Sabethes (Sabethinus) andreae

Harbach, Ralph E., 2018, Two new species of the subgenus Sabethinus of Sabethes (Diptera: Culicidae) from Costa Rica, first confirmation of members of the subgenus in Central America, Zootaxa 4429 (2), pp. 269-280: 270-278

publication ID

https://doi.org/10.11646/zootaxa.4429.2.3

publication LSID

lsid:zoobank.org:pub:C2171F5B-8883-4030-A9C9-31460A0B1BF8

persistent identifier

http://treatment.plazi.org/id/3158E052-8A7C-FFA3-2EAB-FB5EFA1161AB

treatment provided by

Plazi

scientific name

Sabethes (Sabethinus) andreae
status

sp. n.

Sabethes (Sabethinus) andreae  , sp. n.

( Figs 1 – 3View FIGURE 1View FIGURE 2View FIGURE 3)

Adult, male and female. As described for the subgenus (Harbach, 1994). Similar in size and general appearance to other species of the subgenus; bearing the following distinctive and diagnostic features. Head: Vertex with iridescent violet scales; occiput with indistinct dull golden scales; proboscis with distal 0.2–0.3 flattened and gradually expanded laterally, more so in male than female, proboscis of female entirely dark-scaled, labella pale (yellow), proboscis of male with ventral patch of pale scaling 0.7–0.9 from base, scales yellow proximally grading into pure white distally. Thorax: Antepronotum with scales appearing bright iridescent azure blue in dorsal view, these noticeably different than iridescent violet scales of vertex; postgena with slightly golden to silvery-white scales. Legs: Predominantly dark-scaled, ventral surfaces of midtarsomeres 2 and 3, and usually part or all of tarsomere 4, with yellowish-white scaling; ventral surface of hindtarsomere 5, and sometimes distal part of hindtarsomere 4, white-scaled. Male genitalia ( Fig. 1 A–D View Figure ): Ninth tergal lobes not produced, each side of tergum with 2–4( 3) elongate, distally compressed and apically bent setae. Head of gonostylus without tergal process; lobe M without stem, broad and distally quadrate in lateral view, with a somewhat cylindrical lobe (?B) projecting more or less parallel to gonostylar stem from proximal area of mesal surface; lobe C a sharply recurved arm projecting toward gonostylar stem from near base of lobe M, free end with minute spicules on recurved side and acuminate apex.

Egg. Unknown.

Larva, fourth-instar ( Fig. 2 View Figure ). As described for the subgenus (Harbach, 1994); character and placement of setae as figured; resembles Sa. idiogenes  in having the stellate setae generally more highly branched than in other species of the subgenus; differing in the following primary differential and diagnostic features. Head: Seta 15-C more weakly developed than in Sa. intermedius  (particularly), Sa. idiogenes  and Sa. xhyphydes  , similar to 15-C of Sa. melanonymphe  but with fewer branches ( 5 or 6). Maxilla ( Fig. 3 View Figure ) with 3 prominent and 1 or 2 smaller teeth in lateral row; apical tooth distinctly longer than seta 4-Mx; seta 1-Mx peg-like, borne on tubercle as in the South American species but arising farther laterad on dorsal surface than usual, visible at side of maxilla in ventral view; seta 4-Mx relatively short and distinctly stout. Thorax: Seta 13-T double, very long, length 1.85–2.40 mm (mean = 2.13 mm). Abdomen: Seta 2-I strongly developed, stellate (distinction from Sa. xhyphydes  ); seta 9-I strongly developed, stellate (distinction from Sa. intermedius  , Sa. melanonymphe  , Sa. theresae  sp. n. and Sa. xhyphydes  ); seta 4-III,IV inserted ventromesad of seta 1 (unique, inserted anterior, anterolateral or lateral to seta 1 in Sa. idiogenes  , Sa. intermedius  , Sa. melanonymphe  and Sa. xhyphydes  ; mesad of seta 1 in Sa. theresae  sp. n.). Segment VIII: Comb similar to that of Sa. idiogenes  in having numerous spine-like scales (25–47, mean = 35). Siphon: Relatively short, length 1.20–1.40 mm (mean = 1.25 mm), width at mid-length 0.22–0.27 mm (mean = 0.25 mm), index 4.44–6.36 (mean = 5.09); basal sclerotisation pale, indistinct (unique); lateral surfaces without column of distinctly larger spicules extending from seta 1-S to apex (unique). Segment X: Seta 2-X with 4 or 5 branches, usually 5 (distinction from Sa. idiogenes  , Sa. intermedius  , Sa. melanonymphe  and Sa. xhyphydes  ); seta 3-X with 4 or 5 branches, usually 4 (unique); seta 4b-X with 2–5( 4) branches.

