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RAPHANUS. Radishes. [Brassicaceae] |
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Two species of Raphanus are recorded in Britain - Wild Radish (R. raphanistrum) and Garden Radish (R. sativus). The BSBI provide a downloadable plant crib for Brassicaceae. Five British miners are recorded on Raphanus. A key to the European miners recorded on Raphanus is provided in Bladmineerders van Europa. |
 Wild Radish Raphanus rapanistrum |
Key for the identification of the known mines of British |
1a > Leaf and stem mine: Oviposition takes place in the leaf blade where a short mine is formed until the larva reaches the nearest vein which is then followed downwards, with the main feeding occurring in the mid-rib, petiole, or in young plants, also in the stem (Spencer, 1976: 490). Pupation either internal or external. The mine begins somewhere in the leaf, generally at the lower surface, not far from the leaf margin. From there a corridor runs randomly, until it hits upon a vein. The corridor then follows this vein until it reaches the midrib. Then the larva starts to bore into the midrib, and may descend into the petiole or even the stem. Pupation may take place either within or outside the mine. |
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Phytomyza rufipes Meigen, 1830 [Diptera: Agromyzidae]. |
1b > Leaf-miner: A distinctive mine primarily above mid-rib, with irregular short lateral offshoots into leaf blade. Pupation external (Spencer, 1972: 51 (fig. 172), 55; Spencer, 1976: 270, 271 (fig. 486)). Branched, whitish, upper-surface corridor; main axis overlying the midrib; side branches overlying the main lateral veins. (In Campanula and Phyteuma the mine is much less branched, sometimes nothing more than a corridor on top of the midrib). Frass in rather long strings. Usually the mines begins as a long and narrow, shallow, tortuous lower-surface corridor that ends upon the midrib but otherwise is not associated with the leaf venation. Often this initial corridor is filled with callus, and then even less conspicuous. Pupation outside the mine. A linear mine on the upper surface, usually following the midrib and showing side branches along the veins. The frass is in strings. |
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Liriomyza strigata (Meigen, 1830) [Diptera: Agromyzidae]. |
1c > Leaf-miner: A short, irregular, linear upper surface mine on any part of the leaf. Also recorded from young pods (Bland, 1997a). Long corridor mine. As a rule the first part of the mine is lower-surface, the later part upper-surface. Often the loops are so dense that a secondary blotch is the result. Because upper- and lower-surface corridor segments often cross, the mine obtains a strange array of transparant patches. There is no association with the midrib. Frass in strings and thread fragments. Pupation outside the mine; exit slit in upper epidermis. Mine not associated with the veins or midrib of the leaf (It is this character which enables distinction from another Agromyzid pest species - Liriomyza huidobriensis). The larvae may leave one leaf (if not large enough) and enter another leaf, via the petiole). It exits the leaf to pupate through a semi-circular slit in the upper surface of the leaf. |
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Liriomyza bryoniae (Kaltenbach, 1858) [Diptera: Agromyzidae]. |
| 1d > Leaf-miner: Corridor-blotch mine, normally dorsal; usually whitish; in small leaves it lies characteristically in the centre of the leaf often touching the petiole; in larger leaves it lies to one side of the mid-rib. Frass deposited in green clumps near the leaf margin. Pupation usually external, sometimes in a separate pupation mine. Oviposition whitin the leaf, at the lower surface. The first part of the mine is a long, sometimes very long, corridor, that mostly will be overrun by the later developments. Generally this corridor is directed, frequently guided by a thick vein, to the midrib. The next section of the mine is large, irregular blotch overlying the basal section of the midrib. Locally large chunks of midrib tissue are consumed. From this central blotch excursions are made into the leaf blade: generally upper-surface, less often lower-surface and locally full-depth. In plants with narrow leaves, like Diplotaxis, the mine may occupy the entire width of the leaf. Often several larvae together in a mine. Frass blackish green, powdery, in clouds, sometimes along the sides of the corridors, later more in the periphery of the mine and in the end of extensions of the blotch, sometimes seemingly absent. (Often the frass can only be seen after the mine has been opened). Pupation generally in the ground, rarely within he leaf, in a short mine without frass. Hendel (1928a) described the biology, larva and puparium. An initial narrow gallery then leads to a blotch on the midrib of the leaf. Watch a video of a scaptomyzid fly larva on Arabidopsis on YouTube by mash92587. |
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Scaptomyza flava (Fallén, 1823) [Diptera: Drosophilidae]. |
1e > Leaf-miner: Rather small, untidy, full depth, often branched corridor, often close to the leaf margin. Sides irregularly eaten out. Frass in a greyish-green central line that is interrupted from time to time, sometimes partly in strings. In times of rain the frass may run out and appear greenish. Usually several mines in a leaf. The body is whitish; head greyish brown with Y-shaped lighter marking. Pronotum with a pair of brownish shields. The mandibles have two teeth. |
 Mine of Ceutorhynchus minutus on Raphanus sativus Image: © Willem Ellis (Bladmineerders van Europa) |
 Ceutorhynchus minutus larva, lateral Image: © Willem Ellis (Bladmineerders van Europa) |
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Ceutorhynchus minutus (Marsham, 1802) [Coleoptera: Curculionidae]. |
| Last updated 06-Jul-2019 Brian Pitkin |  |
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