SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '489d891c042763ed4a7c92aa4e4b5831ac73fbb67979e401d328018d7ff7919e' 
  AND token = 'rUaRZpnCprLM+8j8amzf0KwPN74sC7KfTsS2r28loFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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