Pupa ( Fig. 3 View Figure ). As described for the subgenus (Harbach, 1994); character and positions of setae as figured; very similar to the other species of the subgenus. Abdomen: Seta 8-VII weakly developed, with 3–5( 3) branches (distinction from Sa. idiogenes  , Sa. intermedius  , Sa. melanonymphe  and Sa. xhyphydes  ). Paddle: Length 0.82–0.90 mm (mean = 0.86 mm), width at widest point 0.50–0.52 mm (mean = 0.51 mm), index 1.58–1.73 (mean = 1.68); apex rounded as in Sa. melanonymphe  and Sa. theresae  sp. n. (apex more triangulate in Sa. idiogenes  , Sa. intermedius  and Sa. xhyphydes  ).

Systematics. This is the most distinctive species of subgenus Sabethinus  described to date. Based on features of the male genitalia and the highly branched stellate setae of the larva, including the strongly developed seta 9-I, this species seems to be more closely related to Sa. idiogenes  than to the other species. However, it differs strikingly in other characters, including in particular the presence of pale scaling on the mid- and hindtarsi of adults, the position of seta 4-III,IV and development of the siphon of the larva, and the development of seta 8-VII of the pupa. Oddly, the pale scaling on the ventral surface of the midtarsus of adults is shared with species of the subgenus Sabethoides  , which until now has been considered to be a diagnostic character for that subgenus (Harbach, 1991).

Etymology. This species is dedicated to my beautiful daughter Andrea Lynn, who passed away unexpectedly at the youthful age of 34. As a young girl, Andrea was very much interested in “bugs” and was especially fond of “daddy legs”, i.e. daddy longlegs (order Opiliones: Arachnida).

Bionomics. Larvae of Sa. andreae  were found exclusively in the internodes of Merostachys latifolia R.W. Pohl.  Merostachys  is a Neotropical genus of bamboo in the grass family Poaceae  . Merostachys latifolia  have narrow stems (8 mm) and grow to heights of only 1.5–4.0 m. The collector mixed specimens from the same habitat according to locality, so it is not known whether Sa. andreae  was found in association with Sa. theresae  sp. n., which was found in the same type of bamboo. The small diameter of the bamboo is likely to severely limit the number of larvae that can inhabit a single internode. Larvae of Onirion regale Peyton & Harbach  and a species of Shannoniana Lane & Cerqueira  were also found in internodes of M. latifolia  (G. Chaverri, personal communication, 9 May 2003). Nothing is known about the bionomics of the adults of Sa. andreae  .

Distribution. Sabethes andreae  is only known only from the type locality near Golfito of Puntarenas Province in southern Costa Rica. As the type locality is near the border with Panama, the species is likely to occur in that country as well.

