(RAGONOT) (PYRALIDAE: PHYCITINAE)L
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, \ VOLUME 30, NUMBER 2 133 \ DESCRIPTIONS OF THE IMMATURE STAGES AND BIOLOGY OF VITULA LUGUBRELLA (RAGONOT) (PYRALIDAE: PHYCITINAE)l H. H. NEUNZIG Department of Entomology, North Carolina State University, Raleigh, North Carolina 27607 Vitula lugubrella was described by Ragonot in 1887. In 1901, Hamp son, who completed volume 8 of Ragonot's "Memoires sur Ie Lepi dopteres", included a slightly more extensive description [based in part on Moodna ostrinella (Clemens)] and a figure of the adult of this phycitine. Heinrich in 1956 desclibed and partially illustrated the male genitalia. The present paper gives information on the appearance of the last stage larva, pupa and habits of the larval stage. Last Stage Larva Color.2 Head yellowish brown; all groups of muscle attachments usually pale brown, indistinct; small brown patch at notch of postgenal region of head, with darker pigmentation extending dorsally along posterior margin of head capsule; hypostoma with brown to black markings; mandibles yellowish brown between articulations becoming dark brown to black distally and dark brown to black along lateral margins. Prothoracic shield yellowish brown to brown without any distinctly contrasting patches of color. l'respiracular plate yellowish brown to brown. Remainder of prothorax yellowish white, white or grayish white (translucent pink to pinkish white in living larva). Mesothorax and metathorax yellowish white, white or grayish white (living larva translucent pink to pinkish white; young last stage larva with internal organs readily evident, including dark purple gut and pale, whitish tracheae); mesothoracic ring pale brown to dark brown, usually darker along inner margin. Thoracic legs mostly yellowish brown. Abdomen similar to mesothorax and metathorax; caudal segments usually more yellowish (living larva with pink and dark internal color not as evident on caudal segments). Eighth abdominal segment ring pale brown to brown, usually paler than meso- thoracic ring. Anal shield pale translucent yellowish brown, without distinct markings. Peritreme of spiracles pale brown to brown. Structural characters. Entire length 12.5-18.5 mm. Width of head 1.19-1.32 mm. Mandibles (Fig. 1) with 3 distal teeth. Sensilla styloconica of maxillae (Fig. 2) simple, tapering to a point, curved mesally. 1 Paper No. 4769 of the Journal Series of the North Carolina Agricultural Experiment station, Raleigh. 2 Of preserved larva, unless otherwise indicated. 134 JOURNAL OF THE LEPIDOPTERISTS' SOCIETY 3 4 5 Figs. 1-5. Vitula lugubrella. 1, mesal view of right mandible of last stage larva; 2, mesal view of left maxilla of last stage larva; 3, lateral view of head, prothorax and mesothorax of last stage larva; 4, dorsal view of cephalic segments of pupa; 5, dorsal view of caudal segments of pupa. VOLUME 30, NUMBER 2 135 Most morphological characters similar to Vitula edmandsae (Packard), as described and figured by MacKay (1972), with at least the following exceptions; On the head, L1 distinctly above imaginary line between A2 and A3 (Fig. 3) (V. edmandsae with L1 very close to, or on, an imaginery line between A2 and A3); prothoracic shield with distance between XD2 and SD1 only slightly less than distance between SD1 and SD2 (Fig. 3) (V. edmandsae with distance between XD2 and SD1 distinctly less than between SD1 and SD2; abdominal segments 1-5 with D2 setae about 2X longer than D1 setae (V. edmandsae with D2 setae on 1-5 about 3X longer than D1 setae). Pupa Color. Yellowish brown to brown. Structural characters. Length (excluding cremastral "spines") 8.3-10.0 mm. Width across mesothorax 2.4-2.6 mm. Head minutely granulate on front; vertex broadly produced anterior to prothorax (Fig. 4). Thoracic spiracles distinct, narrow, protruding (Fig. 4) dorsum of metathorax with 2 groups of about 16 shallow punctures. Cephalic 1f2 to % of abdominal segments 1-3 with numerous shallow punctures; punctures usually do not reach spiracles on segment 2 and barely extend to spiracles on segment 3; segments 4-7 with numerous shallow punctures encircling segments; segment 8 with 2 groups of dorsal punctures and D1 and L2 setae (D1 missing on some specimens); segment 9 with D 1, L2, and L3 setae and sometimes vestigial SV2 setae; segment 10 with 12 stout, hooked setae (Fig. 5); gibba absent. Material Examined TEXAS; Ft. Davis, 8 larvae, 1 pupa, Quercus