SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1cd3bd776b7d16aa913083c4cbc8566f2b5c6869f1965ada35adf082eb2965a2' 
  AND token = 'EjFNJNea5EyjBJMMI5ZNIkkXWYY5BuQFz1TSGWOdAvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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