SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa9323115504cc73c693f98626f692dfa8702482f64e51c8fef52bd35b57dfd9' 
  AND token = 'mQZ7eDYQweYOGjYo0KbcgCtBzjg6pZgR2to4cEO5C5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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