SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc8e63f779e3d2524595792c74fc1e581e733c07cd3133451eeac619d739ffe2' 
  AND token = 'sv1fx3YeJWOiiUatt+z0guUHHWC0t8QXblhjpoWlpHo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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