SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c59f2f6c3e68195250b602cd02b3cfc03b7c410bfe2fdff0ac8cd482e8881454' 
  AND token = 'EKdGDngV7EGhCFH5TWbFvRaZK780HOvBI3dNDp3CGpU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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