SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'e5ad8a8645919a24686b8025e5387b8f0afa57c48ed0ff83a6c77d8ad2c71ee1' 
  AND token = 'X5Mo6KQNCUiqKYQX+1Ey6EAKYW78OQ2QS/rfFXfILIQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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