Stenocyamops vittatus, Grimaldi, 2009

Grimaldi, David A., 2009, The Asteioinea of Fiji (Insecta: Diptera: Periscelididae, Asteiidae, Xenasteiidae), American Museum Novitates 3671, pp. 1-60 : 37-38

Stenocyamops vittatus , new species

Figures 3 , 21

DIAGNOSIS: Known only from females. Differs from other Stenocyamops specimens by bands of silvery microtomentum on cheeks that meet in center on face; thorax mostly ochre (including pleura, anepisternum brown), middle of scutum with longitudinal dark brown area that has diffuse lateral edges extending laterally beyond levels of dorsocentrals; abdominal tergites mostly dark brown, with the exception that all of tI and anterior portion of tII ochre.

DESCRIPTION: ThL 5 0.66 mm. Body coloration: Head: Frons, including fronto-orbital plates, ochre; area between ocelli dark brown. Postocciput, postgena yellowish; lower portion of face (at level of pseudovibrissae and lower), cheeks light brown, this brown area overlain with silvery microtomentum. Eyes pink with a greenish reflection. Antennal pedicel slightly darker than frons; basal flagellomere light brown, arista dark brown. Dorsal portion of scutum dark brown, edges diffuse and extended laterally slightly past level of dorsocentrals. Notopleural areas and most of pleura ochre; anepisternum, portion of anepimeron, and laterotergite light brown, anepisternum with silvery-reflective microtomentum. Wing hyaline, very slightly dusky with barely observable light transverse band in middle; haltere knob white; legs entirely light yellowish. Abdomen (female) with terminal tergites dark brown, graded to light yellowish on tergites I and II.

Head: Vertical setae lost in unique specimen, but judging from sockets they are well developed. Fronto-orbital setae well developed, located in middle of FO plate, separated by distance equal to diameter of socket; proclinate slightly shorter than reclinate. Pseudovibrissae well developed, projecting forward, separated by distance equal to diameter of socket; these subtended by pair of setae pointed laterad and upward, then by four pairs of setae on the cheeks pointed laterad and downwards; 2 long but finer setae on gena. Eyes without differentiation of facets, with fine, sparse interfacetal setulae. Antennal pedicel with deep dorsal cleft; mesal surface of pedicel longer than lateral surface; single strong seta on pedicel (on dorsomesal surface). Arista with long branches, length of longest branch ca. 0.5X length of arista, with 7 dorsal, 2 ventral branches (excluding terminal fork).

Thorax: Two pairs dorsocentrals (setae lost in HT), single row 10 long acrostichals; row of 5 long setae anterior to and in line with dorsocentrals. Three notopleural setae; 1 supraalar seta; 1 fine seta on postpronotal lobe, 1 long katepisternal seta, row of 4 fine setae on posterior margin of anepisternum. Single (apical) pair scutellar setae. Leg setation as described for Stenocyamops robustus . Male Terminalia: unknown. Female Terminalia: Tergite VI a narrow transverse strip, not connected to sternite, with pair of spiracles near lateral margins; tergite VII and sternite VII fused into ringlike syntergosternite, with pair of spiracles laterally; syntergosternite VII somewhat funnel shaped, with length of posterior margin 0.6X that of dorsal margin; two spermathecae, spherical, heavily sclerotized, lying at level of ventral margin of syntergosternite VII.

TYPES: Holotype, female (no. 33, dissected), FIJI: Vanua Levu, Bua Province , 6 km NW Kilaka, 15. VI –28. VI.04, Satiqere Range , Malaise. 146 m., Schlinger , Tokota’a , FJVN58 d_ MO1_07, 216.8153, 178.9854 FBA072145. Taveuni : Cakadrove Prov. , 5.6 km SE of Tavuki Village, Devo Peak , 1187 m, 30. VI –14. VIII.04, Malaise 1, Schlinger and Tokota’a, 16.843 ° E, 179.965 ° W, FBA150905 (female). In BPBM.

ETYMOLOGY: From the Latin, vitta, for (‘‘stripe’’), in reference to the dark median stripe running along the scutum.

