SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ecb7b0df9b8bce816359a699cacd6039cad7700e5a2936f200dc1c81159d9c5' 
  AND token = 'Gb8jEjfr+7M3QbpLyZRZw19alMghyKEbPwfMOSPelYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}