SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4313f9d92e8565cc8d99e7ba7464ed62dd985d71cb8866860b3ce79f32c833d' 
  AND token = 'EYlOpWMLAd7cPwjmNfydACFwpDnwb+HIKCnrqXgQX7I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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