SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2d7b4369bb5879d46753f67a1316539d654f4f904e2bf8e35a54c9d053a540b' 
  AND token = 'JnhgNR/PSuT2Onyghodhy4S5jbxGqP+WYcs6A5QILtA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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