SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2cd383815dabce1e416201698ea36110d3bf6f02d4876259d427e65111e535cd' 
  AND token = '2dIZOwmz4dUYdAuiivbMxwzhHiMYbStM8B+PIOYb2tA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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