SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c467d484cf67b732a5f6a6496917aa0fa927bba3fd6d6a3a4f1721bdf0069c2' 
  AND token = 'I98vC1uk6Ei31lwoJA1ahVzXtwYo//8utolcv5AAgQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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