SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63c9071f836bc3a8f764e34e0448236c8a3794e5050811989dda51416b5a38ae' 
  AND token = '/4PPJt+HjIgO5h7xDjOABm9Ttg0mxFLjd/fCrKH+zm8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}