SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccdf41bca7f8de760dbb6f0d8cf52b41eca1854307fd789632850649ec737258' 
  AND token = 'EyRmOL+V9VXFTiUs9TBXXMU2yCj8G/DR3bYB894qujs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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