SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05c551f7874b561a3f70126b713c9650e8eba1f28d2dfdd8bfeae7430f62e9a4' 
  AND token = 'XKsqBNKTJXEwaZ3DtOwjsaW6VfKr+RcOlt23CergNRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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