SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '535e0bfd261bfb8d9f48be129f076ce9f9d261788170d8d3a53dd978831bb342' 
  AND token = '1yf1L/57loRMgetRWUV5c0T0Nb+JaJaO5IEvsNOHKAc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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