SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6509714b53458f35f8530b9b6fb56bd03726aef2d3d9db764feccd5972c6f23a' 
  AND token = 'OA9HYIzAMkUfllWFovTQDCkWVkbNHg7b2KMXIVymIbg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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