SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '571045e2b9a7ba36784bf8b6d53857d74e26a98aeb3aabffc2acd773a9d65647' 
  AND token = 'Cb96KWO0E+jKkEpkTW5IRRc23xriKQWCUW5rG08IdJ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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