figs 4b,5b).Th is suff usion is absent from the other two Chrysopodes species on the Galápagos Islands.In C. (N.) nigricubitus, the second cubital crossvein bears a distinct, dark brown to black swelling that is absent from C. (N.) nigripilosus and small on C. (N.) pecki.Also, there are consistent diff erences between the species in the length : width ratios of the pronotum and abdominal tergite 6; for both structures, the C. (N.) nigricubitus ratios are intermediate between those of C. (N.) nigripilosus and C. (N.) pecki (Tables 2, 5).Among the specimens that we studied, there was no overlap between the species in the values of any of these traits.In addition, the abdominal sternites of female C. ) nigripilosus it is forked, with both tips rounded, and with the upper fork having a fl angelike membrane attached (Fig. 10a).
In the female genitalia, we detected small, but consistent diff erences between C. (N.) nigricubitus and the other two Galápagos species.First, the sclerotized portion of the C. (N.) nigricubitus spermathecal duct tends to be slightly shorter than that of C. (N.) nigripilosus (0.65 vs. 0.40 mm) (Table 5).Second, the tip of the distal knob of subgenitale is slightly more elongate than that on the two other species, and, third, the pouches near the base of the bursal glands are fl at and folded as in C. (N.) nigripilosus but not C. (N.) pecki (Compare Fig. 15b with 15a, 15c).
Description.All features are as described for C. (N.) nigripilosus except as follows.Head (Table 2, Fig. 2): Vertex: surface with small, amber setae.Labrum: distal margin with slight mesal cleft.Coloration.Head cream-colored frontally, tan to light brown dorsally, with brown streak lateral to eyes; frons with pair of oblong, brown marks below most of lower margin of torulus; clypeus with lateral margins dark brown; toruli cream-colored to light tan, with brown border surrounding sclerotized margins; dorsal torulus with dark brown, vertical streak.Genae dark brown ventrally, white stripe above, dark brown dorsally.Scapes tan, unmarked; pedicel tan to light brown; fl agellum light brown.Maxillary palp: basal two segments cream-colored.Venter: lateral margins of submentum cream-colored to tan.
Wings (Table 4,Figs 4b,5b).Costal area: greatest height ~0.16-18 times height of wing; tallest at costal cell (#4-6).Subcosta: two subcostal crossveins below stigma.Nine to eleven radial crossveins (between R and Rs); ma considerably more thickened than the Rs at rx1; two rows of gradates; inner row with three to four gradates, outer row with fi ve to six, both rows in regular pattern.Cubitus thickened near furcation; icux2 curved, with dark brown, bubble-like expansion mesally.Hindwing: length approximately three times height.Nine to eleven radial crossveins; three to four inner gradates; fi ve to six outer gradate veins; three b cells; t cell usually present.
Forewing: alar surface surrounding many crossveins with suff usion of brown to dark brown.Stigma very slightly opaque; costal veinlets within stigma brown to black.Base of Rs, rx1 dark brown to black; icux2 dark brown to black, with dark brown, bubble-like swelling mesally.Hindwing: stigma very slightly opaque; veinlets within stigma, dark brown, with dark brown pigment in surrounding area; gradates, icux2 cream-colored to light brown.
Specimens examined.Type material only.Intraspecifi c variation.Th e variation among the specimens we studied is small.See Tables 1, 3 & 5 C. (N.) pecki adults may also be characterized by an elongated pronotum.Both female specimens (preserved in alcohol) have a pronotum that is longer than that on C. (N.) nigripilosus (Table 2), and the C. (N.) pecki pronotal length : width ratio is C. (N.) pecki males have abdominal sclerites and genitalia that generally resemble those of C. (N.) nigripilosus and C. (N.) nigricubitus (Fig. 11).However, there are some distinguishing features.First, the size of the gonarcus (length of arms, bridge width) is larger than that of either C. (N.) nigripilosus or nigricubitus (Table 5).And, the lateral arms of the gonarcus are directed inward next to the mediuncus as in C. (N.) nigripilosus (Fig. 11b, c).Second, as in C. (N.) nigricubitus, the dorsal apodeme along the ventral margin of T9+ectoproct is relatively straight, and the caudal branch has a well sclerotized, unforked, pointed tip (Fig. 11a).However, in C. (N.) pecki the tip has a small, beak-like fl ange with a membrane attached (not visible on Fig. 11a).Th ird, unlike either of the other species, the ventral branch of the dorsal apodeme is elongate, well sclerotized, and angled anteriorly; distally it turns and invaginates within S8+9 (Fig. 11a).And, fourth, although the dorsal apodeme itself is thin (lateral view), the base of the dorsal branch (that extends under the callus cerci) is heavy and densely sclerotized.
