SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f1586074eea41d972d3e25df1ff8eb192197e2ade6614cde220e36b836ed7fdc' 
  AND token = 'm+X6oCH4/niQh6fmRfs+UwzKJH0GKWR0tA9u/23zYCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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