SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f2521fcd9005e219dd9eeb046d98d73734e8863b3b28a634ba876683921c00ff' 
  AND token = 'BQR7iyrBAuvv1EkHXcd52J7mRShWg5sWdOWfja8PpU4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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