SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1cb41a927c378f63827cb48ae184b14fd2ff114911bc125fac1159cf9458edd7' 
  AND token = 'Yk8Rz8N61vFKhaZn8IK6PRSNvEi4j73wAjf48xapWQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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