SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25adaa8891abac57d255679c5fd9cf6063953c9e78de1aca571890d4df4aa05f' 
  AND token = '1aaBFcnEAHUz7s81qzmRZp3WI7mPqRR+VOUxtqtapGQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}