SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdc785a3197c9adcd253f982f7b3e494ff69535acb22ffa8f675c05671605e76' 
  AND token = 'coYR2dRjRQtDLxQYpZHueA6bRHRn6qZjiXPwoCF8CRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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