SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '803dfbbd6eaaa6b088f05a2fd2bd4ba8410e5d1f848d2a8543ca14ee0b04fe7f' 
  AND token = 'PT8/qYl2hpX/nOYk2TFB5/J9Q7HDyXl/T6kmpohaJCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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