SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17be3fad7b5898fb7102ed0222d77ed02e0d43c84825d1e2dba537061a9fc5ed' 
  AND token = 'HZOueqSySdPXlz0yb5WMuh8YloaRXhdv5vY6l3UQhH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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