SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4063eb247dfdff8d323bf5e27de8cc885ab6f0754bee3a0057c706f882192f2f' 
  AND token = 'KOLyOR07jr0JdzhzQaNxeHYhX0mYahUCpOXL6Y+GMmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}