SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cdb1c2058340a8afa6011f1eca2c69ecd0935d09f13e38d92efe102cfb057a61' 
  AND token = 'GKMiiUNJjlesxuzpqd9SaG1B3+/TgPykCH05x42QJLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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