SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a2a04edaba6b8803c06d02272c5d18c7a66e5722fcdd41cc0969fea235a6660' 
  AND token = '3kP9x/uFOKPUHdtCq30a5g/RK9ClfbOfK45bpODJ/Jw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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