SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fca468ca1b932959ee3d49ca817ad7f2663a7b399140a9d78ee1fd2aefb4941e' 
  AND token = 'AXozzegoo6MPDAFsSOb+9YCg/U9PIvlHPDDcYWYO4FM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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