SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf40f4ac4a89d51a89dfd17790d7e4b7ec54878551c93fd416efdb7d022950df' 
  AND token = 'yRsOiyY9iIYZ0IGrbDKjpEz9aUBduIotJtrZ65whn/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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