SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d70dcef64b588f4ab9c75932c8f06ce00fb15fbb149a1f289dfd23789c8843f' 
  AND token = '6Etv7eOqAGY35fg+VWmDIVQRK19p4KDXU1V/VPjSB/Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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