SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98ea5a66b9da9454a3aa4e2a4cfb791e2770638bf1f171d47ce24320f4dba48e' 
  AND token = '69bWTUa47KHqgIO6BWzMNtR2VOCfCwSq2SJ9Z4sRYFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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