SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f25f9d96f4a38bb21a4397b60c43b7ef9d5cfde7dd7bcb5458966325fb57bab' 
  AND token = 'TEIaVGJVq1dqy72Tc+6v4XIvqLNLRpxmCnCFQUhut+U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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