SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e25f7dcf8a70f90ac35cb61da8a3ba234e9f9f58ed10967f7880644c4ce2e950' 
  AND token = 'eA4VgnX3crEfgXNGVHJ4HNAJBxSwY+vAxkPq7ohh4eI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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