SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e9b1a1284a329d5623acbcfb6e234ea9efba1469ab7371f3fe3864896da1792' 
  AND token = 'zpTtWIV1qqCzqUpC8PEGX/gJccoQ1FXu8SRtYotBC1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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