SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7eb479ee1c38c61cef4ad8627ced61c56d41cc0497de8eaa3070c063b593b423' 
  AND token = 'WoDw3rREOK9+RAGL1jmmX2y2EPBcNEvlbTRlDJv+Sbs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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