SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '71690e5463faf0ecf5bd48e11a58e00ab825312007f7d7ebd77c299dffc588ef' 
  AND token = 'e72+stK0OY0rrh/DZ6uBAnm4XyhKqGrqQ6rJhpD13+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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