SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '880c48745c378800a01bcbde6e54f75aec902dfa0505d1235c62887d0f88f0a2' 
  AND token = 'PVy1o5Ee43IPyv9sbf0YmVYKPyVN3jMgcIfQ2iS/QV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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