SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54b9bf647bad3dfaaa1f1dafa4bbdf2fe50c06b0486e542366ca7b17a325d005' 
  AND token = 'efMRdIapynnKsabA0JQ6h36FcjwfTLlmeENZzd/o5WU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

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