Revision of the Griburius scutellaris (Fabricius, 1801) species group (Coleoptera: Chrysomelidae: Cryptocephalinae) Author Sassi, Davide text Zootaxa 2023 2023-07-13 5315 6 501 548 http://dx.doi.org/10.11646/zootaxa.5315.6.1 journal article 10.11646/zootaxa.5315.6.1 1175-5326 8142503 33189294-DC74-4CFA-8213-2600B8459040 Griburius decoratus ( Suffrian, 1852 ) stat. restored ( Figs 1c ; 5 ; 12d ) Scolochrus decoratus Suffrian 1852: 124 (original description); Suffrian, 1858: 392 (taxonomic notes); Jacoby 1880: 61 (taxonomic notes); Jacoby 1889: 126 (taxonomic notes). Griburius decoratus : Clavareau, 1913: 90 (as syn of G. larvatus , catalogue); Blackwelder, 1946: 640 (as syn. of G. larvatus , catalogue); Niño-Maldonado et al. , 2014: 127 (catalogue). The only critical discussion on the status of G. decoratus subsequent to its description ( Suffrian, 1866 ) is that of Jacoby (1880) who considers the taxon conspecific of G. larvatus , but he strangely uses the epithet decoratus as prevailing on the older larvatus . The synonymy appears without further comments in the subsequent catalogues ( Clavareau, 1913 and Blackwelder, 1946 ) but with the acknowledgement of the priority of the epithet larvatus . In the collections studied by me (for instance BMNH and MNHUB) the two species appear mixed up and in any case with confused determination, and the epithets larvatus , decoratus and spadiceus used in a very imprecise way. Even though the epithet decoratus appears in a recent work ( Niño-Maldonado et al. , 2014 ) correctly referring to the taxon present in Mexico but without any comments or critical discussion, it is considered useful to formally confirm the species status of G. decoratus as a distinct species from G. larvatus . FIGURE 5. G. decoratus . a–b: habitus, dorsal and lateral view (LT); c: frontal view, female; d: frontal view, male (Catemaco, Mexico); e–f: colour variations (e: male, Catemaco, Mexico; f: female, El Salto de Eyipantla, Mexico); g–k: median lobe of aedeagus in ventral (g), dorsal (h) and lateral (k) view [0.5 mm]; m: antenna [1.1 mm]; n: spermatheca [0.4 mm]. hd: setose depressions. Square brackets: length of scale segment. Scolochrus spadiceus Suffrian, 1852: 131 (original description); Suffrian, 1858: 392 (taxonomic notes). Scolochrus decoratus spadiceus : Jacoby 1880: 61 (as subsp. of G. decoratus , taxonomic notes). Griburius spadiceus : Clavareau, 1913: 90 (as syn. of G. larvatus , catalogue); Blackwelder, 1946: 640 (as syn. of G. larvatus , catalogue). Syn. nov. Griburius spadiceus was given the status of “variety” by Jacoby (1880) , so, strictly speaking, it should have been considered at a subspecific level, but in the following brief discussion, Jacoby seemed to give no weight to this chromatic form. Confirming this, there is the fact that the taxon was no longer mentioned in the supplementum ( Jacoby, 1889 ). However, given the present confusion in the literature among the three epithets larvatus , decoratus and spadiceus , a formal statement of new synonymy is given here to clearly establish the status as a full synonym of G. decoratus . Types. Suffrian did not mention the number of the specimens of Griburius decoratus available for the study, but he gave a long and detailed description of the colour pattern variability and pointed out some features for both males and females, therefore he was able to study a quite high number of specimens. To confirm this, he gave an unusual long (10 items) list of private and public collections as depositories of the available material. He pointed out seven “variants” on the basis of the elytral colour pattern, but he clearly