SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be22610746a8669537398bf2103fc19d38e0c75c002650b3530e4a90e8350a37' 
  AND token = 'EXtYjht9OoAeUQ8rK5jrtW7iY2nOitJWYpjVJtJNnVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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