SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0bfc5afbde755f793958ad3ab0f82ebeaf755a4e219d6e5475a1ee51af22c1a' 
  AND token = '+cSOlfiu/VLplF+JZTHcYOYXcxBqruvxsgofZkhz/gg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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