did not give this variation any taxonomic significance because none of those “variants” were given a name, and no described chromatic pattern was linked to a geographic datum. On the other hand, he was convinced he was describing a Mexican species, as he wrote: “From Mexico ( Oaxaca ) and probably widespread there and not rare, since it is present as the most common species in almost all the collections that I have compared”. The inspection of the collections available at present, allowed to trace down four syntypes in MNHUB (two from Mexico and two from Texas , which is not mentioned in the original description) and three syntypes in BNHM (all of them from Mexico ). Unexpectedly, the two specimens from Texas in MNHUB turned out to belong to a different species with respect to the reminders. Since Suffrian stated that his species was a Mexican species, as mentioned above, the name-bearing specimen was chosen accordingly. Consequently, the Texan specimens turned out to belong to a new taxon which is described below ( Griburius rileyi n. sp. ). It might be objected that, being the locality not mentioned in the description, the specimens should be excluded from the type series. This would be a sensible point, but it should be noticed, on the other hand, that the catalogue number (23993) makes them fully embedded in a long list of material unquestionably seen by Suffrian and used as the basis for the description of several taxa. Moreover, it has already been pointed out ( Sassi, 2018 ) that Suffrian was sometimes not very precise in reporting all the data on the attached labels. Taking all these circumstances into account, the Texan specimens were considered part of the type series. In order to stabilize the epithet, the typification was made as follows. LECTOTYPE (by present designation): ♀ , pinned, // “23995” [white label, printed] // “decoratus var Suffr.” [blue label, handwritten] // “ Griburius decoratus ( Suffrian, 1852 ) ( Scolochrus decoratus ) LECTOTYPUS D. Sassi des.” [red label, printed] // (MNHUB). The label information for this specimen matches the registration data from the old catalogue of the MNHUB (“23995 [ Scolochrus decoratus ] var. 1. [ Mexico ]”). PARALECTOTYPES were designated as follows. 1♀ , pinned, // “23994” [white label, printed] // “ Scolochrus decoratus var Suffr. Mexico Saubert” [blue label, handwritten] // (MNHUB); 1♁ 1♀ , pinned // “23993” [white label, printed] // “ Scolochrus decoratus Suffr. ” [blue label, handwritten] // “10maculatus Reiche Texas Buguet” [white label, handwritten] // “ Scolochrus decoratus var Suffr. Mexico Saubert” [blue label, handwritten] // “ Griburius rileyi sp. nov. PARATYPUS D. Sassi des.” [red label, printed] // (MNHUB); 1♀ , pinned, // “ Scolochrus decoratus Suffr Mexico ” [white label, handwritten] // “Named by Suffrian” [white label, handwritten] // “Baly Coll.” [white label, printed] // “Type. Sp. figured.” [white label, printed] // (BMNH); 1♀ , pinned, // “ Scolochrus decoratus Suffr Mexico ” [white label, handwritten] // “Named by Suffrian” [White label, handwritten] // “Baly Coll.” [white label, printed] // “Type. Sp. figured.” [white label, printed] // (BMNH); 2♀ , pinned, // “Type Suffrian Coll Deyrolle” [white label, handwritten] // “Baly Coll.” [white label, printed] // (BMNH). The label information for the MNHUB paralectotypes matches the registration data from the old catalogue of the MNHUB. All paralectotypes were labelled: // “ Griburius decoratus ( Suffrian, 1852 ) ( Scolochrus decoratus ) PARALECTOTYPUS D. Sassi des.” [red label, printed] //. Regarding Griburius spadiceus , a female specimen housed in MNHUB