SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '544e59e914e4483348d30cca9851d0cb7655182ec3a6bca2853d6f796a471833' 
  AND token = 'NFTOfQFIU6g6lzkNK17zrksYOiqhCbu9y40yk+qKcVo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}