SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '372c0fc88e250ef0ce492a50e431705f29ba9a6c4a0b06b5420eb0d8e81aad8b' 
  AND token = 'Xs3Wi1SWU5BMdL+I4dge4HWd0Mbah6U+cwhjKEyPTVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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