SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf9218123049e6aabc9d6ca0de5f7c8527961da81dcf9e661794eb16aaf4d099' 
  AND token = 'F0Dz1rmOfaCKkOi+YZ2igDI78RkrsWd3SnRuQZVp8PE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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