SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5552d452f5d74bcef594cb6f961400a945b077c8565931101dcdd7c790560f8' 
  AND token = 'oX/RRk73OhoFGwAd33OitHpFHJibWwaljOTNX9c1pCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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