SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdd192c6ce27216c52f2a0e7cf7d6cbdbadf7554dc59fa61ee2a8d980e89a40b' 
  AND token = '1yzJE8svKeurwLbccL+XYFCjgXPaO4hqE+jYtezE3F8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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