SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '603f8340620d94306f1c3387cf8508669424b902d63ce77cf9d5dd804fe0e281' 
  AND token = 'p7O6RZEsF6O1c6I2jcYtxYlTXFJiAaYYjM17teb+nnw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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