SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38d493922f7bb97f22bfea8f99f76bb818f80b85abed86ce5183d021880fa684' 
  AND token = 'tC0qPequ1hziRNO9SRZADgFWXI5/q9Akzo1P77Um2qE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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