SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdf66895327fdb39698c14f2f921db61f41a51ac8d5ded142c3603442bcea3b6' 
  AND token = 'cTfGfAQlMhID53nFJ+y7Nq5a6bR3N3g9EYTuf/UOXg4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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