SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5bfdfb41bf79d52aac6f3eae6c3b18263596991ba0cf8e90b713438d6fd183bd' 
  AND token = 'lHhJS/b7I0lj94RnYwBlOxqRD19dCKWNbUJSP00m0aM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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