KEY TO GENERA AND SPECIES OF FIJI PERISCELIDIDAE

1. Inner vertical setae absent; pair of reclinate frontal setae lying between proclinate frontoorbital setae; silvery microtomentum on anterior portion of fronto-orbital plates, on face and cheeks............ genus Cyamops , 2

– IV setae present (sometimes small); reclinate frontal setae posterior to proclinate setae; silvery microtomentum on cheeks or oral margin of face only, or missing......... 4

2. Femora brown, male with left surstylus broadly curved....... Cyamops femobrunneus , n. sp.

– Femora yellow or apically brown, left surstylus virtually straight.................... 3

3. Forefemur with ctenidium, left surstylus long........ Cyamops femoctenidius , n. sp.

– Forefemur without ctenidium, left surstylus short..... Cyamops fiji Baptista and Mathis

4. Larger bodied species with silvery microtomentum on cheeks and anepisternum, anepisternum with row of setae on posterior margin............ genus Stenocyamops , 5

– Smaller, slender species without silvery microtomentum on cheeks and anepisternum, anepisternum without setae ( Stenomicra )....... 8

5. Largest species, pleuron, venter of thorax and femora dark blackish brown......................... Stenocyamops robustus , n. sp.

– Smaller species, pleuron mostly yellow with dark anepisternum.................. 6

6. Mesoscutum with dark brown longitudinal stripe......... Stenocyamops vittatus , n. sp.

– Mesoscutum without brown stripe, entirely yellowish......................... 7

7. Male genitalia: surstylus scimitar shaped; hypandrium with fringed phragmata, pendulous lobes of cerci with apices pointed Stenocyamops ................... pseudoluteus , n. sp.

– Surstylus nearly straight, hypandrium without phragmata, pendulous lobes of cerci with round- ed apices.......... Stenocyamops luteus , n. sp.

8. Small, slender, grayish species with wings infuscate brown and three transverse bands.............. Stenomicra distinctipennis Collin

– Similarly colored or yellow or yellow-black species with entirely clear wings......... 9

10. Body entirely yellow or with light brown areas....... ( Stenomicra ariela complex) 11

– Body with yellow pleura and black-brown scutum and tergites...... S. distincta , n. sp.

11. Body entirely or virtually yellowish or whitish yellow.......................... 12

– Body with obvious light to dark brown infuscation on thorax............... 13

12. Body entirely light, surstylus (J) broad, scooplike......... Stenomicra ariela , n. sp.

– Thorax with very slight infuscation; surstylus slender, slightly S-shaped, with narrow apex........... Stenomicra pallida , n. sp.

13. Scutum brown, with yellow longitudinal stripe; pleura without brownish infuscation, all tergites brown........... Stenomicra brunnea , n. sp.

– Dorsal thorax light brown to very slightly infuscate, pleura with infuscation, anterior tergites brown.................... 14

14. Surstylus short, straight, with blunt apex.......... Stenomicra castanea , n. sp.

– Surstylus long, slender, curved, with pointed apex........................... 15

15. Each lobe of male cercus ventrally with large, stout seta........ Stenomicra sylpha , n. sp.

– Male cerci without such setae, or smaller ones........................... 16

16. Notum with slight bluish pruinescence, aedeagus fusiform with narrow tip......................... Stenomicra tokotaai , n. sp.

– Notum without pruinescence; aedeagus with trunk, apex broad and brushlike...................... Stenomicra xoutha , n. sp.

Figures

Fig. 3. Abdominal coloration of select Fiji Periscelididae, dorsal views (to same scale). A. Stenocyamops vittatus, n. sp. B. Stenocyamops robustus. C. Stenocyamops luteus, n. sp. D, E: Stenomicra tokotaii, male (D) and apex of female abdomen (E). F, G: Stenomicra distincta, male (F) and apex of female abdomen (G).

Fig. 21. Female terminalia of Fiji Stenocyamops, dorsal views (all to the same scale). A. S. luteus (spcm. 34). B. S. vittatus (spcm. 33). C. S. robustus (spcm. 31). Spermathecae are heavily sclerotized; the last pair of spiracles occur in the lateral margins of syntergosternite VII.