SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64194f44b452758fe083941b6e45dac7cd9350555c491b9cdb5ea506a270153d' 
  AND token = '/gCXqyzQAfiaFslTuHT2GRPgUWpm7vKdYkvmZ8dgrMY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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