SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0edfe8555c43030c648f343cce67e6374286e02174f918ee57b95362f7fa04c3' 
  AND token = 'og2tlHa+Tf9HRzayc8WTCjtRAA6Ly4MAHrw/FUD85p8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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