SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4b9cd1d501380b6afdc12a3af765d9356d5cf746fbb3d3b7d294015c8a5f6cd1' 
  AND token = 'on2LaNicBCoxqaOSO7oCSK4hmEI6Yuhplb2BIzGTu/4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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