SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ed02021c27072b41892ba87bd7dc79210371a6f87b5258eb8ec14ee0e6c8efc' 
  AND token = 'DWiU4jj7g8JtmLETJr3YNn2F50TAkYzZw9DbGQ1d0cQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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