SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3c3cfaab16c596b7baa65308679cb1546330038d2151f72d05f09d20f248e79e' 
  AND token = 'fa8kKme7TJbzEPe1QC73sq9ftVgp6ZtLcAogwYVICqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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