SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e38f89633a4bd3a140cb539fbd1f05695346eb7896cde8325fb6d2caeab9cdb2' 
  AND token = 'BUm1+K0FOarPWKqLHAm/BF4h8bX176uvHDU8h99jJMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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