matches the information in the original description and can be considered as belonging to the type series. In order to stabilize the epithet, the typification was made as follows. LECTOTYPE (by present designation): ♀ , pinned, // “23996” [white label, printed] // “ Scolochrus spadiceus Suffr Mosquito Mull” [blue label, handwritten] // “ Griburius spadiceus ( Suffrian, 1852 ) ( Scolochrus spadiceus ) LECTOTYPUS D. Sassi des.” [red label, printed] // “ Griburius decoratus ( Suffrian, 1852 ) D. Sassi det. 2015” [white label, printed] // (MNHUB). The label information for this specimen matches the registration data from the old catalogue of the MNHUB (“23996 – spadiceus Suffr. * 1. Mosquito, Mull.”). Type locality. G. decoratus : “ Mexico ”. G. spadiceus : “ Mosquito Coast ” (Honduras-Nicaragua). Additional material examined . BELIZE : Cayo : Blancaneaux Lodge Chiquebul Road at Privassion Creek 7.VII.1981 (1, USNMNH ) ; Stann Creek : Stann Creek Valley Melinda V–VI.1976 (1, TAMU ) ; Toledo : 2 mi SW Punta Gorda 16.VIII.1978 (1, BMNH ) ; Ruinas Lubaantun 6.VIII.1988 ( ERPC ) . GUATEMALA : Alta Vera Paz : Lanquin 2–5.VI.1948 (5, FIMU ) ; Panzós (1, USNMNH ). HONDURAS : Atlantida : Playas de Peru 28.V.1993 (1, FSCA ) ; Cortés : Villanueva Bufalo 11.VIII.2022 (1, GBIF ) . MEXICO : “ Mexico ” (18, MNHUB & ZMUC & HNHMB & NHMP & MSNG & USMNHN ); “Mexico” coll. Kraatz & coll. Haag (4, SDEI ); “Mexico Müller” (3, SDEI ). CAMPECHE : Chicanna Ruins 6 mi W Xpujil 27.VII.1980 ’ (1, TAMU ) . CHIAPAS : 8.4 mi N Ocozocoautla 2900 ft 16.VIII.1967 (5, TAMU ) ; 4 mi NE Pichucalco 14.VI.1965 (1, TAMU ) ; 2 mi N Tapilula 16.VI.1965 (3, TAMU ) ; 31 km E La Trinitaria 4800 ft 14.VIII.1967 (1, TAMU ) ; Palenque 22.VI.2011 (1, MSPC ) ; Ruins at Palenque 26.VI.1959 (2, AMNH ) ; 2.4 km NNW Ojo de Agua 7.VI.2011 ( DSPC ) ; 18 km N Ocosinga 24.VI.1987 (1, TAMU ) ; Simojovel VI.1989 & 10.VII.1990 & 8.VI.1991 (9, ERPC ) . HIDALGO : 3 mi W Hidl. & S.L.P. border on 85 25.V.1979 ( 1 ( ERPC ); Chapulhuacan 20.V.1952 (3, AMNH ) . JALISCO : 28 mi E Guadalajara 15.VIII.1962 (3, CNCI ) . NUEVO LEON : Linares 1.VII.1973 taken at light (1, TAMU ); 27 km W Linares 22.VIII.1977 light (1, TAMU ); 15 mi W Linares 2.VII.1973 (1, TAMU ) . OAXACA : “ Oaxaca ” (2, CNCI & USNMHN ); Mathias Romero 12.VII.1992 (1, NHMB ) ; Mathias Romero 10.VII.1957 (1, CNCI ) ; Chiltepec 17.VIII.1998 (11, MSPC ) ; Temascal 30.VI.1964 (2, BYU ) ; Valle Nacional 11.VIII.1989 ( ERPC ) . PUEBLA : Pozo Tlaxcalaltongo 12.VII.1970 (2, CNIABM ) ; Necaxa [uncertain because difficult to decipher] (1, USNMNH ). QUINTANA ROO : 10 mi N Chetumal 18.V.1985 (2, ERPC ) ; Cancun 10.VIII.1990 (3, ERPC ) ; 1–5 km S Cancun at light 3.VI.2009 (1, BYU ) ; Nuevo Xcan 6.VI.1959 (1, AMNH ) ; Chetumal-Caldevitas 6.VI.1994 (2, MDPC & NHMP ) . SAN LUIS POTOSÍ : Tamazunchale 18–22.VI.1941 (6, FIMU ) ; 35 mi N Tamazunchale 30.VII.1960 (2, CNCI ) ; 8 mi N Tamazunchale 700’ 24.VII.1882 ( ERPC ) ; Huichihuayan 20 mi N Tamazunchale 19.V.1952 (1, AMNH ) ; Huichihuayan 8.VIII.1967 (1, TAMU ) ; Xilitla 1800’ 24.VII.1954 (1, CNCI ) ; 2 mi E Xilitla 22.VI.1970 (2, TAMU ) ; 3.4 mi W Xilitla 23.VIII.1974 (1, TAMU ) ; 4 mi NE Xilitla 2500’ 26.V.1974 (2, ERPC ) ; 5 mi NE Ciudad del Maiz 4500 ft 22.VIII.1954 (1, CNCI ) ; Valles 26.VI.1940 & 18.V.1952 (5, FIMU & AMNH ) ; 17 mi N Valles 7.VII.1966 (1, TAMU ) ; 20 mi W Valles 2.VIII.1971 (1, BYU ) ; Axtla 23.VI.1941 (1, FIMU ) ; El Salto Falls 2000–2500 ft 8.VIII.1963 (1, FSCA ) ; El Salto Falls 25.V.1979 (1, ERPC ) ; El Salto 5.VI.1965 (3, TAMU ) ; El Salto de Agua 28.VII.1960 (1, CNCI ) ; 1 mi E El Naranjo 7.VIII.1967 (1, TAMU ) ; 6 mi S Matalpa 7.VII.1966 (1, TAMU ) ; Picolco 21.V.1952 (2, AMNH ) . TABASCO : La Cantalpa 30.IV.1973 (1, USNMNH ) ; 30 mi W Cardenas 4.VII.1971 (7, TAMU ) ; Campo Exp. CSAT 20 km W Cardenas 23.VII.1980 (2, TAMU ) ; Teapa 29.VI.1964 (2, AMNH ) . TAMAULIPAS : Bocatoma 7 km SSE Gomez Farias 19.V.1979 & 4.VI.1982 (15, FSCA & TAMU & ERPC ) ; Ets. Biol. Los Cedros Gomes Farias 350 m 26.VII.1993 (1, TAMU ) ; 5 mi N Llera 4.VI.1965 (1, TAMU ) ; 6 mi N Manuel 25.VIII.1974 (1, TAMU ) ; 18.6 mi S Tampico 13.VIII.1972 (1, TAMU ) ; Antiguo Morelos 1400ft 20.VII.1954 (1, CNCI ) . VERACRUZ : Veracruz (5, TAMU & NHMP & AMNH ); Veracruz 3.VII.1941 (3, FIMU ) ; Veracruz VIII.1959 & VII.1965 (7, USNMHN ) ; 26 mi E Huatusco 29.VI.1991 (2, FSCA ) ; Fortin 30.V.1986 (1, FSCA ) ; Fortin 25.VII.1956 (1, AMNH ) ; Catemaco 22.VIII.1967 (1, TAMU ) ; 1.6 mi S Catemaco 8.VI.1965 (1, TAMU ) ; 16.5 mi S Catemaco 17.VI.1985 (12, FSCA ) ; 2–7 mi S Catemaco 31.VIII.1980 (2, BYU ) ; Lake Catemaco 3.VII.1959 & 4.VI.1963 (3, AMNH & FSCA ) ; Playa Azul Lake Catemaco 7.VII.1957 (2, FIMU ) ; env. El Salto de Eyipantla 15 kn S San Andres Tuxtla 15.VI.1985 (19, FSCA ) ; San Andres de Tuxtla 15.VII.1966 (1, TAMU ) ; 2.8 mi SE Tebanca E of Catemaco 17.VI.1985 (1, FSCA ) ; 1.5 mi NE Tatahuicapan 25.VI.1985 (4, FSCA ) ; Cerro Gordo ca 3000 ft alt 3.VII.1941 (5, FIMU ) ; Puente Nacional 3.VII.1941 (1, FIMU ) ; 9.5 mi NE El Tropico 26.VI.1985 : Mendoza 1300m 22.VII.1983 (1, MNHUB ) ; Los Mongos 9.VII.1974 (1, TAMU ) ; Mpio Puente nacional El Crucero nr Puente nacional 13.VI.1997 (1, TAMU ) ; Puente nacional 17.VII.1960 (1, CNCI ) ; 12 mi NW Amate 1.VII.1971 (2, TAMU ) ; 3 mi N Huatusco 29.VI.1971 (1, TAMU ) ; 14 mi W Conejos 30.VI.1971 (5, TAMU ) ; 5 km W Conejos 30.VI.1971 (1, TAMU ) ; 4 mi NE Minatitlan 11.VI.1965 (3, TAMU ) ; Lerdo de Tejada 29.VIII.1962 (1, TAMU ) ; 7 mi NE Mata Espino 1.VII.1971 (3, TAMU ) ; 3 mi W Cardena 4.VII.1971 (2, TAMU ) ; 20 mi SE Jalapa 30.VIII.1980 (1, BYU ) ; 6 mi SW Coatzacoalcos 21.VII.1967 (1, TAMU ) ; 5 mi W Palma Sola 28.VII.1974 (2, TAMU ) ; Tierra Blanca 28.VII.1941 (1, CNCI ) ; 17 mi N Acayucan 11.VI.1965 (1, TAMU ) ; San Juan de la Punta 18.VII.1941 (2, FIMU ) ; Córdoba 11.VII.1936 (1, FIMU ) ; Cordova [sic.] [Córdoba] (1, SDEI ); Hueyapan 8.VII.1957 ( FIMU ) ; Tamascal 19.VII.1980 (2, TAMU ) ; Tolome nr Rinconada 27.VII.1955 (2, AMNH ) ; Rinconada 2000 ft alt. 29.VI.1941 ( FIMU ) ; El Tajin Ruins 10 mi S Poza Rica (2, FSCA ); Vega de Alatorre 28.VI.1971 (1, TAMU ) ; 5 mi NW Lerdo de Tejada 10.VI.1965 (1, TAMU ) ; 2 mi E Tula 10.VI.1965 (1, TAMU ) ; Atoyac 25.VI.1982 (4, BYU ) ; Plan del Rio 2500 ft alt. 6.VII.1957 (1, FIMU ) ; Orizaba (1, NHMP ); Xalapa (2, FIMU ); Hwy 150 2 mi E Cuitlahuac 3.VIII.1965 (9, ERPC ) ; Tierra Blanca (1, AMNH ). YUCATÁN : Piste 8.VI.1959 (2, AMNH ) ; Piste 8.VI.1959 (2, AMNH ) ; 17 km N Piste 16.VI.1990 (1, TAMU ) ; 10 kn S Piste 14.VI.1991 UV light (1, FSCA ); Chuminopolis 12 VII.1952 & 4.VIII.1952 & 6.VIII.1964 (5, AMNH ) ; Tixkokob (1, 5.VII.1952 (1, AMNH ) ; Tixkokob 5.VII.1952 (1, AMNH ) ; Dolores Otero 13.VII.1952 (2, AMNH ) ; Cordeleira Mayapan 29.VI – 2.VII.1952 (5, AMNH ) ; Cordeleira Mayapan 3.VIII.1952 (1, AMNH ) ; Acanceh 31.VII.1952 (1, AMNH ); Temax (6, SDEI ) ; Chitzin Itza 13.VI.1993 (1, TAMU ) ; Chichen Itza 20.VII.1952 (1, AMNH ) ; Chichen Itza 18.V.1987 (1, ERPC ) ; Chichen Itza (2, FIMU ) ; 6–10 km W Valladolid 2.VIII.1990 (2, BYU ) ; Merida 29.VII.1964 (2, USNMNH ) . Additional data from literature . Tamaulipas ( Niño-Maldonado et al. , 2014 ). The ambiguous type locality of G. spadiceus could indicate its presence in Nicaragua , but this country record remains