SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e896e30886739b8562109681afa140aab0ecfe6ce68fa62bba13f7dd3b3a90fa' 
  AND token = 'ZJTYNS09jeXDmjrpMauuWtlkeL6akZwsJdck3bGdcqM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}