SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '15241f11b1815ebde4d341c8f60639ae2425ff9cc3ab5538aadca67ff3b60d99' 
  AND token = 'mNxtE9ppSlNqhUFtzny8fIyNxEZs0OGHeMfYyhOZef8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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