SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5f31ae1194d24de16e6beffd7c3149dba93d314ab772f43a70de3c809ce3d48' 
  AND token = 'Np1hT/jHHrrbykbGHVR+elbrjRZAsiq1x/9pkr4GYUE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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