SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bea64d805fdf3fe5c9292c9829d9e8416c868b7e08b6d0221fcb51956cd67456' 
  AND token = 'ZDhumxNvPIoAvfvGx27BOIkPA0d4GwAjaPqPGQUb5+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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