Type series. Seventy-five specimens (7 ♀, 11 ♂, 2 ♀G, 5 ♂G, 19 Le, 18 Pe and 13 L, including 14 individual larval rearings. Holotype ♂ (BHB-553.08), with Le + Pe and dissected genitalia on separate microscope slides: COSTA RICA: Prov. Puntarenas, Golfito, Jiménez, ACOSA, del Cerro Mueller, 0.2 km N. hacia Cerro Rincón, 680 m, 29 Jul 0 1, B. Hernández, [larva collected] En internudos de Merostachys latifolia  ( Poaceae  ), LS 273200 521500. Paratypes, with same data as holotype except as otherwise indicated: 6 ♀LePe (BHB-553.3–6, 9, 12; 3 and 12 with dissected genitalia on separate microscope slides); 6 ♂LePe (BHB-553.1, 2, 10, 11, 16, 17; 16 and 17 with dissected genitalia mounted on microscope slide with LePe), 8 L (BHB-553a, 553b, 553c,d,e, 553f,g,h; a and b with dissected maxillae), 2 Le + 2 Pe on same microscope slide (BHB-553.4b); P.N. Corcovado, 0.4 km N. del Cerro Rincón, 28 Jul 0 1, 1 ♀LePe + 1 Le (BHB-547.2), 2 ♂LePe (BHB-547.1, 3; 3 with dissected genitalia on separate microscope slide), 3 L (BHB-547a,b,c); P.N. Corcovado, 2.8 km N. del Cerro Mueller, 28 Jul 0 1, 2 ♂ (BHB-548.4, 4 b; 4 with dissected genitalia on microscope slide), 2 L (BHB-548c, 548d; c with dissected maxillae). Additional specimens: 16 ♀, 13 ♂ (BHB-553); 3 ♀, 2 ♂ (BHB-548). The type series and additional specimens are deposited in the Museo Nacional de Costa Rica (MNCR), Cuesta de Moras, San José, Costa Rica.

Sabethes (Sabethinus) theresae  , sp. n.

( Figs 1 View Figure , 4 View Figure , 5 View Figure )

Adult, male and female. As described for the subgenus (Harbach, 1994). Similar but somewhat darker than Sa. andreae  sp. n. Head: Vertex with iridescent violet scales as in Sa. andreae  sp. n.; postgena with golden to silvery scales at side of head; proboscis of male with ventral patch of white scales 0.60–0.85 from base. Thorax: Antepronotum with scales appearing iridescent golden in dorsal view, these noticeably different than iridescent violet scales of vertex. Legs: More extensively dark-scaled than legs of Sa. andreae  sp. n., ventral surfaces of tarsomere 5 of fore- and hindlegs white-scaled, midtarsomeres 2 and 3 with indistinct ventral pale scaling. Male genitalia ( Fig. 1 A–D View Figure ): Ninth tergal lobes slightly produced, separated by very narrow bridge, each with 2 relatively short curved setae that are slightly if at all flattened distally. Head of gonostylus with smaller lobes than in Sa. andreae  sp. n.; tergal process also absent; lobe M slender and stem-like, lobe?B absent; lobe C uniquely developed among known species of the subgenus, not recurved, developed as a narrow club-like process arising from the basal sternolateral margin of lobe M and projecting more or less parallel to that lobe, free end slightly enlarged and minutely spiculate.

Egg. Unknown.

Larva, fourth-instar ( Fig. 4 View Figure ). As described for the subgenus (Harbach, 1994); character and placement of setae as figured; differing from other species of the subgenus in the following primary differential and diagnostic features. Head: Seta 15-C developed as in Sa. andreae  sp. n. weakly developed compared to 15-C of Sa. intermedius  , Sa. idiogenes  and Sa. xhyphydes  , similar to 15-C of Sa. melanonymphe  but with generally fewer branches ( 3 –7). Maxilla ( Fig. 5 View Figure ) similar to the maxilla of Sa. idiogenes  in having the first lateral tooth displaced dorsally and not in line with the other lateral teeth, but differs in not being widely separated from the second lateral tooth; apical tooth slightly if at all longer than seta 4-Mx; seta 1-Mx slender, not peg-like and not borne on a tubercle (unique); seta 4-Mx relatively short and stout, about as long as apical tooth. Thorax: Seta 13-T single, stout and tapered, length 0.90–1.05 mm (mean = 0.98 mm). Abdomen: Seta 2-I strongly developed, stellate (distinction from Sa. xhyphydes  ); seta 9-I weakly developed compared to 9-II–VII, with 2 or 3 branches, usually 3 (distinction from Sa. andreae  sp. n. and Sa. idiogenes  ); seta 4-III,IV inserted mesad of seta 1 (unique, inserted anterior, anterolateral or lateral to seta 1 in Sa. idiogenes  , Sa. intermedius  , Sa. melanonymphe  and Sa. xhyphydes  ; ventromesad in Sa. theresae  sp. n.). Segment VIII: Comb with 14–22 spine-like scales (mean = 18). Siphon: Relatively long, length 1.25–1.50 mm (mean = 1.39 mm), width at mid-length 0.15–0.20 mm (mean = 0.17 mm), index 6.50–9.38 (mean = 8.16); basal sclerotisation darkly pigmented, distinct; lateral surfaces with column of distinctly larger spicules extending from seta 1-S to apex (distinction from Sa. andreae  sp. n.). Segment X: Seta 2- X with 3 or 4 branches; seta 3-X with 2 branches (distinction from Sa. andreae  sp. n. and Sa. xhyphydes  ); seta 4b- X with 3–7( 4) branches.

