SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'aa5fa25a4df0b18226c2bcda86036b68c3df14d32f43e790564f27cf92b62bbc' 
  AND token = 'c/Ms8cEIvaIKXr+tXMhHiLpvPoOzkOo6XK6omRaDzaQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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