SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c928e0b4b1ba8848e82b244f7d5e9313143c87b265c79143d95dfffdf78869b' 
  AND token = 'qqxugj5O8NTCYPniqW9tZB7yvAaK3kOVDpodUDIMD+Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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