SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'def5597d21c5c6697ca1dd7d24ac6b4506e92757c444fac34d25a81069b63639' 
  AND token = 'JpfE85zEDqy7HU8+EbsOh1CQX9KwgYOwwybGA0GK1Kg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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