SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e506c62ff035cbe0f7f91a7854fe5952c11d9c228038333eee21c63564b1340' 
  AND token = 'qciVgQzGrKADgw4QI44uOCY3MquWZTinL1vf3dV+pP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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