SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ea5349d4ff0961e967951128e4648a46175a272ca43a781e6f2fb839fbb4068' 
  AND token = 'm+Tumd2ouTH/qKpPK3EJtT+5I0emNb+y+Kah/I0KaUI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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