SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9136c2bcf82ae249ede3f5768dd6c9aadbef21e9030c61cc1e06568acd185380' 
  AND token = 'eqPMLViwEi/v++E0SOipLXRsZUHHL+NJgCg6CyqRPkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}