SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2829da49973291febcea206cea8225d2a50e93f4fe513df7f7abe2a841606f8' 
  AND token = 'blJHUKhoB5YxJHv+x40wC+6lJUTMkcZ/6I71FX47sFU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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