Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8dfe301fc6875f82abbc7bb4b6daf0d0b8e45bdb3fdd23482b4b281d1a6f1397' 
  AND token = 'iu8pwIIfVfz+F7zPwd520+DR98GCoKv4EGYc2mKcaU0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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