SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7272f9535fbc9ece0154e8cbcb7e6c0d13bd58a7382ca489ff1c043b17c8d9a1' 
  AND token = 'gxjQG0KUZ7Eu+jQK83URWN4OtPp/Gz4qBndosIkuibM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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