SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '034fc46e2ab3657beb25b8b8d72cc2a12fc793c9339e65f0a263f96d51c8ea33' 
  AND token = 'x0UetzZ1vGN1xZSey3H3dHGn16UiqhA/907DrELzLf0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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