SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bbe7e4cbcdfb1755234fbd3a35b733e6fa7c3b07643f042717d5ade9c04b26f' 
  AND token = 'hknCYJ9cFiOjdxEifSlwqXm4PEYOhL7kLJ9GpBwsu8I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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