SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '42195987f7bc3307a10d214009d72c79366cb3fe9b9ec3008659372475193a28' 
  AND token = 'jv0AsdpvUrl+D5t03krRipB1cAieRsMu+LuSaY7T2+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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