SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a2d49e2e4c477302f069de7be13d18ba1ae4c71f0d8e65c6dabb2e7070556699' 
  AND token = 'S3MapjR4r32cWcEBW4ieWqxDE53VpCkWFm76nELwXWY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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