SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '53e3369fab71120947d7fc07c785704cf62ecfdf3ad7ebde6890740045c77544' 
  AND token = 'o/TSj2mA8ryiVBiXr4HXLEHnLTfJXn9OkDxJcJt6YFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}