unconfirmed . Distribution. Belize , Guatemala , Honduras , Nicaragua ?, Mexico (new to Belize , Guatemala ). Diagnosis . Very similar to G. rileyi and G. larvatus , this species is distinguished from both by the greater extension of the dorsal black pattern. In particular, the two spots on the disc of the pronotum tend to be angular, and almost always touch the anterior margin and, sometimes, also the posterior one. The tendency of the elytral spots to fuse is more developed than in the two species mentioned above, and therefore the pattern with two dark transverse bands, one basal and one postmedian, is very common. The examination of the aedeagal median lobe allows a more reliable identification: in ventral view, in G. decoratus the apex is shorter, its sides forming almost right angles with the profile of the aedeagal tube. In G. rileyi and G. larvatus the sides of the apex form a much more open angle. Description of male. BL = 3.9–4.8 mm , BW = 2.4–3.0 mm, PL = 1.4–1.9 mm , PW = 2.3–2.8 mm . Interocular distance 2.6–4.2 % of BL. Head ( Fig. 5d ) yellow with vertex, surface between upper lobes of eyes and insertion of antennae black. Labrum yellow. Vertex matt, sparsely and shallowly punctured with very short, recumbent, whitish setae. Surface of frontoclypeal area matt as well, with sparse, weakly impressed punctation and scattered setae. Longer setae only between antennal insertions. Mid-cranial suture well detectable on lower part of vertex and between upper lobes of eyes. Upper lobes of eyes close to each other along midline, but always separated by distinct strip of frons space. Ocular lines narrow, marked by row of punctures, strictly adhering to ocular rim up to ocular canthus. Ocular canthus large not differentiated in punctation and setosity from the remainder of frontoclypeal surface. Antennae ( Fig. 5m ) with antennomeres 1–2 yellow, 3–11 progressively darkened; antennomeres 3–5 bright, subcylindrical; antennomeres 6–11, dull, more flattened and more diffusedly setose. Pronotum yellow with two large, angulate black spots extended from anterior margin up to posterior half of disc. Sometimes such spots reaching posterior margin. Pronotal shape roughly elliptical, moderately transverse, perceptibly flattened on disc. Lateral margins narrow, not visible from above, regularly curved so that maximum width nearly at middle. Surface moderately shiny with scattered, fine punctation at middle of disc. Punctures coarser and more deeply impressed along sides and in proximity of posterolateral impressions. Posterolateral impressions well distinguishable and obliquely arranged, marked by some strong punctures at bottom of depression. Pronotal posterior margin thickened along posterolateral impressions. Scutellum yellow, sometimes vaguely tinged with brownish at center, subtriangular with apex shortly truncated. Surface minutely and sparsely punctured, with scarce, very short setae. Elytron usually yellow with large subrectangular black band along basal margin, occupying whole anterior fourth, leaving free only postscutellar area. Second transverse, slightly sinuous black band extended between midline and apical clivus. Further black spot, rising from latter, extended along suture, broadened onward and generally meeting the anterior black band. Suture along apical clivus narrowly black. Quite frequently black design less developed, with transversal bands fractioned into separate, roughly rounded spots, giving 4 + 1 + 3 pattern on total area of two elytra. More rarely, part of those spots missing or very small. Epipleuron yellow. Elytral outline short with sides almost straight and convergent