SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1227716b523ae682bdd0f94e4fc1d52c706f1aa58140bd13aba85373b9c8fdb7' 
  AND token = 'wkwjRJA6U/0JeUnno7Y7cpSPdvuDDQdq9r9ayUZl44w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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