SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d428eb81c1621b14e3c1184ead0b741a5245cc6b046e2972ddd609736dee93d' 
  AND token = 'DjPgMiVen8Mn1ftjwLRJkewmBmFm78WFnn16V5DJJEA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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