SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dccbad99b23a8db602b71159d9804f09db96cd1f3ea69424236bf11b614999e1' 
  AND token = 'nJ7D/nR+3lxqlL8YzdzWPhPchQKzCP35k/HZVrQ9Mhw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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