SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd05870b5c52df7ea238c077196925db9f8af3dd70b46d50cb4c718c146f4658' 
  AND token = 'J9mB0ZWuizqs7TAbo3I/Xa423zY7hMqCkkMJc0FUpcM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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