SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ed069ebc96e3f62e3f22e174fcc70e91b5c57c2e721ea8e6786d8d35e3a9940' 
  AND token = 'opiFPubB0IoBf2gFDwsJwa7qFj/CGUMRuV3JXvznJrY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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