SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '005a8d183713275f1575fab030f605b4282a54ae79f26636856696ac03d05cec' 
  AND token = '0Ig9BD/RY/CtJIvVjIhr9Mu3Qm5TqS0MNGVJkBOzK4Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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