SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98c58a5dbd04a60890d0d2a9dc4725aa29b5e561d805605a5055336e0a839269' 
  AND token = 'aNVd6OzwhuPGAJJGWoBz84aPtinW8663OkLr5Dvv6x0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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