SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fbebd2147ba487f410cb2311e60e49c18bebd6da519679dcf25ad693d7ccd285' 
  AND token = 'lVpXPAZDPwSlOKePVrDJDcpacHVYknL0UYb9+U6aWL0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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