SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fa954ec9c19343e09cd28e25fd5ecc85049293d94545697d579054819496a39' 
  AND token = 'K6affwLgUuzfx73eLwdvcz1SU3KW0P1dqCFytqXRdZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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