SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e148bfd806f00af65644b1cc9cd66f386b9419e2ca9fc6d1094cba94fc206b3b' 
  AND token = 'NzcCIPDUh0JJtNNfKSLs0saMnIKeebRUycLCGAj1CHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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