SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ba5b3106911c6298ca5a2a5cb9229a0fa09d7cbd970d3de4def27fd1d24c1ea' 
  AND token = 'oGWY5dtH6CWjegcoYA3aDa5k+DcWqY4O7TLPhe1W0pI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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