SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9913dfaa97a31eb16bf860847f7154deb5120aee1d10dd9c2c8812324bb7e009' 
  AND token = 'tUwyskUsvQXwobvc+YNRHg15FqQCsGyznJul7VuPiIo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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