SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61d9fe771da8e680880ad5f2fe07ff62301e0b0c3199ecf6bd0f6b17a001e44d' 
  AND token = 'ShCaWPPwVQRKeHJHHtks/RNU4uJdzWLHChHEN4nKSCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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