SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b214871f5bf2149365a9009b359add1431869df79eb4e686c8dbb52c5f46d25a' 
  AND token = 'iqGzW5ZCQXeZcuAWbhfEM30U0yqN/GpjTTv7nhrLxaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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