SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f767450ac4df8ebb496abe85a039a9762ef7449274332283cce44c9622b206e7' 
  AND token = 'eEwq8EuKh8GgC7sFG39nuO2Rir7RXvKAVy1+gqN0vQk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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