SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ef9d38512ad9d4ffd325fe7031cf66a9b014be623787bd0563a33ec8ac1f869' 
  AND token = 'YF2EX4G3KXMjH90o7Urglf9dm1E/VErEF7uEa6kudOo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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