SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54606f031a9dbccfce415eb5d913beab8f3c0841e8e61e477db89c5c9e73bb28' 
  AND token = '6tUvegiGwWyxJnY8Pui1pSR3dihtYXUKXEHo7wBiF9s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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