SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa7731cf2fbf17e2aeb985d551b3c479e84f1f41f0a89595ab4e802d4ac44af5' 
  AND token = 'Ba9PqJVzPAoDszLsl4HMGHuS+nOLmfz0Pkh585jrjsk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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