SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b052b64b6db7612647ec79d10d650b696fb1bc894da04051a4cf5bf188fd5c2' 
  AND token = 'xeuGp4oYXOOC9R6jHgXz0VapuUy1QtpnI54KN7mVxmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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