SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '422315a4525b71cb1230be17655a3213cb3643ff5676cfff5f52bb696d94173f' 
  AND token = 'r+9rnjxFGxKYJYhoTO3GvpKd93btcQAG3Jag2JDTGpA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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