SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17be834351c35c1f839e9865318fa39daeeb3aa6d77cb0b958cbe51df9b21bfd' 
  AND token = 'uDSaX/6pk9pk/khFLQKpoX1dCPgUAtSJDczhzM3EHWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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