SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b2d6bb08176ad0f8ca109d405674c393c850f9e222cf60772e308516ae2780e' 
  AND token = 'Tztjja+v2ULDpyO1hF/hK+RQa8P/A4UK5dewto6jrZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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