SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7669162144f00808883a3f2e244b9372c138c95ab6f771ae9e6eb15120c268e6' 
  AND token = '4HtgtaGBXCAJWnkdhAxSYK1K0WXRY2HJKJg/U0E6Vg8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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