SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9226e0ec0779ca214c789b5721aa3d601f5bb95af463a644b8ade46c9b29bc6d' 
  AND token = 'vUg1OQY/2+x5dlDsCSHNJUncumFhgr+FG9Kjlf4oInw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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