SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f47f066d54cb9ec6447e1275de001930f350eeae62a52993e18b704953effcbb' 
  AND token = 'D57TRS5gZL+6lQ9QUnsngauWzMqoB0iibhHjpHs/AVE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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