SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7069939e94a70627654c58dd44a3ccaf99c8ec3f71b9f28aed1c728bf7aa359c' 
  AND token = 'yFJUGfLimILoLjsGoaCmC8mKcIEK0pzdm5AbENcARjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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