In addition to the ventral marks on the abdomen, we detected some other characteristics that distinguish the female terminalia of the C. (N.) pecki specimen we examined.First, the sixth and seventh tergites were slightly longer in actual length, and in their length to height ratio, than those on any of the C. (N.) nigripilosus or C. (N.) nigricubitus specimens (Table 5).Second, as in the two other species, the membrane that is basolateral to the subgenitale bears a pair of invaginated pouches that are near, but separate from, the base of the bursal glands.In C. (N.) pecki, these pouches are clear and bulbous, not fl at and folded as in the other two species (Fig. 15c).In all other traits, the female that we measured tended to be large, but the measurements overlapped with those of large C. (N.) nigricubitus specimens.) nigripilosus except as noted below.Head (Table 2; Fig. 3).Vertex: surface with small, amber setae.Labrum: distal margin with slight mesal cleft.Coloration.Head cream-colored frontally, lateral to eyes, tan dorsally; frons with pair of triangular to bowl-shaped, dark brown marks below torulus; clypeus with lateral margins dark tan, dark brown streak extending dorsolaterally from distal margin of tentorial pits almost to eye; toruli cream-colored, with light tan border surrounding sclerotized margins; dorsal torulus with or without grape-brown, vertical streak.Genae cream-colored with dark brown on ventral margin, dark brown dorsally.Scapes tan, unmarked; pedicel tan to light brown; fl agellum tan.Venter: basilateral margins of submentum dark brown.
Hindwing narrow, length approximately three times height.Ten radial crossveins; four inner gradates; six outer gradate veins; three b cells; t cell present.
Forewing hyaline, very slight suff usion of brown to dark brown coloration around Rs at intersection with rcx1, fi rst outer gradate, Cu near icu2.Subcostal crossveins within stigma brown, surrounded with dark brown suff usion.Costal veinlets, gradates dark brown to black; ma1 black; icux2, small bubble-like swelling dark brown to black; marginal cell below 3A partially dark brown.Hindwing: stigma slightly opaque, veinlets within stigma brown, with brown pigment in surrounding membrane; icux2 cream-colored to light brown.
Etymology.Th e species is named in honor of Stewart B. Peck, Carlton University (Canada), in recognition of his contributions and devotion to the study of Galápagos insects.
Specimens examined.Type material only.Intraspecifi c variation.Sample size very small, but see Tables 2, 4, and 5.

Undetermined specimen
Th ere is a single specimen from Floreana (a male) that we were unable to place within any of the three species.Externally, it is very similar to C. (N.) nigripilosus, but the genitalia, in part, resemble those of C. (N.) nigricubitus and in part, they are unique.Specifi cally, the head coloration and markings are very similar to those of C. (N.) nigripilosus from Baltra; the dorsum is largely light brown and the pleural and ventral regions appear to be cream-colored as in the Baltra and Isabela populations.Th e membrane of the forewing has no markings or suff usion of pigment; the size and pattern of venation and thickened veins do not diff er from those of C. (N.) nigripilosus; there are three crossveins below the stigma.Th e genitalia resemble those of C. nigricubitus in that the gonaracus is relatively fl at; the gonarcal arms extend laterally from the gonarcal bridge; and only the tips of the gonarcal arms bend downward toward the mediuncus.However, unlike any other specimens we have examined, the eversible pouches at the tip of S8+9 are relatively short, tapered distally, juxtaposed and partially fused mesally, and the membrane between the pouches is loose and large.Further study, especially analysis of the reproductive pheromones, might demonstrate that this is yet another undescribed, cryptic species.

Discussion
Th e Galápagos lacewings.Th e two new cryptic species previously nestled within C. (N.) nigripilosus indicate that the Galápagos lacewing fauna may not be impoverished to the degree originally estimated.Th e number of named, endemic Galápagos Chrysopodes lacewings has increased from one to three species, and the possibility of another exists.Although clearly distinct, the Galápagos lineage of Chrysopodes shows marked af-fi nities with the Chrysopodes (Neosuarius) fauna of the western Andean region -particularly the C. (N.) fl avescens group to which it has been assigned (C. A. Tauber, in press).
