SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf154fa5532179e0f2611751748abde392aeb794522c12a930e9664185f32c5d' 
  AND token = '7+rQ6UcRKIZZTnT47hyrQQcN8j7GHOyPeJfWKIsOph0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00132

JSON explain

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