SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d92175ab441bbccd86413a7dca2263b1bbb71d0f91d7b411a614e6904f95bfd' 
  AND token = 'AvaDAYtAekHtFgkguaTfrwYFPawQMlFKS0lAKyVwElU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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