Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a919f2e38d05bec135d9483b051fcf3fc3db13abe9c6d987b9523493d23afa22' 
  AND token = '+BS517NRzZJnuT32o0RohsDnytDqxXO8hZQT98Ad1po=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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