SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '65d6af4b3313c561196c9e6fb3fb923e864c894ff24fe68c874c8e8c08932db1' 
  AND token = 'MU6dOsJLTR7LWytwJsscxjGjBLttG2MXcO0jSocIhpg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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