posteriorly. Lateral margins narrow, simultaneously visible from above only along posterior half. Elytral surface slightly flattened on disc, moderately shiny with well-impressed punctation arranged in almost regular rows, distinct up to posterior clivus. Intervals flat. Postscutellar area fairly raised. Humeral callus prominent, impunctate. Epipleuron smooth, impunctate, with convex surface. Pygidium totally yellow. Surface matt, covered with close shallow punctures and appressed, pale setae. Ventral parts of thorax black usually with yellow spot on metasternum. Prosternal process spotted with yellow as well. Abdominal ventrites 1–4 black with yellow margins. Fifth abdominal ventrite almost completely yellow. Hypomera, mesepimera and mesepisterna almost bare, shiny, with scattered punctures. Remainder of ventral surface of thorax matt, covered with rather dense, short, regularly distributed setae and fine, shallow punctures. Prosternal process large, with sides almost straight between anterior coxae, then converging in large, round apex; surface anteriorly almost flat, then slightly concave toward apex, covered with coarse, shallow punctures and sparse, long, semi-erect setae. Legs totally light yellow. Median depression on fifth abdominal ventrite very shallow and hardly detectable, but with fewer setae and punctures than remainder of ventrite surface.Ventrite posterior margin very feebly notched. Median lobe of aedeagus ( Fig. 5g –k ) with apex bluntly terminated in almost straight line, with median short, acute denticle. Ventral outline marked with low, straight carina along nearly whole aedeagal shaft. Setose depressions narrow, shallow laterally, with surface covered by small punctures and long arcuate setae. Female . Habitus in Fig. 5a–b (LT). BL = 5.0– 5.8 mm , BW = 3.3–3.8 mm , PL = 1.8–2.2 mm , PW = 2.9–3.4 mm . Interocular distance 10.3–12.0 % of BL. In females, the eyes ( Fig. 5c ) are smaller and more separated along midline, and the punctation on head is more robust and denser on vertex and between eyes, sparser and shallower on clypeal area. The colour pattern is generally like that of males, but at times dorsal black markings are smaller. In the lightest specimens, the elytron is yellow with small, rounded spots on humeral callus, just beside the scutellum and on disc just behind the midline. In these specimens the lateral margin and the suture are narrowly black as well. The fifth abdominal ventrite in females has a large, rounded and deep pit. The bottom of the pit is black (while the remainder of the ventrite is yellow), glabrous, matt, impunctate but covered by tiny wrinkles. The vasculum of the spermatheca ( Fig. 5n ) is scarcely pigmented, sickle-shaped with slightly swollen proximal lobe. The distal lobe is long, slender, tapered with a rather acute apex mildly bent downwards. The ampulla is not pigmented, short. The duct insertion on the ampulla is short, slender and not pigmented. The sperm gland insertion is longer and bent upwards. The duct is uniform in size, slender, quite rigid, not coiled but with a series of turns forming a small tangle at some distance from the vasculum, then almost straight. The insertion on the bursa copulatrix is simple, neither swollen nor pigmented. Remarks . The “form” spadiceus is relatively common in the Yucatán Peninsula (in the states of Yucatán and Quintana Roo ) but not confined to that region. However, apart from the lighter shade of the dorsal colour (chestnut instead of black), there is little morphological support to give this “variant” a taxonomically valid rank. The synonymy with G. decoratus is therefore confirmed.