grisea, Liebmann 9-IX-73, Coll. H. H. Neunzig; 3 larvae, Quercus grisea, Liebmann 28-IV-74, Coli. H. H. Neunzig; 5 larvae, 2 pupae, Quercus grisea, Liebmann 27-IV-75, Coli. H. H. Neunzig. Larval Habits Larvae of Vitula lugubrella live within the dried galls of Atrusca spp. which occur on Quercus grisea. These cynipid galls are of the "oak apple" type and are approximately 15-30 mm in diameter. The small larvae feed just inside the outer covering of the gall on the fibrous material that constitutes most of the internal structure (Fig. 6). Late or last stage larvae also feed on these peripheral fibers and, in addition, frequently tunnel through the center of the gall, including the central chamber in which the cynipid develops (Fig. 7). Large quantities of conspicuous, loose frass accumulate within infested galls. Pupation takes place in a loosely woven silk cocoon within the gall. Vitula lugubrella apparently is multivoltine because larvae, of various sizes, and pupae, at different stages of development, are present in galls in the spring and also in the fall. Vitula lugubrella is the 2nd North American phycitine species known to be associated with "oak apple" galls. Sosipatra thurberiae (Dyar) 136 JOURNAL OF THE LEPIDOPTERISTS' SOCIETY Figs. 6-7. Vitula lugubrella. 6, partially grown larva in gall of Atrusca sp.; some of the frass in the gall was deposited by a large larva of V. lugubrella that inhabited the gall earlier; 7, last stage larva in tunnel made through center of gall of Atrusca sp. has previously been reported by Heinrich (1956) as an inhabitant of these leaf galls. It is interesting to note that Roesler (1973) has synony mized Sosipatra and Vitula indicating a close relationship between lugubrella and thurberiae. VOLUME 30, NUMBER 2 137 ACKNOWLEDGMENT The drawings were prepared by Mrs. Lily Shen. LITERATURE CITED HEINRICH, C. 1956. American moths of the subfamily Phycitinae. U. S. Nat. Mus. Bull. 207. 581 p. MACKAY, M. R. 1972. Larval sketches of some Microlepidoptera, chiefly North American. Mem. Ent. Soc. Canada 88. 83 p. RAGONOT, E. L. 1887. Diagnoses of North American Phycitidae and Galleriidae. Paris. 20 p. RAGONOT, E. L. & G. F. HAMPSON. 1901. Monographie des Phycitinae et des Galleriinae II. In Mem. sur les Lepidopteres. 8. St. Petersburg. 602 p. ROESLER, R. U. 1973. Phycitinae. Parts 1 and 2. In Microlepidoptera Palaearctica. 4. Vienna. 752 p. & 137 p. SUMMER MONARCH (DANAUS PLEXIPPUS) IN SOUTHERN TEXAS (DANAIDAE) The monarch, Danaus plexippus (L.), is by far the best-known butterfly in North America. During several years' personal observation in the Brownsville, Cameron Co. area of southern Texas, monarchs were normally observed only from late Sep tember through April. Adults were most commonly seen in the fall and early spring as they migrated south and north, respectively. However, in warmer years monarchs were observed during the winter months. Other observers (see Urquhart 1960, The Monarch Butterfly, U. Toronto Press, pp. 165, 172-173; Yeager 1974, News Lep. Soc. 1974(3), p. 3) have reported similar near total absences of monarchs in southern Texas during summer months. Summer breeding of monarchs is normally limited to northern Texas and areas to the north. However, in June and July 1966 larvae of the monarch were found in Browns ville on milkweed. Adult monarchs reared from wild larvae in the laboratory emerged on 17 June (2), 19 June (4),3 July (1),5 July (1) and 11 July (2). Climatic factors could have been involved in this southern extension of summer breeding of the monarch in 1966. Temperatures during January-May were cooler than normal. January was wetter than normal followed by three months of very little rainfall (2.16 in.) until a very wet May (6.05 in. vs. normal 2.50). Another possible factor needs to be considered. The monarch butterfly is subject to cyclical population crashes which have attributed to a cytoplasmic polyhedrosis virus (Urquhart 1970, Atalanta 3(2): 1-11). The year 1966 was characterized by generally low populations throughout most of North America, including southern Texas (Urquhart 1970, op. cit.). If the monarch is less prone to migrate during low population periods as suggested by Urquhart (1970, op. cit.), this aberrant summer occurrence of the monarch in the Brownsville area may have been the indirect result of a virus outbreak. RAYMOND W. NECK, Texas Parks and Wildlife Department, John H. Reagan Building, Austin, Texas, 78701. .