SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce3d47a55b9a448f85a100600754f8136422d91b05dffd8ffb290bb376c56763' 
  AND token = 'G0LLCK2sFG2Hd+BL7G68Z+oxdx3pqxyalhtv7kvSgss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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