SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fd12aa3ec3df7923c86cc1d86787007adaa95c7ad70535de3fcc0cd2da13389c' 
  AND token = 'mKGHy6dc1Daji4uwn7a3EEuLZdge+OC2Zkl+LN3mOso=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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