SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff60d0d307dd5070cd9d55450d3b1a57384e63f0e3c69c5d3e86a74de14c6ffe' 
  AND token = 'q4k4Hfk7rioGdoc/zRGJDWSd3sVyLWehADwhWWWVTL8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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