SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e928f9ee6855a1f79f65c929ea4ceab9b355f81d2ebe623db79a7187a84c75a' 
  AND token = 'Ge0K/XPfAjBYxBFWkMfD9F4P4+8Y2mlhHfRLVpYmVCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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