SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '824da00cbad384e0a4e639474ac20c8df1cc5aaafa028756705f233787ec114f' 
  AND token = 'vGhwMoeTxiKnY7jnrDxj8pth4lMlPwcvJ6HWEVXdGs0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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