Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '652a11dca0d47f290716164f020c6b8ebe10b31b09a40bf09db3bed1ae9cd944' 
  AND token = '8ayzN4xIddLSk325sSRW+f7nuz5nIltm5gGnGw6maWc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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