SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7b17fd97eba8d1c8ed57092c56bbfd38c3d2c293d2fea5a2814871bb85526c6c' 
  AND token = 'mgN82NKLPZXQWUbIoZIjea85oF7kQsAEXT1D+JJWIn8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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