SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ee1ae1f756f4e36a85b609538efbb7fb4506b4758020c662ef84e8c3409e914' 
  AND token = 'fQHGRqYtils/ntzt64dwfJjvVuqBhEFhDbb9Umv3pX0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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