SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93f974c47f0f838c1a09d88e9944e01547f66e6ae8a4bc6e97e37178ee607eea' 
  AND token = 'flUbUMziYA04TqYudnkpz25YhFeudZufiBmjruZUelI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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