SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff89437aa8a40018bc20534b7e72484ede937160b3c2ce5936dbabdd87365b05' 
  AND token = 'bLTH10MHbs03vIh/VJ1pA8fbeZKaQP0QvYhGI+mTHHM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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