SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a5575b17166a9af1c31d7b867da0f23c8ce315a47c7aa55ffcc98de5051b90e8' 
  AND token = 'bsUvTDIwi8d9mSBcrdQElwJv/JRKdDnoWSZHXutyWmc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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