Pupa ( Fig. 5 View Figure ). As described for the subgenus (Harbach, 1994); character and positions of setae as figured; very similar to the other species of the subgenus. Abdomen: Seta 8-VII weakly developed (distinction from Sa. idiogenes  , Sa. intermedius  , Sa. melanonymphe  and Sa. xhyphydes  ), single or double, more often single (distinction from Sa. andreae  sp. n.). Paddle: Length 0.69–0.80 mm (mean = 0.74 mm), width at widest point 0.33–0.40 mm (mean = 0.38 mm), index 1.82–2.42 (mean = 1.95); apex rounded as in Sa. melanonymphe  and Sa. andreae  sp. n. (apex more triangulate in Sa. idiogenes  , Sa. intermedius  and Sa. xhyphydes  ).

Systematics. Based on the presence of pale scaling on the legs of adults, the absence of a tergal process on the gonostylus of males and the weakly developed seta 8-VII of pupae, Sa. theresae  sp. n. appears to be more closely related to Sa. andreae  sp. n. than to the four South American species. The true affinities of the species may not be known until other species of the subgenus have been discovered and described (see Discussion below) and subjected to phylogenetic analyses that include a combination of morphological and molecular data.

Etymology. This species is dedicated to my retired friend and colleague Theresa M. Howard, who skilfully produced many mosquito illustrations, including those in the present paper, and co-authored a number of taxonomic papers with me while we worked together in the Natural History Museum.

Bionomics. Larvae of Sa. theresae  sp. n. were found exclusively in the internodes of Merostachys latifolia R.W. Pohl. As  indicated for Sa. andreae  sp. n., M. latifolia  have narrow stems (8 mm) and grow to heights of only 1.5–4.0 m. The collector mixed specimens from the same habitat according to locality, so it is not known whether Sa. theresae  sp. n. and Sa. andreae  sp. n. were found together in a single internode (doubtful), in different internodes of the same plant or in the internodes of different plants. Larvae of Onirion regale  and a species of Shannoniana  were also found in internodes of M. latifolia  (G. Chaverri, personal communication, 9 May 2003). Nothing is known about the bionomics of the adults of Sa. theresae  sp. n.

Distribution. Sabethes theresae  is only known only from the type locality near Golfito of Puntarenas Province in southern Costa Rica. As the type locality is near the border with Panama, the species is likely to occur in that country as well.

Material examined. Thirty-seven specimens ( 2 ♀, 5 ♂, 2 ♀G, 4 ♂G, 7 Le, 10 Pe and 7 L, including seven individual larval rearings. Holotype ♂ (BHB-548.13), with Le + Pe and dissected genitalia on separate microscope slides: COSTA RICA: Prov. Puntarenas, Golfito, Jiménez, ACOSA, P.N. Corcovado, 2.8 km N. del Cerro Mueller, 680 m, 28 Jul 0 1, B. Hernández, [larva collected] En internudos de Merostachys latifolia  ( Poaceae  ), LS 273200 521500. Paratypes, with same data as holotype: 2 ♀LePe (BHB-548.3, 12; both with dissected genitalia on separate microscope slides); 5 ♂LePe (BHB-548.7, 9, 10, 11, 13; 7 with dissect genitalia on microscope slide with LePe; 9, 10 and 11 with dissected genitalia on separate microscope slides), 7 L (BHB-548a, 548b, 548c,d, 548e,f,g, 548h,i,j; a with dissected maxillae). Additional specimens: 3 ♀, 5 ♂ (BHB-548). The type series and additional specimens are deposited in the Museo Nacional de Costa Rica (MNCR), Cuesta de Moras, San José, Costa Rica.

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Diptera

Family

Culicidae

Genus

Sabethes