SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa287e0c30d5fedb4f2481afd4b769855d8fd04a4238f4d6646838cbab18da64' 
  AND token = 'e66F83RWnhwIHNE7edt3XnEb5IPfj5Pcb7Pb1FaOa6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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