SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '964b13a477791b62f8d9c18c84f3492db13dedf3afa32a36f029642a3c0ae4b3' 
  AND token = 'tAdfjG7m/BW2z5RhgJdKkTKBCXIAmwzJwhjxnMxDs14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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