SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c2f69c58792097f70174befcf45e533a63f1685e3d72840c195800e9ec82639' 
  AND token = 'XLS1g6hBmWjTjqcHJ4IFZUQZwV8Qtf3nhaKLqjxRmuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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