Overall, including Chrysoperla [Chrysoperla galapagoensis (Banks, 1924)], four endemic chrysopid species are now documented from the Galápagos Islands.In addition, an endemic brown lacewing (Hemerobiidae) has been reported (Megalomus darwini Banks 1924) (Peck 2001).It is noteworthy: like many endemic Galápagos species of insects, at least four of the fi ve endemic lacewings occur on more than one island.Th us, the pattern of a relatively depauperate, endemic arthropod fauna with broad inter-island distributions, noted by Linsley and Usinger (1966), Parkin et al. (1972), andPeck (2001), remains true for the Galápagos lacewings, but the number of recognized species has increased.
Each of the lacewing families is also represented by non-endemic, broadly ranging species on the Galápagos archipelago -Chrysopidae: Chrysoperla externa (Hagen, 1861) and Ceraeochrysa cincta (Schneider, 1851) and Hemerobiidae: Sympherobius barberi (Banks, 1903).All three of these species occur throughout Central and South America; one is also wide-ranging in the Pacifi c region.All are found on many of the Galápagos islands.[Note: C. cincta was erroneously reported to be endemic to the Galápagos Islands (Baert et al. 1992, Peck 2001); however, its distribution extends throughout Central and South America (Adams and Penny 1985).] Comparison with the endemic lineages of Hawaiian lacewings.Statements regarding the low diversity of the Galápagos biota are particularly intriguing when the lacewings of the Galápagos are compared with those of another isolated Volcánic archipelago in the Pacifi c -the Hawaiian Islands.Hawai'i's extant endemic green lacewing fauna (Chrysopidae) consists of a single radiation of approximately 20 species in the monophyletic genus, Anomalochrysa.Among the endemic Anomalochrysa, 14 species are found only on a single island and only four species occur on three or more islands (Zimmerman 1957).
Hawai'i's endemic brown lacewing fauna (Hemerobiidae) consists of a similarly sized group of Micromus species that is presumed to be a single, monophyletic lineage.Among these species, sixteen are restricted to a single island and eight occur on more than one island (Zimmerman 1957, Monserrat 1993).
Unlike the Galápagos endemics, the endemic Hawaiian chrysopid and hemerobiid species are well diff erentiated; they are generally distinguishable by large external diff erences in morphology, as well as distinct genital diff erences among males (there are no reports on the female genitalia).Also unlike the Galápagos endemics, the geographic origins and phylogenetic relationships of Anomalochrysa and the Hawaiian lineage of Micromus remain unknown.
In summary: On the Hawaiian Islands, each of the two families of lacewings is represented by a single, diverse endemic lineage of unknown origins; each of the lineages currently contains ~20 well diff erentiated species, the majority of which are confi ned to a single island.In comparison, the Galápagos has three endemic "lineages" of lacewings, each stemming from the separate introduction of a genus known to inhabit the South American mainland.Two of "lineages" currently consist of only one described species.Th e Chrysopodes (Neosuarius) lineage, consisting of three (perhaps four) species, also is small.In all three lineages, the degree of morphological diff erentiation is slight; diff erences between species are subtle, quite unlike the large interspecifi c variation within the endemic Hawaiian lineages.
Th ere are numerous possible causes for the marked contrasts in the extent of radiation and the degree of diversifi cation between the Hawaiian and Galápagos endemic lacewing lineages.Diff erences in the age, size, isolation, and ecological diversity of the island archipelagos may be factors; diff erences in the amount of time since the initial introductions, the especially harsh Galápagos environment and the biological characteristics of the original immigrant species are others to be considered.
Species relationships.Th e pattern of intraspecifi c and interspecifi c variation among the Galápagos lacewing specimens that we had on hand is noteworthy.In most cases, the diff erences among the species were consistent, and specimens could be easily and confi dently identifi ed to species.However, in one case, e.g., a male specimen in the series of C. (N.) nigripilosus from Pinta has particularly weakly pigmented wings and genitalia that resemble those of C. (N.) nigripilosus.As in some species of Darwin's fi nches on the Galápagos (Grant and Grant 2008), there may be a low incidence of hybridization between the Chrysopodes species.
