SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '78c19fddbb317b63517cfb0ef0c733da6349166355814e4b59a29565727d27bd' 
  AND token = 'Bsc6hW/R0IVh55+Dg4Qkt+r5xHPwozj1V1nISfl32qs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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