SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1418b8fa665ae3f7a085333fdcb843e48bf39ff917845045594f66c086e46fc8' 
  AND token = 'XN6KxWVriMj0nwdhu5763rXr2vYHvE9nXdKLDGX+AaE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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