Given the above, it is important to point out that in examining our C. (N.) nigripilosus and C. (N.) nigricubitus specimens carefully, we did not fi nd morphological diff erences that would warrant splitting the group further.Nevertheless, a pattern of diversifi cation and speciation without signifi cant morphological changes has been well documented within several chrysopid taxa -e.g., Chrysoperla, Chrysopa (Tauber and Tauber 1997, Tauber et al. 1995, Henry et al. 2001).Th us, it is possible that additional cryptic species remain within any of the nominal Chrysopodes species on the Galápagos.Th e unique morphological characteristics of the male abdomen and genitalia (i.e., the large eversible pouches at the terminus of the abdomen and the setose ducts within the gonarcus) are consistent with reproduction involving chemical signals -long-range or contact pheromones.It has been demonstrated that changes in the chemistry of such signals in insects can result in reproductive isolation, without noticeable changes in morphology (long-range pheromones, e.g., Roelofs and Rooney 2003; contact pheromones: e.g., Grula et al. 1980).We hope that future studies will examine the variation in pheromone chemistry and molecular characteristics among the Galápagos lacewings.
Conservation.During the bicentennial celebrations of Darwin's life and his contributions, many well-founded pleas have been made for the continued protection and study of the Galápagos Islands and their unique fl ora and fauna (e.g., J. E. McCosker & R. H. Rosenblatt, Darwin and the Galápagos Symposium, AAAS, Pacifi c Region, Aug. 14-15, 2009, California Academy of Sciences, San Francisco).Our fi ndings here, and the questions that they raise, add an additional, small but signifi cant reason for supporting these international and national conservation eff orts.
(N.) nigricubitus are cream-colored to light tan, without dark brown areas like those on the S5-S7 of C. (N.) nigripilosus and C. (N.) pecki females (Fig. 6).Although the C. (N.) nigricubitus genitalia resemble those of C. (N.) nigripilosus and C. (N.) peck, there are distinguishing features in the C. (N.) nigricubitus males.First, unlike C. (N.) nigripilosus and C. (N.) pecki, in which the lateral arms of gonarcus are directed downward next to the mediuncus, in C. (N.) nigricubitus the gonarcal arms are spread widely (Fig. 10c vs Figs 9c & 11c).Only the tips of the gonarcal arms bend downward, and the gonarcal structure is relatively fl at in lateral view.Second, in C. (N.) nigricubitus.the horizonal apodeme along the ventral margin of T9+ectoproct is relatively straight (lateral view), not arched as in C. (N.) nigripilosus.Th e tip of the caudal branch of the apodeme is pointed and without a fl ange; whereas in C. (N.
, for the ranges in head size and wing features.One male in the series from Pinta has particularly weakly pigmented wings and genitalia intermediate between C. (N.) nigripilosus and C. (N.) nigricubitus.Chrysopodes (Neosuarius) pecki sp.n. urn:lsid:zoobank.org:act:F2F8DB99-A134-433C-9FCB-317A86C40D77Diagnosis.Chrysopodes (Neosuarius) pecki, the third endemic species of Chrysopodes (Neosuarius) from the Galápagos, is known from two localities on Isabela Island -Volcán Wolf and Volcán Alcedo, where it is sympatric with C. (N.) nigripilosus.Although the number of specimens that are available is small (N=3) and they share many external and internal features with C. (N.) nigripilosus and C. (N.) nigricubitus, their distinctive size and other features lead us to assign them to a new species.Th e most prominent external features of C. (N.) pecki that are absent from the other two Galápagos species include: (a) a pair of brown spots on the dorsum of the head, posterolateral to the vertex (Fig. 3b) and (b) distinctive markings on the venter of the female abdomen (Fig. 6d).On the C. (N.) pecki females, S5 is dark brown, S6 has light brown pigmentation basally, and the distal portion of S6 and all of S7 are creamcolored.In comparison, C. (N.) nigripilosus females have dark brown pigmentation throughout S5, S6, and the base of S7, and C. (N.) nigricubitus females are without dark brown marks on the sternites.C. (N.) pecki is the only one of the three Galápagos species that has wings exceeding 13 mm in length.Like those of C. (N.) nigripilosus, the C. (N.) pecki wings do not show dark suff usion around the crossveins, but like C. (N.) nigricubitus, the second cubital crossvein is very dark and the center of the vein bears a dark brown swelling.In all three C. (N.) pecki specimens, the swelling tends to be smaller than that of C. (N.) nigricubitus (Table4, Fig.5c).

Table 1 .
Range of variation in head and thoracic features among geographic populations of two Chrysopodes (Neosuarius) species from the Galápagos Islands.

Table 2 .
Range of variation in head and thoracic features among three Chrysopodes (Neosuarius) species from the Galápagos Islands.

Table 3 .
Range of variation in wing characteristics among geographic populations of two Chrysopodes (Neosuarius) species from the Galápagos Islands.

Table 5 .
Range of variation in abdominal features among three Chrysopodes (Neosuarius) species from the Galápagos Islands.