SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e0b6f4a20014cfb657ad0a2e764e5d6a6405039568e2442cef42ece27755bd4' 
  AND token = 'P9WgM7TsCXr0QyV/r/CBF5HADwduQrLKFjtgWz9QLic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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