SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5750fa71c2243327992ad1b945a4853ffaf0835aaade31aa5872686b95ff43d8' 
  AND token = 'u3gAR3k1oFSrq36k7L53CsuJEmDr6WsSkI8+h13s7Co=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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