SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a42ce199dae0ecf3d06caebe00b1db4522b650613075d65597f5181c7af8d174' 
  AND token = 'wk1PmLxlxViDfhIsBJ4oGtneDoWV0q96M5Y9fHZLYgM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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