SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e63d14c9d3fe73fc13e376a651f147bdc9a3c369f38c3c9b64cb199c4da3aec6' 
  AND token = 'Znj515UBoJisHD+jY8UIUvNz/VuGRLgo7u72qLNmwKw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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